Fast Wides vs "slow" wides and night photography

[FredrickSummers]

I currently have a Fujinon 90mm f8, but someone interested in my Horseman 45HD that is currently for sale wants my 90 too, which I have been thinking of parting with anyway.

There are two parts that have me considering a faster 90 then the f8:
1) greater coverage while using Dayi 6x17 back (5x7 coverage), which the fuji shows slight vingette at f22, and gets worse if I open it up at all. One of the faster 90s with more coverage I think would solve this as well as let me get more movement when shooting 4x5 as well (I have had a few issues before with a lot of rise and tilt).

2) the part that prompts this post: night photography. I have made a few attempts to shoot star trails, but I have yet to get anything with my f8 even wide open, and I got SOME but not very good (which I account largely to technique, but what I got was still very dim) with my fuji 210W 5.6. All my research, the only real difference in these is the coverage and brightness on the GG. What I cannot find though is how these faster 5.6 and 4.5 lenses perform wide open or nearly wide open. Also any real difference between the 5.6 lenses and the nikon 4.5 (one I'm leaning toward)?

Thanks everyone, and feel free to post star/night sky photos taken with any of these lenses as examples :)

[Drew Wiley]

The Nikon 90/4.5 is a superb lens, and the bigger max aperture does make it somewhat easier to focus. But the first problem you've got trying to use it wide open is the film flatness issue, along with potential film plane accuracy issues, of your roll film back itself. You might need to stop down some just to get a truly accurate image. Otherwise, shooting wide open is going to have more falloff than a couple stops or more down. This will be a bigger problem than optical sharpness, unless you just don't mind the falloff with its darkening toward the corners. The correct center filters aren't made for wide open use, and even if they were, woudl add one and a half to two stops of neutral density anyway. You might need faster film, unless you have already hit your limit there! There is also a substantial weight difference between a Nikon 4.5 and the f/8 version. But if your camera front standards can comfortably hold the extra weight and bulk of the faster lens, it should solve at least some of your problem.

[FredrickSummers]

The Nikon 90/4.5 is a superb lens, and the bigger max aperture does make it somewhat easier to focus. But the first problem you've got trying to use it wide open is the film flatness issue, along with potential film plane accuracy issues, of your roll film back itself. You might need to stop down some just to get a truly accurate image. Otherwise, shooting wide open is going to have more falloff than a couple stops or more down. This will be a bigger problem than optical sharpness, unless you just don't mind the falloff with its darkening toward the corners. The correct center filters aren't made for wide open use, and even if they were, woudl add one and a half to two stops of neutral density anyway. You might need faster film, unless you have already hit your limit there! There is also a substantial weight difference between a Nikon 4.5 and the f/8 version. But if your camera front standards can comfortably hold the extra weight and bulk of the faster lens, it should solve at least some of your problem.

Sorry, I should have been more clear. Using smaller a apature with the 6x17 back isn't a problem, although it would be fun to try stars with it, shooting wide open I'm more curious about using it that way on 4x5. I started using a Graphmatic for when I'm shooting open as it seems to hold the film more flat and is a bit more accurate. I'd likely stop the 4.5 down to around 5.6 so it wouldn't be wide open, but still more open then most other lenses of mine. My camera is a Wista SP and it seems to be built like a brick. How heavy are these faster 90s though, as I've heard this before, but didn't expect that huge of a weight difference.


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[Bob Salomon]

1 the faster wide angle lens, from any given manufacturer, covers a larger circle then the slower one.
2 because of the larger circle the fall off starts further out from the center so it is less then the slower lens over the same film area.
3 Schneider, Rodenstock and Heliopan made center filters for large format wide angle lenses. Nikon and Fuji didn't.
4 from any given manufacturer the MTF curves, distortion curves, fall off curves are better with the faster lens.
5 none of the Rodenstock, Fuji, Nikon or Schneider wide angle lenses perform optimally wide open or near wide open. And all center filters require that the lens be stopped down at least two stops for the center filter to have any effect.
6 all of them are optimized for f22 and are diffraction limited at f22. For star tracks that is probably a moot point. But are you only going to shoot star tracks?
7 if a lens is a stop faster at a given focal length then it's front element is significantly larger in diameter. This adds more weight, just for the lens element. Since the lens element is so much larger the diameter of the lens barrel is also substantially larger and, since it is metal, it also adds weight. Then, if you check the number of elements you will find that the faster lens has more elements, that adds weight. For each element, or groups of elements there is mounting and centering parts within the lens, this adds weight. In the case of the Rodenstock 90mm 4.5 Grandagon - N, it is mounted in a 1 size shutter while the 6.8 Gradagon-N is in a 0 shutter. This adds weight. The formulation and specifications as well as the performance of the faster lens is always different then it's slower cousin.

[Drew Wiley]

Typical wides aren't rectilinear anyway, so will stretch things and points of light toward the corner of the field. If you could sacrifice some of that width, and use
just 6x11 of it crisply, or 6x12 so-so, I'd recommend the 100/3.5 Nikkor M. Not much use wide open either, but being a modern "normal" tessar rather than wide
angle design, will have comparatively little distortion of falloff a couple stops down - still pretty fast, and a tiny lens. No good for full 4x5. Maybe there are other analogous lens suggestions. Give up some of the angle of view and you could select from 110 to 125/5.6 plasmats perhaps.

[Bob Salomon]

Typical wides aren't rectilinear anyway, so will stretch things and points of light toward the corner of the field. If you could sacrifice some of that width, and use
just 6x11 of it crisply, or 6x12 so-so, I'd recommend the 100/3.5 Nikkor M. Not much use wide open either, but being a modern "normal" tessar rather than wide
angle design, will have comparatively little distortion of falloff a couple stops down - still pretty fast, and a tiny lens. No good for full 4x5. Maybe there are other analogous lens suggestions. Give up some of the angle of view and you could select from 110 to 125/5.6 plasmats perhaps.

But they don't get him to a faster lens.

[Drew Wiley]

For a price you can get any lens you want. They make them right here in town. Just give them your NASA, NSA, or DEA credit card and wait a few months.

[Bob Salomon]

For a price you can get any lens you want. They make them right here in town. Just give them your NASA, NSA, or DEA credit card and wait a few months.

They make them all over. Just contact Qioptiq. But they may not take a credit card.

