Smudgy corners with 47mm Schneider SA f5.6 NON-XL

[rueyloon]

Hello

hi, I constructed my own camera with the 47mm Schneider SA f5.6 NON-XL with a horseman 6x9 film back.
I'm getting smudgy corners, is this lens side enough for 6x9 ? anyone with experience with this lens ?

I'm wondering if it is just the lens or the construction of my camera. The camera is 3D printed, and tolerance is around 0.5mm

Here is a scan
http://www.36frames.com/files/2016-03-01-0005.jpg

There is a 13mm shift down.

[rueyloon]

Here is another image with a single click.

http://www.36frames.com/files/000220010005.jpg

This one I probably shifted too much but you can see the corners are smudges, I just checked and the difference between the corners of the camera is 0.2mm which should be covered by the Aperture of F11 that I shoot at.

[Christoph B.]

Is the film perfectly flat?
Try shooting at daylight with a shorter exposure and try different aperture settings before you tackle nightshoots - this way you'll be able to narrow down your problems

By the way - what was your aperture setting for these photos?

I agree a picture of the camera would help. Are you using the lens in a shutter or did you make the whole system yourself and just screw in the elements? If so you may have gotten the distance between the elements wrong.

[rueyloon]

here are some images of the camera

[rueyloon]

[RomanN.]

For using film try to use aperture 16 or even 22 when you shift much. Also the lens could be not really good calibrated in the shutter- is this a really original shutter or did you just mounted the lens in this copal press shutter?

[RomanN.]

I forget something:
the corners are so soft, not only the image but also the film itself: the grain in the corners is soft.
it seems that you dont get the corners sharp with your scanner. some flatbed scanners like Epson 700/800 have poor plastic holders wher you dont get the film flat. Also Nikon 9000 with the standart holder can give so bad results.
check the film with a good loupe: 8x or 10x.
For that kind of photography anyway I would suggest you to use a drumscanner, even a cheap one. You get simply other quality than with CCD based scanners.

[rueyloon]

For using film try to use aperture 16 or even 22 when you shift much. Also the lens could be not really good calibrated in the shutter- is this a really original shutter or did you just mounted the lens in this copal press shutter?

no, I remounted it on the press shutter. Can't remember what was the original shutter, it comes with 3 shims on the back. Maybe I need try with removing the shims ? hmm...... more calibrations.....

[EricWHiss]

Well your camera seems pretty cool looking - nice job!  But I doubt the the lens is getting that soft so am betting something else is going on.   

[RomanN.]

no, I remounted it on the press shutter. Can't remember what was the original shutter, it comes with 3 shims on the back. Maybe I need try with removing the shims ? hmm...... more calibrations.....

Absolutely!
first of all:
remove all the shims- Schneider or rodenstock will never use shims on the back-never!
The shims will always be used on the front element.
You have a digital back - do you? that makes the calibration easier.
use live view fot it, make test pics then, when the results are not good than use the shims, first only one....
sometimes there is no need for shims, mostly one or two. tree will be anusuall.

[rueyloon]

Yes you are right I removed the shims and I can already see the difference on the GG. I still have to put at least one. If I remove all, the aperture can only close to about f5.6 to 8. If I put one I'll only lose f22. I think the back mounting pressed on the aperture without the shims.

Absolutely!
first of all:
remove all the shims- Schneider or rodenstock will never use shims on the back-never!
The shims will always be used on the front element.
sometimes there is no need for shims, mostly one or two. tree will be anusuall.