Monday, September 13, 2010

Utility Pole in HDR - As good as Kodachrome?

I have a photographer pal who is a forever film man.  For him, film has qualities that cannot be equaled, let alone beat, by digital capture.  For my part, I have gone completely over to the digital dark side.  My favorite emulsions and papers are gone forever, so for me, there is no looking back.  Still, it is fun to debate the relative merits of film and digital.  I must concede to my friend that there are desirable intangibles inherent to film that requires considerable extra effort to match with digital.
This picture of one of my favorite subjects, the ubiquitous utility pole, has the detail and color saturation that reminds me of the most recent casualty of the digital juggernaut, Kodachrome, the color film gold standard since 1935.  How close is it?  I thought it was time again to take stock.
First, let's talk resolution.  I think it is generally accepted that a good 35mm Kodachrome 25 shot has the equivalent of 20 mega-pixels.  This picture is an HDR shot made up of three layered 12 mega-pixel DSLR captures.  It is not truly the equivalent of a 36 mega-pixel capture, but it gets pretty close.  Flagship DSLRs are capable of exceeding Kodachrome without HDR technique, so digital wins this round.
So how about color?  Kodachrome was, of course, analog, so comparison with a DSLR's discrete color capability is difficult.  For the sake of comparison, lets say projected Kodachrome slide has roughly a 24-bit color range, which matches the capability of the human eye to discern color.  The pro DSLRs capture 14-bit color and interpolates 16-bit.  HDR technique combines RAW images to 32-bit, then flattens the final output to 16-bit.  The digital clipping and interpolation falls short of film.  However, if we compare a pro quality inkjet print to a type-R print, the color gamut and contrast range of the ink jet wins.
So, in the end, I miss the idea of Kodachrome, but the truth is that I haven't shot a roll for more than 17 years.

Camera: Nikon D700 
Lens: Nikkor AF-S 50mm f/1.4G 
Exposure: ISO 200, three brackets around f/11 @ 1/200s, tripod, RAW
Lighting: Daylight  
Location: Grand Center Artist Loft Studios GPS
Processing: Lightroom 3, Photoshop CS5 HDR Pro

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