View Full Version : Schneider Super-Angulon 75mm and Vignetting on 4x5?
Hello,
I want to ask a question to see if anyone might have answers or thoughts. I have a Schnieder 75mm 1:8 Super-Angulon, which is exhibiting very strong vignetting on 4x5 film. It's most definitely a lenss made for 4x5, everything on Schneider's website makes that clear. I am using an Intrepid 4x5 camera and a recessed board to be able to focus correctly (because the camera doesnt like 75mm without having a recessed lens board). I know that the image is in focus; film tests prove that. And I know that there are no visible movements; no swing, no rise, nothing that can be detected by visual checks. But the vignetting on this lens is so strong, with about half of the image frame covered by vignetting, and the corners in pure black.
I am curious why would a lens that is clearly designed for 4x5 give such vignetting on that format? What am I missing? Is this something wrong with the Intrepid camera itself that I am missing? I am confussed, disheartened, and obviously saddened that I might have to just write off this lens as worthless....
ic-racer
6-Oct-2022, 22:12
Can you show a picture of the negative?
ic-racer
6-Oct-2022, 22:14
So, when you peek in the corners of the GG the pupil area or lens opening is totally obscured?
231565
Richard Wasserman
6-Oct-2022, 22:35
I used a 75mm Super Angulon on a Cambowide for many years and never had the kind of vignetting you are describing. The lens does vignette, but not nearly so dramatically. Is it possible that the camera bellows are blocking the image? I am not familiar with the Intrepid camera, but very wide-angle lenses, such as a 75mm, usually need a bag bellows designed for that use. Like this one made for Sinar cameras— https://www.bhphotovideo.com/c/product/802571518-USE/sinar_233007_4x5_wide_angle_bellows.html
Steve Goldstein
7-Oct-2022, 01:23
What f-stop is the lens set to?
Tobias Key
7-Oct-2022, 01:25
I have just been working on this image I shot with my 75mm Super Angulon 5.6 hopefully this is a useful reference. This was shot with about 10mm of rise so any vignetting would be more obvious at the top of the frame. There is some but it is subtle. Conditions and subject will obviously make a difference, as would film choice.
https://live.staticflickr.com/65535/52408643842_4a18dc195a_b.jpg (https://flic.kr/p/2nRaZVC)St Michael's Up Marden (https://flic.kr/p/2nRaZVC) by Toby Key (https://www.flickr.com/photos/tobykey/), on Flickr
I once purchased a wide angle FUJINON lens that should have easily covered the 4x5 format but it didn't. Turned out that the front and rear sets of optics were mismatched.
I once purchased a wide angle FUJINON lens that should have easily covered the 4x5 format but it didn't. Turned out that the front and rear sets of optics were mismatched.
This is a good point. Maybe you are not using what you think you are using.
In addition, are there any filters on the lens? Are you using a lens shade?
Are you sure the lens is in the middle of the film plane?
Pictures of the lens would help.
Daniel Unkefer
7-Oct-2022, 10:48
https://live.staticflickr.com/65535/49078896253_8833033949_b.jpg (https://flic.kr/p/2hLWaYr)First 5x7 Norma Test 75f8 SA CF E3 150F9 Aristo2 Perfection 3.5min (https://flic.kr/p/2hLWaYr) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr
My one and only (so far!) test of my 5x7" Sinar Norma. Also testing the Schneider 75mm F8 Super Angulon. I have the matching Schneider center filter marked "Filter for 75mm F8 SA". 5x7 HP5 D76 Omega E3 with Omegalite Head, Arista Ultra #2 RC paper Perfection D developer 3.5 minutes
I wanted to see the coverage and sharpness at the edges of the field with this lens without the center filter. It passed the test.
Bob Salomon
7-Oct-2022, 12:32
https://live.staticflickr.com/65535/49078896253_8833033949_b.jpg (https://flic.kr/p/2hLWaYr)First 5x7 Norma Test 75f8 SA CF E3 150F9 Aristo2 Perfection 3.5min (https://flic.kr/p/2hLWaYr) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr
My one and only (so far!) test of my 5x7" Sinar Norma. Also testing the Schneider 75mm F8 Super Angulon. I have the matching Schneider center filter marked "Filter for 75mm F8 SA". 5x7 HP5 D76 Omega E3 with Omegalite Head, Arista Ultra #2 RC paper Perfection D developer 3.5 minutes
I wanted to see the coverage and sharpness at the edges of the field with this lens without the center filter. It passed the test.
