SAVING SCANS AND HOW TO RETAIN HIGHEST QUALITY

Discussion in 'Digital Darkroom' started by eye-of-searle, Nov 21, 2005.

  1. I have searched the forums and have not really found an answer to my
    specific question so here it is,

    I just aquired a Nikon Coolscan V and my scans are anywhere from 55
    to 65 MB per scan as Tiffs. How do I save these images and keep
    close to the same file size? If I save as a jpeg, I get a
    drastically reduced file size so that method is out. Max 1 to 2
    MB. When I save as Tiff, I get a file size of about 9 to 10 MB per
    image. Is this right? Is this enough to produce quality 8x10 and
    11x14 prints? Maybe I am missing something so bear with me if this
    is a stupid question. I am new to scanning my own negs and trying
    to learn to right way.

    What is the best process to save scans? Ultimately, they will be
    archived on CD.

    Any help would be much appreciated.
     
  2. TIFF files use lossless compression when saving with LZW compression enabled (which is what you probably did). There's no loss of quality when saving via that method.
     
  3. Scan at 16 bit per channel, use a large color spcae and save immediately as a TIFF

    If you are getting full frame scans out of Coolscan V that create a file size of 55-65 MB
    then you are scanning at 8 bits per channel. Scan at 16 bit per channel instead. What
    colorspace are you scanning into? Adobe RGB (1998) is a better choice than sRGB, better
    still is Ekta Space, PS5. Created by photographer joseph Holmes (
    www.josephholmes.com/profiles.html ) to be just large enough to contain all the possible
    color information that can be recorded on an E6 type or Kodachrome transparency.
    Unfortunately Nikon Scan doesn't offer us the ability to scan directly into a sapce larger
    than Adobe RGB (1998) so you'll have to choose "wide Gamut RGB" (preferences > color
    management > RGB ) and in Photoshop convert that to Ekta Space. (You should really read
    the 18 page PDF Holmes includes in the Ekta Space download to understand the whys of
    this).

    If you are scanning negatives , skip the whole scanner profiling process as you just can't
    profile color negative materials -- just too many variables in the orange masks with
    different color negatives material.
     
  4. jtk

    jtk

    Your tiny 9MB TIFFs may work satisfactorily at your desired sizes with your particular images. Look and see.

    Recently I inadvertantly printed a 7MB file to 12X18", got generally attractive results except for strong jaggies in straight lines, black against white. With the same frame the correct 120MB scan (4000ppi @ 13X19) has no jaggies, is sharply grainy (NPZ 800 color neg)...I might want to re-scan with slight grain reduction, but I wouldn't want to save smaller than 120MB.
     
  5. As Ellis says, you're scanning at 8 bit while the scanner can do 14 bit. My tif files are 135
    megs and those are the files I archive.

    I scale them down to something a lot smaller and save as jpg for presentation after doing
    noise reduction on the original. But the originals are left untouched. Disk space is cheap and
    re-scanning is time consuming.
     
  6. So does that mean it's normal to get file sizes of about 9 to 10 MB from the 55 to 65 MB scans?

    Is this the best wat to save the scans or is there another way that would be better?
     
  7. Also, you probably want to archive to DVD not CD, if you intend to keep the full quality
    output from your scanner. Even then I can't quite fit 36 135m scans on one single layer dvd.
    But blank dvds are under 50 cents now, and my time is worth more than ever scanning a
    negative twice if I don't have to.
     
  8. jtk

    jtk

    Jim, If you were using the full 14bit capacity of the machine (twice what you seem to be using) you'd get 120+MB files. Perhaps you're making a mistake when you save...perhaps you don't mean to size down from 55-65 to 9-10?

    If you don't have a second hard drive, or even a third, you're going to want one. I use two external 120G Maxtors. Extra drives are more immediately important than backing up, since you do still have the original film. I use the third drive as a backup, as well as DVDs.
     
  9. So does that mean it's normal to get file sizes of about 9 to 10 MB from the 55 to 65 MB scans?
    No. something is set wrong. Unless you are cropping like crazy or reducing your ppi to something like 72 but not changing the output size in inches the TIFF should remain at 55 to 65mb.
     