[FredrickSummers]

1 the faster wide angle lens, from any given manufacturer, covers a larger circle then the slower one.
2 because of the larger circle the fall off starts further out from the center so it is less then the slower lens over the same film area.
3 Schneider, Rodenstock and Heliopan made center filters for large format wide angle lenses. Nikon and Fuji didn't.
4 from any given manufacturer the MTF curves, distortion curves, fall off curves are better with the faster lens.
5 none of the Rodenstock, Fuji, Nikon or Schneider wide angle lenses perform optimally wide open or near wide open. And all center filters require that the lens be stopped down at least two stops for the center filter to have any effect.
6 all of them are optimized for f22 and are diffraction limited at f22. For star tracks that is probably a moot point. But are you only going to shoot star tracks?
7 if a lens is a stop faster at a given focal length then it's front element is significantly larger in diameter. This adds more weight, just for the lens element. Since the lens element is so much larger the diameter of the lens barrel is also substantially larger and, since it is metal, it also adds weight. Then, if you check the number of elements you will find that the faster lens has more elements, that adds weight. For each element, or groups of elements there is mounting and centering parts within the lens, this adds weight. In the case of the Rodenstock 90mm 4.5 Grandagon - N, it is mounted in a 1 size shutter while the 6.8 Gradagon-N is in a 0 shutter. This adds weight. The formulation and specifications as well as the performance of the faster lens is always different then it's slower cousin.

Bob, thank you very much for your detailed reply! By night sky I do largely mean star trails and moon lit landscapes. I'd love to do some "stars as points" but I just don't think that would work on large format. I'm hoping to get away without and expensive center filter sticking to 90 so far. Do you think the faster lenses need it though? The other option is always the Nikon f8, but if the faster lenses can make use of the speed at night it may be worth the cost of weight/size. Normal day shooting I plan to continue shooting around f22 (my "normal" apature).


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[FredrickSummers]

Typical wides aren't rectilinear anyway, so will stretch things and points of light toward the corner of the field. If you could sacrifice some of that width, and use
just 6x11 of it crisply, or 6x12 so-so, I'd recommend the 100/3.5 Nikkor M. Not much use wide open either, but being a modern "normal" tessar rather than wide
angle design, will have comparatively little distortion of falloff a couple stops down - still pretty fast, and a tiny lens. No good for full 4x5. Maybe there are other analogous lens suggestions. Give up some of the angle of view and you could select from 110 to 125/5.6 plasmats perhaps.

When I shoot digital full frame my glass is Minolta and my wide does the same stretch thing, it's just a matter of how close to the edge does this become a problem on these lenses and what apature can I get away with. If I have to stop down to 8-11 I don't think it would be worth it to step to a faster lens over the Nikon f8. I really like the 90mm length and shooting two backs, the 5.6 120s just barely if at all cover 5x7 (most have less coverage then my current 90). I'm tempted by the 120 f8 lenses though or the Schnider, but that's a whole different topic too :).


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[Bob Salomon]

Bob, thank you very much for your detailed reply! By night sky I do largely mean star trails and moon lit landscapes. I'd love to do some "stars as points" but I just don't think that would work on large format. I'm hoping to get away without and expensive center filter sticking to 90 so far. Do you think the faster lenses need it though? The other option is always the Nikon f8, but if the faster lenses can make use of the speed at night it may be worth the cost of weight/size. Normal day shooting I plan to continue shooting around f22 (my "normal" apature).


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Yes, the faster lenses also use center filters for best evenness of illumination across the frame. But, as I mentioned, Nikon never made center filters. You could go to a sharper and faster 90 by going to the Rodenstock Grandagon-N 6.8. Granted, it's only a half stop faster. But it will outperform the one that you are considering without being much, if any, larger and heavier.

[Drew Wiley]

And as I've repeatedly mentioned, the Schneider 82mm CF works absolutely perfectly on the Nikon 90/4.5, confirmed by consistent center to edge densitometer readings on 4x5 film at least, at all the mid stops.

[Bob Salomon]

Won't fit the 90mm f8 that he has been considering.

[Drew Wiley]

Nope. But even with the CF in place, the 90/4.5 would still be slightly brighter to focus. The evenness of the grad density per se seems to be consistent from f/16
down, with a minor falloff penalty somewhat wider. I'd rather just use a 120 or 125 plasmat outright, stopped down a bit of course, unless there were tall trees etc
in the foreground necessitating significant rise to correct for verticals. Some people don't care much about corrections; but the mere fact this thread involves view
camera discussion, means that some do.

[FredrickSummers]

Thank you both again!

@Bob. Thanks for the suggestion, I will add that to the list. What is it about the faster 90s that require center filters as I don't hear anyone talk about using CF on the f8s.

@Drew: I do want the Schnider HM, but they are hard to find and very expensive! Otherwise 120mm I'd be regulated mostly to f8. I currently use a 90-150-210 but slowly moving towed a 90/75-120-180-360 idea now that I have better figured out how I work with LF. I live on the Blue Ridge Parkway, trees (I call them tall, but that's all a matter of perspective) are part of every local photograph :) I use quite a bit of rise often, partly because I'm on the short side.

So do either of you know how the Nikon 4.5 or any of the 5.6 perform wide open or near wide open in relation to star trails?


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[Ted R]

Although this sounds counterintuitive I think you may find that with star trails changing the aperture by a stop or two makes little difference, the stars are point sources and unlike an illuminated surface which has a quantifiable brightness. Before committing to a different lens it might be an idea to do some tests using the lens you have to establish how much difference there is in star trail brightness when the aperture is changed.

[Bob Salomon]

Thank you both again!

@Bob. Thanks for the suggestion, I will add that to the list. What is it about the faster 90s that require center filters as I don't hear anyone talk about using CF on the f8s.

@Drew: I do want the Schnider HM, but they are hard to find and very expensive! Otherwise 120mm I'd be regulated mostly to f8. I currently use a 90-150-210 but slowly moving towed a 90/75-120-180-360 idea now that I have better figured out how I work with LF. I live on the Blue Ridge Parkway, trees (I call them tall, but that's all a matter of perspective) are part of every local photograph :) I use quite a bit of rise often, partly because I'm on the short side.

So do either of you know how the Nikon 4.5 or any of the 5.6 perform wide open or near wide open in relation to star trails?