The filter does not change the vignetting it reduces the fall off.
That's not centered. If it were, it would cover.
Daniel Unkefer
7-Oct-2022, 16:27
It's 5x7 film. So no it won't. Image circle of the 75mm F8 is 181mm according to my Burleigh Brooks catalog, which is only 1mm more than the nominal 7" long dimension of the film. There is a nice 4x5 size section in the center (choose your cropping) that is sharp enough for my needs. Changing the subject, just a quess OP but I think your Intrepid bellows or interior camera "throat" may be vignetting your image circle. Check the corners, through the groundglass cutouts, to see if the lens is covering and perhaps the problem will reveal itself. Perhaps a deeper recessed board would help.
The OP was about 4x5 film. I don't understand at all why you are talking about 5x7 film. How does this relate to the OP?
So first, thanks for the replies.
Also, that image of the church from Toby is really amazing. I see the vignetting on the top, but that is a stunning photography. Great work.
I ran some more tests yesterday, and think I may have sorted out what is happening, based on my film development. I was using a polarising filter during my initial shots (I wanted to cut reflections on the water), and taking that off did seem to make a noticeable difference. But the real issue seems to be with centering the rise on the Intrepid 4x5 camera. I've been doing this by eye, but clearly, that is not enough. What is troublesome is that the Intrepid doesn't really have a means of knowing zero rise, or it doesn't until I mark my front standard with something very permanent so that I will know instantaneously in the future. Worse, even with a (cheap) fresnel, viewing the corners on the ground glass is impossible; it's pitch black. Which suggests I need to invest in something (a better fresnel, perhaps, and/or a better ground glass).
Yesterday, I used a laser level and measuring tape to find true zero rise on the front and rear standards, and then took out my trusty Leatherman to carve a mark on each standard. Then I tried again with the 75mm (set to f/32 to answer the question above), an re-took the photograph (once with the Polariser, once without). I now see that the lens does indeed cover 4x5, which is an enormous relief, as well as focus to infinity (normally this won't happen on an Intrepid unless one uses some kind of recessed lens board).
This doesn't completely solve my problems, but it does save me from binning the lens. I am not sure how I am going to compose shots if I cannot see the corners..... But, that is a different problem......
maltfalc
8-Oct-2022, 20:22
Worse, even with a (cheap) fresnel, viewing the corners on the ground glass is impossible; it's pitch black. Which suggests I need to invest in something (a better fresnel, perhaps, and/or a better ground glass).
with a short focal length lens you also need a short focal length fresnel.
ic-racer
9-Oct-2022, 07:46
Dark corners on film are the result of two independent processes. One is a decrease in light energy on the film as the light's angle of attack on the film changes from 90 degrees, so called 'cosine falloff.'
The other is a mechanical process whereby the pupil appears smaller at the edges of the field. Analogous to shutter efficiency increasing with small apertures, the same can be said for this mechanical vignetting. Small apertures increase the efficiency of projection, decreasing the effects as the angle of view extends to the absolute cutoff of light. See image in above post #3.
Dan Fromm
9-Oct-2022, 08:21
Dark corners on film are the result of two independent processes. One is a decrease in light energy on the film as the light's angle of attack on the film changes from 90 degrees, so called 'cosine falloff.'
The other is a mechanical process whereby the pupil appears smaller at the edges of the field. Analogous to shutter efficiency increasing with small apertures, the same can be said for this mechanical vignetting. Small apertures increase the efficiency of projection, decreasing the effects as the angle of view extends to the absolute cutoff of light. See image in above post #3.
ic, for the life of me I can't understand your explanation of mechanical vignetting. As I understand it and see it when I play around with w/a lenses, stopping down reduces the exit pupil's diameter, increases the angle at which rays coming from the exit pupil's edge are obstructed by the rear barrel. This may be what you meant to say.
Bernice Loui
9-Oct-2022, 11:42
Issue here is the camera coupled with the image maker's lack of understanding and experince using a view camera.. Victim being the 75mm f5.6 Super Angulon. Know the Schneider 75mm f5.6 Super Angulon has been in production for decades burned umpteen sheets of film by a vast number of sheet film view camera users world wide for decades.. There are extremely good and valid reasons why the 75mm f5.6 Super Angulon has endured this test of time and image making by so many image makers world wide..
