90mm/4.5 Grandagon-N and Filters

[W.Ferrier]

I have not had any problems using 82mm filters on my 90 mm 4.5 grandagon. Never had any viignetting using it on my 4x5. It does not touch the front element either so no spacer is needed (unlike the110 schneider )

Arthur-@ what f/stops do you normally shoot? I have that lense on a fotoman 6x24and I used f/16 & an 82mm polarizer and had vignetting problems. Would going to f/22-45 help eliminate this problem?

Thanks in advance,

Bill

[Bob Salomon]

[QUOTE=W.Ferrier;Would going to f/22-45 help eliminate this problem?

Thanks in advance,

Bill[/QUOTE]

It would get you into diffraction much past 22.

[Bob Salomon]

Arthur-@ what f/stops do you normally shoot? I have that lense on a fotoman 6x24and I used f/16 & an 82mm polarizer and had vignetting problems. Would going to f/22-45 help eliminate this problem?

Thanks in advance,

Bill

Actually as you stop down the coverage of the lens would increase. That would not reduce vignetting. Going to a very thin step up ring to 105mm and then using a slim 105mm polarizer might eliminate vignetting from the polarizer.

However, when using a polarizer in ultra wide shots that include large areas of sky you will get banding in areas of the sky.

[W.Ferrier]

Bob-thanks for that information-the banding problems have been an issue and I had no idea what caused it. So then is f/22 "kind of " the recommended/most used f/stop in the large format lens? Thanks again,

Bill

[JPlomley]

I will be getting some tests back tomorrow. Checked the lens with an 82mm B+W warming filter (not a slim line), then with a Heliopan 82/105 SUR and B+W 105 WT-Polarizer (not a slim mount), then with a Lee 82mm wide angle adapter ring with one slot for a GND filter and the front fitted with the 105mm ring to which I attached the B+W polarizer. My shooting style dictates focus spreads which can only be accomodated with apertures of f/22. When I tested this optic against my 135 APO Sironar-S at f/22 (no filters), performance was similar.

[JPlomley]

Forgot to add that I am shooting 4x5. 6x24 could be an issue as you are much closer to the edge of the image circle.

[Bob Salomon]

Bob-thanks for that information-the banding problems have been an issue and I had no idea what caused it. So then is f/22 "kind of " the recommended/most used f/stop in the large format lens? Thanks again,

Bill

Beyond f22 you will be into diffraction.

[JPlomley]

Beyond f22 you will be into diffraction.

Yeah, but in my experience so far with the lens, it performs exceptionally well at f/32. I'd rather take the moderate hit in performance due to diffraction than the loss of depth. OOF areas that should be in-focus just bug me alot. Also, if you are scanning your chromes and using good sharpening algorithms, you won't see a difference between f/22 and f/32 in the final print.

[arthur berger]

Most of my photographs with this lens have been taken at either F 22 or F 32. I use a regular 82mm filter- either tiffen or B+W. I never had a problem with vignetting. A polarizer might be a little thicker and maybe that could cause a problem. 6x24 format may be another story however and may be approaching the outer edge of the coverage.
Arthur

[W.Ferrier]

Thank you all for your input- I need to read up on image circle issues. Do you folks ever shoot @ f/5.6-f/16 with this lens ?

Bill