KCSteve
~ Elite 1000 Member ~
'Resize' makes the image a different number of pixels. Changing from say, 800x400 down to 400x200
'Compress' makes the image take up less disk space with the 'same' number of pixels. I say 'same' because it throws away more actual information on the assumption that what it makes up when it displays the image will be close enough to the original for folks not to notice. The .jpg format is a lossy compression method that relies on the fact that the human eye isn't that good at noticing certain types of distortions, allowing the computer to through away some information and just make up something close enough later.
I generally size pictures to about 600x400 and keep the compression pretty minimal. If your software lets you, you can experiment and see the sometimes dramatic difference in file size between settings like 95 and 93 - it's up near the 'keep everything' level that you get the biggest differences. Once you drop down to around 85 you don't save much more space but the effects start getting pretty visible. Or, if you software uses labels, 'Very High' vs 'High' will make much more difference in space than the 'High' vs 'Medium'
'Compress' makes the image take up less disk space with the 'same' number of pixels. I say 'same' because it throws away more actual information on the assumption that what it makes up when it displays the image will be close enough to the original for folks not to notice. The .jpg format is a lossy compression method that relies on the fact that the human eye isn't that good at noticing certain types of distortions, allowing the computer to through away some information and just make up something close enough later.
I generally size pictures to about 600x400 and keep the compression pretty minimal. If your software lets you, you can experiment and see the sometimes dramatic difference in file size between settings like 95 and 93 - it's up near the 'keep everything' level that you get the biggest differences. Once you drop down to around 85 you don't save much more space but the effects start getting pretty visible. Or, if you software uses labels, 'Very High' vs 'High' will make much more difference in space than the 'High' vs 'Medium'
