Printing images,file sizes ?

[paul11]

Hi all,I would like to start printing some of my images but I’m a bit confused about the file size in MB. When I look at an image in zoombrowser ex it shows my jpg images to be about 3.5 MB but when I open them in CS3 they show between 20-30MB.After doing a 100% centre crop of an image and saving it as a tiff it ended up at 10.5MB,Does this mean I can print this file at A4 or even A3 or am I missing something here,,,,,,,,Paul.

[René Damkot]

File size in Mb (of a jpg) has not so much to do with the number of pixels, more with the compression.
For an A4 print you'd need about 2480x3508 pixels.

Worry about pixels, not Mb.

[tim]

File size is irrelevant, pixel dimensions are what's important. Don't bother with TIFFs they're unnecessary and as we've read on a recent thread the size can cause problems for some print labs. You want 300ppi if you can get it, but prints can be made with less pixels depending on the print size and viewing distance.

Just FYI the size in ZoomBrowser is probably the JPG file size, in CS3 it shows the uncompressed size - which may or may not be the same as the size of the TIFF.

There's an FAQ as well, here (http://photography-on-the.net/forum/showthread.php?p=3740438).