1. Welcome to Mu-43.com—a friendly Micro 4/3 camera & photography discussion forum!

    If you are thinking of buying a camera or need help with your photos, you will find our forum members full of advice! Click here to join for free!

Preparing files for printing?

Discussion in 'Printing' started by MNm43, Jun 12, 2018.

  1. MNm43

    MNm43 Mu-43 Veteran

    230
    Mar 19, 2014
    I was wondering what folks do to prep their files for printing besides the obvious cropping to the print proportions. I've had hit and miss results on both paper and metal when it comes to producing sharp, detailed images that don't seem to match the screen image. Do you folks resize the image at 300 DPI (so a 5x7 would be a 1500 x 2100)? Do you post sharpen (that is, after you do your usual sharpening of a RAW file for the screen) image before you output the print file? Using LR, do you use the output sharpening as well?

    I'm not talking about color here. The lab I use seems to get the color pretty close to what I expect. It's the detail and sharpness that I'm struggling with. Or are prints just not that inherently sharp compared to screen images . . .?
     
  2. Carbonman

    Carbonman Mu-43 All-Pro Subscribing Member

    Jul 10, 2014
    Vancouver BC
    Graham
    One place I like (an artist's supply store) accepts TIFF files and they alter the DPI as necessary. They will also accept JPEGs but I like to have as much data available as possible.
    The other 2 labs I've used only accept JPEGs (both are camera shops). Their results look good but I wish they would use TIFF too.
     
  3. PacNWMike

    PacNWMike Mu-43 Hall of Famer

    Dec 5, 2014
    Salish Sea
    I print my own and let the printer driver do the math. Not sure why you couldn't let a lab do the same...within reason. Over-sharpen what would be appropriate for screen viewing.
     
  4. ScottinPollock

    ScottinPollock Mu-43 Top Veteran

    Pixels is pixels... (the dpi thing is just metadata). Ideally, you'll have as many as possible, but if you have more than 600 of them per inch, you might want to ask about your lab's printer resolution. For if they are down scaling, their algorithm may not be as good as your software's.

    I have never printed from digital in anything less than 8x10, and with 12-24 megapixel cameras it has not been an issue for me (Apple does most of my prints).

    As for sharpening... that is a bit of an art gleaned from experience. The pixels on screen are far larger than those that will be printed, and scaling in software to sharpen doesn't really show you the end result. My recommendation would be that once you discover your lab's native rez, get a print with a lot of detail at that resolution, make ten prints with ten different levels of sharpness and compare what you get back. Of course if you have less pixels than your lab's native, you have more homework to do as do you print less dots, scale in your software, or let the lab scale it? This is why some folks go through the PITA that is doing their own printing.

    Without any kind of controls to compare, it is always gonna be hit and miss.
     
    • Like Like x 1
  5. MNm43

    MNm43 Mu-43 Veteran

    230
    Mar 19, 2014
    Have you had the same file printed in both TIFF and JPEG? The lab I use only accepts jpegs as far as I can tell.
     
  6. ScottinPollock

    ScottinPollock Mu-43 Top Veteran

    If no manipulation is to be done, you won't see a difference between png, 100% jpg, or tiff. The dots are all there. Tiffs can provide more color info (depending on the converted raw file and export process) but it has nothing to do with resolution.
     
    • Like Like x 1
    • Agree Agree x 1
  7. ex machina

    ex machina Mu-43 All-Pro Subscribing Member

    Jan 3, 2014
    Baltimore, MD
    Yeah, you have to experiment. I tend to bump up sharpness and contrast +10 on output after using LR's soft-proofing to match the printer's profile as close as possible. I also check to make sure I'm in-gamut so there's no clipping of the highlights or blacks.
     
    Last edited: Jun 13, 2018
    • Like Like x 1
  8. Carbonman

    Carbonman Mu-43 All-Pro Subscribing Member

    Jul 10, 2014
    Vancouver BC
    Graham
    No, I haven't. It might be worth a try because I don't typically do a lot of PP to my work.
     
  9. Highlander

    Highlander Mu-43 Veteran

    290
    Mar 17, 2011
    USA, Northeast Coast
    Richard Correale
    jpeg files are compressed and therefor lose resolution. You won't notice it if you're printing at relatively small sizes but if you enlarge to a great degree the difference in resolution will be noticeable between a jpeg and tiff.
     
    • Funny Funny x 1
  10. Highlander

    Highlander Mu-43 Veteran

    290
    Mar 17, 2011
    USA, Northeast Coast
    Richard Correale
    Anything above 300 dpi is overkill and will show no advantage when printed.
     
