Re: paleonet Digital photography again

At 10:00 AM -0400 10/24/01, Tom Whiteley wrote:
After reading a number of the notes on digital photography I felt I 
must weigh in on the issue.

First of all no digital camera on the market today, under $6000, will 
yield a photograph with the information in film of comparable speed. 
If one wishes the optimum digital image the best way is to use 
existing photographic equipment and get a good film scanner, for 
under$1000, to convert the negative or positive to digital. The 
result will be a very high resolution, ~2700 pixels per inch, 
digital, non-interpolated image. Also one has the original slide or 
negative as a permanent record. Images of this resolution allow 
significant cropping and other image manipulations. Using existing 
equipment, usually an SLR with a macro lens, one can control depth of 
field, lighting and composition better than any point-and-shoot 
digital camera.


To throw in my $0.02, Tom is right on the money.  I pine for the day 
when the image is converted to pixels as it's collected and goes 
straight into my computer, and that day is getting closer all the 
time.  But for serious publication-quality specimen macrophotography, 
it still seems like film scanning gives you wayyyyy more bang for the 
buck.  4000 dpi film/negative scanners are now reasonably cheap (the 
current issue of MacWorld has a review roundup of seven current 
scanners, their top choice being the Polaroid Sprintscan 4000).  I 
use the Polaroid which now lists for $1,295 (I'm not sure how 
Polaroid declaring bankruptcy will affect availability, but read that 
their digital imaging was profitable and likely to be spun off).  The 
cheapest scanner in the MacWorld roundup is the Minolta Dimage Scan 
Dual II, which does 2,438 dpi for a list price of $399 - that is 
adequate for many needs, since at a publication resolution of 450 dpi 
(which is what the Journal of Paleontology and I believe all other 
Allen Press journals ask for) it still allows enlargements of x5.4 
from the negative (maximum scan dpi divided by desired target dpi). 
In my trilobite photography, I very rarely need to enlarge more than 
that (though the SS4000 allows x8.9).  For black and white specimen 
photography, the combination of Kodak Tech Pan film and a high 
resolution scanner seems like the best current option.

Scanning still takes some time (with most scanners, you can set up 
6-frames-at-a-time batch scanning), but it's a fraction of what 
darkroom printing used to take, and you get an infinitely adjustable 
result (as opposed to having to make a range of discrete exposures to 
allow for matching tone/contrast and hoping you got the right ones).

J
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Jonathan Adrain                 Managing Editor
Assistant Professor             Journal of Paleontology
Department of Geoscience
121 Trowbridge Hall             phone (319) 335-1539
University of Iowa              fax   (319) 335-1821
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http://www.geology.uiowa.edu/faculty/adrain/adrain.html
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