Color separation using a fisheye attachment

Mech

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I've been doing photography as a hobby for a while now, and last year I got a cheap fisheye conversion lens (where you can detach the fisheye and be left with a macro lens.) The Macro lens works great, but towards the middle to the outside of the picture on the fisheye, it looks like the color starts to separate from each other. Actually, the entire photo looks like it, but it gets worse towards the edge. Is this because it's just a cheap-o? I do leave on the UV filter and the macro, so would that affect it? I'd really like to just get a real fisheye lens, but unfortunately it's not in the budget right now.

I have both a Nikon D50 and D60.
 
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It sounds like you are experiencing Chromatic aberration.
Basically, different colors of light have different wavelengths, so as the light is bent by the lens elements, the colors come out of alignment. This is usually worse as you get away from the centre of the image.

Better quality lens designs strive to avoid this, and as you would expect, cheap lenses don't correct for it as well, or at all.

I also wouldn't suggest using something like that, with your UV filter. Actually, most digital cameras have a built-in UV filter over the sensor, so all your external filter is doing, is providing some physical protection, but because the light has to pass through it as well, it could be hurting the image quality.
 
UV filters always bug my stuff. It could be a combination of both.
 
Thanks, I will definitely give it a try. Not sure why I never thought to try it without the UV filter until I started writing this.

Yeah, and I was mostly using it to protect from scratches.
 
T-shirt cleaning. That's what I use them for. Having a protective filter means I don't need to go through with the anally retentive cleaning procedures some people here use (2 microfibre cloths? I mean really!). Mud on the lens, T-shirt to the rescue. :)

Big Mike is right though. UV filters have little to no impact if they are quality and the light rays hit them nearly orthogonally. With fisheye lenses and ultrawide angle lenses UV filters perform at their worst and can induce CA.
 
the short answer to your question is yes.
the fact that its a ****ty aux lens is what makes the IQ terrible around the outside.
i have one myself, and although its a fun toy to play with with once in awhile, the IQ makes me not use it for anything worthwhile.
 

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