Help with dpi!

[raymay]

I've recently bought the Rebel XT as my first foray into the DSLR world, with hopes of eventually going pro and getting the 5D.
From my understanding, to sell images for print, they must be 300 dpi. However, when I download the images shot at the highest res. to Photoshop, they're all 72 dpi. So... I know this has something to do with my computer screen res... but I can't figure it out?
Any insight from the experienced ones will be much appreciated... Thanks.

[timmciglobal]

DPI means nothing in image tag.

You have X pixels long and Y pixels wide. The "DPI" determines what file size in inches the file will show as.

Canon likes making people feel good so they set it at 72 so you see "wow 48X36 inches" but it has no meaning at all.

Your image is 8 megapixels. That's it. Setting it at 1 DPI would mean a 3500X2300 inch print, setting it at 300 would mean a 10X7 or so print. Nothing has changed, the file is still the file.

Tim

[coldrain]

Forget about dots per inch. And Canon does not want you to feel good, they just fill in a value that is the old standard for computerscreens.

All you have to know is how many pixels wide and high the photos are, you can print them in any size you want. And so can other people. No matter what the "DPI" value says.

DPI used to be valuable for printers that actually really worked with black and white dots per inch. Now old rules and new technologies clash, and you hear the strangest claims about DPI, PPI and what not.

So, in short, ignore the DPI value in the EXIF data. And just print the photos however big or small you want to print them.

[Paul79UF]

If you want to change the DPI value of the image file, go into photoshop, pull up the image size dialog box and change 72 to 300dpi.

But yah, I don't even think about DPI when I do print the very very rare physical photograph. I like to keep everything in the digital world. :)