The Fallacy of Judging Image Quality Online

[Jay Gould]

Hi, this is an interesting article from Luminous Landscape: http://www.luminous-landscape.com/essays/rant23b.shtml

With the 7D about to be in our hands - I will hold my new toy tomorrow - looking at our images onscreen - I am now viewing everything on a 13" Dell "somewhat calibrated" does become a challenge to keep things into perspective.

[Andy Wai]

The thing about Michael Reichmann is he really likes to stick into his particles totally irrelevant photos from his latest toys. I think the article below from Juza makes the point much better:

http://www.juzaphoto.com/eng/articles/judging_image_quality_photos_web.htm

Andy

[Ed Cordes]

Bottom line for both articles is that web presentation is not the way to judge image sharpness.

[Roman Kurywczak]

OK....I'll bite......speaking from an often calibrated monitor and 20/10 vision.....are they saying when I judge an image that is tack sharp...... presented at these low resolutions it won't be sharp at higher resolutions?.......or are they preaching down from the pulpit to justify unsharp images?......just curious!
Here's my preach......if you can get it sharp at these low resolutions......it should still be sharp at the higher res......if it is presented unsharp at these low resolutions......it should be questioned if they are indeed sharp! If the original is actually sharp....there are 1000's of examples on this website that show it can be done at low res! period.

[Andy Wai]

OK....I'll bite......speaking from an often calibrated monitor and 20/10 vision.....are they saying when I judge an image that is tack sharp...... presented at these low resolutions it won't be sharp at higher resolutions? [...]
Not "won't be" but "not necessarily be". That's my interpretation of Juza at least. By the way, different monitors have different sharpness. My reference monitor is a lot sharper than regular monitors, not just CRT, but LCD as well. I have to take that into account when judging web downsize.


If the original is actually sharp....there are 1000's of examples on this website that show it can be done at low res! period.I think the problem is the other way around. Juza has a rather sophisticated downsize process to preserve impression of sharpness on the way down. On images that are reasonably sharp but not down to pixel level, the process can be overcooked just a hair to mask that last little bit of fuzziness. At web size, there is no way to tell if that has happened. I think that's what Juza's saying. I know Juza's process very well since I use a variation of it myself. This masking can definitely be done in my experience.

Andy