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How do I avoid Halo's?
I have receintly posted a photograph of a Buzzard in flight and it has been mentioned that there is a faint halo,
I am not sure how to sharpen the image without creating a halo, I use the method in Digital Basics by Art which I did 3 times....
Thankyou in advance for all advice
Jacqui
What I do is, Quick Mask the bird that I'm working on and only sharpen that part,
not touching any sky etc. With the bird now on its new layer, that allows me to
apply any noise reduction to the background.
Doug
If the BG is blue sky, you can use the magic wand tool, click on the sky, then inverse and contract by 1 or 2 pixels and then sharpen. Afterwards you can expand by 3 or 4 pixels, inverse and apply NR on the BG if necessary. If the BG is busy then this procedure wouldn't work as easily.
Jacqui another thing is trying to expose so you don't have to use shadow/highlight If you photograph a buzzard from below the basic exposure is at lest +1 on ambient You are photographing the shadow side of the bird I don't use it as much as I used to and when I do is very light
When I do use it my basic settings are 12% for amount and tonal width 24% for radius When you go stronger the blacks turn to mush !!!
Jacqui,
I do what Doug mentioned. Example: Bird in clear blue sky.
I make a selection on the sky, inverse the selection, contract it and feather it. That gets the selection out of the sky and onto the bird. Then sharpen the selection. Since the contrast between the bird and sky is large, sharpening that edge is not really required and will produce halos. Sharpening changes contrast between adjacent pixels by modifying them - that causes the halos.
Artie's method does not account for this as sharpening is applied to the whole image. If you sharpen and get halos, more work is needed to selectively sharpen. Artie will selectively sharpen when required.
Thankyou all for the replies it is much appreciated :-)
However I dont seem to be able to contract an image in CS2 as the option is not available ? (I went into select-modify)
Jacqui
I don't remember exactly but I thought Select - Modify - Extract/Contract is an option in CS2, too. Same applies to the magic wand tool. Was this introduced in CS3?
Jacqui,
You need to make the selection you are going to copy first on a background copy and the Select>Modify>Contract will be available.
Thankyou Robert
I have managed it now :-)
Jacqui
Great Jacqui, glad I could help.
Working at 100% is the one thing no one mentioned, but it's critical. If you're zoomed out to 25%, you won't see the halo until it's too late. If you work at 100%, you can continue sharpening until a faint halo is visible. Any more than faint, and you'll have gone too far.
Good point David. I do that but forgot to mention it.
Hi
Usually I don't care about the Halos, until the finished is totally ready for saving for web. If there are Halos, I just use the "Blurr-tool" (is this the right english name), zoom in to 1000 % select the tool's size 2 pixel, strength 85% and then I just delete the Halos with it. Very easy and fast.
All those selective methods need so much time. When I edit pictures for websites, I just use my own PS-action...then I have good sharpness and the right size in 5 seconds...
Jan,
I agree that I don't have the inclination for a lot of manipulation to rid myself of halos on a small JPG and do as you do most of the time. The original poster wanted to know how. So he knows and can now do it if he wishes. You points are well made and I glad you brought it up because I am like you and don't mess around with them often.
A selection on a sky BG is very easy though and I would suggest less time consuming then remove halos after the fact as you suggested though I have used the method that you discuss,
Thanks for posting.
