Help with aliasing upon rotating
mattmcc
Registered Users Posts: 55 Big grins
I'm designing a business card using photoshop cs3 and attempting to place several of my images on it. I'm running into a problem, however, after rotating the images (making a mini-collage). It's severely aliasing them. Moreover, the anti-alias button at the top while rotating is greyed over and won't let me select it.
What do I do?
Edit: Here's a 'save for web' illustrating the issue. Don't mind the rest of the card- most of the stuff on it is a placeholder:
It's most noticeable in the added stroke around it.
Matt
What do I do?
Edit: Here's a 'save for web' illustrating the issue. Don't mind the rest of the card- most of the stuff on it is a placeholder:
It's most noticeable in the added stroke around it.
Matt
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PS: what tool are you using to rotate? Transform doesn't have an antialiasing control to the best of my knowledge (at least in CS2)
I was using the 'place' command using medium-sized jpegs at 72 dpi, but they were several times bigger than what we needed. I then downsized the jpegs by changing the percentages to make them fit the card, and then added a stroke and dropshadow to the layer created by placing them. To fine-tune the placement I used transform>rotate until I had them where I wanted.
I will try again placing the full-size jpeg.
Matt
Update:
I tried with a fullsize @300 jpeg and it was as jagged upon rotation, so I went back to lightroom and exported the photos as uncompressed tif's at 1200 DPI.
Still just as jagged upon rotation.
As the end result is a small business card, I then tried exporting at 2400 DPI. Still a jagged border.
The image itself looks very good, but it is the border that is anti-aliasing. I've tried adding a border by making the canvas 1% bigger than the image, as well as by using the 'stroke' effect. Both work perfectly were I to keep the images un-rotated, but as soon as I rotate, the aliasing shows up.
Matt
Are you finalizing a lot of rotations per file and thereby maybe destroying the data too much? Probably shouldn't cause it, but could be solved by playing with a smart object version, until you've decided.
Might some related layer styles be involved that have anti-aliasing unchecked?
Should no solution come up, you might look into these:
www.redfieldplugins.com/filterPerfectum.htm
www.powerretouche.com/Antialias_plugin_introduction.htm
Before I spend the money on a plugin, do you know of a better way (ie, how would you do it) To take images, add a border, and rotate them to acheive this effect? It could simply be that my technique is off.
What I currently do is go File>Place. I then select the image I want to add to the business card template, and resize and rotate to fit. If I need to alter the rotation I use transform>rotate.
The overlapping effect is manipulated by layers.
Is this what you would do?
Image showing Photoshop screenshot of full image at 16.7% zoom. Aliasing is horrid because [a] the zoom percentage doesn't translate pixel-for-pixel well (25/50% look better, but not a bunch) and Photoshop's doing a lazy job of downscaling the image to fit on screen in the first place, resulting in more aliasing than could be had at this size.
Image showing Photoshop screenshot of full image at 100% zoom. Notice that while there are still jaggies, their size relative to the size of border is quite small. Printing this image at 3.5x2" would result in the jaggies being roughly 1/250" in size (factoring that about five of the anti-aliasing pixels are easily visible; brighter than 50% in the L channel) which would be far from noticeable and probably beyond the limits of any printing system.
Image showing final, downscaled version of the image at 800px wide, resampled with Photoshop's Bicubic Smoother option. This seems to be about the best the aliasing can get (IMO and from my quick experiments) with only 800x457 pixels to work with. At this point, I think it looks passable on screen, but the full size version would print basically flawlessly.
Keep in mind that at the size of the images that are being posted on Dgrin (~800-1000px wide), there *will* be some noticeable aliasing with high contrast lines at shallow angles no matter what is done to prevent it - there's just not enough pixels to represent artificial smoothness.
Indeed, it was all too easy to replicate your findings, even get them worse just by having rotated one pic 3 or 4 times (rotated twice when the layer style was on it; look how ugly). Moving the stroke pos to "inside" brought partial relief (oops, I see it's a different angle).
This is what a pretty much maxed out PowerRetouche plugin does (I have no experience with the other one). It works reasonably for some of the angles, others are much less satisfactory. Put it in a layer in front of yours to compare.
The borders where done with layer styles. What I would try next is to only add the shadows as layer styles and paste flat pictures with white border added in advance. I'm hopeful that would make a difference at these kinds of sizes.
Cheers!
Matt