1. Reminder: Please use our affiliate links for holiday shopping!

How much can you enlarge JPEG's?

Discussion in 'Printing' started by defektive, Oct 18, 2011.

  1. defektive

    defektive SC Veteran

    375
    May 4, 2011
    Tasmania, Australia
    Sam
    I have an image that was shot in JPEG that I would like to enlarge. I have not enlarged anything since going digital so would like some comments on how far you can push a JPEG before things start getting ugly please.

    Cheers,
    Sam
     
  2. Streetshooter

    Streetshooter Administrator Emeritus

    Jul 12, 2010
    Philly, Pa
    It depends more on the file size then the format of the file.
    What file size do you have? What sensor/camera is the file from?
    I am very comfortable with 11 x 14 paper with a 9 x 1/ image size. This gives me a standard uncropped image. It's my standard size. I've made 16 x 20 & a few 20 x 24's and I am very happy.
    Most online printers prefer jpeg files. So I shoot raw, make a tiff in LR and convert to jpeg for printing.
    Hope this is a start.
    Don
     
  3. bilzmale

    bilzmale Super Moderator Emeritus

    Jul 17, 2010
    Perth, Western Australia
    Bill Shinnick
    If you want to enlarge any image you are using interpolation which means the program 'makes up' the new pixels based on what is nearby. This leads to degradation of the image as you have alluded to.

    Suppose you want to increase the size by 50% from say 4000x3000 pixels to 6000x4500 pixels. The number of pixels goes from 12 million to 27 million - that's a lot of new 'made up' pixels.

    There is a strong belief that it is better to use no more than a 10% increase and to repeat the resizing in 10% bites till you get to the size you want.

    There is software that will resize with minimal quality loss such as onOne's Perfect Resize (previously called something like Genuine Fractals). I have this software and you can probably download a trial.
     
    • Agree Agree x 1
  4. defektive

    defektive SC Veteran

    375
    May 4, 2011
    Tasmania, Australia
    Sam
    Thanks Don. I generally shoot as you do, in RAW then convert to JPEG, but for some reason the camera was set to JPEG when I captured this one. Is there a difference in image quality when you enlarge one that has been shot in JPEG vs one that has been shot in RAW then converted to JPEG?

    In answer to your questions:
    1) File size is 6.30MB, 3615 long, 672 high, resolution 300
    2) Camera used was an M8 set to ISO 640

    Thanks Bill. I am not sure how pixels equate to inches/centimeters but I would like to end up with an image around 36-40 inches on the long side.
    When you talk about resizing in 10% increments does that require special software or can I do that in PSE 9?

    Sam
     
  5. bilzmale

    bilzmale Super Moderator Emeritus

    Jul 17, 2010
    Perth, Western Australia
    Bill Shinnick
    You are looking at a 330% increase in size which is a lot of 10%s. PSE9 will do this OK. The resolution of 300 is pixels/inch so a 40 inch print needs to be 12000 pixels on the long side.
     
  6. Woody112704

    Woody112704 SC Top Veteran

    579
    Nov 7, 2013
    Iowa
    Jared
    Did you end up getting it done Sam? Curious to know how it turned out.
     
  7. Petach

    Petach SC All-Pro

    Oct 22, 2011
    UK, Essex
    Peter Tachauer
    If it helps: As a prolific enlarger.........(I print BIG) I have never seen a discernible loss of quality. I have printed jpeg files of 5mb at up to A1, framed and sold them.

    If printing t home, what does make a difference is HOW you print the files. i.e. make sure your monitor/printer calibrated, use the right inks, use the right paper settings. I use a Canon ix6550 and my experience in printing (I can do A3+) is that I wasted a hell of a lot of ink and paper before I got it off to a T. All printer manufacturers have updated print profiles available for downloading.

    Hope this helps.


    Pete
     
  8. Lawrence A.

    Lawrence A. SC All-Pro

    Nov 8, 2012
    New Mexico
    Larry
    I took a 3 mp file a number of years back, resampled and resharpened and had a 20x24 inch poster made of it that looked quite good. It was a humorous shot, and not gallery quality, but retained a suprising amount of detail.
     
  9. ReD

    ReD SC Hall of Famer

    Mar 27, 2013
    Likewise I have had very acceptable 20x24 prints done off a 3Mp image camera
     
  10. SnapDawg

    SnapDawg Rorschach Test Pilot

    649
    Apr 18, 2014
    Canary Islands
    Ken
    I did a number of A0 and A1 B&W prints from my X10 about two, three years ago. They look just fine, but it took some time in PS to polish the files.
     
  11. ReD

    ReD SC Hall of Famer

    Mar 27, 2013
    A0 sounds good would love to give that a crack - it then depends on the distance viewed at
     
  12. SnapDawg

    SnapDawg Rorschach Test Pilot

    649
    Apr 18, 2014
    Canary Islands
    Ken
    In case of the X10, those files are not exactly made to be printed at sizes beyond A3, if at all - even at base ISO. The 12MP (L mode) are nowhere near ideal 12MP, there are EXR specific artifacts, no proper RAW converters, a lot depends on the structures of your subject and so on. With 4000*3000 pickles on A0 you'd end up at about 85dpi or 3.5 dots/mm and I'd say 2 feet would be the minimum viewing distance but I spent some time experimenting with those files, used different masking, sharpening and upsizing techniques, did a number of small sample prints until I got what I wanted - huge jpgs and the prints. Anyway, I had lots of fun, a great print service and it's not that expensive.