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All wide angle designs like those from Rodenstock, Schneider, Nikon, Fuji and others all are hot center to edge and all benefit from a center filter.
If you shoot only B&W you can dodge and burn each individual print to even it out. If you shoot chromes you can not dodge and burn. If you like darker corners and edges on wide angle shots you may call this the wide angle effect and decide not to correct it. If you shoot scenes that are naturally darker at the edges and corners, maybe like forest scenes, you might feel that you don't need one. If you shoot wide open skies or beaches that go all the way across the scene you will see the fall off. If you shoot aluminum skyscrapers that fill the height or width of the film you will see the fall off. If you do displacement then you will be positioning the film into the fall off and may get results you don't like without the filter,it is what you want to do and what your sense of quality will accept.n

No large format lens will perform anywhere near optimally wide open or one stop down. They will all be good performers two stops down. So an f8 at 16 will not be as good as a 4.5 stopped down two stops.

[Bob Salomon]

Thank you both again!

@Bob. Thanks for the suggestion, I will add that to the list. What is it about the faster 90s that require center filters as I don't hear anyone talk about using CF on the f8s.

@Drew: I do want the Schnider HM, but they are hard to find and very expensive! Otherwise 120mm I'd be regulated mostly to f8. I currently use a 90-150-210 but slowly moving towed a 90/75-120-180-360 idea now that I have better figured out how I work with LF. I live on the Blue Ridge Parkway, trees (I call them tall, but that's all a matter of perspective) are part of every local photograph :) I use quite a bit of rise often, partly because I'm on the short side.

So do either of you know how the Nikon 4.5 or any of the 5.6 perform wide open or near wide open in relation to star trails?


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Yes, the lenses all benefit from the center filter. That is why they were made. What you read on the internet just means that the poster either doesn't care about the fall off, is ignorant about the fall off or is too cheap to buy the filter. The fall off is there anyway and it is more evident on 45 since the 8.0 covers a small circle then the faster lenses.

[Pfsor]

2) the part that prompts this post: night photography. I have made a few attempts to shoot star trails, but I have yet to get anything with my f8 even wide open, and I got SOME but not very good (which I account largely to technique, but what I got was still very dim) with my fuji 210W 5.6. All my research, the only real difference in these is the coverage and brightness on the GG. What I cannot find though is how these faster 5.6 and 4.5 lenses perform wide open or nearly wide open. Also any real difference between the 5.6 lenses and the nikon 4.5 (one I'm leaning toward)?

Thanks everyone, and feel free to post star/night sky photos taken with any of these lenses as examples :)

For star point light the real aperture size (not the nominal one) is decisive. That is the reason that your 90/8 lens (with a real aperture 11.25mm) gives you a worse result than 210/5,6 lens (with the real aperture size 37.5mm). Star tracks are just traces of star pinpoint light rotating on your film.

I highly suggest to learn the basics of star photography before you venture to buying lenses for that purpose. It pays.

[Corran]

Here's some example images from a thread I made awhile ago and will hopefully revive soon:

http://www.largeformatphotography.info/forum/showthread.php?108317-Startrails!&highlight=startrails

More light is always better. 90mm lenses are cheap these days, so get the 90mm f/4.5 if you find one - why not?

As for the post above, I would invite Pfsor to go ahead and explain further. Considering I can use a 14mm f/2.8 (physical aperture size of 5mm) just fine on 35mm film or my DSLR and capture plenty of stars, more so than any LF lens at a smaller f/# aperture but bigger physical aperture size in my experience, I would say that empirically I must disagree.

Regarding CF, I find them to be unhelpful with night photography when you need all the light you can get. My favorite lens has been a 75mm f/4.5 Biogon or 58mm f/5.6 XL.

[Drew Wiley]

There are entire forums dedicated to amateur astrophotography and analogous night photography. Some of these are pretty interesting and might give some clues.
In general, this is one application where digital capture does better.

[Pfsor]

As for the post above, I would invite Pfsor to go ahead and explain further. Considering I can use a 14mm f/2.8 (physical aperture size of 5mm) just fine on 35mm film or my DSLR and capture plenty of stars, more so than any LF lens at a smaller f/# aperture but bigger physical aperture size in my experience, I would say that empirically I must disagree.


You see, that's one thing that I don't do - pushing people to knowledge they refuse albeit freely available on the net at their fingertip. Go to any astrophotography forum and start your game there, if there is anybody patient enough you can have an interesting experience. Google Pinpoint light source exposure and wonder first.

[Corran]

"Googling" astrophotography gives hundreds of thousands of hits, 98% of which are related to digital photography, as one would expect. This is specifically a LF website, so what I am asking is to better explain and/or give links to better provide information specific to LF shooting of startrails (or whatever topic is at hand). And for your information, I did Google it, several times in fact as you've made the same vague explanation on this forum a number of times, which helps exactly 0 people. Results from my search yielded NO large format specific information nor a concise source of information - in fact I also found sources that contradicted your statement. And as I mentioned, my direct experience also informs me that your assertion is not correct, or at least not wholly correct (there may be variables or considerations you or I assume which were or were not accounted for).

Therefore, I ask again - if you would like to contribute to the greater knowledge base here, specifically with regard to LF photography, perhaps you can further explain rather than pointing vaguely in the direction of another forum that likely has no practicing LF photographers on it.

[Bob Salomon]

"Googling" astrophotography gives hundreds of thousands of hits, 98% of which are related to digital photography, as one would expect. This is specifically a LF website, so what I am asking is to better explain and/or give links to better provide information specific to LF shooting of startrails (or whatever topic is at hand). And for your information, I did Google it, several times in fact as you've made the same vague explanation on this forum a number of times, which helps exactly 0 people. Results from my search yielded NO large format specific information nor a concise source of information - in fact I also found sources that contradicted your statement. And as I mentioned, my direct experience also informs me that your assertion is not correct, or at least not wholly correct (there may be variables or considerations you or I assume which were or were not accounted for).

Therefore, I ask again - if you would like to contribute to the greater knowledge base here, specifically with regard to LF photography, perhaps you can further explain rather than pointing vaguely in the direction of another forum that likely has no practicing LF photographers on it.

Just for my own curiosity, why would doing it on large format require anything other then doing it on medium format or 35mm? Other then the size of the tripod and head.

