Let me start by saying I don't have a darkroom nor a proper densitometer (although I have been thinking if i need one)
I would like to perform some tests to see which zones the scanner can actually resolve detail on my 4x5 negatives.
Is it possible to use one sheet of film, and expose a textured surface several times at different shutter speeds by moving the dark-slide out a certain distance between each exposure.
That probably works, the problem will likely be the speed at which you can consistently draw the darkslide, getting as long of a exposure as possible will help there.
I would adjust aperture instead. Likely to be more accurate than shutter speeds, and your lens may have 1/3 stop markings for fine tuning.
You will probably find this earlier thread helpful: Scanner-performance-v700-and-Vuescan-Pro-in-relation-to-step-wedges
The Epson V800 appears to have the same performance as the V700 which I tested: it has more than enough dynamic range to handle typical B&W negatives.
Thanks Ken for the link, appreciared
Did you ever get the scan to represent the stoufer Ken in terms of linearity, or did you not pursue it any furtherOriginally Posted by Ken Lee
I didn't pursue it. I took Peter De Smidt's good advice.
All you need is a Stouffer density scale. They comes in all sizes and shapes. Get the one that fits your scanner and has the increments that work for your needs. Details at:
http://www.stouffer.net/using21step.htm
In the above-cited thread, it was helpful for me to find out that the scanner could accommodate that step-wedge.
However, in that thread Peter pointed out that because we usually add an adjustment layer to each photograph, calibrating against any step-wedge whose density range is different from our usual film may be of questionable value. Having 2 curves instead of one may even degrade the tonal scale a bit.
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