300dpi vs 72dpi - quality.

EdinburghGary

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Gary
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Hello,

Am I right in thinking that if you a view a full size 300 dpi image in windows on a 72dpi monitor, that the quality will always look crap?

What happens exactly, there are not spaces between the pixels, again I am confused :)
 
DPI is a constant source of confusion mainly because people thing it defines quality in some way, it doesn't.

Firstly, most monitors are now 96DPI, esp. LCD ones.

So forget about DPI and consider the following question. If you look at a full size image on your monitor will it look bad? It depends....

Are you looking at it scaled to fit on screen?
If so, it now depends on the s/w doing the scaling. It might just chop out every Nth pixel which is the quickest way but also gives the poorest result. It might do some better scaling which means it will look better but you're still dumping information so some quality will go anyway. The best results are when the image has been scaled by 50%, 33%, 25%, etc. when you're only dropping pixels evenly spaced apart.

Are you looking at it 100% scale so one pixel in the image is one pixel on screen (in which case you'll only be able to see a part of the image)?
In this case you're "pixel peeping" and effectively looking at part of a massive print, maybe 3ft on it's longest side. So the quality won't be wonderful but if you looked again from a sensible viewing distance for a print that size it would once again look fine (assuming it sharp, well exposed, etc. to start with).
 
Then you're looking at a 100% zoom of the shot which is the same as a 3ft print. It won't look razor sharp but should look pretty good. If you stood back a few feet from the screen how does it look then? That will give you a better idea of what it will look like as a print.
 
dpi is only for printers. Monitors are in ppi and use a lot less pixels for the same space(inch for example) to provide a similar quality image.
 
Then you're looking at a 100% zoom of the shot which is the same as a 3ft print. It won't look razor sharp but should look pretty good. If you stood back a few feet from the screen how does it look then? That will give you a better idea of what it will look like as a print.



Looks much better, ta for the tip :)
 
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