[Corran]

The assertion that only the physical aperture size matters means that shooting on LF is inherently different from smaller formats due to the differences in relative size of the aperture for a given field of view and f/stop. His statement would then posit that a wide-angle lens on 4x5 like my 58mm XL shot at f/5.6 (~10mm aperture size) should capture more stars than my 14mm f/2.8 (~5mm aperture size) on 35mm or DSLR. I have found this to be incorrect, hence my inquiry.

[StoneNYC]

Listen to Bob mostly and ignore the rest is my suggestion.

However from personal experience f/16 with 100 speed film will only give faint trails, either 400 speed film or f/11 or f/8 would be best.

Film flatness... You're pointing upward, yes temps at night change, but slowly, don't worry about that.

Sharpness wide open... You're shooting star trails, it's not really that much of a concern to be honest.

So most of the "technical" differences with lenses are mostly irrelevant for shooting stars on LF except focusing on the GG.

The weight of each lens is often listed with a quick Google search. Just make a list of the lenses you are considering and their weight.

Also look at filter size, the nikons are cheap but often have HUGE filters on front and rear so that's cost prohibitive if you use color filters. Schneider often have smaller rear filters which at least leaves you an option to have a filter smaller or equal to 77mm where the cost limit for me personally is, anything bigger gets much more costly.

Go shoot 4 sheets tonight with some Acros100 30 minutes each. Use f/8 f/11 f/16 f/22 and find out yourself.

[Drew Wiley]

The shorter the lens, the more film plane issues come into play. Real astro addicts obsess about plane accuracy, and sometimes even add vac backs to MF SLR's.
Just getting a fun shot or two is different.

[FredrickSummers]

For star point light the real aperture size (not the nominal one) is decisive. That is the reason that your 90/8 lens (with a real aperture 11.25mm) gives you a worse result than 210/5,6 lens (with the real aperture size 37.5mm). Star tracks are just traces of star pinpoint light rotating on your film.

I highly suggest to learn the basics of star photography before you venture to buying lenses for that purpose. It pays.

I would challange that as well from experience. I have shot stars with digital, and my best lens was (well, I do still have it) the Minolta 16mm fisheye. I also had a Rokinon 35mm f1.4 which has a huge "real aperture" but, if I stoped it down to f2.8 and the Minolta wide open, even with the same exposure the starts were slightly brighter, but there were more of them (within the same area). I have tried it on a number of lenses and the "real aperture" as you call it was not the determining factors. I also never said the lens was for that purpose, just that it was a consideration of getting faster over slower. If I'm buying a lens I may as well consider all potential uses of it, at least that is my idea. I do have my digital kit (two actually, a6000 for night I normally use my Rokinon 12mm f2 which is quite impressive of a lens) as well as my A99 which a handfull of lenses. I used the a99 this past winter to conduct a test between various 50mm for the mount, and the one with the SMALLEST "real aperture" the 50mm f2.8 macro, actually had the best performance and most visible stars. You do also realize that its not just how bright, but a faster lens will pick up more starts within the given time, right? That, coverage (coverage is normally measured at f22, how bad is fall of at larger apertures), and flare charastics is what I was asking for on that part. Do you have any star/star trail images from large format to share?

[konakoa]

I'd love to do some "stars as points" but I just don't think that would work on large format...

Fredrick, it can be done. I've been working with and using my 4x5 camera for astrophotography for just about a decade now. One of the lenses I keep on hand for the sole purpose of astrophotography is the Nikon 90mm f/4.5. For sharp, pin-point stars across the entire frame, it's no good wide open at 4.5. Sorry. Every time I've tried it wide open stars take on a UFO-like shape in the corners due to diffraction in the lens. However, once stopped down to f/8 the lens is really good, corner to corner. If this also corresponds to the similar but slower 90mm f/8 Nikkor used wide open at f/8 I can't say. I don't have one of those lenses. But I can confirm the 4.5 works nicely once stopped down.

I've never done star trails with the 90mm f/4.5. It may very well be just fine wide open for that.

I've attached two images below. One is a equatorial setup I use for the camera. The other is the result (taken with the Nikon 90mm f/4.5 lens.)

153990 153991

[FredrickSummers]

There are entire forums dedicated to amateur astrophotography and analogous night photography. Some of these are pretty interesting and might give some clues.
In general, this is one application where digital capture does better.

I'm well aware of it and last winter was all over with digital. I still have that, but for one, the fun factor just isn't there when you can take the picture, see how it came out, adjust, and do this though the night until you have what you want. Also I just love using my 4x5, so much so I have kicked around the idea of selling my A99 setup. It may do it better, for points of light, but its just not fun :) Also I think film does star trails better. Leave any digital camera "on" for even minutes, forget hours and the noise would be a killer for the image. Digital star trails are either many 30sec-2min exposures combined together in software OR (and this has become very popular) a single exposure ran though software that "simulates" star trails. It just takes away the fun for me, plus I want to be able to put my star trail image on my light table and just gaze in awe. (Chromes on a light table has not got old yet by a long shot!)


"Googling" astrophotography gives hundreds of thousands of hits, 98% of which are related to digital photography, as one would expect. This is specifically a LF website, so what I am asking is to better explain and/or give links to better provide information specific to LF shooting of startrails (or whatever topic is at hand). And for your information, I did Google it, several times in fact as you've made the same vague explanation on this forum a number of times, which helps exactly 0 people. Results from my search yielded NO large format specific information nor a concise source of information - in fact I also found sources that contradicted your statement. And as I mentioned, my direct experience also informs me that your assertion is not correct, or at least not wholly correct (there may be variables or considerations you or I assume which were or were not accounted for).

Therefore, I ask again - if you would like to contribute to the greater knowledge base here, specifically with regard to LF photography, perhaps you can further explain rather than pointing vaguely in the direction of another forum that likely has no practicing LF photographers on it.

Thank you. There are hudreds of thousands of posts/threads/fourms/blogs/etc on the subject, but only little bits about film and I've only found a few items that include large format, and many topics not addressed and it normally just goes to "experiment".


The assertion that only the physical aperture size matters means that shooting on LF is inherently different from smaller formats due to the differences in relative size of the aperture for a given field of view and f/stop. His statement would then posit that a wide-angle lens on 4x5 like my 58mm XL shot at f/5.6 (~10mm aperture size) should capture more stars than my 14mm f/2.8 (~5mm aperture size) on 35mm or DSLR. I have found this to be incorrect, hence my inquiry.
My experience mirrors yours. My best two night sky lenses on my digital actually have the smaller "real apertures".


