GH4 What is this purple halo???

Barry_Green said:
I would vote against it being chromatic aberration, because we're not seeing any green
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I never saw any green with my Zeiss ZF 50mm f/1.4, but lots of purple-ish looking edges when shooting with my GH3 camera. Micro 4/3 lenses never showed this issue, which I'm guessing was the in-camera correction.
 
macgregor said:
Hello everyone.
There's something a bit odd related to CA.
I've seen lots of CA in shots on the GH4 taken with lenses that in other cameras did not produce that much CA. And it's not a matter of 4K resolution or sensor crop because it's visible at 1080p. And I'm talking about premium glass. I'm going to do a couple more rests but I feel something odd is going on here. Perhaps the OLPF is increasing CA? Any other ideas? Maybe the adapter is off by a micron?
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Fast lenses always tend to have that problem. Digital tends to make it worse for older lenses due to microlens interaction. With the GH4, since the sensor is a new one, it could be that there's been a change to the microlens layout. Or even the way light is collected in the well of the individual photosites.

If the adapter is off, that'll affect focus (sharpness) instead.

TheDingo said:
I never saw any green with my Zeiss ZF 50mm f/1.4, but lots of purple-ish looking edges when shooting with my GH3 camera. Micro 4/3 lenses never showed this issue, which I'm guessing was the in-camera correction.
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In-camera correction won't correct that: It's just that m4/3 lenses, being a modern lens designed for digital sensors, avoids that problem.

This reminds me of the time I bought the Nikon 85mm f/1.8D... 3 months later the AF-S version is released, and boy was I kicking myself. The older lens which was designed in the film era has the above problem in spades at f/1.8. The new AF-S lens just doesn't have it.
 
TheDingo said:
I never saw any green with my Zeiss ZF 50mm f/1.4, but lots of purple-ish looking edges when shooting with my GH3 camera. Micro 4/3 lenses never showed this issue, which I'm guessing was the in-camera correction.
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I've got that same lens, and it shows a lot of chromatic aberration (purple and green) at wide open. You can actually even get it to shift colors, it depends on the focus point -- focus a little closer, it would turn a little green; focus a little further away, it'll go purple...
 
Barry_Green said:
Funny, I linked to wikipedia and forgot that I'd actually done an article on this, years ago...
http://www.dvxuser.com/articles/article.php/2
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So Barry, do you think this still applies?

" High-end professional cameras have “lens flare” setup menus which are designed to instruct the camera in how to compensate for this particular artifact. Lower-cost HD camcorders typically don’t have those menu settings, so they don’t give you that option."

HOw is that some lenses in the same exact camera show this effect wide open and some others (better ones) don't?
 
Finster said:
An earlier post mentioned using a UV filter. This seems to help some.
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Glad it helped. It would interesting if you could take a comparison shot both with and without the UV filter so we can see the difference. If the UV sensitivity of the sensor is part of the issue with this camera (especially at 4k) it would be helpful to see how much.
 
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