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explain like I'm 5......... 90mm lenses
Hey there,
I'm new to the LF game and I have a few questions about 90mm lenses.
As far as I can tell there are lenses like the Fujinon f/8 which are huge, and lenses like the Schneider f/6.8 which is tiny.......and faster........and cheaper.
Are the small Schneider-type lenses really muddy? Presumably there's a reason people pay more for a bigger and slower lens......are they way sharper?
Looking into buying a 90mm but I want to know what I'm doing.
Benno
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Re: explain like I'm 5......... 90mm lenses
Your wish is my command!
Go potty, take a nap, eat a snack, and then get Mommy to read you some stories from the lens section of https://www.largeformatphotography.info/
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Re: explain like I'm 5......... 90mm lenses
Jes' plain Angulons have less coverage than modern wasp-waisted w/a lenses of the same focal length. By the way, there's also a 90/6.8 Raptar, different design than the jes' plain Angulon, same performance.
If you don't need movements the 90/6.8ers will do. If you need movements, they won't.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Dan Fromm
Jes' plain Angulons have less coverage than modern wasp-waisted w/a lenses of the same focal length. By the way, there's also a 90/6.8 Raptar, different design than the jes' plain Angulon, same performance.
If you don't need movements the 90/6.8ers will do. If you need movements, they won't.
And the 90mm WA Geragon.
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Re: explain like I'm 5......... 90mm lenses
In this instance, two things make lenses bigger: Speed (maximum aperture) and coverage (size of image circle). This latter is a result of lens design: more and bigger elements are needed to do the job.
So in this focal length group, you've got 90mm f/6.8 lenses (a couple different designs, as Dan mentions, but similar performance) that just barely make an image circle large enough to cover all of a 4x5-inch piece of film. Some names in this category: Angulon (not Super Angulon) and Raptar (and a Wide Field Ektar f/6.3: not a 90mm, but rather a 100mm lens, which is in the same general category.)
Then you've got the bigger lenses in the 90mm category, which have substantially larger image circles and will allow generous movements (think lots of front rise when photographing architecture, etc.). These get divided into two sub-groups depending on speed.
For example, you have the large Super Angulon 90mm F/8 and the even larger Super Angulon 90mm f/5.6. The latter is faster by a stop plus has more coverage.
Continuing in this same vein, you have: Fujinon and Nikkor SW series lenses in f/8 and f/5.6. Again the faster lens is bigger and has more coverage. Rodenstock calls their wide lenses Grandagons and they come in f/6.8 and f/4.5. Same thing as above, just both lenses are a bit faster.
Note that a lens design series can have many focal lengths. E.g., the Schneider Super Angulons came not only in 90mm focal lengths, but also 65mm, 75mm, 120mm etc. (There's also the more modern and slightly-better performing Super Angulon XL series with a different set of focal lengths: 38mm, 47mm, 72mm and two versions of our old standby, 90mm). Other brands are similar.
Find a pdf of a large-format lens brochure or two online and peruse them. That'll clear up any confusion.
Hope this helps,
Doremus
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Re: explain like I'm 5......... 90mm lenses
Ok, thanks! Looks like I need one of the hourglass lenses, hmm.............
Thanks to all for you input!
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Re: explain like I'm 5......... 90mm lenses
My wide angle lens is a Super Angulon with a center filter. I use it on 4 x 5 (Technika) and 5 x 7 (with not much in the way of movements - pretty much on center only - but it's really wide!)
On the longer end the Nikon sets are great - I have the 360 - 500 - 720 set with the 720 being too long for the Technika and at f/16 a bit dim, but the set is lighter than carrying three separate lenses and the image quality is excellent.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
BrianShaw
I just spit tea out my nose!
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
BennoLF
....Are the small Schneider-type lenses really muddy?
....
No. absolutely not. In fact when stopped down to f/8 or f/11, the 90mm f/6.8 Angulon is very sharp indeed. It is a very compact and light weight lens - a favorite of backpackers and Photo Journalists. They do not allow much, if any movement on 4x5 and they might be a little soft in the corners...oh, and most are now a least 40~50 years old (?) which means that shutters will also be old and in need of service.
