Developing for scanning

derevaun

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My cheap scanner sucks. Specifically, it produces noisy highlights when the negatives have substantial density, or above 225 on the scanner's histogram (in the Epson software or Vuescan). It's worst with color, but BW isn't safe either. I can get great range if it's on the negative, as long as there's not much above that number. It appears that the POS just can't see through that much stuff without banding and noise, even if its dynamic range is comparatively suitable as advertised.

So I'm starting to develop for thinner negatives. Diafine has worked out OK, but I'm interested in PMK/Pyrocat type staining developers. I've seen several instances of "bulletproof" in descriptions of the resulting negatives. My logic may be flawed, but if my scanner can't punch through ordinary high density, it might not punch through restrained density plus a lot of brownish stain.

Any experience or suggestions? Thanks in advance for all replies except "get a new scanner chump." 🙂
 
Flatter negs scan easier than dense. Whatever your favorite developer is is what youu should stick with. Just reduce your developement times and make some tests. Adjust exposure for the shadow density and adjust times for highlight density. Remember, expose for the shadows and develope for the highlights.

http://www.rangefinderforum.com/photopost/showgallery.php?cat=5045
 
I have not found a negative that I could not scan well. It is all in learning how to use your scanner software. There are a wealth of controls in most scanner software to expand or contract the dynamic range, etc. It is also good to do the initial scan in 16 bit mode, and then make your photoshop corrections in that mode, then re-save to 8 bit. In 16 bit mode there is more data to adjust. (More depth of data).

If a negative will print in the darkroom well on #2 of #3 paper it should also scan well. If your negatives are too thin, then more dust and specks will show in the scan.
 
I've been scanning my negatives, most all my B&W prints are minilab prints of scan. Got a new toy, first one with absolutely no meter, and of course had a couple thin negatives in there. No big deal, just some cat pictures. BUT...

All these threads about scanning negatives leads me to believe that scanning deals better with thinner negatives than printing. Is this the case? I ask because there is absolutely no way I could scan this negative. Backlit cat on the back of the recliner. To look through the negative on the light box or held up, you can really only see the blinds behind the cat, and a cat shapes hole. (It's a neat effect but not one I've ever been able to pull off in a positive print.) So I'm looking at these negs, got to thinking and tried viewing them on edge for reversal viewing - it works, though it's easier to hold a 35mm neg flat and at the right angle - when PRESTO - all this detail pops out on the cat. Whiskers, stripes in her fur, eyes with pupils even. I reiterate - this neg is so thin that if it scanned at all (Automatic mode has thrown out many scans this thin) all you would really see is the blinds behind her.

Now I know the world really needs one more picture of my cat, but this is science here. Is a negative this thin even printable? I'm intrigued by the notion that film records even more dynamic range than neither traditional techniques or current technology can render.
 
Xaos,
there is a technique which I don't know the English term for (in German it is Dunkelfeldreproduktion - roughly translated 'dark field reproduction') where you light the neg at an extremely flat angle and make a repro neg from it, to save an underdeveloped/underexposed neg - I don't know how it is done exactly, though, and could not turn up anything useful w/ Google...

Roman
 
derevaun said:
My cheap scanner sucks. Specifically, it produces noisy highlights when the negatives have substantial density, or above 225 on the scanner's histogram (in the Epson software or Vuescan). It's worst with color, but BW isn't safe either. I can get great range if it's on the negative, as long as there's not much above that number. It appears that the POS just can't see through that much stuff without banding and noise, even if its dynamic range is comparatively suitable as advertised.

Any experience or suggestions? Thanks in advance for all replies except "get a new scanner chump." 🙂

It's not a risk-free solution (pun intended) but have you considered treating problem b&w negatives with a proportional reducer?

Reducers in general chemically reduce the density of b&w negatives, and a proportional reducer does this in proportion to the original amount of density. The effect is to knock down the opacity of the highlights without having much effect on the thinner shadow areas.

Incidentally, your problem (believe me, I've had it, too!) points out one limitation of film scanners vs. conventional enlarging -- in a wet darkroom, you can deal with such negatives by what one my instructors used to call a "burger-and-a-beer exposure" (turn on the enlarger, then go out for a burger and a beer.) Since most scanners are optimized for chromogenic films, it can be really hard to punch enough light through a silver-halide negative to get adequate highlight exposure!
 
Roman said:
Xaos,
there is a technique which I don't know the English term for (in German it is Dunkelfeldreproduktion - roughly translated 'dark field reproduction') where you light the neg at an extremely flat angle and make a repro neg from it, to save an underdeveloped/underexposed neg - I don't know how it is done exactly, though, and could not turn up anything useful w/ Google...
Roman

Indeed, google only gave one hit for Dunkelfeldreproduktion, and the translation was poor. It gave up somewhere shortly after "the hare in the pepper" (surely an idiom that got translated). To be honest, I'm quit suprised google didn't come back with "Find hot Dunkelfeldreproduktion singles near you" "Would you like to buy Dunkelfeldreproduktion? Generic Dunkelfeldreproduktion at rock bottom prices" rather than admit it didn't know anything.
 
XAos said:
All these threads about scanning negatives leads me to believe that scanning deals better with thinner negatives than printing. Is this the case? I ask because there is absolutely no way I could scan this negative. Backlit cat on the back of the recliner. To look through the negative on the light box or held up, you can really only see the blinds behind the cat, and a cat shapes hole. (It's a neat effect but not one I've ever been able to pull off in a positive print.)


Scan it as a color positive transparency and reverse the negative in PhotoShop. Works like a charm.

Tom
 
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