Re: paleonet Digital photography again

At 9:49 PM +0200 10/24/01, Stefan Bengtson wrote:
>Tom Whiteley makes a number of valid points. Still I'd say the 
>balance has for a while weighed over in favour of digital cameras 
>(and even Tom admits he's mostly digital these days):

For many purposes, including probably most purposes of people on this 
list, this is likely true.  For specimen photography, it depends. 
For relatively large specimens, stuff you'd shoot with a standard 
macro lens with or without regular bellows, digital cameras are 
probably now the way to go.  Perhaps I'm biased by my own needs, but 
for photography of small specimens - a few mm to perhaps 2 cm in 
dimension, really on the boundary between micro/macro (e.g., most 
trilobite sclerites), it's not so simple.  You ideally need quite 
specialized lenses (many of the people currently publishing 
high-quality photographs of trilobites, e.g., Harry Whittington, 
Derek Siveter, still use a Leitz Aristophot system made in the 1950s 
and 1960s [fixed camera with bellows/extension tubes to 20-35 cm, 
focussing manually using universal stage], and Milar and Summar 
lenses [which close down to f48 or f96] or else the Multiphot copy 
made by Nikon in the 1970s and 1980s).  As far as I know there is no 
way to use these with a digital camera (I would love to be educated 
if it's possible!).  Photography down the barrel of standard 
microscopes generally yields lower quality images, with sharpness of 
optics and depth of field the main problems (I do have a Pixera 
digital camera hooked up to a Leica MZ75 trinoc, but only use it for 
morphometrics; years ago I shot quite a lot with a Wild 
Photomicroscope setup, but always got better results with Zeiss 
Luminar micro/macro lenses, another alternative to Summars/Milars). 
And, for people in this boat, resolution continues to be an issue. 
With 4000 dpi negative scanning, you get 5512x3675 pixel resolution 
of a 35 mm frame.  Don't get me wrong - the sooner everything is 
totally digital the better, for the many reasons you list.  But for 
some of us, I'm not sure we're quite there yet.

J
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