75mm f5.6 Super Angulon has a spec image circle of 198mm at f22, image circle needed for 4x5 is 154mm. This gives an image circle margin of 44mm or plus/minus 22mm at f22.
~Hint, avoid using f32 or smaller than absolutely needed exposure apertures as there is a lens performace trade off here. If f16 produces enought percieved in focus areas in the image good enough, using a smaller expsoure aperure is not going to "make it better"...
Issues with the Intrepid 4x5 camera has much to do with no camera center indcators or click stops to allow the user to positively determine and know the front standard is centered to the rear standard with no rise/fall/shift or tilt/swing. This is not a small issues, this is IMO a very serious user limitation. To cure this will be on-going problem, add these indicators or stops on your own to stop this problem once and for all.
The inability to focus at infinity with the camera standards not centered is due to the bellows being compressed and restricting the amount of bellows compression needed to achieve lens focus at infinity. This also means limitied camera movements with this focal lenght of lens.. The solution is to use a bag bellows if possible. Another camera limitation that does not properly support the lens being used.
~Another example of how lens should decide camera choice and camera's capabilities to properly support the lens to be used.
As for the Fresnel ground glass image "brighter" stop using any Fresnel lens on the ground glass as a "viewing aid". They will cause more problems with wide angle lenses on view cameras than any possible image viewing assistance. The far better overall solution is to use the very best ground glass available, a good dark cloth, a tilting ground glass loupe and learning how to view the ground glass image with NO fresnel lens.
75mm is not that wide on 4x5, what would be wide is 47mm. In this case the ground glass image at the edges will be more difficult to view than the 75mm due to the angle of light rays to the ground glass and inherient light fall off (vignetting) of "Biogon" style wide angle large format lenses.
It should be noted these "biogon" style wide angle lenses do not behave in the same way as Retrofocus wide angle lenses commonly found in fixed to the camera body cameras.. These Retrofocus wide angle design lenses have an advantage to correct for light fall off (vignetting) due to the fixed distance between film or digital imager distance to the rear of the lens. When this distance is longer than the effective lens focal lenght (14mm lens with a fixed back focus of say 40mm) the rays of light exiting the lens rear is forced into being a smaller cone of light that can aid in reducing light fall off or vignetting.. Or why the habits or what has been learned from using fixed to the box cameras do not apply to this view camera wide angle lens stuff.
Correction for light fall off (vignetting) of Biogon style wide angle view camera lenses is done using graduated netrual density center filters that are effectively the reverse of the inherient light fall off designed into the LF wide angle lens.. another topic.
How much light fall off or vignetting is acceptable in the image is decided by the image maker, type of film beiing used and ...
Bernice
But the real issue seems to be with centering the rise on the Intrepid 4x5 camera. I've been doing this by eye, but clearly, that is not enough. What is troublesome is that the Intrepid doesn't really have a means of knowing zero rise, or it doesn't until I mark my front standard with something very permanent so that I will know instantaneously in the future. Worse, even with a (cheap) fresnel, viewing the corners on the ground glass is impossible; it's pitch black. Which suggests I need to invest in something (a better fresnel, perhaps, and/or a better ground glass).
Yesterday, I used a laser level and measuring tape to find true zero rise on the front and rear standards, and then took out my trusty Leatherman to carve a mark on each standard. Then I tried again with the 75mm (set to f/32 to answer the question above), an re-took the photograph (once with the Polariser, once without). I now see that the lens does indeed cover 4x5, which is an enormous relief, as well as focus to infinity (normally this won't happen on an Intrepid unless one uses some kind of recessed lens board).
This doesn't completely solve my problems, but it does save me from binning the lens. I am not sure how I am going to compose shots if I cannot see the corners..... But, that is a different problem......
Robert Opheim
9-Oct-2022, 13:46
I have always cut the corners of my ground glass to check to see if there is a full circular iris when stopped down. Depending if you are using a bag bellows - with one there can be more movement then the lens has image circle. Sometimes a non-wide angle filter can cut off some image circle at the edge. As far as your Intrepid camera - you may need to add a mark to show the center location.
Maris Rusis
9-Oct-2022, 17:23
Checking wide angle lens coverage by trying to see the back of the lens through the clipped corners of a ground glass is downright difficult. You can end up in some awkward contortions and the tiny exit pupil of the lens is easy to miss.
But there is an easier way. Go around to the front of the camera and look through the lens. If you can see all four corners of the 4x5 frame through the entrance pupil of the lens then those corners can also see you and there will be no vignetting.