Listen to Bob mostly and ignore the rest is my suggestion.

However from personal experience f/16 with 100 speed film will only give faint trails, either 400 speed film or f/11 or f/8 would be best.

Film flatness... You're pointing upward, yes temps at night change, but slowly, don't worry about that.

Sharpness wide open... You're shooting star trails, it's not really that much of a concern to be honest.

So most of the "technical" differences with lenses are mostly irrelevant for shooting stars on LF except focusing on the GG.

The weight of each lens is often listed with a quick Google search. Just make a list of the lenses you are considering and their weight.

Also look at filter size, the nikons are cheap but often have HUGE filters on front and rear so that's cost prohibitive if you use color filters. Schneider often have smaller rear filters which at least leaves you an option to have a filter smaller or equal to 77mm where the cost limit for me personally is, anything bigger gets much more costly.

Go shoot 4 sheets tonight with some Acros100 30 minutes each. Use f/8 f/11 f/16 f/22 and find out yourself.

Thanks Stone, helpful as always :) The nikkor 90 4.5 has an 82mm filter thread. I have the weights down, its just a very different thing to feel them and have them mounted on the camera though. I would love to go tonight and expose some film to the stars, but I haven't seen but a small star here and there for over a week now, we have had 70-90% cloud cover and scattered storms for over a week :( when the storms clear though...



The shorter the lens, the more film plane issues come into play. Real astro addicts obsess about plane accuracy, and sometimes even add vac backs to MF SLR's.
Just getting a fun shot or two is different.

I'm not THAT dedicated. I have a Graphmatic that I will use as it holds the film more firmly and flatter then a normal holder. If I really get serious I'll modify a holder to have a vaccum to the film, wouldn't be all that hard really. Right now I just want to play with it though and see what I get.

Thank you all... And not one image shared yet either :)

[FredrickSummers]

Fredrick, it can be done. I've been working with and using my 4x5 camera for astrophotography for just about a decade now. One of the lenses I keep on hand for the sole purpose of astrophotography is the Nikon 90mm f/4.5. For sharp, pin-point stars across the entire frame, it's no good wide open at 4.5. Sorry. Every time I've tried it wide open stars take on a UFO-like shape in the corners due to diffraction in the lens. However, once stopped down to f/8 the lens is really good, corner to corner. If this also corresponds to the similar but slower 90mm f/8 Nikkor used wide open at f/8 I can't say. I don't have one of those lenses. But I can confirm the 4.5 works nicely once stopped down.

I've never done star trails with the 90mm f/4.5. It may very well be just fine wide open for that.

I've attached two images below. One is a equatorial setup I use for the camera. The other is the result (taken with the Nikon 90mm f/4.5 lens.)

153990 153991

And we have a winner! WOW, that is AMAZING! May I ask which film you use for that? I have been kicking around one of the geo tracking set ups, but I couldn't find much info that wasn't digital specific. It looks like an expensive set up!

Knowing how they perform as points of light tells me all I'd need to know about how it would perform for star trails (I don't think points of light is possible still without the tracking set-up though, not without the ability to get a very high ISO).

[Corran]

What equatorial mount do you use (brand, model)? I've been very close to purchasing a nice German equatorial mount several times but stopped myself. I think I will soon, perhaps also with a telescope to go with.

The UFO or batwing shaped stars in the corners I believe is called coma. Very common on my older fast primes on 35mm when shot wide-open or near. I wonder if the modern aspherical LF lenses have made that issue go away. I have yet to try my Schneider 90mm XL for stars which is my newest wide-angle but I guess it's still not aspherical. The 80mm Super-Symmar is.

[FredrickSummers]

What equatorial mount do you use (brand, model)? I've been very close to purchasing a nice German equatorial mount several times but stopped myself. I think I will soon, perhaps also with a telescope to go with.

The UFO or batwing shaped stars in the corners I believe is called coma. Very common on my older fast primes on 35mm when shot wide-open or near. I wonder if the modern aspherical LF lenses have made that issue go away. I have yet to try my Schneider 90mm XL for stars which is my newest wide-angle but I guess it's still not aspherical. The 80mm Super-Symmar is.

It is Coma, and even many modern lenses have it wide open. Oddly Rokinon/Samyang a low cost and fairly cheap built lenses are the lowest to exhibit it even wide open at 1.4! This is what I was asking about the fast wides. My Fuji 210 didn't appear to have any, but I did such a terrible job trying I doubt I could tell either. They are not as bad doing trails.

On a related note the oddest coma I have had is my Minolta 17-35G wide open (3.5) it's huge and looks like the batman symbols at the far counters!


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[konakoa]

Fredrick, Corran; I’m using two films currently. Both are black and white. One is Fuji Acros. The other is gas hypersensitized Kodak Tech Pan that I started using last year. I had to build the “hypering” system entirely from scratch. For no-fuss results, use Acros. It’s fantastic, fantastic stuff for low light, moonlit landscape, and astrophotography. The image I posted previously was made on Acros.

I used to shoot color, but have put all my efforts into black and white as I can print that in my darkroom. Still, astrophotography on a big color 4x5 transparency can be a beautiful thing. Attached below is one I did many years ago.

The equatorial mount is a Vixen GP2. It’s a nice and simple little mount that sadly isn’t made any more. They go for a few hundred bucks used. It’s perfect for my needs as I wanted something small, compact and not computerized. Another option would be a Losmandy GM-8, (still being produced new) should you be similarly inclined.

Corran, you might be interested to hear I have tried an aspherical lens for stars. A Schneider 150mm XL. Long story short, it also suffers from coma (thanks for the correct term) as well. In the center, perfectly sharp. Stars are nice and round. Go out to the edges of the frame, they’re smeared. I really, really, wanted the 150 XL to perform wide open at 5.6 yet it has the same “UFO” problems as my Nikon 90mm f/4.5. Perhaps moreso. I have a Schenider 150mm HM waiting in the wings to be tried when I can get a break in the weather.

154003

[Corran]

Thanks, I'll take a look at those mounts. Interesting that the asperical lens didn't perform. I've got to try my 90mm and 72mm XL lenses one of these days. Too much rain lately.

I haven't tried shooting startrails with b&w for years. I love the color aspect. I've heard of hypering, that's pretty neat.