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Re: explain like I'm 5......... 90mm lenses
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Re: explain like I'm 5......... 90mm lenses
I really like the Rodenstock 6,8 lenses, as a good compromise between the dim f/8 lenses and the big f/5.6 lenses. Of the f/8 lenses, the Nikon SW has the most coverage.
Wide angle lenses can be hard to use as they get dim near the edges of the ground glass. That can be a particular problem when photographing inside.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
BradS
No. absolutely not. In fact when stopped down to f/8 or f/11, the 90mm f/6.8 Angulon is very sharp indeed. It is a very compact and light weight lens - a favorite of backpackers and Photo Journalists. They do not allow much, if any movement on 4x5 and they might be a little soft in the corners...oh, and most are now a least 40~50 years old (?) which means that shutters will also be old and in need of service.
Schneider designed it for 9x12 cm, not 4x5” so for many it is not a good performer edge to edge.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Bob Salomon
Schneider designed it for 9x12 cm, not 4x5” so for many it is not a good performer edge to edge.
Just part of the beauty of this little optic.
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Re: explain like I'm 5......... 90mm lenses
The Nikkor 90mm f/8 is *the* 90mm 4x5 lens. All else are not as good.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
EdSawyer
The Nikkor 90mm f/8 is *the* 90mm 4x5 lens. All else are not as good.
Why?
As an aside, I'm just getting into 4x5 and have a 150mm now. I shoot mainly landscapes. So what would be a good selection for a 90mm?
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Re: explain like I'm 5......... 90mm lenses
The possible rational for the SW Nikkor 90mm f8 being tops.... small size with a LARGE image circle.. that is about it.
Tops completely depends on the image making needs. IMO, majority of modern 90mm wide angle lenses with a full aperture of f4.5 to f5.6 are FAR more similar than different. Exception being the Schneider Super Angulon XL with the largest image circle of this group... it is also physically the largest lens of the group.
IMO, there is no "best" there is only what works best for a given need. Frankly, the image circle obsession ... an obsession. Fact is, how much image circle is needed completely depends on the image to be made with any given lens (camera movements). Some images require zero camera movement while other cannot not be made without pushing camera & lens to it's very limits. Larger image circle is not always a good thing as the un-used light from the image circle projected inside the bellows will reflect off the bellows which reduces contrast to varying degrees. As with most stuff, it's a trade off.
Taking aperture figures into this. Most modern wide angle lenses work GOOD at f11 and smaller (there are exceptions like the 75mm f4.5 Biogon, 35mm-45mm-55mm f4.5 green stripe Grandagon). Image circle size increases as the lens aperture deceases, BUT the possible optical resolution decreases due to diffraction.. Again, this is another trade off.
Bernice
Quote:
Originally Posted by
Alan Klein
Why?
As an aside, I'm just getting into 4x5 and have a 150mm now. I shoot mainly landscapes. So what would be a good selection for a 90mm?
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
EdSawyer
The Nikkor 90mm f/8 is *the* 90mm 4x5 lens. All else are not as good.
+1
But any cheap modern 90mm lens will be more than good enough for most. I've used most all of them and seen little to no difference.
90mm Angulon and similar have soft corners and no extra IC.
90mm f/8 lenses from the Big 4 are all mostly the same, Nikkor is a standout though with slightly more IC. All have 67mm filters IIRC.
90mm f/4.5 or f/5.6 are bigger and take larger filters at 82mm (Rodenstock f/6.8 model is an interesting in-between with 67mm filters, as mentioned by Peter).
90mm XL is massive but the no-compromise option (95mm filters).
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Re: explain like I'm 5......... 90mm lenses
Modest magnification loupe (4x to 7x) tilted at an angle towards the center of the lens while viewing the edge of the ground glass image. Fresnel lens will not help you here, it can make assessing the image FAR more difficult.
This is the routine when using a 72mm Super Angulon XL with 5x7_13x18cm interior images. More challenging if this is done a night with the indoor space illuminated with dim light bulbs.
Bernice
Quote:
Originally Posted by
Peter De Smidt
Wide angle lenses can be hard to use as they get dim near the edges of the ground glass. That can be a particular problem when photographing inside.
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Re: explain like I'm 5......... 90mm lenses
I have to throw another one in the ring: the 90mm Ilex-Calumet Wide Field Caltar f/8 (AKA 90mm Ilex Acugon). It lives in the 5x7 kit as it beat out the 90mm f/8 Super Angulon which is in the 4x5 kit. The 90mm Angulon is on the Travelwide.
