First scans with Epson V850

[Alan Klein]

First is that you can make a contact copy of the 35mm target on 4x5 film, I'd recommend ADOX CMS 20 sheet film for that, other low ISO may also be good, and TMX. Use any cheap microscope, to check the result.

Then you can take a caliper and use the same bed to film distance for 4x5 than for 35mm, as 4x5 and 35mm scanning uses the same lens. When using thae area guide the Epson uses the Low Res lens, that I think has the focus on the bed itself.

Isn't the low res lens for scanning prints since you have much less need for pixel resolution? So the holders keep the film (4x5, 35mm, 120, all up at the same distance when scanning with the high res lens?

[Alan Klein]

48bit is 16bit x 3 channels ; 24bit is 8bit x 3 channels...

IMHO for negative film you can use any software, but with velvia/provia you may want a soft featuring Multi-Exposure in case that you have deep shadows and you want to recover it

For 8x10 you'll have to do it "on bed", no other choice, then wet scanning solves the newton rings, but by placing emulsion side to the glass it also works.

For 4x5 IMHO best way is holders, the wet mounting is good if dust or scracthes are there, but you have to control dust with an HEPA air purifier, and scratches by careful process...

Wet mounting film may be good sometimes, but it's also a pain.

How does multi exposure work? How will a second exposure allow more light to go through the shadow areas? Is the V850 light source adjustable?

[Ted Baker]

How does multi exposure work? How will a second exposure allow more light to go through the shadow areas? Is the V850 light source adjustable?

By varying the amount of time allowed for the CCD to collect photons (light) before the device is "reset" to take the next exposure.

[Alan Klein]

By varying the amount of time allowed for the CCD to collect photons (light) before the device is "reset" to take the next exposure.

Why not set the longest so you always catch the full amount in one scan? Isn't the unit calibrated by the manufacturer to catch that anyway? (the dmax). Just scan at the maximum potential, dmax, of the scanner and you'll get the shadows first scan. Why lower it to create extra scans?

[Pere Casals]

Why lower it to create extra scans?

CCD (like CMOS) sensors have lower dynamic range than PMTs in drums, one way to overcome that is Multi-Exposure, V850 with right software (SF SE plus, for example) can make 2 scans with different exposures and then both results are combined to get a larger range.

Other expensive scanners (I guess) may make the 2 exposures before the carriage advances to next row.

If you have a very dense or a very thin film, without much dynamic range in it, then you can save a pass by adjusting the right exposure, and still having best results possible.

IMHO adjusting exposure is not always useful, but it can be sometimes.

V850 is not Pro gear, perhaps it's semi Pro, and it has some limitations, but in the hands of an skilled user it can deliver amazing results that are far beyond we can guess from its cost, in special with LF formats.

[IanBarber]

CCD (like CMOS)

If you have a very dense or a very thin film, without much dynamic range in it, then you can save a pass by adjusting the right exposure, and still having best results possible.

IMHO adjusting exposure is not always useful, but it can be sometimes.

With the V800/V850, is setting multiple the exposure option the only way to adjust the exposure or are there other ways within the software

[Ted Baker]

With the V800/V850, is setting multiple the exposure option the only way to adjust the exposure or are there other ways within the software

Vuescan, with the RGB/Infrared exposure on the input tab, is the only one with manual control that I am aware off, epson and silverfast may it do automatically as part of the preview pass.

[Pere Casals]

Vuescan, with the RGB/Infrared exposure on the input tab, is the only one with manual control that I am aware off, epson and silverfast may it do automatically as part of the preview pass.

It should be like this.

With epson and sf you have Continuous Auto Exposure, Recommended Value, and Auto Exposure Level options, so the auto behaviour can be modified away from the "recomended" setting, this works fine, but it's great that Vuescan has that direct adjustment, I like it.

[IanBarber]

Vuescan, with the RGB/Infrared exposure on the input tab, is the only one with manual control that I am aware off, epson and silverfast may it do automatically as part of the preview pass.

I am guessing this is a balancing act as I would think setting this value to high could affect the areas of the negative which are dense (brighter areas)

[Steven Ruttenberg]

Here is an example of a scan from the V850 at 4000 dpi and AA off. 5x4 Extar 100

http://www.steveruttenbergphotograph...65f4#ha65765f4

How do I get larger images to post to the thread? The limitations don't allow for a very big image, dimension wise that is. I see some fairly big images in the thread.