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A6000 highlight peaking issue??
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PostPosted: Fri Jan 02, 2015 9:17 am    Post subject: A6000 highlight peaking issue?? Reply with quote

I'm noticing this odd issue with my Sony A6000.
When I shoot at night, I get this weird artifacts. Any hints?





PostPosted: Fri Jan 02, 2015 10:40 am    Post subject: Reply with quote

I assume these are grabs from your viewing screen. I hope so. The camera is fooled by the high contrast and the focus peaking is showing I get it sometimes. If you switch to magnified view these artefacts should go. Is your lens stopped down?


PostPosted: Fri Jan 02, 2015 5:13 pm    Post subject: Reply with quote

philslizzy wrote:
I assume these are grabs from your viewing screen. I hope so. The camera is fooled by the high contrast and the focus peaking is showing I get it sometimes. If you switch to magnified view these artefacts should go. Is your lens stopped down?


These are crops from original raw files. Yes, if I remember correctly I stopped down.
The highlight issue is baked in to the pics.

Here's one of the original pics resized:



PostPosted: Fri Jan 02, 2015 5:54 pm    Post subject: Reply with quote

I think Phil is probably on target. I don't own an A6000, but a NEX 7 and I've owned it only for a couple of months, so still getting used to it and its focus peaking feature. The upshot to it is that the focus peaking can fool you into thinking you've nailed focus, when you haven't. Over at the talkemount forum (or was it here?), one of the people there suggested I set my focus peaking to "medium." I had it set to "high." Setting it to medium reduces the "false positives" I've found. But I've also found that if the contrast in the scene isn't sufficiently high enough, no focus peaking coloration is evident. So now I will switch back and forth as required. But mostly now I make use of the magnification presets to confirm focus.

Last edited by cooltouch on Fri Jan 02, 2015 8:25 pm; edited 1 time in total


PostPosted: Fri Jan 02, 2015 6:04 pm    Post subject: Reply with quote

I'm confused... the issue I'm talking about is not the focus, in the examples I posted is not what I'm concerned about.
Instead, what I'm not getting is the crazy hot blueish halo around some neons/highlights in the pics.


PostPosted: Fri Jan 02, 2015 8:30 pm    Post subject: Reply with quote

I understand. But if the lens is out of focus, those halos will be exaggerated, because the light will be circles or irregular blobs instead of points of light or lines.

Have you noticed these same artifacts with other lenses? Might it be a chromatic aberration issue you're having with only one lens?

If it's CA, typically the situation improves as you stop the lens down further. You mention you did stop down the lens. So no difference between that f/stop and wide open?

Lastly, are you seeing any evidence of these blue halos as you view the scene through the camera's viewfinder?


PostPosted: Fri Jan 02, 2015 8:53 pm    Post subject: Reply with quote

All good points:

cooltouch wrote:
I understand. But if the lens is out of focus, those halos will be exaggerated, because the light will be circles or irregular blobs instead of points of light or lines.

Have you noticed these same artifacts with other lenses? Might it be a chromatic aberration issue you're having with only one lens?


Yes, it happens with other lenses too.

cooltouch wrote:
If it's CA, typically the situation improves as you stop the lens down further. You mention you did stop down the lens. So no difference between that f/stop and wide open?


I've had the same issue in other pics, with the moon for instance. I'll double check, I think at f/2.8 or f/4 was getting better.
That said, I don't have this issue on my 7D. Pictures can be out of focus, but no highlight/blue halo issue.

cooltouch wrote:
Lastly, are you seeing any evidence of these blue halos as you view the scene through the camera's viewfinder?


Hm... I'll double check that too, but I don't remember the halo on the viewfinder.


PostPosted: Sat Jan 03, 2015 12:32 am    Post subject: Reply with quote

Is Auto White Balance on? See how light on walkway is blue? Is that how light was then or is this camera (awb) error?


PostPosted: Sat Jan 03, 2015 1:32 am    Post subject: Reply with quote

Not seen this issue with my A6000.


PostPosted: Sat Jan 03, 2015 6:12 am    Post subject: Reply with quote

Another quick test.
This time with OM Zuiko 50 f/1.4, shot @ 2.8 if I remember correctly.




It is definitely something that has to do with blue highlights/neon.

I searched around and it seems it's something pretty common with the A7s too!
There are different threads already:
http://www.dpreview.com/forums/post/54480184
http://www.eoshd.com/comments/topic/7172-sony-a7s-color-channel-clipping-issues/
http://www.dvxuser.com/V6/showthread.php?327633-A7S-colored-highlight-peaking

From the last one it seems there's a workaround, even though I didn't carefully read it yet:
http://www.dvxuser.com/V6/showthread.php?327633-A7S-colored-highlight-peaking&p=1986476855&viewfull=1#post1986476855

It is quite annoying though... Sad


PostPosted: Sun Jan 04, 2015 10:50 pm    Post subject: Reply with quote

Maybe it is UV light. That was my first impression. It wouldnt be in focus and I wondered if the blue artefacts are 'UV bokeh'. But I thought the camera had a filter over the sensor.

Perhaps put a UV filter on the lens - not a skylight - and see if it happens then.


PostPosted: Thu Feb 19, 2015 8:06 pm    Post subject: Reply with quote

My NEX5N does it too with some neon/LED lights(like someone says in that thread referred to). Have seen it from blue LEDs indoors and a lit show-airplane in the dark. It's in the raws and has nothing to do with peaking.

Edit: Just tried taking a picture of my modem's blue LEDs..camera engaged the AF assist light, reddish, and in it the symptom was at 300%, but in the final picture it isn't quite as bad. Just as bad as those blue spots in the OP's pictures however. Stay away from blue LEDs.


PostPosted: Fri Feb 20, 2015 2:05 am    Post subject: Reply with quote

I've recently noticed something similar to this with my NEX 7. I use a digital camera to make digital duplicates of slides instead of a scanner these days, and recently I've begun using my NEX 7 for this. I tried it out on a roll that I developed that came out having a slight blue cast to it. Not sure what caused the blue cast. It might be because it was an old roll of film, or maybe I missed the right temperature during development.

So anyway, instead of just faithfully recording the images with their slight blue cast, with some of the slides, the images came out with wildly exaggerated blue tones to them. Here's an example:

This is what the slide should look like:


And this is the way my NEX 7 recorded it:


I've also noticed that if I photograph a subject against a blue background, the entire photo will have taken on a strong blue cast. For example:


It just seems to me at this point that the NEX 7 sensor is way too sensitive to blues. I haven't noticed the flare the OP showed, but I wouldn't be surprised if my NEX would exhibit it under similar conditions.


PostPosted: Fri Feb 20, 2015 4:36 am    Post subject: Reply with quote

I noticed the highlights shows artefacts on my 5N when I taking photos of the Observation wheel here(see the lower part of the photo). There is nothing I can do unless lowering the exposure.