Viewing in Photoshop Vs viewing in IrfanView or IE

[hector_evans]

I convert my photos from RAW to JPEG (max size and quality) using Canon Digital

Photo Professional. Photos without noise appear the same in Photoshop CS2 and

IrfanView. However, noisy photos look much better in Photoshop than in

IrfanView. The noise disappears when my viewer is PS in full-screen mode, but I

can see the noise in 100% magnification. IrfanView, IE, etc, show the noise

even at full-screen mode. Why is that?

[colinsouthern]

Possibly because of differing down-sampling and anti-aliasing algorithms.

 

Images are usually much higher resolution than a monitor can display - so photoshop (and other packages) have to remove some of the detail to fit it on the screen. Also, Photoshop has more agressive anti-aliasing (leading to softer but lower noise images) at "odd" viewing percentages (33%, 67% etc) than it does at viewing percentages like 50%, 25%, 12.5 % etc), and that can have a significant effect on how noise is presented.

[rainer_t]

Check these fields:

 

View -> Display options -> Use resample

 

Options -> Properties -> Fullscreen -> Use Resample Function

 

Image -> Resize/Resample -> Size method: Resample + Lanczos filter

 

Restart Irfanview and try again.

[hector_evans]

Thanks Colin and Rainer! Changing my IrfanView settings did work and now viewing with IrfanView is as good as viewing with PS!

 

I was wondering whether the various professional photo printing services apply some kind of similar resampling algorithm for their prints.