[GerryL]

DOF are really a world apart when it comes to FF and APS-C.
Even if you use the same lens and move back to get the same framing as the FF film cam, the curvature or the juxtaposition of the objects in the chosen space wouldn't just be the same.
A 50mm shot with a FF would have a more spacious feeling than with a backed out 50mm shot with an APS-C, as the space just becomes compressed just like in a zoom lens.

[Robert S Donovan]

DOF are really a world apart when it comes to FF and APS-C.
Even if you use the same lens and move back to get the same framing as the FF film cam, the curvature or the juxtaposition of the objects in the chosen space wouldn't just be the same.
A 50mm shot with a FF would have a more spacious feeling than with a backed out 50mm shot with an APS-C, as the space just becomes compressed just like in a zoom lens.

I agree. I bought an FA 35 f/2 to try and get that 50mm look but everything ends up kind of distorted and I can't get the DoF the way I want it. One has to realize that an APS-C sensor is just using less of the image circle than full frame. Therefore, the DoF of a given lens will be closer to what you would get on FF than what its equivalent focal length is.

For example, an on-line DoF calculator shows that my 35mm lens at f/2 has a total DoF of 0.49' @ a 5' focal distance when mounted to my K10D. The same lens provides 0.73' of DoF on a FF camera. Meanwhile, my 50mm lens at f/2 provides 0.24' of DoF on my K10D and 0.35' on FF. Therefore, even though my 35mm lens approximates a 52.5mm lens on my APS-C K10D, it gains 0.14' of DoF over a 50mm lens on a full frame camera in the same circumstances. (The difference is 0.04' greater for a 52.5mm lens on FF, BTW.)

This may not seem like much but it turns out to be a lot in the shots I take. I'm still waiting for an affordable ≈ 35mm f/1.4 lens to replace the missing nifty fifty equivalent Pentax's DA lens lineup.

[shaolin95]

Nice, although I am sure the K-7 will fair a lot better I am looking to get one of those k1000 just for fun, interesting to have on board. :-)

[Rich_A]

Big difference in the processing requirements between digital and film. This is a useful exercise but I have a hard time accepting the assumption that digital is worse than film simply based on results from an older digital camera. Compare the results from the K-7, D90, 50D or any of the current offerings from other manufacturers and it's a much more difficult prospect. Film isn't bad, it's simply less flexible unless you scan the results and post-process them in the computer. Anyone ever tried recovering highlights from a slide like you can with a DNG file from a digital camera? Again, digital isn't better it's simply more flexible than slides. I would agree that very fine-grained negative film, especially B&W has much greater dynamic range than digital and gives a much more impressive result "out of the box". Some solid training in B&W conversion in Camera RAW, however, and I can do almost anything I can imagine with that same frame in a digital format.

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Last edited by Rich_A; 08-28-2009 at 01:47 PM.

[snogglethorpe]

A very interesting and thoughtful test!

One thing that's immediately obvious is that the curves are very different (e.g., the film seems much more contrasty).

It would be interesting to play with PP to try and get a film-like curve from the digital images, and see how far you could get with that (maybe would run into dynamic range issues?)...

[farfisa]

Thanks for doing this! Very well done!

[three]

BTW, great place this forum, great images, great photographers and great reading, "long-time-reader, first-time poster" over here. Not a native English-speaker, sorry for that.
This great thread made that I must post after reading it, say HALLO...
I finally got it what is all about, I think!!!
For me, as i see it, it's not about colors and contrast that much (because in digital, you can make any color you like, in PP), but, its more about cropping the image circle and its negative effects on the prespective and FOV, and also quality of OOF and InFocus, and also In-Focus-Out-Of-Focus separation, and also lack in the wide angle, and adding distorsion in images taken in "normal" (human) field of view around FA 43mm lens. It is not dependant if you have old istD or new K-7 as long as they are using same aps sized sensor. Now i got it!!! If some lens is developed 50years for film negative size, to achieve requests of top artists photographers, of course that it will not produce equaly good results on 1/2 of the film negative - aps-c size. Because, it is like using only the falf of the resolution of that lenses.......Well, but that is the best way to sell new lenses, and make profit. Its clear.

Thank You. This is like a pictorial guide to understand what techichal "evolution" (!) is doing to the Art. There are enough examples for that.