72 dpi jpeg --> 300 dpi tiff

Discussion in 'Photoshop' started by Cine, Mar 12, 2005.

  1. Cine

    Cine Guest

    Hi gang,

    I just got a digital camera (Sony DSC-P100) and I've discovered that I
    can't adjust the dpi -- it only takes photos in 72 dpi. I'm a writer
    with a book coming out in May and I need to use the camera to take some
    photos for the book. My publisher wants 300 dpi tiff files.

    The camera is a 5.1 megapixel so it takes fairly large images (2592 x
    1944 pixels) but when I try to adjust the dpi in the "Image Size"
    pulldown in Photoshop, it just ups the width x height pixel ratio too.
    What I want to do is squash the pixels down to 300 dpi.

    How do you do this?

    Thanks,

    Cinefreak
     
    Cine, Mar 12, 2005
    #1
    1. Advertisements

  2. Cine

    PH Guest

    I do not understand why the pull down menu does not give you
    the option to change the resolution......mine does. PS 6,
    and always been like that. Is yours greyed out?

    Anyways. I take it that book is going to be done in XPress
    or Indesign. Not sure if you are doing the lay out or your
    printer. I guess the printing office. In that case just send
    them the raw material and do not worry about the resolution.
    They will solve it.
     
    PH, Mar 12, 2005
    #2
    1. Advertisements

  3. Cine

    RSD99 Guest

    JPEG usually does not have the ability to internally set or record the
    image's resolution (DPI). JPEG is also a destructive compression algorithm.
    For these reasons, people in the publishing industry often do **not** want
    this type of image file(s).

    To fix both of the above problems, convert the graphic to the Tagged Image
    File Format (TIFF), and use something like LZW compression if you really
    need to compress the image. MOST publishers will probably want the image in
    the uncompressed form, and quite possibly also want it converted to the
    CYMK color space. If at all possible, leave converting the image from RGB
    to CYMK to the publisher / printer ... there are soooooo many ways of doing
    that, that it's easy to come up with something that looks horrible.

    (1) Use PhotoShop to resave the graphic as a TIF file;

    (2) Using the 'Image/Image Size' dialog box, change the resolution to 300
    dpi;

    (3) Resave the image with the new resolution;

    (4) If necessary, and again using the 'Image / Image Size' dialog box,
    resize the image to your final size.

    (5) Resave it using the 'File / Save As' dialog box, and use a new name.
     
    RSD99, Mar 12, 2005
    #3
  4. Cine

    Scruff Guest

    Not my info but you mat find it usefull;

    How to convert a photo to print high quality in a four color process.


    What you need to do to convert a jpg into a Tiff. Assuming you have Adobe
    Photoshop, you simply need to do the following.

    1) Open (or launch) the photo in Photoshop.
    2) Go to the Menu - select Image - Mode - then CMYK (which by the way stands
    for Cyan, Magenta, Yellow, Black - the four process colors)
    3) Go to Image - Image Size - And click on the Resample Image Box (lower
    left) so NO checkmark appears. Right above, you will see three boxes that
    will allow you to type in information... they say Width: Height: &
    Resolution. Change the resolution from 72 to 300. Please note that the
    original measurements will change in the Width: and Height: Boxes to a
    smaller size. NOTE: Steve's original (72 Resolution) images are usually
    sized at 34.222" x 22.889" and will re-size down to 8.213" x 5.493" when
    rez-ed up to 300 Resolution. Please make sure you have correctly UNchecked
    the Resample Image Box in this step at the beginning. Now close the Image
    size box by clicking OK in upper right corner.

    4) If you have no sense of color - and like what you see - Select File at
    the top left of the menu and drag down to Save As. Then select where you
    want to save the photo. Give it a name and then toggle the Format Box down
    to TIF. Click the Save Button in the lower right. A new Tiff Options window
    will pop up asking you if you want to save this tiff for the inferior IBM PC
    format or the most excellent Macintosh format. Your choice here - depending
    what you are driving. Leave the LZW compression unchecked. Then click Ok

    This photo is now ready to print in any magazine, brochure or catalog.