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Re: explain like I'm 5......... 90mm lenses
Lots of good suggestions in this thread. I'll through in my own qualitative comments, FWIW, based upon my actual testing of the following 90mm UWA lenses that I have for different sets of 4x5 and 5x7 gear, along with 75mm and 105mm Fujinon UWA lenses.
90mm/5.6 Fujinon SWD - very sharp, multi-coated, but really big (82mm filter size), heavy and suitable only for fairly static photography. It's an 8 element UWA with 105 degree coverage that works well with 5x7. However, the 90mm/f8 Nikkor does just as well up to 5x7 and in a significantly smaller package.
90mm/8 Nikkor - sharpest lens of the lot by a small margin and with a 67mm filter size. The 235mm/105 degree image circle/coverage is large enough for some movement on 5x7, and it's sufficiently small/light for backpacking My personal preference.
90mm wide angle Dagor - very, very small yet does a very nice job on 4x5. Downside - it's currently as expensive or more expensive than the Nikkor 90/8 on the used market and the shutter will probably require a CLA. Still, as a tiny 4x5 backpack lens, it's great. You can sort of eke out usable 5x7 coverage at very small apertures, but that's marginal.
90mm/6.8 Angulon I apparently have a good factory-coated later copy and it's decent at small apertures, but still seems softer and less contrasty than the similar 90mm Wide Angle Dagor. My least favorite.
Additional comparisons in nearby focal lengths:
75mm/8 Fujinon This is the first version of the SW series, with the inside lettering and single-coated. It's surprisingly sharp and small (58mm filters, I seem to recall). Some movement on 4x5 is possible as the image circle is about 180mm. It's Fujinon's equivalent to the original Super Angulon in terms of 6/4 design. This might be a good alternative to a 90mm UWA - you can always crop a bit or move in closer if you want a tighter composition.
105mm/8 Fujinon NSW This is a later UWA design using 6 air-spaced elements in six groups, multicoating, and lettering on lens barrel outside. It's extremely sharp and my preferred 5x7 UWA, but is overkill on 4x5 as it is a 77mm filter size lens.
The good performance of the later 105mm NSW Fujinon 6/6 design and the earlier 75mm/f8 6/4 design suggests that later NSW models of the Fujinon 90/8 would have similarly good 4x5 performance in a smaller, less expensive package. I did not get one because the 90/8 Fujinon does not cover 5x7.
Fujinon had a known commitment to good quality control for their LF lenses. Of the 11 Fujinon lenses that I purchased on the usedmarket, I have not had a single bad one. Qualitatively, I would generalize that one or two were average to somewhat above average while the rest were excellent or better.
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Re: explain like I'm 5......... 90mm lenses
Jpseph, I have a Chamonix 4x5. How does the f/8 rating of the Nikkor 90mm rate as far as ability to see the GG that has a fresnel lens? Would this be a good selection for 4x5?
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Re: explain like I'm 5......... 90mm lenses
Why do 75mm and 90mm have the same 105 degree angle of coverage based on this sheet from references in this forum?
https://www.largeformatphotography.i...s/LF4x5in.html
Where can you get dimension spec (length width etc) for all lenses?
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Re: explain like I'm 5......... 90mm lenses
Th aforementioned sheet of lenses shows center filter prices for many of the lenses. WIll I need to buy this separately if listed? I shoot Tmax BW and color slide film.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Alan Klein
That’s the angle of illumination, not the angle of coverage. The first determines how large a diameter the lens covers. The second is how wide the lens is on the format you are using. So an 105° coverage lens has a larger circle of illumination then an 80° coverage lens.
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Re: explain like I'm 5......... 90mm lenses
Look at this image made with a tiny lens
I have one of these lenses and plan to use it more
https://www.largeformatphotography.i...=1#post1535231
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Re: explain like I'm 5......... 90mm lenses
Hmm. Randy, if you want tiny, you want a 90/14 Perigraphe VIa. Compared to it the 90/6.8ers are monstrous. However, the Perigraphe is in barrel. Stuffed into the front of an Ilex #3 -- that's how I use mine -- it isn't quite so small. But with a Speed Graphic, ...
