72ppi or 96ppi?

Charlotte · 28-10-2007, 12:39

I've always converted my images to jpegs of 96ppi, for the simple reason that this is the resolution of our screens. I know most advice is to use 72ppi, but I've never understood that. Why 72ppi??

So I googled + found this interesting discussion on the matter. What do you think?

PS: Mods, I think the link is harmless, but remove it if you feel the need.

**Markulous** · 28-10-2007, 12:46

Buried in that is the explanation that DPI is totally irrelevant to displayed images which are dependant on the number of pixels.

DPI is purely used with respect to print (as printers will print at certain DPIs, so it becomes relevant)

This has to be the number one point of confusion for everyone, at some time!

Charlotte · 28-10-2007, 12:48

Pay attention Mark, we're talking ppi here, not dpi

i.e. re-sizing for web, not printing

**Markulous** · 28-10-2007, 12:51

Same thing applies

Gary Bagshawe · 28-10-2007, 13:11

It took me a while to get my head around this but ppi dpi, all the same really, To test this I took an image of the same size 1 at 300dpi and another at 72 then printed them A5 side by side, and oh look the one at 72 looked crappy and almost blurred whilst the 1 at 300 dpi was like a razor. on screen however I couldnt tell the difference.

Charlotte · 28-10-2007, 13:12

My question is about re-sizing specifically for the web, and I'm interested in hearing members' thoughts on this issue, whether they choose 72ppi or 96ppi, and why.

Edit: This is in reply to Mark; crossed in the post with Gary's comment.

Gary Bagshawe · 28-10-2007, 13:16

I use 72 dpi for web mainly because many libraries tell you that that is there requirement and if it is above this it will get rejected. and tbh you cant tell the difference between 72 and 96, well I can't. (no jokes about my age thank you im feeling rather sensitive about the subject at the moment after the student spanking incident!!!!)

Charlotte · 28-10-2007, 13:16

Quote:

Originally Posted by Gary Bagshawe

It took me a while to get my head around this but ppi dpi, all the same really ...

It's not the same Gary. ppi = pixels per inch + relates to the size of actual pixels on screen. Dpi is printer-specific + relates to the spacing of pixels on paper, but the size of pixels is not affected.

Charlotte · 28-10-2007, 13:19

Quote:

Originally Posted by Gary Bagshawe

I use 72 dpi for web mainly because many libraries tell you that that is there requirement and if it is above this it will get rejected. and tbh you cant tell the difference between 72 and 96, well I can't.

At last, a pertinent comment

Gary Bagshawe · 28-10-2007, 13:23

Quote:

Originally Posted by Charlotte

It's not the same Gary. ppi = pixels per inch + relates to the size of actual pixels on screen. Dpi is printer-specific + relates to the spacing of pixels on paper, but the size of pixels is not affected.

Ok I know it is not the same obviously, but for the purposes of not confusing anybody (like me) it is.

Charlotte · 28-10-2007, 13:28

Quote:

Originally Posted by Gary Bagshawe

Ok I know it is not the same obviously, but for the purposes of not confusing anybody (like me) it is.

P-E · 28-10-2007, 14:10

I use 'save for web' which defaults to 72 ppi.