Halos!? I'm no angel. Help Please

08/02/2005 03:26:45 PM · #1

I managed to drag myself out of bed this morning to get some sunrise pix.

I'm still trying to get decent images out of this PowershotA80 and I notice these halos on a lot of my shots in the high contrast areas. Sharpening makes them worse.

Is this chromatic aberration or what? They are on the image straight out of camera. I have a feeling it's incurable, but can anyone give me some pointers on how to avoid them, or at least, how to minimize them in PS?

Here are some shots I took today. I didn't sharpen them.

I'm hoping this won't be an issue when I get my new DSLR, but I'd like to know what's causing it.

Thanks,
Roxanne

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

08/02/2005 03:29:01 PM · #2

The first thing to check is whether your camera settings include any sharpening. If so, try turning that off.

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

08/02/2005 03:31:36 PM · #3

You can replicate the effect on a "good" photo by applying excessive Unsharp Mask in post-processing. Check out this pBase gallery for some examples.

kirbic

Canon EOS R5

Canon RF 24-70mm f/2.8 L IS

08/02/2005 03:32:14 PM · #4

Originally posted by GeneralE:

The first thing to check is whether your camera settings include any sharpening. If so, try turning that off.

Precisely. Turn you camera's setting for sharpness as far down as it will go, and then sharpen as required in post-processing. you should definitely be able to get a better result that way. Most small-sensor cams have pretty aggressive in-camera sharpening assuming that most users will want to do little or no post-processing.

tazza

Canon EOS-350D Rebel XT

Tamron SP AF 28-75mm f/2.8 XR Di for Canon

08/02/2005 03:32:29 PM · #5

Can't turn sharpening on the A80, I'm afraid these halos are here to stay... I've noticed some on my pics too, to be honest you need to be looking hard to see them (100% crop). On a 7x5 print they're invisible
Looking forward to the dSLR days too!

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

08/02/2005 03:34:33 PM · #6

Originally posted by tazza:

Can't turn sharpening on the A80 ...

You mean can't turn it off, right? That's surprising for a camera which comes with full manual controls.

Message edited by author 2005-08-02 15:35:25.

08/02/2005 03:34:55 PM · #7

Thanks tazza, I've just gone through all of my settings and couldn't find any sharpening feature.

Well, I'm glad it's not just me, but I wish there were a way to fix them.

Thanks everybody.

Tamron SP AF 28-75mm f/2.8 XR Di for Canon

08/02/2005 03:36:09 PM · #8

Originally posted by GeneralE:

Originally posted by tazza:
Can't turn sharpening on the A80 ...

You mean can't turn it off, right? That's surprising for a camera which comes with full manual controls.

Maybe I'm missing something. I am missing the manual, but it's fairly simple to use and there is nothing about sharpening that I can find.

tazza

Canon EOS-350D Rebel XT

08/02/2005 03:38:49 PM · #9

Oops, I've just noticed it's possible to set the camera to "low sharpening" in the "effects" sub-menu from the function list ! I never tried it before (obviously) Maybe that'll help

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

08/02/2005 03:40:12 PM · #10

Originally posted by greatandsmall:

Thanks tazza, I've just gone through all of my settings and couldn't find any sharpening feature.

Well, I'm glad it's not just me, but I wish there were a way to fix them.

Thanks everybody.

Try running the "Find Edges" filter. When/if you get a selection running where the halos are, use Edit > Border to create a brader selection which should include the halos. Feather the selection, and use it as a mask to apply a Tone Curve (New Adjustment Layer > Curves) to darken up the haloing, or you can try applying the Burn tool to the selection for create a more localized effect. If you zoom way in, you can do that anyway, without any selections at all, just careful "painting" with the mouse (a tablet is good for this type of work).

08/02/2005 03:44:53 PM · #11

Thanks GeneralE. I'll give that a try. Think I'll put a tablet on my wish list.

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

08/02/2005 03:45:56 PM · #12

Originally posted by greatandsmall:

Maybe I'm missing something. I am missing the manual ....

See if this link gets you to where you can download the manual in Acrobat 6/PDF format:

//alpha03.c-wss.com/inc/ApplServlet?SV=WWUCA900

08/02/2005 03:53:09 PM · #13

Link doesn't work for me. But I will go to the Canon site and look it up.

Thanks again!