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Tin Can
It may be instructive to consider the movements used here. With some front rise to correct keystoning, the bottom of the lens' image circle is being cut off, showing good sharpness therefore in the lower area of the image. In opposition, the poorer area of the image is being almost completely hidden in a dark featureless sky. There may even be some vignetting we don't see. This image is an example of an absolute best-case scenario for the Optar.
In other scenarios the corner areas may be unsuitable. I also have one negative that I noticed better performance than expected in the bottom area which I think is indicative of field curvature, which in some cases is actually helpful.
Other than some "golden" samples, I would guess any and all small f/6.8 90mm lenses of the Angulon/Optar variety would perform relatively worse than newer and larger lenses, but that may very well not matter to some and for some applications.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Alan Klein
The Fujinon f/8 lenses are 100 degree angle of coverage - the angle of coverage is inherent in the design of a particular lens. For a given angle of coverage, the diameter of the image circle increases linearly with the focal length. Assuming no mechanical vignetting, to calculate the diameter of the usably sharp image circle, a good approximation is 2 x the tangent of (angle of coverage/2) X focal length.
Lens data and manufacturer specs are basically found throughout the Internet - there are very few new LF lenses being manufactured. This forum is a good place to start, particularly the sticky items at the top. Dan Fromm's guide to lens data can be found on this forum and is likely the best starting point.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Alan Klein
i have not found that an f/8 lens is significantly more difficult to view on the ground glass, but size and bulky may be of greater operational importance to some. On a smaller wooden camera ( I have a Nagaoka 4x5 myself), the bulk and weight of an f/5.6 may be too much for the front standard or simply too large and heavy to be comfortable in operational use. Your mileage may vary. I do find that a fresnel lens is very helpful at the corners.
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Re: explain like I'm 5......... 90mm lenses
I just got an idea. I have an f/5.6 150mm. I'll turn the aperture down to f/8 while viewing and see how bright it is to help make a decision about my next lens.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Alan Klein
I just got an idea. I have an f/5.6 150mm. I'll turn the aperture down to f/8 while viewing and see how bright it is to help make a decision about my next lens.
I did that with my 90/5.6 and decided that if I used it once more I’d by a 90/8 first. :)
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Re: explain like I'm 5......... 90mm lenses
Right now my 90mm Optar in well working shutter is still on my plastic camera many here bought
I use it handheld at 5' using a prefocus distance and a wire finder............with flashbulbs
The Optar is just a lens option, but I will point out, my camera didn't break the weak point with a far heavier lens...
I experiment a lot, and am definetly not seeking AA magnificence, nor his tripod holes
I'm a good time guy! at least I used to be...:(
Dan, I am sure you could suggest far more exotic lenses that I will never find, buy or even want
I have four 90's....
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Alan Klein
I just got an idea. I have an f/5.6 150mm. I'll turn the aperture down to f/8 while viewing and see how bright it is to help make a decision about my next lens.
Wait but doesn't this not work? f/8 on a 90mm lens is a lesser transmittance than a a f/8 150mm, because the 150mm lens is a narrower FOV.
Both transmit the same total amount of light but with a smaller angle the 150mm is brighter per any given area. Or at least so the astro shooters tell me. Something about 'clear aperture size'
https://petapixel.com/2014/01/29/pic...y-photography/ look about 1/3 of the way down.
Am I talking crazy?
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Re: explain like I'm 5......... 90mm lenses
Don't forget to factor in 1 -2 stops falloff at the edges.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
BennoLF
Wait but doesn't this not work? f/8 on a 90mm lens is a lesser transmittance than a a f/8 150mm, because the 150mm lens is a narrower FOV.
Both transmit the same
total amount of light but with a smaller angle the 150mm is brighter
per any given area. Or at least so the astro shooters tell me. Something about 'clear aperture size'
https://petapixel.com/2014/01/29/pic...y-photography/ look about 1/3 of the way down.
Am I talking crazy?
You can always compromise between 5.6 and 8.0 with the 90mm 6.8 Grandagon N or the Grandagon.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Tin Can
Dan, I am sure you could suggest far more exotic lenses that I will never find, buy or even want.
