View Full Version : New article by Scott Rosenberg: Scanning B&W on the Microtek 1800F

QT Luong
22-Jan-2006, 22:12
A new article by Scott Rosenberg has been posted,
Scanning Black and White negative film with the Microtek Artixscan 1800F (/1800F-bw.html). Please feel free to leave any contructive comments in this thread.

Kirk Gittings
22-Jan-2006, 22:59
Interesting about scanning as a positive. I will have to test that out. Definitely on mine the Green channel is superior.

Aaron van de Sande
23-Jan-2006, 05:01
It is not suprising at all. The only thing the sensors can do is scan as a color 'positive', it then post processes the information in the scanner to a negative. As you can imagine the scanner is not going to do as good a job converting it to a negative as you will in photoshop. The scanner postprocessing is based on a bunch of assumptions that may not fit what you are doing.

Michael Mutmansky
23-Jan-2006, 07:39
Nice article, and a good help to explain what you can expect for this scanner.

This is comparable to the testing that I advocate each person do with their scanner before getting into real image scanning. This type of testing is critical to ensure that the best results are achieved with whatever device you use. While a particular channel and method may be the best on one person's machine, I believe manfacturing tolerances will probably cause other channels to perform best on the same model machine owned by another. The better quality machines like the 1800f may have enough manufacturing consistancy that they consistantly end up being the green channel, but I'm sure the less expensive scanners will jump about a bit.

I noticed that with the consumer scanners, scanning in positive mode may produce a tonally very different image than scanning in negative mode. I believe it has to do with the sequence in which the scanner software applies the film curve adjustment and then makes the pos-neg inversion. It's easy to see the differences when scanning a steptablet, but should be apparent in any full range image as well.


David Luttmann
23-Jan-2006, 09:14
No surprises here. I've been shooting with Astia and coverting to B&W for a long time as I can get lower noise and sharper detail than from B&W neg film.

Didn't Paul Butzi do a test like this a while back looking into the different channels in a color scan?

Kirk Gittings
23-Jan-2006, 10:46
"The only thing the sensors can do is scan as a color 'positive', it then post processes the information in the scanner to a negative."

Totally logical.

Michael Mutmansky
23-Jan-2006, 11:05
"The only thing the sensors can do is scan as a color 'positive', it then post processes the information in the scanner to a negative."

Totally logical.

Yes, but the sensors don't know anything about what they 'see'. They receive a light stimulus and output a signal. That's it. I don't believe there is any inherent reason that the simple mathematics of reversing the signal produces any image decline.

I think the far bigger reason is that a chrome is the final result, and in the case of both color and B&W negatives, there is a substantial amount of tonal adjustment that happens in the printing process (with traditional printing) that the scanner simply does not do, as it generally is intended to attempt to faithfully reproduce the density and color of a chrome original.

What I'm saying is that a good bit of programming goes into making a scan of a slide look like the original in some fashion, but those same adjustments do not apply to negative film at all.


Michael Mutmansky
23-Jan-2006, 11:21
I got sidetracked and didn't finish my point...

Moreover, negative film is not the final product. That tonal interpretation is designed into the traditionally processed system. Rarely does a person print the full range of density in a negative. It looks flat and somewhat uninspiring most of the time. If you scan a negative and treat it like a slide, the tonality will not be the same as a traditional print without some considerable manipulation of the image in PS or in the scanner software. That's exactly what needs to be done normally to get a pleasing looking print out of a B&W scan.


Sharper scans from slide film? That's a first. I can understand the impression of lower noise (it's called grain), but the die clouds in slide film just don't seem to result in a sharper scan for me. I've got some images here that I can do a direct comparison with and see if this holds true for my scanning methods. Still, slide film acts like a tonal sledge hammer compared to a properly exposed and processed piece of B&W, so I can't imagine choosing to go that route myself even if it does have a slight edge on sharpness.


David Luttmann
23-Jan-2006, 11:24
Actually Micheal,

This mainly has to do with how scanners respond and focus different colors. You see quite often that different scanners have different amounts of noise depending on the channel chosen. Tonality has little to nothing to do with the differences we are seeing in this example. It has become quite common to scan B&W negs as a color positive and then select the channel with the best resolution and sharpness. You'll see this mentioned a great deal in photo.net as well.


Michael Mutmansky
23-Jan-2006, 11:40

I perfectly understand that. Believe me, I understand that very well, and can show you graphs that confirm both the higher noise levels in differnt channels, as well as the differing performance capabilities of different channels. Even my drum scanner shows higher noise in the red channel, but it appears to be of equal sharpness with the other channels.

My point is that slide film has complete tonal rejection on both ends of the scale and is limited to at most 5 stops in the middle, and much less if you look at the linear portion of the film. Negative films have much, much greater latitude, and remain linear as well through a majority of the scale that it can reproduce. Negative films are subject to a similar tonal rejection at the bottom as slide film is, but there is no fixed shoulder at the top.

It means that with slide film as your source, you are locked in to a fairly specific possible intrepretation of the image, but you have more flexability with negative films. That's why I would not take that approach in general. Not that it doesn't work, but I would prefer more control of the image myself, rather than leaving it to the film to decide.


Kirk Gittings
23-Jan-2006, 11:42
"It has become quite common to scan B&W negs as a color positive and then select the channel with the best resolution and sharpness. "

This very point Michael has made many times in this forum and in his writings, but I don't think that is what he is asking you. He is asking why shoot chromes when the final product is b&W, I think.

David Luttmann
23-Jan-2006, 12:29
Yes, my bad. I did misread. I understand where you're coming from, Michael.

Scott Schroeder
23-Jan-2006, 19:29
I don't think I saw it mentioned but what film and developer did you use for your tests?
Would a stained negative such as Pyro yield different results?

23-Jan-2006, 20:22
Has anyone here tried shooting B&W film and having it developed as a postitive (and then scanning the 'chrome') ? I haven't tried this myself but I'm thinking about it.

The processing is done here http://www.dr5.com/main.html, and has been written up in Photo Techniques in 2002, and in a recent issue of Shutterbug.

Steve J Murray
24-Jan-2006, 08:12
Just a note: I just checked the channels on a scan of a 4x5 chrome from my Epson 2450. The blue channel is definitely the sharpest one. I haven't tried scanning a black and white neg as a color positive yet.

steve marino
26-Jan-2006, 00:29
Thanks for taking the time to do this properly. It confirms what I first found when I started scanning in b&w negs on my Nikon Coolscan. However, I found the results (mine) misleading. Yes, there is more information in the image if it is scanned in as color , but this is not necessarily a good thing. My scans that were scanned in this way looked and printed like a desaturated color neg. Not at all what I was after. Why shoot in true b&w if I end up w/ that look? In order for the image to look like a proper b&w shot, I now scan in the neg as a mono neg. This still gives me the use of the color channels in Photoshop (since it is RGB and not greyscale), and the image now looks nice and contrasty like a proper b&w shot. To me, scanning b&w negs in as color gives me a C41 b&w image, and by scanning in as mono, even though there is less information in the file, I get an image that duplicates my 4x6 wet proofs of HP5 or Tri-X. It's like printing in Black Only on my Epson printer compared to printing the same b&w image on my HP printer using all the color inks. The HP print has more tonal range, but the Epson print blows it away. It just makes for a more powerful image.

7-Jan-2009, 10:12
I would believe that in principle.

Comming from the world of digital - I shoot everything in RAW then convert using Gradient Map (Kevin Kubota's settings) for Black & White in Photoshop.

As I venture into LF with my 5x7 Korona, I might be inclined to shoot with the "best" film, color neg/pos or B&W, then convert in Photoshop.