[Pfsor]

I would challange that as well from experience. I have shot stars with digital, and my best lens was (well, I do still have it) the Minolta 16mm fisheye. I also had a Rokinon 35mm f1.4 which has a huge "real aperture" but, if I stoped it down to f2.8 and the Minolta wide open, even with the same exposure the starts were slightly brighter, but there were more of them (within the same area). I have tried it on a number of lenses and the "real aperture" as you call it was not the determining factors. I also never said the lens was for that purpose, just that it was a consideration of getting faster over slower. If I'm buying a lens I may as well consider all potential uses of it, at least that is my idea. I do have my digital kit (two actually, a6000 for night I normally use my Rokinon 12mm f2 which is quite impressive of a lens) as well as my A99 which a handfull of lenses. I used the a99 this past winter to conduct a test between various 50mm for the mount, and the one with the SMALLEST "real aperture" the 50mm f2.8 macro, actually had the best performance and most visible stars. You do also realize that its not just how bright, but a faster lens will pick up more starts within the given time, right? That, coverage (coverage is normally measured at f22, how bad is fall of at larger apertures), and flare charastics is what I was asking for on that part. Do you have any star/star trail images from large format to share?

Now when you're comfortably seated in your - my experience is more than the optical science theory - seat go and do yourself a favour. Read the book Wide-field astrophotography by Robert Reeves published by Willmann Bell publisher and learn about the roll of physical and numerical aperture of lenses (yes, even LF lenses, the guy went through it all) in star trails photography, the background night light etc.
But! I warn you - this astrophotographer he too uses the optical science laws you deny. As a starter for this brain washing experience take a look at his www. robertreeves.com website - you can read some chapter of the given book there.

One thing I would discourage you to do though - asking him for his LF lens photographs to prove the optical science laws he talks about. I think it would be too revelatory and he could lose interest in further communication with you.

[Corran]

Now that you are comfortably seated in your - condescending and ultimately unhelpful - seat, I would ask again for you to elaborate and further this discussion, rather than pushing us to purchase a book.

I am here to learn. I welcome further discussion and perhaps the actual optical science theory / equation / whatever. A link to a relevant article would be helpful. I could find nothing on Reeves' site pertaining to this physical vs. f/number aperture thing, even in the first chapter. Sorry if I've missed it, but please feel free to point it out.

[Corran]

There's also the difference in magnification if one goes from 35mm to 4x5 film. Surely this plays into it as well?

I did a simple experiment - 50mm at f/2.8, and then a 135mm at f/8, so roughly the same aperture size like you say, same exposure time and ISO. Equalized the magnification to simulate using different formats, and got this:

50mm:

http://www.oceanstarproductions.com/photosharing/50f28.jpg

135mm:

http://www.oceanstarproductions.com/photosharing/135f8.jpg

Sure both have the brighter stars but some of the dimmer stars are gone in the 135mm photo and they are all dimmer in general. Factoring in reciprocity, it would seem the dimmest stars would start to drop off even faster due to not registering on the film before it moved. Again, I am interested in learning and I would like to read more if you have a source of some kind.

[Pfsor]

Again, I am interested in learning and I would like to read more if you have a source of some kind.

Why not trying the book Wide-field astrophotography by R. Reeves I told you about?

[Corran]

You implied all kinds of sources were just a Google search away. Why not provide a link to the specific information/explanation in question? It's really fairly simple. Are you here to contribute meaningful discussion and discourse or just sell books?

[Pfsor]

Are you here to contribute meaningful discussion and discourse or just sell books?

Sorry I told you about the book. On the other hand, you don't need to buy it. Borrowing it in a library would do too. Sorry again about it. I won't do it anymore, I promise.

[Pfsor]

One more try for those who want to learn about pinpoint star exposure -

http://www.kodak.com/global/en/consumer/products/techInfo/p150/p150a.shtml

[Pfsor]

One more try for those who did not learn from the first try -
https://books.google.ch/books?id=IIPuBwAAQBAJ&pg=PT23&lpg=PT23&dq=astrophotography+exposure+time&source=bl&ots=Ro8pu8v1BM&sig=wgZGC71jxIAaaVX-vpag9VeVOkI&hl=en&sa=X&ved=0ahUKEwjm4raJl83OAhUGuxQKHQclA444ChDoAQhXMAw#v=onepage&q=astrophotography%20exposure%20time&f=false

[neil poulsen]

I have a couple of questions . . .


6 all of them are optimized for f22 and are diffraction limited at f22. For star tracks that is probably a moot point. But are you only going to shoot star tracks? . . .

My understanding is that, once one closes the aperture of an f22 diffraction limited lens beyond f22, sharpness decreases in the plane of focus. In other words, f22 is the point at which decreasing the aperture further no longer improves sharpness in this plane. (Is this correct?)

To a second question, what would be involved in designing a lens that had better than f22 diffraction limited performance? What would be the trade-off?


2 because of the larger circle the fall off starts further out from the center so it is less then the slower lens over the same film area. . .

To what degree is fall off caused by the off-axis angle becoming greater as the image gets closer to the edge of the film, versus the construction of the lens?

[Pfsor]

One more try for those who like a "rather verbose" variant on the same theme.
http://petapixel.com/2014/01/29/picking-great-lens-milky-way-photography/

[FredrickSummers]

Now when you're comfortably seated in your - my experience is more than the optical science theory - seat go and do yourself a favour. Read the book Wide-field astrophotography by Robert Reeves published by Willmann Bell publisher and learn about the roll of physical and numerical aperture of lenses (yes, even LF lenses, the guy went through it all) in star trails photography, the background night light etc.
But! I warn you - this astrophotographer he too uses the optical science laws you deny. As a starter for this brain washing experience take a look at his www. robertreeves.com website - you can read some chapter of the given book there.

One thing I would discourage you to do though - asking him for his LF lens photographs to prove the optical science laws he talks about. I think it would be too revelatory and he could lose interest in further communication with you.

Easy with the hostility there. Thanks for the suggestion of the book, I will check it out on my next book run. I don't care enough to break it down into the science, stars can make some very cool landscape photos, that's the extent I care about right now. I didn't start the thread to become a debate of aperture vs "real aperture". Thank you for your contribution thus far, but the hostility is not needed.