Look for 90/14 Perigraphes and you will find. I just checked on ebay.com, 12 on offer. There should be others on ebay.fr.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Alan Klein
Hi, Alan
I checked the chart and it would appear that the series you compared are mismatched. The chart correctly shows the f/8 Fujinon SW wide angle lenses as 100 degrees coverage and the 90mm /5.6 SWD ( as in Deluxe) series correctly at 105 degrees. To my knowledge, the Nikkor 90/f8 is the only smaller f/8 modern ultra wide angle lens to have a 105 degree angle of coverage. Usually, the f/8 lenses have 100 degree coverage and the f/5.6 lenses have 105 degree coverage.
My suggestion is that you try to get an idea about relative sizes, weights, and ergonomics before spending a lot of money for am f/5.6 Ultra Wide Angle (UWA) lens that's too large and heavy to be usable on a field camera or that needs an expensive, hard-to-find center filter to be usable. I have both f/8 and f/5.6 UWA lenses. The relatively compact 75mm and 90mm f/8 lenses go along with most photo outings while the f/5.6 is admired and then put away in a dark drawer for yet another day.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Joseph Kashi
Hi, Alan
I checked the chart and it would appear that the series you compared are mismatched. The chart correctly shows the f/8 Fujinon SW wide angle lenses as 100 degrees coverage and the 90mm /5.6 SWD ( as in Deluxe) series correctly at 105 degrees. To my knowledge, the Nikkor 90/f8 is the only smaller f/8 modern ultra wide angle lens to have a 105 degree angle of coverage. Usually, the f/8 lenses have 100 degree coverage and the f/5.6 lenses have 105 degree coverage.
My suggestion is that you try to get an idea about relative sizes, weights, and ergonomics before spending a lot of money for am f/5.6 Ultra Wide Angle (UWA) lens that's too large and heavy to be usable on a field camera or that needs an expensive, hard-to-find center filter to be usable. I have both f/8 and f/5.6 UWA lenses. The relatively compact 75mm and 90mm f/8 lenses go along with most photo outings while the f/5.6 is admired and then put away in a dark drawer for yet another day.
The 90mm 6.8 Grandagon and Grandagon N cover 102° more then most 8.0 lenses and 3° less then the 5.6 and 4.5 90s.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Joseph Kashi
My suggestion is that you try to get an idea about relative sizes, weights, and ergonomics before spending a lot of money for am f/5.6 Ultra Wide Angle (UWA) lens that's too large and heavy to be usable on a field camera or that needs an expensive, hard-to-find center filter to be usable.
Joseph, optical vignetting (the dread cos^4) afflects all lenses equally. There've been many discussions about when a center filter is necessary. To the extent that there's a consensus, it is that 90 mm is the shortest focal length that can be used on 4x5 without a CF.
When a 90 mm lens is shot straight ahead, i.e., with no movements, the very corners of the 4x5 frame will be 1.5 stops down from the center. Most photographers find this tolerable.
Benno, if this drop of is more than you can tolerate -- it will be if you shoot reversal film -- you should be aware that there are no center filters for the small thin inexpensive 90s you asked about. There are CFs for the modern wasp-waisted ones. To learn more, especially about CFs for lenses whose manufacturers never offered CFs, read my article on the French LF forum. http://www.galerie-photo.com/center-...at-lenses.html
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Re: explain like I'm 5......... 90mm lenses
What were the "test" methods used to determine the SW Nikkor 90mm f8 was the "sharpest" of the lot?
*Camera used, film used, how was the film processed, subject & lighting conditions used, criteria used, how many representative sample(s) of SW Nikkor 90mm f8 lenses were tested......
It is more likely the 90mm f8 SW Nikkor had higher contrast not "sharper" than the others. This combined with a very long list of possibilities plus cognitive bias, image rendition bias and LOTs more all figure into that assertion of "sharper".
As for Fujinon LF lenses being "Superior" again, the is completely subjective and dependent on the needs of image maker and print goals.
Higher contrast is not "sharper"... In many real world sheet film to print image making realities, the sharpest lens is NOT the best lens for a given print. It is a LOT more complex than optical performance of any given lens.
As for which wide 90mm for 4x5 or 5x7_13x18cm, what is the print's goal? As previous mentioned and many times before, there are NO ideal lenses for ALL print goals. Go directly back to the intent and goal of the finished print, then figure out what lens-camera-lighting-film-post processing is required to achieve that print.
