IQ180 on Sinar P2, with Kapture Group adapter, Schenider Lenses

[photoparty]

Does anyone have any experience using a Kapture Group Sliding Adapter with an IQ180 with a Mamiya mount and Schneider Digitar lenses? I've been having some issues, all four of my lenses are producing images that look, for lack of a better word, "crunchy". Despite walking the lenses back and forth, I can't find a truly sharp point.

My previous back, a P45+, gave excellent results with this setup (though it had a Hasselblad V mount).

Is it possible that the Schneider lenses simply don't have enough resolving power for the IQ180? My lenses are: 100/f5.6, 120M/f5.6, 60/f4 and 80/f5.6 all mounted on copal shutters.

 

[Jack]

I have used a P2 with a Betterlight scanning back. I quickly learned it was not rigid enough between the standards for extremely high resolution digital imaging. My guess is this was likely due to the height and extreme adjustability on each standard, and equally likely why they came out with the smaller, tighter P3 for digital imaging.

The 120 should be fine, but the 100 and 60 do not have the best reputations as compared to modern lenses. Even with my newer 70 HR-W, I can see areas in the edge of the IC where the back is outresolving the lens*

Since it worked with your P45+, it could simply be you are at a point with the IQ180 where you are resolving more than the lens/camera combo can deliver.

*This fact tells me we are probably very near or even at the limits of practical resolution with the 5.2U backs.

 

[dougpeterson]

My guess is you're not taking into account a lower diffraction limitation with smaller pixels.

If for instance you're using f/16 on these lenses (which could be pretty decent with a 45+) I'd expect pretty soft results (as viewed at 100% pixels - not as viewed at a given print size).


Doug Peterson (e-mail Me)
__________________

Head of Technical Services, Capture Integration
Phase One Partner of the Year
Leaf, Leica, Cambo, Arca Swiss, Canon, Apple, Profoto, Broncolor, Eizo & More

National: 877.217.9870 *| *Cell: 740.707.2183
Newsletter | RSS Feed
Buy Capture One 6 at 10% off

Masters Series Workshop:
New England Landscape - Fall Color (Oct 5-8)

 

[photoparty]

I tested the 100mm and 120mm from wide open all the way to f16 and got the same results, it's overall slightly out of focus. I had 125k captures on the P45+ when I traded it in, the vast majority with those two lenses, usually at f16. They were both very sharp. I would love to get back to using a view camera, but in the meantime I've been using a Mamiya 645DF primarily with a 120mm Macro (not the "D" series).

Any recommendations on a view camera lens that I might try testing with? I rarely use anything wider than an 80.

 

[gazwas]

You probably know all this but........

Do you have the noise settings too high, smudging the detail?

Are you shooting flash or tungsten as I have noticed with my P65 and Arca ML2 if you stab at the cable release you can cause the camera to move slightly and camera shake on these newer chips makes a big difference to image sharpness.

 

[dougpeterson]

I tested the 100mm and 120mm from wide open all the way to f16 and got the same results, it's overall slightly out of focus. I had 125k captures on the P45+ when I traded it in, the vast majority with those two lenses, usually at f16. They were both very sharp. I would love to get back to using a view camera, but in the meantime I've been using a Mamiya 645DF primarily with a 120mm Macro (not the "D" series).

Any recommendations on a view camera lens that I might try testing with? I rarely use anything wider than an 80.

Gotchya, well then as otherwise suggested camera shake, tripod/head stability, flash duration (if camera or subject are moving), focus error, and a lens' maximum resolution all matter considerably more when you double your resolution (39 megapxiels to 80 megapixels).

I'd recommend the Schneider 120mm Macro for any macro work - fantastic lens within it's intended macro magnification range.

 

[cng]

The 120 should be fine, but the 100 and 60 do not have the best reputations as compared to modern lenses.

I use the 100/5.6 Apo-Digitar on my Linhof m679CS + IQ180 and am very happy with it. In fact, the MTF charts for the 100/5.6, 120/5.6N and 120/5.6M show similar theoretical resolution performance.

The older 60/4 has always been a bit suspect, but the newer 60/5.6 – which I have for both my Linhof and Cambo WRS – is an excellent lens.

YMMV.

 

[Jack]

My money is still on the P2's relatively "springy" rigidity between the standard frames...