Also thanks for the links, I'll check them out when I get more 5 minutes free :(


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[FredrickSummers]

Yes, the faster lenses also use center filters for best evenness of illumination across the frame. But, as I mentioned, Nikon never made center filters. You could go to a sharper and faster 90 by going to the Rodenstock Grandagon-N 6.8. Granted, it's only a half stop faster. But it will outperform the one that you are considering without being much, if any, larger and heavier.

Bob, I always value your opinion, and thank you again. I assume by sharper and faster you mean as compared to the Nikon 90 f8? What makes the rodenstock sharper? I thought all the large format lenses were more or less the same for sharpness, etc? I'm not doubting you, just asking.


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[FredrickSummers]

How about 75s, I assume they would prefer very similar, but 24mm is the popular astrophotograpy focal length and also one I really like/liked. If I'm going to change to a different wide may as well consider those. They are all pretty fast too!


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[Pfsor]

From one who learned the laws of optics and does some astrophotography with his LF equipment - http://www.cloudynights.com/documents/large.pdf

[Drew Wiley]

Fun stuff. If I had the money and time for this, I've got a friend who is a noted astrophysicist. The only problem is, those kinds of people have a very very different definition of "large format" and "tripods" than we do.

[Bob Salomon]

Bob, I always value your opinion, and thank you again. I assume by sharper and faster you mean as compared to the Nikon 90 f8? What makes the rodenstock sharper? I thought all the large format lenses were more or less the same for sharpness, etc? I'm not doubting you, just asking.


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Best is to get the curves, Dan Fromm probably has them, and compare MTF, over the same area and f stop, distortion, color, fall off between them. Or go rent or borrow them and do a comparison.

Or maybe ask yourself why say Sinar only used Rodenstock lenses to brand with their own name. Or maybe check what Alpa might have available in test results on thei site.

[EdSawyer]

FrederickSummers, you would be remiss in not considering the Nikkor 90/8. it's easily the best 90mm made for 4x5, by a large margin, and is pretty well optimized even at f/11. Empirical test results bear this out: http://www.hevanet.com/cperez/testing.html , and it has the same image circle as the larger Nikkor 90/4.5.

[FredrickSummers]

Best is to get the curves, Dan Fromm probably has them, and compare MTF, over the same area and f stop, distortion, color, fall off between them. Or go rent or borrow them and do a comparison.

Or maybe ask yourself why say Sinar only used Rodenstock lenses to brand with their own name. Or maybe check what Alpa might have available in test results on thei site.

Thanks Bob. I've only been able to find two places online so far that rent LF lenses and their section is limited. I do plan to rent a few.


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[Drew Wiley]

Ed, I think you'd find there are quite a few serious users who would disagree with you, and prefer the 4.5 for its optics and not merely speed. Some half-baked
web evaluation means zero, and is hardly objective proof. Then somebody else is going to cite a Biogon 90 (a tank with limited image circle, but rectilinear),
a Grandagon, Fuji, whatever. The cat has been out of the bag a long time, and all these primary manufacturers knew how to do it right.

[Dan Fromm]

Best is to get the curves, Dan Fromm probably has them, and compare MTF, over the same area and f stop, distortion, color, fall off between them. Or go rent or borrow them and do a comparison.

Or maybe ask yourself why say Sinar only used Rodenstock lenses to brand with their own name. Or maybe check what Alpa might have available in test results on thei site.

Bob, thanks to you I've been able to put Rodenstock brochures with MTF, illumination and distortion curves up on my One Drive. My list of links to useful sources of information, including the R'stock brochures you lent me, is here: https://onedrive.live.com/redir?resid=8D71BC33C77D1008!1005&authkey=!ACp3Kf30SHN3MwY&ithint=file%2cdocx I don't recall whether any of the Schneider brochures in the archived old Schneider site on the list have curves.

[Drew Wiley]

I've pulled up Schneider curves online. Can't recall them ever in a brochure. I still have the relevant Rodenstock brochure, and have consulted it numerous times.

[Corran]

One more try for those who want to learn about pinpoint star exposure -

http://www.kodak.com/global/en/consumer/products/techInfo/p150/p150a.shtml

Thank you for posting actual links to articles. I don't know about your library but unfortunately none of the libraries I've ever been to contain obscure technical photography manuals.

Anyway, reading this specific Kodak brochure and some of the other links you provided, it does talk about pinpoint light sources. I notice that most of the times this is brought up, such as here, it is in specific reference to telescopes.

Reading this it seems to me that this is more important for tracking the pinpoint light source and not so much for startrails, because what it boils down to is that the larger physical aperture at a given f/stop on longer lenses also means that the movement of the star is faster on film.

Given this, imagine two cameras - one with 35mm film and one with 4x5, both with lenses that correspond to roughly the same field of view on their format. So perhaps a 15mm lens on 35mm and 58mm on 4x5. Both shot at the same aperture, obviously the 58mm lens has a larger physical aperture opening. What is different also though is that the star moves faster on the film on the 4x5 shot due to the longer focal length. It seems to me that the phenomenon you describe equals out when you shoot a larger format due to the differences in focal length for the same apparent FoV. This would explain why shooting on 35mm or digital, stars look just as bright at a correspondingly smaller physical aperture size, because they are exposing the film longer at a given time due to shorter focal length. However for a camera on an equatorial mount, it would make sense to use the largest objective one had, as the movement of the star is negated. Therefore, while you are correct, it does not make sense to discuss this across formats and huge differences in focal length as there are very different uses for a given focal length between 35mm and 4x5.

[Pfsor]

The OP did not want to discuss 35mm format at all.
I explained to him that there is an important difference he neglects in the lenses he mentioned and that this importance directly influences his astrophotography.
Now, what you would like or not to discuss is entirely your problem. Capito?

[Corran]

It's unfortunate that your hostility and attitude hinders discussion and learning. If you want to help anybody I recommend you consider not being a jerk.

I had some more written here but it's clear you don't want to have a discussion so never mind. The point is that focal length is a more important consideration to shooting startrails due to composition/framing than physical aperture size. Widefield shooting with a tracking mount, yeah you've got a point, but that's not what OP is doing it sounds like.

[Pfsor]

I take it you have learned about the importance of the real aperture size in astrophotography, even if not without a pain.

[Corran]

Except it has no bearing for startrails, which was my point. Thank you for sharing.

[Pfsor]

Except it has no bearing for startrails, which was my point. Thank you for sharing.

