Epson v750 - optimum resolution

[Richard M. Coda]

There are feet on the Epson holder and you can adjust to 0, +, or take them off. It is in the pdf manual, buried under what to do if you get blurry scans.

Jon

Damn! Now I'll have to play around with them...

[twise]

Nathan,
Regarding your resolution v distance from platen graph. If I am reading this correctly, the highest resolution is where the film is 3 mm above the platen? The resolution in micrometers means that the smaller the number, the more detail can be resolved?
Thanks
twise

[Nathan Potter]

Nathan,
Regarding your resolution v distance from platen graph. If I am reading this correctly, the highest resolution is where the film is 3 mm above the platen? The resolution in micrometers means that the smaller the number, the more detail can be resolved?
Thanks
twise

Yes you are reading correctly. But the sweet spot for maximum resolution will vary some from one machine to the next. Also note that the high maximum resolution number I measure on that plot was made by adjusting the contrast to the highest possible in Photoshop then examining the line pairs at 1600X. If one preserves the full tonal range while scanning and in PS the resolution will be much lower because, in effect, you will be exchanging a high contrast image for a wide density range image.

If you are a bit non-technical then consider: 1 micron (1um) is 1 millionth of a meter.
There are about 25 um in 1 thousandth of an inch (.001 inch). Most high quality imaging lenses can resolve around 5 to 10 um feature sizes using white light. Using monochromatic light close to 1 um can be resolved.

Nate Potter, Austin TX.

[SeanEsopenko]

I use the epson holders for 4x5 because I'm not printing anything with crazy enlargement when shooting 4x5. I do have betterscanning.com holders for the 6x7 I shoot.

I found with the aftermarket holder a difference of a quarter turn (0.25mm) makes a difference in sharpness. I also scan at 6400 dpi (even 4x5, yes) and down-sample to somewhere between 2000 dpi and 2400 dpi. I see a marked improvement in detail when I do that.

I don't have a large enough inkjet (R3000) but I've printed 8x10 crops of a simulated 20x24 print and for what it's worth the inkjet is the weak link when printing a scan of a 4x5 transparency and observing the sharpness. I can't print optically any larger than 16x20 and honestly I'd never be able to sell anything larger than that for a long while so I don't have much to say regarding large prints.

But I can confidently say that the betterscanning adjustable holder improved my scanning immensely for 6x7 (which is subjected to much more magnification than 4x5 work I do).