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View Full Version : Image resizing, fighting jaggies!


Tad
06-11-2005, 03:43 AM
OK so i'm working with some images I took today with my digicam,
I'm wondering, is there some way to know what percentage you should size an image
down, to not have jaggies appear.

I know a simple slice in half(50%) works great,
but the resolution i'm trying to get isn't quite so even,
and it's giving me some jaggies..

any tips would be great.

thanks.

theGuest
06-11-2005, 05:42 AM
Are you sure you're not viewing your document at an odd zoom percentage? ;)
That's usually what the cause of this issue is.

I have yet to have PS create jagged edges when scaling 'down'. Scaling down is preferrable to scaling up. Scaling down usually 'smooths' the photo out.

Check your zoom level. :bounce:

Tad
06-11-2005, 09:56 AM
hah,
yeah it's not the zoom :P

and i haven't really had that problem much either in the past..
but for this particular image I did..

ended up just trying different sizes that were close to what I was aiming for till Ifound one that worked..

kraal
06-11-2005, 01:59 PM
i agree that it may be just a screen redraw issue.... did it print with jaggies?

try setting view to print size and then see if jaggies are present

malcolmvexxed
06-11-2005, 06:09 PM
just to clarify first, do you understand the difference between bicubic and nearest neighbor ?

RiKToR
06-12-2005, 03:38 AM
He's talking about when you utilize the navigator to zoom in and out of document. Usually intervals of 1/3 causes the "jaggies" you refer to such as 33% & 66%. usually cranking to the nearest interval such as 30 or 40 for 33% & 60 or 70 for 66% and so on. This does happen on thirds above 100% and below 25% as well, it also is universal for PC or Mac.

Tad
06-12-2005, 03:52 AM
ok you guys don't know me, but give me some credit, I know how the zoom tool works! haha

i'm looking at it at 100%(actual pixels) AFTER resizing the image resolution down
from the original 3mp image to the size I want it to end up being(usually around 900 width..)

I haven't been interested in printing my images at all as of yet,
it's all digital so print size is really irrelevant to me.

Basically it is similar to what happens when you zoom out to like 33% or something,
only thing is it's the actual image that gets the jaggies, not just how photoshop is showing it at that moment..
And it's pretty subtle and usually turns out ok.. but I can be a bit of a perfectionist at times..

I don't however know the difference between bicubic/bilinear/nearest neighbor..
I usually just leave it at default when changing image resolution.

malcolmvexxed
06-12-2005, 06:10 AM
Basically it is similar to what happens when you zoom out to like 33% or something,
only thing is it's the actual image that gets the jaggies, not just how photoshop is showing it at that moment..
And it's pretty subtle and usually turns out ok.. but I can be a bit of a perfectionist at times..

I don't however know the difference between bicubic/bilinear/nearest neighbor..
I usually just leave it at default when changing image resolution.the thing you describe, which is like the 33% zoom edging is usually caused by people reducing their images with nearest neighbor (which samples and leves edges, usually done for line art files) instead of bicubic which is more of a smoothing reduction usually done for colored jpegs, web graphics etc. I jus twonder if the settings might have changed for this image somehow or gotten acicdentally hit? try it with the different drop down options and see if it looks different.

Tad
06-12-2005, 06:30 AM
Hmm,.. CCCOOUlllda been,
but it was a few days ago, so I don't remember,
and I tried a few different resolutions in that similar range and found one that was ok.

I'm pretty sure it wasn't on nearest neighbor,
that one I do know what it does.. and the results are far more noticeable
than the problem i'm taking about.

think a mix of nearest neighbor and bicubic, maybe 25% n.n. and 75% bic.

as I said,
subtle..

might just be one of those things you have to deal with..

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