Bernice
Quote:
Originally Posted by
Joseph Kashi
Lots of good suggestions in this thread. I'll through in my own qualitative comments, FWIW, based upon my actual testing of the following 90mm UWA lenses that I have for different sets of 4x5 and 5x7 gear, along with 75mm and 105mm Fujinon UWA lenses.
90mm/5.6 Fujinon SWD - very sharp, multi-coated, but really big (82mm filter size), heavy and suitable only for fairly static photography. It's an 8 element UWA with 105 degree coverage that works well with 5x7. However, the 90mm/f8 Nikkor does just as well up to 5x7 and in a significantly smaller package.
90mm/8 Nikkor - sharpest lens of the lot by a small margin and with a 67mm filter size. The 235mm/105 degree image circle/coverage is large enough for some movement on 5x7, and it's sufficiently small/light for backpacking My personal preference.
90mm wide angle Dagor - very, very small yet does a very nice job on 4x5. Downside - it's currently as expensive or more expensive than the Nikkor 90/8 on the used market and the shutter will probably require a CLA. Still, as a tiny 4x5 backpack lens, it's great. You can sort of eke out usable 5x7 coverage at very small apertures, but that's marginal.
90mm/6.8 Angulon I apparently have a good factory-coated later copy and it's decent at small apertures, but still seems softer and less contrasty than the similar 90mm Wide Angle Dagor. My least favorite.
Additional comparisons in nearby focal lengths:
75mm/8 Fujinon This is the first version of the SW series, with the inside lettering and single-coated. It's surprisingly sharp and small (58mm filters, I seem to recall). Some movement on 4x5 is possible as the image circle is about 180mm. It's Fujinon's equivalent to the original Super Angulon in terms of 6/4 design. This might be a good alternative to a 90mm UWA - you can always crop a bit or move in closer if you want a tighter composition.
105mm/8 Fujinon NSW This is a later UWA design using 6 air-spaced elements in six groups, multicoating, and lettering on lens barrel outside. It's extremely sharp and my preferred 5x7 UWA, but is overkill on 4x5 as it is a 77mm filter size lens.
The good performance of the later 105mm NSW Fujinon 6/6 design and the earlier 75mm/f8 6/4 design suggests that later NSW models of the Fujinon 90/8 would have similarly good 4x5 performance in a smaller, less expensive package. I did not get one because the 90/8 Fujinon does not cover 5x7.
Fujinon had a known commitment to good quality control for their LF lenses. Of the 11 Fujinon lenses that I purchased on the usedmarket, I have not had a single bad one. Qualitatively, I would generalize that one or two were average to somewhat above average while the rest were excellent or better.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Dan Fromm
Joseph, optical vignetting (the dread cos^4) afflects all lenses equally. There've been many discussions about when a center filter is necessary. To the extent that there's a consensus, it is that 90 mm is the shortest focal length that can be used on 4x5 without a CF.
When a 90 mm lens is shot straight ahead, i.e., with no movements, the very corners of the 4x5 frame will be 1.5 stops down from the center. Most photographers find this tolerable.
Benno, if this drop of is more than you can tolerate -- it will be if you shoot reversal film -- you should be aware that there are no center filters for the small thin inexpensive 90s you asked about. There are CFs for the modern wasp-waisted ones. To learn more, especially about CFs for lenses whose manufacturers never offered CFs, read my article on the French LF forum.
http://www.galerie-photo.com/center-...at-lenses.html
Woah that site has a wealth of information. Thank you! I always found CF really confusing but this is super helpful.
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Re: explain like I'm 5......... 90mm lenses
Quote:
Originally Posted by
Alan Klein
I just got an idea. I have an f/5.6 150mm. I'll turn the aperture down to f/8 while viewing and see how bright it is to help make a decision about my next lens.
Quote:
Originally Posted by
BennoLF
Wait but doesn't this not work? f/8 on a 90mm lens is a lesser transmittance than a a f/8 150mm, because the 150mm lens is a narrower FOV.
Both transmit the same
total amount of light but with a smaller angle the 150mm is brighter
per any given area. Or at least so the astro shooters tell me. Something about 'clear aperture size'
https://petapixel.com/2014/01/29/pic...y-photography/ look about 1/3 of the way down.
