Color or grayscale for scanning B&W film?

Color or grayscale for scanning B&W film?

  • Color

    Votes: 92 28.7%

  • Grayscake

    Votes: 229 71.3%
  • Total voters
    321
I've tried both. I reckon that if your target is the the same bit depth (say 16 bits), then scanning at 16 bit gray, or at 16-bits per color RGB and converting to gray afterwards, should get you the same results either way - as every pixel you scan is gray, you should get the same level in each color channel (if it didn't give you that, the gray scan would actually be colored). And when I compare scans done both ways I can't really see any difference.

But the difference comes if you might want to adjust the color channels before converting to gray. I'm not really sure what the benefit of that is (but I know some people do it). But as I haven't had any desire to do that, I currently scan grayscale, with the plan that if I should ever want to try adjusting the color channels in any scans I've done (assuming I find out what the purpose is), I'll go back and make an RGB scan.
 
Color 16 bits; get as much data as possible then weed it out
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That's something that puzzles me a bit - you get more data using color scanning, but do you get more information? (The two are not the same).

What I'm thinking goes like this (I'm using 8-bit values just to keep the numbers simpler): Suppose you scan a gray pixel (they're all gray - it's a B&W neg) that has a density of 128 (on a scale of 0-255). If you scan grayscale, you get a result of 128, but if you scan RGB you get a result of (128, 128, 128) - the latter contains no more information than the former.

Does that make sense?
 
Here's what happened w/ me. I was using a Nikon V ED film scanner, and scanned in a B&W neg from Ilford HP5 using the color setting, then using the mono setting (whether this is the same as your Epson's grayscale setting I couldn't say). The color setting resulted in an image that definately had more detail and looked quite different. But I found that I didn't like it as much as the mono scan, which looked more like what I consider a B&W image to look like from conventional B&W film. I tried this on several negs to make sure this wasn't image specific and came to the same conclusion. After that I did all of my scans in mono mode. Over the course of a few years I've tested this on other negs and always get the same results.

I also tried scanning in the negs using the Nikon's default 8 bit mode, then using it's highest 14 bit (per channel) mode and saw no difference in the images on my monitor. To make sure, I printed the images at 13 x 19 and saw absolutely no differences. Maybe for color, but not for B&W.

I think this is the only way you are going to get meaningful results from your Epson. Sit down and devote several hours to experimentating w/ the different scan modes and see what works best for you.

I am assuming you are going to be editing the images in Photoshop or a comparable image editing program, and not printing direct from the scan. You will see that this is where you are going to see the biggest difference in how your image eventually looks. It took me a long time to figure out how I wanted the shots to look using channels, curves and all sorts of tools, but now that I have it down I can go into the program and optomize my images very quickly.
 
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drewbarb said:
The thing I have found makes the biggest difference is to scan negs as positives in the highest bit-depth available, and invert later in PS to get a positive image.
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I've tried this a couple times with my different scanners and with using Vuescan, Nikonscan and Epson Scan and simply never found any benefit or difference in the end result that I could see. I read articles that show how in theory it should make a difference but I just never seen it.
 
I've tried scanning b&w negs by every possible way over the years.

I have concluded that scanning at a greyscale negative is as good as anything else.

The scanner initially captures the same basic data, no matter how you do it. You cannot change that. It captures RGB data. The scanner software combines those channels into a grey scale file that it outputs. Same as you later do in PS. The scanner software can output that data as either a positive or negative. Same as you later convert in PS. Therefore no difference if the scanner software works well. I use Vuescan and it does work well.

Again, the key thing is that the scanner initially captures the same data from the film regardless of how it later manipulates and outputs it.
 
Marsopa said:
I'm a complete newbie in sacnning... I've bought a plustek for home but unfortunately I don't have time to play with it. I've done some scans using a flatbed epson, here two examples, first ilford hp5 scanned as B/W negative in greyscale:
2181128211_83669d1976.jpg


and 2nd, ilford delta 100 scanned as B/W negative in 16b color:

colistin005df4.jpg

Another question I've noticed using the plustek is that scanning in 16bit color a B/W negative noise is mainly comprised in the blue channel being the other two much more clean.

