Zeiss Ikon 515/16 - how sharp it should be?

[kansalliskala]

It is pre-war folder, not even very prestigious, pretty cheap, with Novar Anastigmat 7,5 cm / 4.5.

About 6 mpix "scan" of Kodak 100 slide.



Comparing it to Yashicaflex C with, Yashikor (Tomioka) triplet 80/3.5 on Fuji 100 slide.



100% crops

Novar
you can still see the spokes of the bicycle wheel.



Yashikor
of course it is better, it is 15 years newer

[PaulC]

If it is well-adjusted, it can be very, very sharp indeed. It looks to me as if your main point of focus was well in front of the bike wheels. I think if you are really careful in the way you use this you will probably get even better results than you have so far.

This is a very tight crop from a Nettar 516 (the 6x4.5 version) with the same basic Novar f4.5 lens. The file was scanned and sized to 21MP, the same as a 5D Mk2, and this is a 100% crop taken right from the middle of it:



As you can see, even the keyhole in the Yale lock is visible.

This is the original it was cropped from:

[kansalliskala]

The film grain is what you see next on that scan.

[PaulC]

So, you agree that the Novar is, potentially, a sharp lens

[kansalliskala]

There is also some sort of film flatness problem, the right and left borders of the picture are "fuzzy" but top and bottom are clear. Don't know if it is film transport or pressure plate that causes it. If it is pressure plate it could explain some out of focus problems. All infinity shots are not very sharp.

[PaulC]

I always follow a very strict proceedure when taking a picture with any folder: First, slowly open the bellows, then check that you have a view you want to photograph and set the aperture and focus. ONLY NOW do I wind on, cock and shoot.

Try putting a layer of greaseproof paper or some other thin material over the film gate with the bellows shut, then click to let the bellows open suddenly and watch what happens to the paper. Once you've seen that, I doubt if you will ever again open the bellows after you have wound the film on.

[kansalliskala]

Thank you for advice, so the air pressure disturbs the film placement.

EDIT: actually I do that exact same procedure every time, haven't just noticed it concsiosly. I never wind the film in place with this camera because the film advancement knob moves easily.

[Nesster]

You might find this interesting:

http://www.flickr.com/photos/29504544@N08/sets/72157620860652449/