    BUT WAIT.... You might want to do a little color correction before closing
    this beast.

    I can't tell you all the secrets because this is where I make the big bucks.
    But here are a few tips...
    1) In the Tools panel there is a little tool that looks like an Eye
    Dropper... select that and place it over some of the contrasty parts of the
    photograph. Make sure the color information palette is open so you can read
    the color values (Menu - Windows - Show Info).
    2) Pick what you think should be the whitest part of the photo. Wave the
    little Eye Dropper over it and look at the Info Palette. The whitest area
    should always have at least 2-3 points Cyan... maybe 1-2 points Magenta. 0-1
    yellow, 0-1 black... Now remember... that's the WHITEST Point.

    I find the best and quickest tool for quick color correction is the
    Selective Color Palette (Menu - Image - Adjust - Selective Color). At the
    top of the box you can toggle the Color Box to select the color you want to
    tweak (Red, Yellow, Green, Blues, White, Natural, Black). Select the color
    you want to change. Remember, always start by checking the color values of
    the area of the photo you want to change first by using the Eye Dropper and
    referring to the Info Palette. You can color correct a photo quite a bit
    with this tool. For some reason with digital... the Yellow always creeps up
    into the blues... so make sure to pull the yellow Waaaaay down to about 7-12
    points.

    Color is definitely in the eye of the beholder... and the printer... and the
    press... and the paper.... but a little tweaking in Photoshop can definitely
    help improve any photo improve on color.

    Okay... two more tips:
    The brightness/contrast tool is good for brightening up those dark photos
    (Menu - Image - Adjust - Brightness/Contrast).
    Sharpening: I find using the Unsharp Mask tool works best. (Menu - Filter -
    Sharpen - Unsharp Mask) Once open you will find three sliding scales to
    adjust... Amount: Radius: and Threshold: Set the Threshold at 0 (zero). set
    the Radius at 1.0. You can then adjust the amount to the necesssary focus
    amount. About 64 to 90 on the Amount seems to do the trick to make them
    crystal clear.

    Okay... I hope that gets some of you novices enough knowledge to get a
    raise.

    I know I am going to hear a ton of different opinions on how to adjust color
    from the rest of you pros... but remember... Opinions are like Digital
    Cameras... everyone has one.
     
    Scruff, Mar 12, 2005
    #4
  5. Cine

    RSD99 Guest

    "Scruff" posted:
    "...
    2) Go to the Menu - select Image - Mode - then CMYK (which by the way
    stands
    for Cyan, Magenta, Yellow, Black - the four process colors)
    ...."

    And ... promptly screw up the image and guarantee poor reproduction in the
    final printed book. Doing a good job of converting an RGB file to CMYK is
    not quite as simple as the information you have quoted would lead you to
    believe.

    PhotoShop's "default" color settings usually result in a rather poor
    conversion. As a minimum ... you should probably have noted that the user
    should *definitely* consult "the printer" (not "the publisher" ... but the
    person who will actually be *printing* the book) to find out what
    conversion parameters work best on his setup. Further, in order for the OP
    to have the full set of tools to do the job, you could have referred him to
    the 'Applied Color Theory' group on Yahoo, hosted by Dan Margulis at
    Ledet.com

    http://www.ledet.com/margulis/articles.html
    http://www.ledet.com/margulis/ACT_postings/ACT.htm

    Another option, would have been informing the OP as to how to join the
    'Applied Color Theory' mailing list ... as follows: Go to the Yahoo! Groups
    site by clicking on this link:


    http://groups.yahoo.com/i?i=GPPzL803nnMa7OZIbwDxAjAiZRM&e=
    t

    (If clicking doesn't work, "Cut" and "Paste" the line above into your Web
    browser's address bar.)
     
