Schneider 90mm f/8 Super Angulon - lens quality at F16?

[Jimaimed]

Hi everyone,

I'm new to LF photography and I got a question about the quality of my lens
I noticed all my negatives are sharp when F45 is applied, below you can find an image of the building across the street at F45 (1/4sec)
Last weekend I got out and shot with the same lens at F16 (1/60) a wall from close distance (2m or 5-6 foot), except for the hole in the middle everything else in the image is bad, vignette and unsharpness although all my movements
are zero leveled except for a very slight rise/fall of the filmplane and some very little shift to get the hole in the middle of the picture.

I never tested the lens at F45 at close distance like this metal wall but I'm suprised even at F16 for a wide angle with this kind of results.

any tips or help what might have gone wrong or somethings wrong with the lens, blades, shutter or could it be only bad camera movements?

shot with Sinar F2 - 4x5 (HP5+ digital scan)

thanks in advance

[IanG]

With no movements used there shouldn't be any vignetting with that lens it has plenty of coverage, optimum sharpness should be at f22 but f16 should be OK.

You need to get the lens checked, maybe post a picture of it here. There's something not right, it wouldn't be the first time that a lens has been sold with the wrong rear elements or is missing spacers etc. Check the dimensions they are listed here.

welcome to the Forum BTW

Ian

[Jimaimed]

Hello Ian,

thanks for the reply.
I took some pictures with my iphone, you've put them on flickr in an album, mounted and unmounted to the lensboard.
The lensboard has a retaining ring to fit the copal, that was made by SK Grimes.
Dunno if this helps?
https://www.flickr.com/photos/jimhav...57660979944716

Thanks in advance

Best,
Jim

[ImSoNegative]

it actually looks like a bit of swing was applied

[IanG]

That's an odd one Jim, the serial number on the rear cell matches so is correct. The one thing that might be an issue which is hard to tell from the photos is whether the rear cell is correctly spaced - fully screwed into the shutter, coverage and sharpness will drop off if it's not. My guess looking at the pictures is it's not fully screwed in and the rear call is fouling on the adapter, I'm assuming it's the early Compur #00 version.

As the 90mm f8 Super Angulon covers 7x5 there's no way you would get vignetting on 5x4 without quite significant movements or quite significant incorrect spacing.

Ian

[Bob Salomon]

To me that building is not all that sharp. Your lens is diffraction limited at f22 on 45. Beyond that you will lose performance, especially in the center. Optimal exposures will be at f22. Reshoot that building at f22 and then see what happens. Your lens is also optimized for about 1:20 and is not very good for macro. So first see how it performs at optimal aperture and within it's optimal performance range. If, at f22, the results are the same as the building shot then the lens should be sent to a competent service center, with an optical bench, to see what is wrong with it.

[Jimaimed]

hey guys,

while assembling the lens again to the lensboard I noticed some spacing like Ian mentions above, it looks well fit together now!!
This might have been the problem, I'll shoot these images again soon and get back to you.
For close up shots, what lens would you suggest? I also have the Rodenstock 210mm/5,6 but never used it for close up architectural photography.
thanks again, much appreciated!

Best,
Jim

[Bob Salomon]

hey guys,

while assembling the lens again to the lensboard I noticed some spacing like Ian mentions above, it looks well fit together now!!
This might have been the problem, I'll shoot these images again soon and get back to you.
For close up shots, what lens would you suggest? I also have the Rodenstock 210mm/5,6 but never used it for close up architectural photography.
thanks again, much appreciated!

Best,
Jim

Best for that type of shot would be a lens corrected for 1:5, or, at worst, 1:10. Read lens specs. If you want closer then a macro lens. Weather a 210 will work will depend on your camera's bellows extension.

[IanG]

hey guys,

while assembling the lens again to the lensboard I noticed some spacing like Ian mentions above, it looks well fit together now!!
This might have been the problem, I'll shoot these images again soon and get back to you.
For close up shots, what lens would you suggest? I also have the Rodenstock 210mm/5,6 but never used it for close up architectural photography.
thanks again, much appreciated!

Best,
Jim

If you were shooting with the lens mounted as in the first 2 photo's then the spacing was almost certainly wrong, the converter from #00 to #0 needs to be fully screwed onto the rear of the shutter. If you have a vernier you could check the overall length of the lens off the lens board and make sure it's the same when fitted. The tolerances with WA LF lenses are quite fine and often shims are used to optimise performance. Good luck with your tests.

The 210 Sironar should be fine for close up architectural photography, you don't need a Macro lens for that, just remember to take into account the additional bellows extension and correct the exposure.

Ian