Tobias Key
10-Oct-2022, 01:27
When I use my 75mm I find it helps to look at the ground glass at an angle when you are checking the corners. Line you eyes up with where the light is coming from if that makes sense. I piece the image together by moving my head around, which was awkward at first but you do get used to it.
How many photographers are going to change their fresnel -- back & forth -- because they switched from a 250mm to a 75mm?
I'm sure there are some, but not me!
Bernice Loui
10-Oct-2022, 12:20
Easier and simple to leave off the Fresnel, done.
Bernice
How many photographers are going to change their fresnel -- back & forth -- because they switched from a 250mm to a 75mm?
I'm sure there are some, but not me!
Bernice Loui
10-Oct-2022, 12:22
Essentially the same as using a tilting ground glass loupe or a hand held loupe tilted in the same way, from edge to center of the GG/lens.
Bernice
When I use my 75mm I find it helps to look at the ground glass at an angle when you are checking the corners. Line you eyes up with where the light is coming from if that makes sense. I piece the image together by moving my head around, which was awkward at first but you do get used to it.
How many photographers are going to change their fresnel -- back & forth -- because they switched from a 250mm to a 75mm?
I'm sure there are some, but not me!
Depends on the camera... When I was using a 4x5 Sinar X with its reflex back in the field, I could change the fresnel (in its "clip-on" frame) in about 5 seconds. With the 8x10 Norma, changing the fresnel involved removing 4 small screws from 2 small brackets which held in the GG and the fresnel lens in place - I would have been crazy to do that in the field, and was too much trouble to do even in the studio.
Lachlan 717
10-Oct-2022, 21:55
I ran some more tests yesterday, and think I may have sorted out what is happening…. the real issue seems to be with centering the rise on the Intrepid 4x5 camera. I've been doing this by eye, but clearly, that is not enough. What is troublesome is that the Intrepid doesn't really have a means of knowing zero rise, or it doesn't until I mark my front standard with something very permanent so that I will know instantaneously in the future. Worse, even with a (cheap) fresnel, viewing the corners on the ground glass is impossible; it's pitch black. Which suggests I need to invest in something (a better fresnel, perhaps, and/or a better ground glass).
Yesterday, I used a laser level and measuring tape to find true zero rise on the front and rear standards, and then took out my trusty Leatherman to carve a mark on each standard.
The latest 8x10” (a.k.a. the MkIII) has centering marks on the front standard, albeit small and pretty much useless…
I’ll be (re)marking these to make it more obvious when it’s centred.
231690
One thing to keep in mind is that while some (most?) cameras have a centering mark for the front standard, lens centering also depends on the lensboard. Some cameras -- like mine -- are designed for off-centered lensboards. Even if your front standard is centered, if the wrong lensboard is used, the lens will still not be centered. Sometimes it can be difficult to know if your camera is designed for centered lensboards or off-centered lensboards -- and if so, by how much.
I have a 37mm lens that is too large to fit on an off-centered lensboard, but it fits on a lensboard with a centered hole. When I use it, I have to manually adjust the front standard to get the lens in the middle of the film/ground glass.
Daniel Unkefer
11-Oct-2022, 09:23
https://live.staticflickr.com/65535/52420108097_d1c5c48844_b.jpg (https://flic.kr/p/2nSbKRc)SONY DSC (https://flic.kr/p/2nSbKRc) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr
Three Ocular Magnifiers that I own, Plaubel Peco Profia, and Sinar Norma. My preferred way of viewing the glass, especially with the 75mm F8 barrel Norma SA and the 75mm F5.6 Norma barrel SA. The 75mm F8 is not bright to look through, I use fresnels on all my cameras. With the Monocular Oculars, you hve to get used to moving your head around quite a bit, I have found that I can view the subject (especially the corners), in quadrants of bright viewing. It does take some getting used to, but it works for me and I'm getting sharp results. And I can see the screen properly, just not all at once.
This idea can be incorporated into other types of view cameras.
Bernice Loui
11-Oct-2022, 11:29
Brings up a view camera curiosity...
~Why do the majority of field folder / sheet film press cameras lack centering detents and measurement scales with a reference zero?
Nearly every field folder from Wood to metal lack these basic yet IMO, extremely importaint features...
How difficult could adding these reference zero marks and scales be?
~Why do the majority of modern monorail view cameras have centering detents and measurement scales with a reference zero?