Am I talking crazy?
Yep, you're talkin' real crazy! :)
Think about it: if f/8 (or any other f-stop) was different from lens to lens, then you'd not get the same exposure for the same f-stop when you changed lenses.
The whole idea of f-stops is that is proportional to aperture size so the amount of light transmission is always the same for a given number.
Example: f/8 on a 90mm lens = 90 ÷ 8 = 11.25mm. f/8 on a 150mm lens = 150 ÷ 8 = 18.75mm. The longer lens has a larger aperture at f/8 than the shorter, which lets in more light, which compensates for the smaller field of view.
For a given aperture size for both lenses, your reasoning is correct. It's just that the f-numbers would then be different.
Example: A 9mm aperture on a 90mm lens = f/10 (90 ÷ 9 = 10). That same 9mm aperture on a 150mm lens = f/16.6 (150 ÷ 9 = 16.666...). The division works both ways.
Some things can affect transmission, like haze on lenses, reflections from lots of elements, etc., but that's a separate issue from the f-stop.
Best,
Doremus
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Re: explain like I'm 5......... 90mm lenses
I plan on shooting chromes down the road in addition to BW. Would that change anyone's opinions on which 90mm lens? (Note that I have all filters in 77mm. So I don't want to go above that filter size)
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Re: explain like I'm 5......... 90mm lenses
...color chromes and color negatives...
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Re: explain like I'm 5......... 90mm lenses
Pick a lens and go shoot! Don't get bogged down with paralysis by analysis!
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Re: explain like I'm 5......... 90mm lenses
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Originally Posted by
Alan Klein
I plan on shooting chromes down the road in addition to BW. Would that change anyone's opinions on which 90mm lens? (Note that I have all filters in 77mm. So I don't want to go above that filter size)
I'm currently only doing black and white ( 4x5 TMax 100 and 5x7 Delta 100) on LF and then scanning for digital post-processing and printing.
That hybrid process allows me a fair degree of digital correction in post-processing and I have a wide-format Epson 7900 printer that can do excellent BW prints if carefully calibrated. That affects my own approach.
Some of the best aspects of LF photography are that a wide range of options and approaches are open to everyone, that nearly any age, make and model lens can be adapted to a LF camera, and that DYI is feasible for virtually anyone with a modicum of experience. That makes LF quite flexible and allows everyone to find their own approach.
Chromes are certainly more susceptible to vignetting and more difficult to correct. I cannot comment about shooting LF chromes as I lack personal experience there.
That said, while some may take a different and possibly idiosyncratic view, IMHO sharpness and contrast are very important optical criteria, although certainly not the only ones, because higher sharpness and crisp contrast usually record the image more faithfully and thus provide more "information" and more accurate information, than lenses that are not as sharp nor exhibiting crisp contrast.
You'll of course find differing opinions - think 1930s Pictorialists vs. the f/64 revolution by Edward Weston, Ansel Adams, et al. It all depends upon what you want to do and whether you want to achieve a particular result and do so in-camera via a particular lens.
If you want a softer image, that's possible after the fact IF you start out with enough information in the original image capture, but you can't go the other way and try to extract more information from an image where the underlying information was never captured when the shutter was clicked.
Older lenses would likely be less suitable for chromes than more modern lenses from Nikon, Schneider, Rodenstock, and Fujinon, all of whose more recent products have excellent reputations.
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Re: explain like I'm 5......... 90mm lenses
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Originally Posted by
Dan Fromm
Joseph, optical vignetting (the dread cos^4) afflects all lenses equally. There've been many discussions about when a center filter is necessary. To the extent that there's a consensus, it is that 90 mm is the shortest focal length that can be used on 4x5 without a CF.
When a 90 mm lens is shot straight ahead, i.e., with no movements, the very corners of the 4x5 frame will be 1.5 stops down from the center. Most photographers find this tolerable.
Benno, if this drop of is more than you can tolerate -- it will be if you shoot reversal film -- you should be aware that there are no center filters for the small thin inexpensive 90s you asked about. There are CFs for the modern wasp-waisted ones. To learn more, especially about CFs for lenses whose manufacturers never offered CFs, read my article on the French LF forum.
http://www.galerie-photo.com/center-...at-lenses.html
Hi, Dan: Thanks for the information about the 1.5 stop vignetting - I forgot the formula. As I shoot only BW at this time on LF and then scan, post-process, and digitally print, I haven't been bothered by the vignetting due to my own style but I can certainly see how it would be a concern when shooting chromes as per the OP.
