Re: [APML] DWB111 Comparison

[Gene Horr <genehorr@texas.net>]

Chuck Vaughn wrote:

> Besides the advantage of very low noise there seems to be another
> issue I have not seen addressed: Film looses resolving power at
> low contrast levels.

Some of this may be due to (1) 14 - 16 bit ADC for most astro cameras 
versus 8-12 bit ADC for most film scanners which by itself would give
you better contrast across the entire range, and (2) the chip & ADC
are designed in CCD cameras for low noise.

I would hazard a guess that most (all?) affordable film scanners are
optimized for the average light exposure.

A film scanner optimized for astrophotography might capture this information
which might be on the film.  But it would likely cost $10,000+ as the market
is counted in the dozens of units <g>.

Gene Horr
genehorr@texas.net

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