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Posted on 17/06/10 11:23:22 AM |
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tooquilos
Wizard of Oz Posts: 2920 Reply  |
New Layer via Cut
Each time I create a new layer via cut I end up with a very fine white line. Is there anyway of overcoming this? Tried various things already by modifying/refining the edges but to no avail. Here is a screenshot of what I mean.... Anna   _________________ Wicked Witch of the West: I'm melting! I'm melting! |
Posted on 17/06/10 11:34:33 AM |
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laddition
femme fatale Posts: 585 Reply  |
Re: New Layer via Cut
I have the same problem, and i can't fix it.... _________________ Mais je me connais, je lâcherais pas l'affaire.... Je vais piquer de grève comme on pique une colère... Plus têtue que tous les vieil homme et la mer... Pour que continue le combat ordinaire! |
Posted on 17/06/10 2:28:10 PM |
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idwilson
* Posts: 2 Reply  |
Re: New Layer via Cut
I think you're being bitten by anti-aliasing on the diagonal lines. Turn the option off before you do the selection (and ensure you have a 0px feather) and you should be OK. In the attached screen grab, the upper selection was made with anti-alias enabled; the bottom one with it disabled. Interestingly, the navigator window shows a white line which is absent in the original... Hope this helps, Ian.  _________________ Ian Wilson Cambridge |
Posted on 18/06/10 05:44:36 AM |
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Nick Curtain
Model Master Posts: 1768 Reply  |
Re: New Layer via Cut
Hi Anna This would seem to have something to do with the screen drawing issue that Steve answered in response to Mark's layer style question. I created a file 8 X 12 inches at 300dpi and filled the background with black. I then drew a rectangle and went to 'new layer via cut'. The white lines appeared as you and Ian discovered. I then zoomed in to 66% and the lines disappeared. Naturally, the new black square became lost against the background, so I loaded its shape as a selection and on a new layer above created a white stroke border of 1px, so I could find where the square was sitting if I needed to check. It's interesting that the lines do not appear at any zoom above 66% however, if I zoomed out (CTRL -) through all steps down to 5%, the white lines become visible on alternate parts of the square and some edges are stronger than others. I flattened the image having dis-enabled the stroke layer and saved as a JPEG, which was viewed in Windows picture viewer and no sign of any lines at any magnification. Steve, in your experience, is this a known issue? Nick |
Posted on 18/06/10 10:17:45 AM |
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Steve Caplin
Administrator Posts: 7072 Reply  |
Re: New Layer via Cut
This is an anti-aliasing issue, as idwilson pointed out. Here's what's happening: Photoshop is anti-aliasing the edge of the selection, which means blending it off to transparent using increasing degrees of transparency in the pixels. It does all this within the width of a single pixel, so it's a very fine line. The trouble is, it's also doing the same thing to the background. Hence the gap. This isn't new behaviour, it's always been that way. Can I ask: why do you want a new layer via Cut? If it really bothers you, then try new layer via Copy, load the copy as a selection, reduce 1 pixel, then remove this from the underlying layer. You could even write a simple action to perform this. |
Posted on 18/06/10 10:30:28 AM |
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Nick Curtain
Model Master Posts: 1768 Reply |
Re: New Layer via Cut
Steve The part I don't understand is that if it's an AA issue, then why goes the gap not increase in size as you zoom into the image, instead of disappearing? Personally, I have never used this method and always punch the subject onto a new layer via copy (CTRL J) Nick |
Posted on 18/06/10 11:00:00 AM |
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idwilson
* Posts: 2 Reply |
Re: New Layer via Cut
The scaling issue is different, I suspect. This will be related to the way in which the image is filtered to make it larger or smaller: a simple rounding error in the calculations can make details appear and disappear depending on the scale factor applied. We're already used to this, as "jaggies" are visible when the scale factor is something other than 12.5%, 25%, 50% etc. They don't actually exist, of course, but are just an artefact of the scaling. My guess is that our anti-aliased lines are suffering the same fate... Ian. _________________ Ian Wilson Cambridge |
Posted on 18/06/10 11:56:05 AM |
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tooquilos
Wizard of Oz Posts: 2920 Reply |
Re: New Layer via Cut
Thank you Ian Nick and Steve for your replies and advice. Ian the anti alias trick works! Nick, you are correct. The percentage of the document seems to be another factor determining whether the white line appears or not. When its on the screen as a Photoshop document the white line appears. Once its saved as a jpg the line has gone. Its never occurred to me to look at the percentage size before. Steve, quite often when Im breaking apart an image to animate, I need to put various parts on different layers. Using New layer via cut has been my preferred way of doing it however Ive just tried new layer via copy and reducing it by 1px and yes, it is a much more straightforward way of doing it. Anna
_________________ Dorothy: "there's no place like home!" |