Nearly every modern monorail view camera used to date has detents and reference zero.
Personally, any camera without reference zero scales/marks or some means of positive zero refernce position of the front/rear standards is totally unacceptable. Details like this make the specific view camera that much more difficult to use. In the case of those that apply camera movemens for nearly every image made or if combined camera movements on the front and rear standards from tiny to significant, the lack of centering detents, zero referenced scales and similar makes applying camera movements an extra effort. Scales on the camera can also be used as an indicator as to how much lens image circle has been used up and how much lens image circle remains available.. Losing an image/sheet of film to applying more camera movement than the lens image circle can provide is no fun at all..
Bernice
The latest 8x10” (a.k.a. the MkIII) has centering marks on the front standard, albeit small and pretty much useless…
I’ll be (re)marking these to make it more obvious when it’s centred.
231690
Brings up a view camera curiosity...
~Why do the majority of field folder / sheet film press cameras lack centering detents and measurement scales with a reference zero?
Nearly every field folder from Wood to metal lack these basic yet IMO, extremely importaint features...
How difficult could adding these reference zero marks and scales be?
Bernice
Makes no sense to me. Luckily mine have the mark, but neither the manufacturer, nor the distributor, nor the seller, nor the instructions, indicated that off-set lens boards were needed.
Bernice Loui
11-Oct-2022, 12:00
Why field folder view cameras lack center marks or zero refernced scale is a question worthy of discussion..
The off center lens board ala Technika goes back the the design of the Linhof Technika which the basic design was carried over by other field folder brands making similar field folder cameras.
If the field folder has been designed for a off center lens board and a centered lens board is used, lens image circle is used up due to the de-centering of the lens mounting.. not good.
Oh, if a recessed lens board is combined with the offset lens mounting hole.. this can become "interesting" in various ways..
BTW, the Linhof Technikardan uses centered Technika style lens boards..
Bernice
Makes no sense to me. Luckily mine have the mark, but neither the manufacturer, nor the distributor, nor the seller, nor the instructions, indicated that off-set lens boards were needed.
Why field folder view cameras lack center marks or zero refernced scale is a question worthy of discussion..
Oh, if a recessed lens board is combined with the offset lens mounting hole.. this can become "interesting" in various ways..
Bernice
I've seen plenty of field cameras that have a centering mark -- including my two TOKOs. They made four models, and they all have the mark. But I've seen it on other field cameras as well -- so it's obviously a decision that the manufacturer makes. Why so many would leave it off? Got me!
My recessed Linhof/Wista board is off-set -- so it works for me. If it were not off-set, not only would I have to change the height of the front standard, but more importantly, if it were in the center of the recess there would be no room for the shutter controls.
Alan Klein
12-Oct-2022, 06:50
Why field folder view cameras lack center marks or zero refernced scale is a question worthy of discussion..
The off center lens board ala Technika goes back the the design of the Linhof Technika which the basic design was carried over by other field folder brands making similar field folder cameras.
If the field folder has been designed for a off center lens board and a centered lens board is used, lens image circle is used up due to the de-centering of the lens mounting.. not good.
Oh, if a recessed lens board is combined with the offset lens mounting hole.. this can become "interesting" in various ways..
BTW, the Linhof Technikardan uses centered Technika style lens boards..
Bernice
My Chamonix 45H-1 field camera has center marks to set the standard but no detents. You have to look to line them up. There are detents but only for setting the standards to the vertical position.
Shoultn't photographers who have cameras without marks be able to calculate where the centers are and then hand mark those places with a marker of some sort?
Shoultn't photographers who have cameras without marks be able to calculate where the centers are and then hand mark those places with a marker of some sort?
Easier said than done -- and some people don't even know they should do it -- let alone what type of lens board they should be using.
Bernice Loui
12-Oct-2022, 11:44
Fave 8x10 field folder, Toyo 810M has refernce marks, Fave 4x5/5x7 field folder Canham DLC has refernce marks.. Linhof Technika, the front standard simply pulls out once the focus rails have been moved back to meet the focus rails inside the body... These are very viable solutions to a very basic view camera need. Focus distace scales are very often still lacking.. Focus scales are very useful in many ways.. as previously discussed.
https://www.largeformatphotography.info/forum/showthread.php?168934-Technique-for-increasing-depth-of-field/page4
IMO, not a lot needed for the camera brand to add marks/scales and a bit more to add detents.
