Page 1 of 3 123 LastLast
Results 1 to 10 of 24

Thread: First drum scans

  1. #1
    Abuser of God's Sunlight
    Join Date
    Aug 2004
    Location
    brooklyn, nyc
    Posts
    5,775

    First drum scans

    I'm getting ready to do the final prints on my first serious color project. The negatives are 2-1/4, and with wishful thinking I scanned them on my home flatbed, which does an incredible job on large format black and white.

    But with medium format color, the quality is only good enough for work prints, promo stuff, and the web. So I spent a bunch of my grant money on drum scans, which means doing all the photoshop heavy lifting all over again. Big drag.

    Before I get going, I want to throw out a question about these scans. The color looks extremely saturated. This in spite of the film being color negative portrait film (mostly fuji 160) shot with an ancient single coated hasselblad lens. My own scans (done with vuescan) have the more muted look that I'd expect. Is it possible that the scanner operator boosted the saturation? Is this a normal thing to do?

    I'm going to want to desaturate the scans a bit, and since I've never dealt with that before, I'm not sure what the best tool is for the job. The hue/saturation panel is the obvious tool ... is it the recommended one?

    Thanks!

  2. #2
    Resident Heretic Bruce Watson's Avatar
    Join Date
    Sep 2003
    Location
    USA, North Carolina
    Posts
    3,285

    Re: First drum scans

    Quote Originally Posted by paulr View Post
    The color looks extremely saturated. This in spite of the film being color negative portrait film (mostly fuji 160) shot with an ancient single coated hasselblad lens. My own scans (done with vuescan) have the more muted look that I'd expect. Is it possible that the scanner operator boosted the saturation? Is this a normal thing to do?
    Is it possible? Depends on the software. Some software perhaps has controls for this. Some (most?) does not. Is it a normal thing to do? I would say no. At least this drum scanner operator has never done it, or been asked to do it. What's normal is to try to get everything one can off the film.

    What you are seeing is most likely the additional clarity you get from a good drum scan using a good solid fluid mount on a drum. A consumer flatbed scan often looks somewhat veiled in comparison. This is normal.

    Another possibility comes to mind. That is, that the film in question had a restricted density range (yes, I'm guessing here ;-). Say for example, it was made at dusk on a very overcast day. The scene maybe metered just a couple of stops of SBR. What a scanner will do with this is to take the restricted density range and spread it across the entirety of the scanner's digital range. This can have the visual effect of "decompressing" a small SBR scene into a full range image. You can get this effect because most drum scanners have the software set the range on the log amp circuits, so the scanner really does scan just the density range the operator specifies for each channel when he/she sets black and white points. I've never seen a consumer flatbed have this capability which may be why you don't see this with your home scans.

    Tell us more: What film? What's the scene like (post it so we can see maybe)? Exposure? Processing? What kind of scan did you specify? How many bits/channel? And what's your working space?

    Quote Originally Posted by paulr View Post
    I'm going to want to desaturate the scans a bit, and since I've never dealt with that before, I'm not sure what the best tool is for the job. The hue/saturation panel is the obvious tool ... is it the recommended one?
    That's the tool I use for that duty, so yes. There is a master desaturation, and you can also desaturate the individual colors individually. Using the master is similar in some ways to using a perceptual rendering intent. Desaturating the colors individually is similar in some ways to using the relative colorimetric rendering intent.

    Bruce Watson

  3. #3
    Abuser of God's Sunlight
    Join Date
    Aug 2004
    Location
    brooklyn, nyc
    Posts
    5,775

    Re: First drum scans

    Thanks Bruce,

    here are a couple of examples (flatbed scans and corresponding drum scans).
    I've done work on the flatbed scans, but have not messed reduced the color saturation in any way. The drum scans are untouched except for conversion to sRGB to match the profile of the others.

  4. #4

    Join Date
    Apr 2001
    Location
    Culver City
    Posts
    169

    Re: First drum scans

    What was the original ICC color profile in the scans?