  10. You guys are probably right that I am scanning at 8 bit. I will adjust this tonight when I do some more scans.

    When I go to save, I use "Save As" and I get a choice of several formats. Can't remember exactly from here at work but the system asks me if I want to use compression. I have been saving to tiff with no Compression. Or at least I think I do? Anyway, I will try to suggestions above an see how it works.
     
  11. Ellis, just saw your recent post. I could be getting confused on the 9 to 10 mb size. This may be after some processing in PS. Sorry about that, I'm at work right now and going off last night's memory. I definitely think I am only scanning in 8 bit though and I am sure about the 55 to 65 mb files size from scans. That should be easy to resolve.

    I think the 9 to 10mb sizes are after some cropping in PS. That's an entire different problem I am having. I still need to learn a bit about sizing images for print. Say a 5x 7 or 8x10 from the original file. Cropping vs. resizing. But that's another thread.

    Sorry again for the 9 to 10mb confusion. I just smacked myself on the head for everyone.
     
  12. Ellis, just saw your recent post. I could be getting confused on the 9 to 10 mb size. This may be after some processing in PS. Sorry about that, I'm at work right now and going off last night's memory. I definitely think I am only scanning in 8 bit though and I am sure about the 55 to 65 mb files size from scans. That should be easy to resolve.

    I think the 9 to 10mb sizes are after some cropping in PS. That's an entire different problem I am having. I still need to learn a bit about sizing images for print. Say a 5x 7 or 8x10 from the original file. Cropping vs. resizing. But that's another thread.

    Sorry again for the 9 to 10mb confusion. I just smacked myself on the head for everyone.
     
  13. Look under Scanner Extras for Pixel data size, set it to 14 bits. The resulting output should
    be about 135mb, saved as a tif. I don't get the option to save as Tiff compressed, the
    compressed option is dimmed in the menu.

    It takes a little under 3 minutes per scan with ICE on normal, ROC, GEM & DEE turned off. I
    use Neat Image in Photoshop if I want to reduce / remove grain and noise.
     
  14. ted_marcus|1

    ted_marcus|1 Ted R. Marcus

    When I save as Tiff, I get a file size of about 9 to 10 MB per image.
    That's awfully small for a TIFF. You didn't say what did the saving, the scanner software or your photo editor. But it sounds like you've set it to save for a specific print size, and it's resizing the image.
    To "retain highest quality," your scanner should save its scans as 16-bit TIFF files. Those should be somewhere around 128 megabytes each. Then you can edit the image in Photoshop (or whatever you're using) with limited degradation. You can save significant space on your archival CD (a DVD really would be better for files that size) if you save the scanner's file as a lossless JPEG 2000 right after you load it into Photoshop. That can reduce the file size by up to 40% with no loss of quality. Be sure you explicitly select the lossless option before saving. The PNG format also provides lossless compression, but at least in Photoshop CS2 its compression isn't as good. I find that LZW compression for TIFF files doesn't work at all for 16-bit files.
    If you're not using Photoshop or an editor that can work fully with 16-bit images, you'd be wasting disk space with 16-bit scanner output (although you might want to do it anyway so you won't have to rescan if you do eventually get Photoshop). Adjust the image in the scanner software to get as close as you can to the final result, then save the file as an 8-bit TIFF. I don't know if your scanner software makes its adjustments in 16-bit mode before saving in 8-bit. Vuescan does that; Canon's software for my FS4000US doesn't.
     
  15. jtk

    jtk

    I scan most images @ 4000ppi for 13X19 (my printer's largest size)= 120mb approx, then immediately duplicate each TIFF, edge crop/rotate/perhaps adjust...that'll be slightly smaller due to the edge crop. There will be more post-processing later but the original scan is usually untouched.

    The fastest/cheapest way to gain storage space is to edit (throw away) scans of mediocre images. The best backup is usually the film itself, stored properly.
     
  16. Ted,

    I am using PS 7. Don't have CS2 right now. Not sure if it supports JPEG 2000. But if it does, this might be a good route for me since I am using CD to store right now. I will probably add a DVD-Burner after the first of the year or maybe a new Computer geared more toward imaging.

    John,

    Thanks as always for your help. When you said "edge crop/rotate/perhaps adjust", did you mean post scan in PS or prescan in Nikon Scan or other software?
     