The Sinar Norma has marks and detents and scales where they are essential, Linhof Technikardan has a zero/reference position for both front/rear standards in their static position with detents (on S version), markes and scales where essential and needed.
Speculation, field folders do not have the same camera movement expectations/requirements as a monorail view camera. Add to this, the visual esthetic aspects of a field folder -vs- monorail view camera.. and user expectations/requirements.
Bernice
My Chamonix 45H-1 field camera has center marks to set the standard but no detents. You have to look to line them up. There are detents but only for setting the standards to the vertical position.
Shoultn't photographers who have cameras without marks be able to calculate where the centers are and then hand mark those places with a marker of some sort?
Lachlan 717
12-Oct-2022, 12:51
Filing a detent on the front standard of an Intrepid with a rat-tail file will be easy. Doesn’t need to be too deep; just a slight notch would suffice.
A simple correspondence scratch mark on same standard would be even easier. Occam’s Razor springs to mind…
Filing a detent on the front standard of an Intrepid with a rat-tail file will be easy. …
The hard part is knowing where to put it.
Bernice Loui
12-Oct-2022, 15:30
Going to be critical of the folks at Intrepid camera and others that do not put zero refernce lines, stops, detents and such.. How difficut could this be... Honestly... to add such an importaint basic feature of any view camera..
Dinky detents or illegable marks or similar... not gonna work, These needs to be BIG_BOLD and user friendly, there are about zero excuses for this other than economizing, inconsiderate to users needs or a belief it's users/owners do not value this very basic feature. Or, it's user/owner base lack the awareness of how importaint these refernce zero detents, marks or similar are..
Previously, there was the Oooops of not opaque enough Intrepid lens boards made of FR4 that caused film fogging..
https://www.largeformatphotography.info/forum/showthread.php?160403-Disastrous-Consequences-(solved-fog-with-Intrepid-lensboard)
Bernice
The hard part is knowing where to put it.
I'm going to agree with this and other remarks Bernice has made in this thread..... My lack of foresight made me think that I could sort of wing it with centering the lens; but that wasn't the case, and my first set of tests (which led to this original post) definitely misled me into thinking there was something up with the 75mm lens itself.
It took careful measurement before I could get a centering mark correctly made and then I could look through the front of the lens as someone suggested above and really see I had it right and center. For the post above about how to do so, it really was a bit fiddly. I have a centered lens board, so at least I didn't need to worry about off-center and all that. Then I took the camera, made sure both the standards were dead level (fortunately the Intrepid does have little bubble levels for this), and focussed on infinity, easy enough. I moved the rise until it looked centered, but then used a protracter to measure the angle of the bellows (the Intrepid has a standard, not a bag bellows) as they depart from the front standard. There are two angles to measure -- the top of the bellows and the bottom. I then adjusted rise so that the angle on top and the angle on the bottom were identical. I have a digital angle finder so this made things easier. I measured the angles at the rear standard too to make sure i was getting a right triangle on both top and bottom. Then , I made my mark exactly where the metal screw peeks through. I might be a millimeter off, but after taking photographs (of a flat stone wall that was pretty flatly lit), and then checking the negatives, it is right.
It wouldve been easier had Intrepid put zero marks on the camera to begin with, but I have learned something.
Thanks for the tips on tilting my loupe. I am working on that. I will say, I prefer the image on the gg after taking the fresnel out. Whether that is personal preference or whatever, I leave for others to discuss.
panj
Going to be critical of the folks at Intrepid camera and others that do not put zero refernce lines, stops, detents and such.. How difficut could this be... Honestly... to add such an importaint basic feature of any view camera..
Dinky detents or illegable marks or similar... not gonna work, These needs to be BIG_BOLD and user friendly, there are about zero excuses for this other than economizing, inconsiderate to users needs or a belief it's users/owners do not value this very basic feature. Or, it's user/owner base lack the awareness of how importaint these refernce zero detents, marks or similar are..
Previously, there was the Oooops of not opaque enough Intrepid lens boards made of FR4 that caused film fogging..
https://www.largeformatphotography.info/forum/showthread.php?160403-Disastrous-Consequences-(solved-fog-with-Intrepid-lensboard)
Bernice
Bob Salomon
12-Oct-2022, 16:38
I'm going to agree with this and other remarks Bernice has made in this thread..... My lack of foresight made me think that I could sort of wing it with centering the lens; but that wasn't the case, and my first set of tests (which led to this original post) definitely misled me into thinking there was something up with the 75mm lens itself.
