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-   -   Tips for Limiting Chromatic abberration (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/109375-tips-limiting-chromatic-abberration.html)

Brian Luce December 2nd, 2007 07:24 PM

Tips for Limiting Chromatic abberration
 
There's a lot of talk of CA, but there isn't a resource that spells out guidelines for preventing CA. Here are some instances that have caused CA for me.

For starters,

1) Avoid shooting through the long end of the lens

2) Avoid shooting with lens wide open

3) Avoid Bright/contrasty backgrounds.

What are some others?

Bill Ravens December 2nd, 2007 09:07 PM

there's a few plugins that will remove CA. The one I use works with VirtualDub...not perfect, but, better than no correction.

Brian Luce December 3rd, 2007 01:45 AM

Quote:

Originally Posted by Bill Ravens (Post 786126)
there's a few plugins that will remove CA. The one I use works with VirtualDub...not perfect, but, better than no correction.

Thanks by I was thinking more along the lines of camera/lens settings. IE avoiding it in the first place.

Tom Hardwick December 3rd, 2007 03:04 AM

It sounds to me Bruce as if the fear of CA could be limiting your shooting options somewhat. Shooting wedding guests at the long end of the zoom and at maximum aperture sure does raise the CA levels, but at the same time the flattering perspective, the differential focus and the lack of intimidation gives me the portraits I want.

You might say that you shouldn't shoot at full wide because of the barrel distortion so prevalent in camcorders, but most clients want the perspective shots and won't be looking at the vignetting way up there in the corners.

tom.

Bill Ravens December 3rd, 2007 08:23 AM

Brian...

There's not much you can do to reduce CA other than the items you listed. It's a weakness of the lens design. The most effective option, of course, is to change your lens. You may want to consider more fill light to reduce contrast, but, the wedding party might object as it's rather intrusive.

Shai Camerini December 3rd, 2007 09:25 AM

can someone post a ca Sample? a Photo or something
 
what is that anyway?

Tom Hardwick December 3rd, 2007 09:35 AM

Chromatic abberation? When not all colours are brought to the same focus point. Jeff explains it well here:

http://www.dvinfo.net/articles/optics/lensdefects.php

Seun Osewa December 3rd, 2007 09:38 AM

What's the "long end of the lens"? Is it zoom?

What's "wide open"? Is it the iris setting? ???

Tom Hardwick December 3rd, 2007 09:42 AM

The long end is the longer focal lengths. Wide open refers to the iris, yes.

Brian Luce December 3rd, 2007 12:23 PM

I've also heard of shooters getting CA at the wide end of the lens, anyone experience this?

Shai Camerini December 3rd, 2007 01:10 PM

Thanks Tom

Adam Letch December 3rd, 2007 05:58 PM

Depending on how you shoot
 
whether tripod or shoulder, I find if I'm on a tripod I shoot using the flip out LCD, and I use the hoodman on it to reduce glare and solarization. I've found that I've learnt to look out for it, and as such I will pull back the zoom slightly to either get rid of the CA or diminish it.
The EVF you can probably do the same, but either it doesn't resolve enough to see it, or I just haven't observed it yet, as it was only on my last shoot I bothered to pay attention to it.

Roman Schoen January 25th, 2020 07:28 AM

Re: Tips for Limiting Chromatic abberration
 
Quote:

Originally Posted by Bill Ravens (Post 786126)
there's a few plugins that will remove CA. The one I use works with VirtualDub.

I'm searching such a VirtualDub-plug-in to reduce chromatic abberation in post. Has someboy a name of a plug-in?


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