Originally Posted by Pere Casals
Why not ?
Just scan a USAF 1951 resolution target slide and post the scan.
https://en.wikipedia.org/wiki/1951_U...ion_test_chart
If group 6 element 2 bars are seen then your system is outresolving LF lenses, so enough for LF sheets. If you see Group 7 elements then you have a first class system...
Here you have the result from an X5 (Not a drum, but close, This is scanning 35mm):
You can compare to that.
Other practical tests can be done with an IT8 slide target, for density, etc, Also you can measure stray light.
https://www.flickr.com/photos/timpar...125592977@N05/
IMHO numeric tests do not explain all but a lot is explained...
Fair enough. The last AF test target scans I made on several D4000s and a Tango resulted in a resolution figure a little better than about 4300 dpi. I forget the formula for translating between the Air Force target and DPI. Anyone have that?
I'll do a D800E scan of my AF target this weekend and post the results.
I'll also scan an IT8 target. I'm not sure how much that would satisfy the question. It's a reference target and using its calibration file will certainly produce a color reference frame for a particular machine, but I don't think individual machines can be compared to each other by looking at their images of different IT8 targets. Someone set me straight if my logic is off here.
FWIW, producing scanner ICC profiles from an IT8 target never really helped me with any scanner I've used. It always resulted in crushed blacks, despite the Don Hutchinson "trick" of covering the darkest patches on the target with metal foil tape to make them absolutely opaque. Scanning without a scanner profile and subsequent color correcting on a calibrated monitor, using the original transparency transilluminated by daylight/calibrated light source, or by comparing to known reference images on screen was always much better.
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