# Speedboosters and chromatic abberation



## mensaf (Sep 10, 2018)

Is CA a natural consequence of using a speedbooster? I have an EF to EF-M speedbooster that I use on my M50 and when taking photos yesterday, I noticed it for the first time ever. It was an overcast and somewhat humid day, so I'm not sure if that factored into anything, but it was only present in a handful of pictures I took at an outdoor Strongman/Strongwoman competition. I'm pretty new to accessories as my equipment has always been pretty simple and mainly shoot video, but it's something I'd like to be prepared for in case I'm ever out on a job. I've included a few images where it was most pronounced (woman on the right's face/body and man's forearms) and one (the vertical shot) in the same conditions where it pretty much disappeared.

If it matters:

Body - EOS M50
Lens - 85mm F/1.4 IS
Speedbooster - Custom made of Viltrox parts

Would definitely appreciate any insight as I'm trying to understand how some of this works as this hobby becomes something more. Thanks!


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## Ozarker (Sep 10, 2018)

There is an added glass element, right? That's the problem.


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## mensaf (Sep 10, 2018)

Think an ND filter would help with that?


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## Mikehit (Sep 10, 2018)

I am not sure I would call that CA to be 'quite pronounced' but we all have our own expectations. CA happens most in areas with high contrast so if it was a real issue I would expect to see it around the I would mounts for the indicators or around the bumper stickers.
The image with the woman urging on the competitor, it seems to be more about subject movement - what shutter speed were you using as a matter of interest?

The speedbooster had an internal lens and the more glass surfaces you have the more likely you are to have aberrations.


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## mensaf (Sep 10, 2018)

Mikehit said:


> I am not sure I would call that CA to be 'quite pronounced' but we all have our own expectations. CA happens most in areas with high contrast so if it was a real issue I would expect to see it around the I would mounts for the indicators or around the bumper stickers.
> The image with the woman urging on the competitor, it seems to be more about subject movement - what shutter speed were you using as a matter of interest?
> 
> The speedbooster had an internal lens and the more glass surfaces you have the more likely you are to have aberrations.


I was between 1/2000 and 1/4000 for those shots.

I guess I say it's pronounced because I've never actually seen it in anything I've done before. I was more curious than anything else. Thanks for the explanation!


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