P.S. Please forgive me for the awful english usage I've
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This is precisely what I am wondering about: the color tones on these two images are completely different. If you were to scan the second image as grayscale, would it still look the same? Or would it look closer to the first image?
 
I've always scanned my Tri-x in B/W mode. However, lately I haven't been too happy with my current film and developer combo. (lab processed with Xtol)

Just last week I came across one theory (written by Michel Pollet) of scanning using 8 bit B/W mode and scanning at max. resolution. According to the author, scanning in 8 bits will give less noise and a smaller work file. He also mentions about scanning to a JPEG (not really sure if I agree about this point) to save space on your drive.

So far I've been quite happy with the result, both on screen and printed on either a Lambda or inkjet. I'm looking forward to trying with other various of film and developer.

You can read Michel Pollet guide to B&W scanning here:

http://oomz.net/bw_workflow/
 
I scan B&W as grayscale, it gives the same information in a smaller file size. Which becomes significant when scanning at higher pixel densities. The one time I scanned as a color negative I didn't just get a color cast, the scan was black and orange! When desaturated, it blew the midtones into a uniform gray. (coolscan 9000)

That said, I don't tone my images in PS (I don't tone them at all), the printing drivers that came with the Epson R2400 have a feature for toning that seems to work well on the few occasions I've used it.
 
Michael Pollet's scanning tutorial is the one I've modelled my workflow after. It seems to work very well for me.

One thing that has helped me with consistency of appearance is calibrating my monitor (or simply loading the calibration profile) for sRGB. My output from the scanning/processing sequence is in sRGB so things look similar.
 
iamzip said:
This is precisely what I am wondering about: the color tones on these two images are completely different. If you were to scan the second image as grayscale, would it still look the same? Or would it look closer to the first image?
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I've done the test and yes, it looked very similar to the first image. I' going to have a lot of time to do tests (I've just get a hip replacement so I'll have two or three months without working), I'll post results ASAP (today I'll left the hospital)
 
IMHO scanning in color allows for better control of highlights and shadows by manipulating each channel separately. Not that it can't be done through curves in most well exposed negatives, but the manipulation of color channels seems to provide a wider range of possibilities especially in less well exposed images.
 
???

Michel Pollet's tutorial seems very interesting for me.
I use Quadtone rip for printing with Epson R800 which asks for tiff files.
Should I just convert from jpeg to tiff in the end? Or will I loose quality?
I know I could try myself but maybe I can save expensive ink and paper
if someone has the knowlege...?
 
I use Michel's tutorial as well, BUT I use Tif right from the start. I am not concerned about speed or space of my computer and prefer not to damage any pixels. I only use JPEGS for the web - everything else is either PSD or TIF.
 
Scanner: Minolta Dimage Scan Dual III
Setting: B&W positive, 16bit depth
Postprocessing: invert, adjust black and white point in levels dialog

That way I capture most of the information that is on film, without clipping highlights or lost shadows (which is the problem with B&W negative setting). Thanks to the 16bit depth even if I adjust curve, the histogram doesn't look like a comb.
 
I agree with scanning as a positive then inverting. These settings capture more information at the time of the scan and do not lose them in the inversion process.
 
I scan as positive and invert in photoshop to b&w.

But depends on your negative, for Fuji b&w I can see it is better scanned in grayscale directly.
 
A few years ago I posted some comparisons between scanning B&W and scanning color for regular silver-based B&W film.

I found the threads, but alas, all of the attachments are gone. 🙁
 
This issue has been raised a fair bit at the Large Format photography forum. What we found with in depth testing was that all scanners have different amounts of noise depending upon the color channel used. For some scanners, scanning in RGB and using the green channel or blue channel resulted in less noise in the image. Scanning in greyscale blends these channels together and does not give you the option.

As well, the optics of the scanner can work better in different wavelengths. I found for example, that on my Minolta Scan Dual IV, scanning in RGB, and selecting the green channel not only gave less noise, but a sharper image as the optics had less aberration in the green.

It is common practise in scanning and printing workshops to NEVER scan in greyscale, but use RGB and pick the best channel.
 
I normally scan in greyscale.

It seems doubtful that I'll need that extra detail, or that my flatbed (canon 8600f) is even capable of anything better than what I'm getting.
 
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