  17. jtk

    jtk

    I don't tinker with the scan process other than selecting a reasonable profile, confirming that I like the focus point, and maybe reducing grain slightly. I happen to use CS2 now but I worked the same way with Elements 2 and 7. I duplicate the original TIFF to another same-size TIFF, do things with TIFF duplicates leaving the original alone.
     
  18. ted_marcus|1

    ted_marcus|1 Ted R. Marcus

    Jim, there is a freeware JPEG2000 plug-in available from fnordware. It's supposed to work with Photoshop 5.5 and later. I downloaded it, but I discovered CS2's native plug-in before I got to try it.
     
  19. OK, here is an update.

    I figured out the 14 bit scanning. Simple fix. Thanks everyone for clearing that up. I am now getting 130+ size scans. I'm now good there.

    Here is what is still confusing the hell out of me. I save as a tiff from Nikon Scan onto my system. I still the same 130+ MB file. This is where I get confused now. Let's take one of my earlier 65mb scans. My image size in PS 7 is 1.49 in by .987 in. at 4000 per inch or 5959 X 3826 pixels. So.....

    1. If I want to make a 8x10 print, what is the best way to go about that? Resize to 8x10 or just crop to 8x10? Either way, the resulting image now has a dpi of 300 and the file size is about 9 MB. Does this seem correct?

    And,

    2. What if I want to edit for contrast, touch up, etc. Is it best to do this to the original 65MB (to be 14bit 135MB file in future)scan and just resize/crop to print when needed? Because when I resize/crop I loose file size, if that matters.

    I just want to be sure I am getting the best file possible to print.

    Sorry again for all these questions, These few areas are killing me. I can't seem to get my head around it. I promise I will stop bothering you guys after this. If I am asking to much, just tell me and I will chill out.

    Jim
     
  20. ted_marcus|1

    ted_marcus|1 Ted R. Marcus

    If I want to make a 8x10 print, what is the best way to go about that? Resize to 8x10 or just crop to 8x10? Either way, the resulting image now has a dpi of 300 and the file size is about 9 MB. Does this seem correct?
    You're resizing the image when you crop it, reducing the number of pixels. Don't. In the crop tool, just enter "8 in" and "10 in" for the dimensions and leave the DPI resolution field blank. That way, you're fixing the aspect ratio of the crop box at 1:1.25 but leaving the actual pixels unchanged. That's what you want to do, "retain highest quality." You can adjust the DPI (but not the actual pixels!) when you make the print. Send the printer driver all the pixels you scanned and let it worry about scaling them properly to the printer's native resolution.
    What if I want to edit for contrast, touch up, etc. Is it best to do this to the original 65MB (to be 14bit 135MB file in future)scan and just resize/crop to print when needed? Because when I resize/crop I loose file size, if that matters.
    Yes, you want to do everything with the full set of pixels the scanner gave you. And when you're done, you want to save all those pixels. You can save disk space by reducing the image 8 bits and saving that (as a PNG or lossless JPEG to save the most space) once you're sure you're done editing. Do this before the final sharpening, since you'll want to sharpen the image differently depending on whether it's for printing or monitor display. Resizing the image (as opposed to merely adjusting the DPI, which doesn't change the actual pixels) throws away data and is likely to reduce the quality of your prints. Printer drivers specialize in converting input pixels to the appropriate resolution that the printer uses internally, so the rule is to feed it as many pixels as you've got.
    The distinction between changing the "resolution" (the dots per inch) and resizing the image by changing the actual pixels is confusing for many people. In general, the "resolution" is completely meaningless, since it's just a number in the header that you can set to anything you want. What matters is the number of pixels. You don't want to change that unless you're reducing a copy of the image for the Web or e-mail, or else you're "ressing-up" a copy of the image to make a large print. The thing to remember is to keep all the pixels that came from your scanner (apart from cropping the image to improve composition). Once you've lost them to resizing you'll never get them back!
     
  21. TED!

    You da man!

    That clears it up nicely. Thanks for giving me an easy to understand explantion to my last questions. Leaving the resolution box empty was the key. Never thought of that.

    Anyway, thanks again for the help, John, Ted, Ellis and others.

    Much Appreciated.

    I am sure I will have other questions along the way.

    Jim
     

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