Dynamic Range

Such a sweet image, Ray...and a wonderful story of your kids' "participation" in the process!

As far as film vs. digital DR goes: I know that digital can do the deed if you're willing to sweat the details, which aren't minor, and have often driven me up the wall, whereas with film, I simply set a few parameters for myself, and off I go. This image reminds me of why I continue to do things the way I do. Not the only way, but, to me, the sweetest way.


- Barrett
 
Inspirational photo for me ... that image has everything I aspire to with my black and white photography.

Thanks for posting! :)
 
Saying a DSLR has 10 stops of dynamic range sounds impressive, but that still only amounts to a 1024:1 ratio, which is considerably less than many common real-world situations, and (as experience tells us) less than b&w film can capture with careful exposure and development.

And while a 10-bit or 12-bit film scanner in theory shouldn't be able to extract any more dynamic range from the film than a digital camera can extract from the original scene, in practice you can get more range out of the film for two reasons: (1) the film's contrast curve already has compressed the tonal information to some extent, and (2) if necessary, you can scan the film more than once at different settings to extract detail out of both the low-density and high-density areas.

This is roughly equivalent to making multiple bracketed exposures with a DSLR and then assembling them into an "HDRI" image. However, with film you don't have to worry about objects moving between exposures! Dye-based films generally have a low enough D-max that this trick isn't necessary, but when scanning conventional silver-based films I often scan them two or even three times to get good tonal distribution in the shadows, midtones, and highlights. I put the three scans in separate layers in Photoshop and adjust their opacity until I get a full-range image; I can also use layer masks to make localized corrections to areas that need to be lighter or darker, without the loss of detail that occurs when using Photoshop's 'dodge' and 'burn' tools.


I shoot almost 100% digital now for time reasons, but I often find myself shooting in places where I used to use film, and I've learned to accept highlight "blowout" under conditions that I know from experience I would have been able to "save" when shooting in the same type of situation on film.
 
I agree with the enthusiastic comments on the dynamic range. I also wonder how close one can match this range with color negative. If you try Reala it will surprise you on this side. Also there is a terrific Agfa of which I don't remember the name and I am not sure it is still in production. They can do miracles on the underexposed side. So one has to be careful on highlights and dare. The results (of reala) really impressed me
 
DD for DSLRs is 10 stops technicly only. I would say more, DD for MF backs more then 10 stops (technicly). But curve for DSLRs' DD works good only for medium range of DD. For highlights matrix has ability to capture but in most situations its outside of 12bits. For dark shadows matrix can capture image too, you will get a lot of noise, because level elecltical signal will be the same as a level of random thermal noise. As a conclusion I would say, that working DD for DSLRs is 7 steps and for MF backs around 9 steps (because MF matrix have more area and less level of thermal noises)
 
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