    • Funny Funny x 1
  11. ex machina

    ex machina Mu-43 All-Pro Subscribing Member

    Jan 3, 2014
    Baltimore, MD
    I don't believe you can tell a difference between a JPG and a TIFF when the JPG is saved out with a quality setting of 100%
     
    • Agree Agree x 3
  12. Highlander

    Highlander Mu-43 Veteran

    290
    Mar 17, 2011
    USA, Northeast Coast
    Richard Correale
    If you print it large enough you can. I've seen it. JPG files are compressed even at 100% quality setting, otherwise there would be no need for the file format.
     
    • Funny Funny x 1
  13. ex machina

    ex machina Mu-43 All-Pro Subscribing Member

    Jan 3, 2014
    Baltimore, MD
    How large is "enough"?

    My understanding is that at 100%, jpg color information is lossy but resolution is unchanged.
     
  14. ScottinPollock

    ScottinPollock Mu-43 Top Veteran

    JPEG compression does not affect resolution, it quantizes the color information of the image and reduces the number of bits necessary to display that color information. It uses algorithms based on how the human eye resolves color. Of course a LOT of compression can cause artifacts (posterization) that are certainly discernable, a 100% JPEG will not.

    Here are PNG screen captures of two exports from DxO PL at 100% JPEG and 8-bit TIFF. Can you tell me which is which on these 1:1 crops? If you can't see the difference at 1:1 on 96 PPI monitor, you'll never see it at 300 or 600 DPI.

    Screen%20Shot%202018-06-13%20at%207.05.27%20AM.
    Screen%20Shot%202018-06-13%20at%207.05.36%20AM.
     
    • Agree Agree x 1
  15. archaeopteryx

    archaeopteryx Mu-43 Veteran

    462
    Feb 25, 2017
    More specifically, jpegs use a YCbCr colorspace that's often subsampled at 4:2:0. This means every pixel has unique Y information (luminance) and Cb and Cr are indicated every other pixel both horizontally and vertically. This is the same basic luminance-chrominance resolution as a Bayer sensor and, at 100% quality, no quantization occurs. So loss is restricted to rounding in the maths underlying jpeg compression and decompression (the DCT-IDCT pair) which, in most implementations, is likely to be infrequent and introduce an error of about 0.2%. Since prints miss the last 1% or so anyways, this is insignificant and using 8 or 16 bit lossless is of no particular importance.

    If one's working with high resolution images or is particularly enamored of demosaicing the jpeg can be encoded 4:4:4, which includes Cb and Cr at every pixel. It doesn't seem to me this is something people check on often but, in general, I'd expect a reasonably well designed photo editors or raw developers to progress from 4:2:0 to 4:4:4 as the requested quality increases. I know GIMP defaults to 4:2:2 (which has twice the chrominance infomration of 4:2:0) and offers an advanced setting for subsampling which allows 4:4:4 as well as some other flavours.

    However, rather than take a moment to actually look, it seems to me it's often assumed losses in lossy codecs must be significant.
     
    • Like Like x 2
    • Informative Informative x 1
  16. Highlander

    Highlander Mu-43 Veteran

    290
    Mar 17, 2011
    USA, Northeast Coast
    Richard Correale
    As I said before, you will need to compare a much greater enlargement in order to note a visual difference. If you're starting out with a raw native capture at 12" x 15" and want to print it 36" x 45" would you rather use the raw file saved as a tif or jpeg @ 100% quality? I know which one I'll be using.
     
    • Funny Funny x 1
  17. ScottinPollock

    ScottinPollock Mu-43 Top Veteran

    You can jump through TIFF hoops if you want to, but consider this...

    A 45" dimension from a M43, 16MP sensor will print at 102 PPI without scaling. If your viewing the two images I posted above on a typical digital monitor, you are most likely seeing them at 96 PPI. Do you see a quality difference on the monitor? Then you won't in the print.

    Even when scaling, the results do not support your theory. The following images were scaled to print @ 222 PPI at 45 inches. The one on the left was exported by DxO to JPEG, and then scaled via bicubic in AP and re-exported to JPEG. The middle was exported by DxO to JPEG with bicubic scaling. The right was exported to TIFF by DxO, then scaled bicubic and re-exported to TIFF in AP.

    Screen%20Shot%202018-06-13%20at%209.59.06%20AM.
     
  18. Highlander

    Highlander Mu-43 Veteran

    290
    Mar 17, 2011
    USA, Northeast Coast
    Richard Correale
    And what's the size in MB of each of the three files?
     
    • Funny Funny x 1
  19. ScottinPollock

    ScottinPollock Mu-43 Top Veteran

    The TIFF is huge and the JPEGs are tiny (about 10:1).
     
    • Agree Agree x 1
  20. Highlander

    Highlander Mu-43 Veteran

    290
    Mar 17, 2011
    USA, Northeast Coast
    Richard Correale
    And why is that?
     
    • Funny Funny x 1
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.