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Re: explain like I'm 5......... 90mm lenses
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Originally Posted by
Corran
Pick a lens and go shoot! Don't get bogged down with paralysis by analysis!
Yes!
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Re: explain like I'm 5......... 90mm lenses
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Originally Posted by
Bernice Loui
What were the "test" methods used to determine the SW Nikkor 90mm f8 was the "sharpest" of the lot?
*Camera used, film used, how was the film processed, subject & lighting conditions used, criteria used, how many representative sample(s) of SW Nikkor 90mm f8 lenses were tested......
It is more likely the 90mm f8 SW Nikkor had higher contrast not "sharper" than the others. This combined with a very long list of possibilities plus cognitive bias, image rendition bias and LOTs more all figure into that assertion of "sharper".
As for Fujinon LF lenses being "Superior" again, the is completely subjective and dependent on the needs of image maker and print goals.
Higher contrast is not "sharper"... In many real world sheet film to print image making realities, the sharpest lens is NOT the best lens for a given print. It is a LOT more complex than optical performance of any given lens.
As for which wide 90mm for 4x5 or 5x7_13x18cm, what is the print's goal? As previous mentioned and many times before, there are NO ideal lenses for ALL print goals. Go directly back to the intent and goal of the finished print, then figure out what lens-camera-lighting-film-post processing is required to achieve that print.
Bernice
Hello, Bernice:
FWIW, although I have mentioned that modern Fujinon lenses have proven to be reliably good for me and relatively more affordable used, I am not a Fujinon evangelist as I also use multiple modern lenses from Schneider, Nikkor, and Rodenstock. That said, the Fujinons and Rodenstocks have, for me, been the most consistently good optically.
I certainly understand your thoughts about the look of a certain lens as I also shoot regularly with eight classic lenses, four Zeiss Protar VIIa, a Voightlander 115mm Ultragon, and three Dagor lenses, and keep an appropriate one in every one of my large format kits from 4x5 through the 11x14 outfit. Some of these are as good as the better modern lenses and some less so.
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Re: explain like I'm 5......... 90mm lenses
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Originally Posted by
Doremus Scudder
Yep, you're talkin' real crazy! :)
Think about it: if f/8 (or any other f-stop) was different from lens to lens, then you'd not get the same exposure for the same f-stop when you changed lenses.
The whole idea of f-stops is that is proportional to aperture size so the amount of light transmission is always the same for a given number.
Example: f/8 on a 90mm lens = 90 ÷ 8 = 11.25mm. f/8 on a 150mm lens = 150 ÷ 8 = 18.75mm. The longer lens has a larger aperture at f/8 than the shorter, which lets in more light, which compensates for the smaller field of view.
For a given aperture size for both lenses, your reasoning is correct. It's just that the f-numbers would then be different.
Example: A 9mm aperture on a 90mm lens = f/10 (90 ÷ 9 = 10). That same 9mm aperture on a 150mm lens = f/16.6 (150 ÷ 9 = 16.666...). The division works both ways.
Some things can affect transmission, like haze on lenses, reflections from lots of elements, etc., but that's a separate issue from the f-stop.
Best,
Doremus
Wait now I'm further confused lol.
f/8 for any two different focal lengths is the same light input total. Isn't it kinda like slow, wide river or fast, narrow river?
A 3000000mm f/8 is picking up light from like .0005 degrees, so to get a balanced exposure it needs to pick up a HECK ton of light/degree.
A 30mm f/8 is picking up light from like a jillion degrees, so it's a much lower level of light/degree.
If you have a totally dark room with one lightbulb in it, metering a 'correct' exposure at f/8 will yield two different shutter speeds for two different focal lengths. Right?
The wider lens needs a longer shutter speed because it's viewing more darkness, so the lightbulb takes up a lower percentage of the exposure.
The tighter lens can have a faster shutter speed because it's just looking at a lightbulb.
This is all based on a metering system looking for an average of zone V.
I feel even crazier now but there's something in my mind that doesn't click.