It took careful measurement before I could get a centering mark correctly made and then I could look through the front of the lens as someone suggested above and really see I had it right and center. For the post above about how to do so, it really was a bit fiddly. I have a centered lens board, so at least I didn't need to worry about off-center and all that. Then I took the camera, made sure both the standards were dead level (fortunately the Intrepid does have little bubble levels for this), and focussed on infinity, easy enough. I moved the rise until it looked centered, but then used a protracter to measure the angle of the bellows (the Intrepid has a standard, not a bag bellows) as they depart from the front standard. There are two angles to measure -- the top of the bellows and the bottom. I then adjusted rise so that the angle on top and the angle on the bottom were identical. I have a digital angle finder so this made things easier. I measured the angles at the rear standard too to make sure i was getting a right triangle on both top and bottom. Then , I made my mark exactly where the metal screw peeks through. I might be a millimeter off, but after taking photographs (of a flat stone wall that was pretty flatly lit), and then checking the negatives, it is right.
It wouldve been easier had Intrepid put zero marks on the camera to begin with, but I have learned something.
Thanks for the tips on tilting my loupe. I am working on that. I will say, I prefer the image on the gg after taking the fresnel out. Whether that is personal preference or whatever, I leave for others to discuss.
panj
If you rely on seperate levels on the front and back you can also be sure that they will not agree with each other. Get a good level that you can use on both standards.
Lachlan 717
12-Oct-2022, 19:53
Going to be critical of the folks at Intrepid camera and others that do not put zero refernce lines, stops, detents and such.. How difficut could this be... Honestly... to add such an importaint basic feature of any view camera..
Dinky detents or illegable marks or similar... not gonna work, These needs to be BIG_BOLD and user friendly, there are about zero excuses for this other than economizing, inconsiderate to users needs or a belief it's users/owners do not value this very basic feature. Or, it's user/owner base lack the awareness of how importaint these refernce zero detents, marks or similar are..
Bernice
Whilst I agree in principle, nobody should assume that these are much more than a gateway drug.
Intrepid’s business plan is to provide an entry level camera at an EXTREMELY good price. You know this (or you should) before you enter their ecosystem.
If this is true, I would argue that their target market isn’t those using semi-exotic lenses such as ultrawides.
Yes, we can argue “should haves”; however, they can more convincingly argue “we manage our business for the rule, not the exception”.
If it having detents keeps the price down for the 95% who don’t need them, it makes sense not to add them.
One final point - I recently received an 8x10 MkIII (the new one). The screws that hold the GG clips in place were both loose on arrival and wouldn’t tighten (either hole’s too big and/or stripped thread). So, I contacted Intrepid about this as well as passing on a couple of thoughts on the design that might be improvements. Intrepid quickly responded, saying they really welcome this kind of feedback and pass it on to their designers for consideration. This didn’t seem plecation; if felt that they generally do. So, we might see detents added one day!
While a centering detent would be best, my field cameras just have simple red dots for visual alignment of the front standard. That must have set the manufacturer back about two cents. Intrepid and other economy cameras have no excuse.
And centering is not only important for wide-angle lenses. If someone buys an Intrepid to save money, they will also be buying economy lenses -- which make centering even more important.
Tin Can
13-Oct-2022, 07:28
I consider my all metal cameras to be top quality and LN
however detents are not always perfect and can be frustrating
not going to malign any dead tech or new
Alan Klein
13-Oct-2022, 10:39
If you rely on seperate levels on the front and back you can also be sure that they will not agree with each other. Get a good level that you can use on both standards.
I use this level.
https://www.bhphotovideo.com/c/product/780406-REG/Vello_BL_HS3_Three_Axis_Hot_Shoe_Bubble_Level.html
Lachlan 717
13-Oct-2022, 12:01
While a centering detent would be best, my field cameras just have simple red dots for visual alignment of the front standard. That must have set the manufacturer back about two cents. Intrepid and other economy cameras have no excuse.
And centering is not only important for wide-angle lenses. If someone buys an Intrepid to save money, they will also be buying economy lenses -- which make centering even more important.
My Intrepid does have centering marks (see above photo). They’re just not very well defined.
As for cheap lenses, not too many cheap sub-90mm (and their associated small ICs) lenses out there last time I looked… Plenty of cheap 90mm, 150mm and 210mm, though.
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