You're very much mistaken because the real aperture size has a lot to do with star trails - remember, star trails are just moved pinpoint sources of light registered on the film. And pinpoint sources are registered on the film in the direct dependence on the real aperture size. You seem to be particularly inapt when it comes to learn about optical laws. Why is that?

[StoneNYC]

You can lead a horse to water...

Can't we all just get along?

[Corran]

Stone, do you have anything actually relevant to add? Or just more useless banter with thinly-veiled insults? As for getting along, the hostility is from Pfsor. It is unfortunate he can not have a civil discussion.

From the very beginning my question to him has been for more explanation. The simple fact here is you can't just boil down the entire image to just the physical aperture size. For one, the focal length is integral to the composition that the photographer chooses. Therefore I am never going to go out to make a photo with a 90mm lens and then say "oh, well I'll use this 300mm f/4.5 instead because the hole is bigger!" because that lens would be so much different and I couldn't include the landscape foreground as I intend. I assume, perhaps wrongly, that most are shooting startrails with a foreground interest. If not, the FL still determines how many stars are in the frame. And as I've already said, if one is shooting on a tracking mount, it would be much more important. This entire thread was predicated on startrails from a stationary camera though.

Secondly, and more importantly, is the movement of the stars on the film as Pfsor has just mentioned. Consider a 90mm lens and a 180mm lens. Both are set at f/8. The physical aperture size of the 90mm lens is about 11mm, while the 180mm lens is at about 22mm. So the 180mm lens gets more light. Okay - however, the stars are moving across the film at a relatively faster rate due to the longer focal length. What I am asking here is, doesn't this then negate the larger amount of light collected due to the larger aperture size? Surely there must be a difference. This is why the commonly cited "Rule of 600" is used - to determine how long an exposure one can shoot (on 35mm or a DSLR generally) before the star starts to trail. The longer the lens, the shorter you can shoot before a trail starts to show up (and this is also dependent on where you aim the camera relative to the poles). Anyway, this change in speed of the star vs. the focal length explains why you can use shorter lenses on smaller formats and still get plenty of startrails. It seems to me this movement is the source of the confusion and why you can't boil down the entire exposure into one simple concept.

I have still yet to see any kind of formula or something like that in any of the links provided to help calculate this. I am asking these questions and posing these discussions to help further both my understanding and to provide a broader base of information and experience to the forum. I find it really unfortunate that Pfsor chose to instead make this some sort of battle instead of a discussion to further understanding.

[StoneNYC]

There's tech info and there's artistic choice. The ideals of each don't always line up.

My statement above was supposed to be helpful, meaning, you can be given all the info, but you can't be forced to use it, you can and will pick and choose what info you want to utilize.

I think Pfsor is just giving the info. Like use a longer lens with wider physical aperture doesn't mean you have to use it, it's just useful to know and understand it, and then you can choose to use it or not.

You're both kinda just being argumentative and ignoring each other's perspective. It takes two to tango.

The thing I want to understand is why my CF on my 150 SS XL isn't affective wide open, I'm not sure I understood why. If I want to use that with some 8x10 Velvia50 or 8x10 Provia100f for a wide view, why can't I shoot at f/5.6 or f/8 to reduce coma, and it won't truly work effectively? Why?

[Bob Salomon]

There's tech info and there's artistic choice. The ideals of each don't always line up.

My statement above was supposed to be helpful, meaning, you can be given all the info, but you can't be forced to use it, you can and will pick and choose what info you want to utilize.

I think Pfsor is just giving the info. Like use a longer lens with wider physical aperture doesn't mean you have to use it, it's just useful to know and understand it, and then you can choose to use it or not.

You're both kinda just being argumentative and ignoring each other's perspective. It takes two to tango.

The thing I want to understand is why my CF on my 150 SS XL isn't affective wide open, I'm not sure I understood why. If I want to use that with some 8x10 Velvia50 or 8x10 Provia100f for a wide view, why can't I shoot at f/5.6 or f/8 to reduce coma, and it won't truly work effectively? Why?

Because the film won't see the effect of a CF unless you are stopped down 2 or more stops. It is how they work.

[StoneNYC]

Because the film won't see the effect of a CF unless you are stopped down 2 or more stops. It is how they work.

Thanks Bob, I mean, why? As in the science behind it.

Also, how far out does it actually affect? Like, the 150 covers 11x14, but if you use an 8x10 or 4x5 will it matter more or less?

But more importantly, "it's how they work" doesn't answer WHY. Because I physically see a reduction in the visible light when I add the filter, even wide open, so why does it need to be stopped down? What changes when stopped down that it won't work wide open, is there a "TOO SMALL" aperture on the other end that also doesn't have an affect?

[Bob Salomon]

Thanks Bob, I mean, why? As in the science behind it.

Also, how far out does it actually affect? Like, the 150 covers 11x14, but if you use an 8x10 or 4x5 will it matter more or less?

But more importantly, "it's how they work" doesn't answer WHY. Because I physically see a reduction in the visible light when I add the filter, even wide open, so why does it need to be stopped down? What changes when stopped down that it won't work wide open, is there a "TOO SMALL" aperture on the other end that also doesn't have an affect?

The fall off begins about ⅓rd out from the center and increases to the edge.

Read page 26 of the following, it is the digital lens CF works the same way and for the same reason as the analog lens CF except the way that they are made by Rodenstock are different since digital is more demanding then film.

http://www.rodenstock-photo.com/Archiv/Objektive%20digitale%20Fotografie%20e.pdf

Unfortunately, in the past, Rodenstock did have a brochure specifically for center filters but no longer is on their web site.

You might check to see if Dan Fromm has a copy on his site, if he does it would be for the earlier version and not the current manufacturing system.

[StoneNYC]

The fall off begins about ⅓rd out from the center and increases to the edge.

Read page 26 of the following, it is the digital lens CF works the same way and for the same reason as the analog lens CF except the way that they are made by Rodenstock are different since digital is more demanding then film.

http://www.rodenstock-photo.com/Archiv/Objektive%20digitale%20Fotografie%20e.pdf

Unfortunately, in the past, Rodenstock did have a brochure specifically for center filters but no longer is on their web site.

You might check to see if Dan Fromm has a copy on his site, if he does it would be for the earlier version and not the current manufacturing system.

Thanks Bob!