PPI

[daniell]

I notice that when I photos off my 300D are 96PPI, is this very important for when I go to print them?

If I go image size, and change it to a higher number, what actually happens? Does it just strech what I have?

[tim]

This has been covered quite a few times, but I can't find anything with search. Google might help.

DPI is only important when you print. Go to resize image in PS CS, turn off resample image, and enter the size of the print you want to do. It'll tell you the PPI (aka DPI dots per inch).

Conventional wisdom says 300dpi makes for a very high quality print, 200dpi is ok, and 100 isn't so hot. I printed a photo at 100dpi from my 300D, 80cm across, and it looks fantastic unless you get closer than 1m away from it. It was interpolated to 200dpi before printing.

[Bodog]

Daniell, PPI, or pixels per inch is just the size of the pixels in your image relative to the size of the print size of your image. Larger pixels equals less pixels per inch, equals a larger print. Smaller pixel size equals more pixels per inch, equals a smaller print. As long as the "resample" box is unchecked you can change the ppi to whatever you need and your image will not be changed or degraded The pixel size really isn't changed, it is just an instruction for your print driver. Generally speaking 300 ppi is considered the sweet spot for printing. An uncropped drebel image at 300 ppi will give you a very finely detailed 10.24 X 6.8 inch print. Depending on your printer, you can print anywhere between 150 and 300 and still get good prints. 150 ppi will print the same drebel image at approximately 13" X 19". Of course the 13 X 19 print will be a little coarser. Hope this helps... :D

[daniell]

Are you guys sure PPI and DPI can be used interchangably?

Unless each dot a printer prints is equal to one pixel, I don't think so.

[PacAce]

Are you guys sure PPI and DPI can be used interchangably?

Unless each dot a printer prints is equal to one pixel, I don't think so.
When used in reference to images files, PPI and DPI can and are used interchangeably. However you are right that they can't be used interchangeably when referring to an image once it is sent to a printer. The PPI of the image is converted to DPI when it gets to the printer so that the image can be printed. An image may be set to 300 PPI. However, all current photo printers have dot resolutions greater than that, such as 2440 dpi, for example. So the printer has to convert the image from 300 PPI to 2440 DPI but that's all internal to the printer.

[elkootcho]

http://www.tildefrugal.net/photo/dpi.php

[kawter2]

my 20D is better than yours it shoots at a native 2336 DPI/PPI


ROCK ON!!! ;) ;) ;)

[Bodog]

my 20D is better than yours it shoots at a native 2336 DPI/PPI


ROCK ON!!! ;) ;) ;)
Lets see, the 20d file size is 3504 X 2336; 2336 ppi will give you a 1 X 1.5 inch print... I'm impressed! :D

[kawter2]

Lets see, the 20d file size is 3504 X 2336; 2336 ppi will give you a 1 X 1.5 inch print... I'm impressed! :D


But i thought the more mega pixels.... whaaaaaa!!!!!


hehe