    Did you do a "Convert to profile..." or "Assign profile..." to put the images in sRGB?
    Last edited by Michael Chmilar; 10-Nov-2008 at 17:31. Reason: typo

  5. #5
    Abuser of God's Sunlight
    Join Date
    Aug 2004
    Location
    brooklyn, nyc
    Posts
    5,775

    Re: First drum scans

    Original for both was adobe rgb, which is my working profile. I used convert to profile, which changes pixel data but attempts to maintain the appearance. There was no significant visible change when I did this.

  6. #6

    Re: First drum scans

    Paul, there is no real way to utilize profiling when scanning color negs. Basically a space is simply assigned, and if the scanner software will allow previewing how that will look in the end, the rest is up to software color controls and the operator. I have seen a fair number of over saturated color neg scans for this reason...
    So if color is not as desired when opening in PS and viewed in a color managed situation, you're left with editing in PS, as you mention. There is no reason to hesitate doing so...
    Tyler

  7. #7
    Resident Heretic Bruce Watson's Avatar
    Join Date
    Sep 2003
    Location
    USA, North Carolina
    Posts
    3,285

    Re: First drum scans

    Looking at your examples, I'm thinking it's probably a little of everything. Some comes from the drum scanner lifting a few veils, some is from some image expansion due to the way the software can set the hardware parameters for scanning, some from the lower density ranges on most negatives compared to the density ranges of trannies.

    And what Tyler is saying too -- can't ICC profile a scanner for negatives. A drum scanner usually works in its own internal working space (most drum scanners were designed and built before the Adobe RGB 1998 working space was invented). It hands the file to you raw without a working space assigned (generally, but some software may allow the assignment of a working space). You open the file in your photo editor of choice and either assign a working space or convert it to a working space. Like any raw capture it's going to need some editing to be "right" however you define that.

    Bottom line is that these scans look to me to be pretty reasonable for raw scans. You think they are too saturated; we all must defer to your expertise as the artist. Edit to suit. I've found hue and saturation changes are pretty forgiving in Photoshop. That is, you can be pretty severe without creating much in the way of artifacts. So be as bold as your vision and good luck with your current project.

    Bruce Watson

  8. #8
    Abuser of God's Sunlight
    Join Date
    Aug 2004
    Location
    brooklyn, nyc
    Posts
    5,775

    Re: First drum scans

    Cool, thanks everyone for the feedback.
    I just wanted to run this by people with more experience dealing with color negs rather than risking repeating a mistake 20 times on 20 negs.
    I'll just procede as normal and desaturate a bit.

  9. #9

    Join Date
    Apr 2005
    Location
    New York City
    Posts
    412

    Re: First drum scans

    That was a very interesting discussion. I work in color neg as well and I now know stuff that I did not know before. Thanks to all.

  10. #10

    Join Date
    Apr 2001
    Location
    Culver City
    Posts
    169

    Re: First drum scans

    It sounds like assigning a profile to a neg scan is rather arbitrary.

    If that is the case, you might try using "Assign Profile..." on the original data to assign something other than AdobeRGB, and see if you prefer the result to assigning AdobeRGB. For example, performing "Assign Profile..." to sRGB, instead of "Convert to Profile..." might get you closer to what you want. (Then again, it could also take you farther away....)

Similar Threads

  1. Purchase drum Scanner or pay for scans
    By Dave Jeffery in forum Digital Hardware
    Replies: 50
    Last Post: 31-Dec-2007, 16:53
  2. Drum Scans - What to order?
    By Ben Diss in forum Digital Hardware
    Replies: 23
    Last Post: 31-Oct-2006, 16:12
  3. Grain in Drum Scans
    By Saulius in forum Digital Processing
    Replies: 7
    Last Post: 13-Feb-2006, 17:44
  4. A&I Labs - drum scans
    By Paul Butler in forum Digital Hardware
    Replies: 7
    Last Post: 2-Jul-2005, 07:51
  5. LF drum scans in Canada
    By tim atherton in forum Digital Hardware
    Replies: 1
    Last Post: 2-Feb-2002, 23:08

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •