Thin or dense negative better to scan?

[Ted Baker]

What variables that are being ignored or misunderstood are you referring to?

Variables that I can think of:

1. BW versus colour, the base of the red layer is already dense, 1 stop or about .7D. Does the exposure of the scanner allow for this. (or is it even necessary for the particular negative)
2. Does the scanner have sufficient resolution, film does not record intensities on a linear scale, is there sufficient bit depth and accuracy where it is needed. This is particularly relevant for a negative.
3. CCDs are not perfectly linear or noise free over the entire scale, they have a noise floor.
4. How the film itself responds to greater exposure.

Your scanner when operated correctly, may well be very capable of giving good results with dense negatives. Just saying

 

[holggger]

Variables that I can think of:

1. BW versus colour, the base of the red layer is already dense, 1 stop or about .7D. Does the exposure of the scanner allow for this. (or is it even necessary for the particular negative)
2. Does the scanner have sufficient resolution, film does not record intensities on a linear scale, is there sufficient bit depth and accuracy where it is needed. This is particularly relevant for a negative.
3. CCDs are not perfectly linear or noise free over the entire scale, they have a noise floor.
4. How the film itself responds to greater exposure.

Your scanner when operated correctly, may well be very capable of giving good results with dense negatives. Just saying

Well it seems to me that 1., 2. and 3. all fall into the same category: digital sensors are bad at capturing information in the dark end of their range. The only way I can see you could fix that is by giving them more light. How would you do that when the negative stays dense as it is? Longer exposure, higher light intensity, larger aperture (depending on the scanner). Of course that would blow out thin negatives, so how do you tell the scanner what the optimal exposure range is? By telling it the white and black point before scanning...

Or so my thinking goes, and I am not confident this is how it works – which is why I started this thread in the first place, to 1) find out the best practice for scanning dense negatives and 2) to find out if I should change my film exposure/darkroom printing "workflow" (I prefer to wet print dense negatives but the more I shift from wet printing to digital printing the more it might make sense to shift to thinner negatives, as well - IF they really give better scans, which some people here disagree with. And I am still confused as to why some people find thin negatives give better results, and some prefer dense ones when scanning).

 

[Ted Baker]

How would you do that when the negative stays dense as it is? Longer exposure,

Longer exposure, and indeed longer exposure for each channel. For single pass bring the exposure up at least to the base of the film, or even further to minimum density within the frame. Vuescan does this automatically with the epson flat beds as an example when scanning a negative, or you can do it manually (but you need to look for it). You could use the same techniques with a DSLR.

Plus there is the mulitpass approach, so devices can do multipass in one pass, your phone for example may feature such technology.

I do not know about the imacon, but this suggested that it does have ability to control the exposure. http://www.martinzimelka.com/homepage/Blog/Entries/2014/10/3_Imacon_FlexColor_Adaptive_Lighting.html

 

[Mainecoonmaniac]

I don't know much about scanners, but it seems that it's digital technology is not a fix for poorly exposed or poorly developed negs. Negative analog film tolerates over exposure better. In the darkroom, one can burn in dense highlights to a certain extent.

 

[lantau]

For repro with a digital camera, copy stand and light plate it's not problem to have dense negatives. That's also important for colour slides. I simply adjust the exposure until the histogram is as good as it gets (camera is tethered to a computer). It makes better use of the dynamic range of the sensor and hence should give better tonal resolution. If I understand it right that dense negatives are better for use in the darkroom then both my positive processes are in perfect harmony.

But I'll get one of those newer Kaiser light plates at some point. They can be dimmed, which should help with some slides. The dynamic range between the super bright backlight and the near perfectly black shadows possible with E6 film can blow out the highlights in some very contrasty scenes. Pushing the HDR button would probably solve that but I'm so behind on negative film that I hardly digitise any slides at the moment. I can already see what's on them with the naked eye.

 

[WilmarcoImaging]

+1 for thinner negatives when scanning. Agree with SG to expose at box speed. When scanning+postprocessing, it's easy to lose the highlights. Best to have thinner rather than denser. Agree with jnanian that it is fun to optically print dense negatives! Haven't done that in a very long time.

 

[holggger]

I do not know about the imacon, but this suggested that it does have ability to control the exposure. http://www.martinzimelka.com/homepage/Blog/Entries/2014/10/3_Imacon_FlexColor_Adaptive_Lighting.html

Thank you Ted, this is fantastic information! In the manual this option is hidden – all it says about it is this sentence: "If your originals are very dark you can use this setting to increase the exposure time (older scanner models will increase light intensity)."
Does not seem to give more than one stop or so of exposure, but I am very much looking forward to trying this feature on dense negatives – seems to be the only exposure control the Imacon has.

 

[removed account4]

with the umax1200 scanner, IDK in 1997 vue scan was able to adjust
the intensity of the lid so dense negatives had a chance. someone should write
a patch/app whatever so every scanner has a rheostat adjustable / dimmer switched lid
it shouldn't matter too much if the color or tonality is a little screwy, seeing
pretty much everything gets edited in some sort of magic dust anyways...

 

[Ted Baker]

Does not seem to give more than one stop or so of exposure

For single pass, you can only increase the exposure up to the least dense part of the capture. For the Epson V750 it makes a difference, on another forum some tests showed this But you may indeed find that the software already does this, for example Vuescan works this way with a suitable scanner. All of these CCD devices have in effect an electronic shutter, which in many cases can be varied.

 

[NJH]

Dense B&W negs can result in awfully grainy looking scans. Given that one can be fairly nuanced and clever with the sharpening and contrast control in software there is nowt to be gained from a dense negative in this workflow IMHO.