    RSD99, Mar 12, 2005
    #5
  6. Cine

    J. A. Mc. Guest

    Amended procedure:

    Using the 'Image/Image Size' dialog box, change the resolution to 300 dpi;
    and UNCHECK the "resample/resize" box !!!!

    Resave the image using the 'File / Save As' dialog box, and use a new name,
    with the new resolution and in the desired format (TIFF);
     
    J. A. Mc., Mar 12, 2005
    #6
  7. Cine

    edjh Guest

    Uncheck Resample in the Image Size dialog.
     
    edjh, Mar 12, 2005
    #7
  8. Cine

    RSD99 Guest

    Thanks for that correction / addition.


     
    RSD99, Mar 12, 2005
    #8
  9. Image>Image Size>Uncheck Resample Image at bottom> type 300 in Resolution
    box.

    File> Save As> Choose Tiff in pull down menu> Navigate to location you want
    to save it> Click Save.


    Steve

    --- faith \'fath\ n : firm belief in something for which there is no proof.
    Webster's Dictionary
     
    Monty Jake Monty, Mar 13, 2005
    #9
  10. Cine

    Scruff Guest

    I found all that on a professional photographers web site
    http://www.stevebruhn.com/news/ . This guy is one of the most successful,
    premier race photographers out there. His site is directed at magazine
    publishers who then set-up for printers, not that you don't know that!
    I noticed that he said everyone has their own way to do things. Guess that
    was directed at you, lol.
     
    Scruff, Mar 13, 2005
    #10
  11. CF,

    First, think of an image size as only in pixels. Pixels are the foundation
    of an image's size.

    The only time the dpi comes into play is when you want to print it. if the
    cropped image will be printed at 3 inches by 4 inches at 300 dpi, then the
    pixel dimensions need to be 900 px by 1200 px. Simple multiplication and
    division.

    If you go to Image and select Image Size, make sure the resample box is
    unchecked, and change the 72 dpi to 300, then the image size will appear in
    inches ( if that is the measurement selected).

    My suggestion is to take all the pictures at the highest resolution your
    camera will allow, save the image in tif in Photoshop, and send the tif to
    your publisher.

    Do not resave a jpg as jpg, as it degrades the image each time it is saved
    in jpg, due to the lossy compression. Keep your original image file
    unchanged, and save it in tif to "play with it". The tif files do not lose
    quality due to lossy compression when they are resaved.

    You might see if your camera can save directly as tif. The image quality
    will be better, but the image file size will also be larger.

    Good luck,

    Dennis


    Hi gang,

    I just got a digital camera (Sony DSC-P100) and I've discovered that I
    can't adjust the dpi -- it only takes photos in 72 dpi. I'm a writer
    with a book coming out in May and I need to use the camera to take some
    photos for the book. My publisher wants 300 dpi tiff files.

    The camera is a 5.1 megapixel so it takes fairly large images (2592 x
    1944 pixels) but when I try to adjust the dpi in the "Image Size"
    pulldown in Photoshop, it just ups the width x height pixel ratio too.
    What I want to do is squash the pixels down to 300 dpi.

    How do you do this?

    Thanks,

    Cinefreak
     
    Dennis Hughes, Mar 13, 2005
    #11
  12. Not trying to be difficult:

    I've never relly understood the need to UNCHECK that box.

    What are the consequences of not doing so?

    What are the advantages for doing so?

    Sincere questions.

    Any reply gratefully appreciated.
     
    Captain Volume, Mar 31, 2005
    #12
  13. Cine

    Tacit Guest

    In English, "resample image" means "change the number of pixels."

    If you resample an image, this changes the number of pixels--if you
    resample down, it removes pixels, and if you resample up, it adds new
    pixels created out of thin air. Both will degrade the quality of the
    image.

    Now, if you are making an image smaller, it is often a good idea to
    resample the image. However, if you are increasing the size of an image,
    resampling is going to produce an inferior quality image--no way around
    that.
     
    Tacit, Mar 31, 2005
    #13

  14. Thanks
     
    Captain Volume, Mar 31, 2005
    #14
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.