Saving at 300dpi

onguitar
over 11 years ago

 This question might not really belong in this forum but I didn't see a more appropriate place.

I have PhotoImpact 8, a Ulead program.  I know it's old but it does the job for me.  I also have Microsoft Picture It.  Even older.

My problem:  When I create a new image in PhotoImpact the options are to set the image size and the resolution.  I always set the resolution for 300dpi.  When I save it the options are the file type and the choice of no compression, I choose no compression.

In Picture It you set the resolution and compression in the options section.

Last week I uploaded a simple text graphic logo to Vistaprint.  When I viewed it on there it obviously wasn't 300dpi, the resolution was poor.

I thought with those options set that my graphics were being saved at 300dpi.  Why aren't they and how can I fix this?

Thanks for any help,

Mike

Parents
  • 0 over 11 years ago
    Hi Onguitar,
       I can’t specifically answer your question since I have no idea what those programs do.  However,  DPI confusion goes back to prehistoric times.  Wars were fought over it.
       I’ll take a simplistic shot at it.  You will get much better answers from the professionals in this forum.
    1.  The image data within the file does not know anything about dpi and physical size.  Consider an image at 300 dpi and 4” x 6”.  That dpi and size are nowhere to be found on the camera’s CCD.  Neither is it a part of the scene. 
           So what does the file contain.
    2.  It contains rows of pixels.  If you want to know the true resolution of an image for my 12 MPixel camera then the resolution is one pixel out of 4,000 horizontally and one pixel out of 3,000 vertically.  That’s the real resolution.  The data in the file can be visualized as a mosaic of 12 million tiles.  Each tile has a single color.  The picture is created from these pixels (aka tiles) in exactly the same way that a picture can be created from a collection of tiles.
           So what’s with the size descriptions which give dpi and size.
    3.  For starters, it’s Pixels per Inch (PPI) – not DPI – that concerns us.  DPI is left over jargon from offset printing ..
    4.   If I want to print a picture, I have to tell the printer what size I want.  That’s the size of the print.  It’s not the size of anything else.
    5.  Let’s avoid advanced mathematics.  Take an example – my 4,000 x 3,000 pixels shot of the Passaic River.
    6.   Let’s try several sizes
             ---  The wife wants the long dimension to be 36” to fit a picture frame.
             ---  I tell PhotoPaint to make the image 36”. Without so much as asking for my approval, PhotoPaint sets the dpi to 111 dpi.
             ---  Before I can ask what the hell is going on, the wife says she wants a 24” print.  I set in 24” for the width.  Damn. A dpi of 167 pops up. Nobody asked for that dpi.
    7.   One of the grandchildren explains it to me.  The image is 4,000 pixels (aka dots) long.  Divide 4,000 by 36” or 24” and you get the dpi which PhotoPaint offered.
              YOU DON’T HAVE TO ACCEPT THE OFFERED DPI.
        However, in that case you are changing the size in pixels of the file.  That may or may not be what you want.  It’s another ball game.  Most likely, it’s the cause of your problems.  Changing both size and dpi will change the resolution of your image.
    -----------    I NOW LEAVE A BETTER EXPLANAION TO THE PROFESSIONALS.   --------
    Phil 
     
     
Reply Children
No Data

© Corel Corporation. All rights reserved. The content herein is in the form of a personal web log ("Blog") or forum posting. As such, the views expressed in this site are those of the participants and do not necessarily reflect the views of Corel Corporation, or its affiliates and their respective officers, directors, employees and agents. Terms of Use / Privacy​ ​/ ​Cookies / Terms and Conditions / User Guidelines.