Photoshop aliasing and moire issues

[Brodie Geers]

Opening up a rendering 5000px wide, when I out to see it all on one screen photoshop is introducing serious aliasing all over and moire on the bricks. If I zoom in it quickly goes away or if I save it as a jpg and open it with windows viewer it looks fine. Are there some Photoshop settings to adjust this behavior?

 

-Brodie

[Tommy L]

Its just a display issue, I wouldn't bother doing anything about it.

[Brodie Geers]

Hrm...if I'm seeing dramatic AA and moire, why wouldn't I do something about it?

 

-Brodie

[Brodie Geers]

here are some examples, 1st image is a piece of the image in photoshop when I fit the image to screen. the second image is the same piece of building but this time it's a .jpg opened in windows viewer at full screen.

 

 

 

-Brodie

[Tommy L]

well exactly, so its just a viewing issue. If it doesnt print badly or display incorrectly at screen resolution then its a display problem, not a problem built into the file. So you dont need to do anything about it...unless it really bothers you? CLient will not have the same problem so forget about it.

[Brodie Geers]

Well, mostly it's a just a bother and since all PS is supposed to do is work with images, I presumed there was just an easy setting I was missing. More importantly though, my client is my boss who doesn't really understand (or care to understand) why an image looks kinda screwy. And it's not uncommon for him to be looking over my shoulder while I'm editing.

 

-Brodie

[Crazy Homeless Guy]

The more recent versions of Photoshop (CS4/CS5) seem to be worse at reducing moire patterns than the CS3 and earlier versions. In the early versions every other zoom increment displayed perfectly, in th elater versions it is less consistent in the smoothness of the display at different zoom points. I have always assumed it was partially due to the incorporation of graphics card acceleration, and the more than likely need to revisit the way graphics are diaplyed in order to bring the graphic card acceleration into the way Photoshop functions.

 

It does indeed make it more difficult to edit because it limits the zoom amounts you can view the image at while getting a sense of what the final will look like.

 

I supposed there is a possibility there is a possibility that the moire'ing could now be reduced by tweaking your graphic card display settings, but I am not willing to bet anything worth value on that. I am just guessing at possible solutions.

[Jon Berntsen]

This is actually an interesting topic. I always work on sizes demanding me to zoom out to view the whole composition.

 

My biggest "problem" is that the final image (when saved and opened in windows image viewer or similar) looks shit compared to the crisp nice expression that I was predicted whilst working in photoshop. This IS an issue for me, and I can very well understand why brodie here is annoyed, even if I don't share the same reason.

 

I'm loosing money (or at least not earning as much as I could) because of the need to alter the final image twice or multiple times after finding out how the image actually looked like outside of photoshop. When working in photoshop I'm getting engaged and of course I do changes based on what I see on my (calibrated) screen during the process.

 

Haven't managed to improve my workflow on this yet. I'm not meaning to hi-jack brodies thread, but if anybody have any ideas on how to address this issue, I'm open for suggestions. Thanks.

[mattclinch]

its completely about how photoshop aliases or interpolates some of the cached zoom levels below 100%. by default you have 6 cache levels. you can go as high as 8 levels, which will give you cached views at 66.67, 50, 33.33, 25, 16.67, 12.5, 8.33, and 6.25% these are essentially reduced sizes of you image from 100%. photoshop saves these reduced versions on the fly and the interpolation algorithm PS uses is quick and dirty to speed up the process.

 

you will find there is no problem at viewing at percentages like 10%, 25%, 50% - as at these values the interpolation algorithm can simply interpolate every 10th, 4th or 2nd pixel respectively and the result is fast and clean. but if you view at 16%, 33.33% or 66.66% there are aliasing issues from the interpolation which results in jaggies and bad moire.. not much you can do about it really. does annoy me too.