FS5: FS5 Highlight Artifacts.. Another Imaging problem and a Workaround

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dvbrother

Well-known member
I have been using the FS5 for about three weeks now, and have had the time between actual shoots to do some testing. Overall, I like the camera, and I am learning how to get the best from it and customizing it to my style of shooting.

There is a highlight fringing artifact issue that nobody has yet talked about. It is the same issue that appears on the FS700 and I assume other Sony FS cameras. Here is my brief blog entry about it.

http://in-todd-we-trust.blogspot.com/2016/01/sony-fs5-highlight-fringing-artifacts.html

The solution is to shoot in UHD, where the artifacts do not appear. The problem only exists in 1080p, in both internal and external recording.
For 1080p recording to the Atomos Shogun, I have sidestepped the problem by setting the FS5 to UHD recording, then setting the HDMI output to 1080p. Thus, the Shogun gets fed a 1080p signal that doesn't have the highlight fringing problem. Check out the video below.


Unfortunately, this solution requires an external recorder, and I think also reduces the bit depth of the final 1080p file to 8-bit instead of 10-bit because setting the FS5 to UHD is 8-bit 4:2:2 out only.
 
There was a similar artefact on the FS100 that could be reduced significantly by turning off any sharpening.

Is the aliasing affected by exposure i.e if you come down bit does the aliasing continue to be present?
 
Nirv said:
There was a similar artefact on the FS100 that could be reduced significantly by turning off any sharpening.

Is the aliasing affected by exposure i.e if you come down bit does the aliasing continue to be present?
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I have the Detail set to -7, which is the lowest it can be set on the FS5.
Regarding exposure, interestingly, since it happens with specular highlights, reducing exposure doesn't solve it. Counterintuitively, OVERexposure actually helps. I think it helps because the darker areas get brought above a certain threshold.
This really is only a problem in SLOG2 and 3. The other gammas don't have this problem. But it would be nice to know you can shoot 1080p SLOG footage without worrying about ugly highlight artifacts which, to me are a dead giveaway of Sony cameras and a non-cinematic look.
 
Ugh, it still has highlight fringing? WTF is sony doing? It really can't be that hard to remove that effect. They still seem to have it on pretty much all their cameras <FS7 to some degree...
 
C'mon, everyone knows cameras aren't meant to be pointed at stuff with that is 'highlight' like. No one should expect more than that from a $5600 camera! You're just using the camera wrong! (sorry, had to... haha)

Although after watching the video .. what the heck??? I don't come from an FS100 background so haven't seen that before. Fairly distracting... Hopefully that only occurs in very unique scenarios though.
 
chappelldigital said:
Fairly distracting... Hopefully that only occurs in very unique scenarios though.
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If by "unique scenarios" you mean interior shots with bright windows in the background, forest shots with sun peaking through trees, sunny exteriors with chrome bumpers on cars, glass-front buildings, shots with neon signs or any practical light bulb in them, then yes. :D
 
BeeHop said:
That footage is disgusting. :Drogar-Love(DBG):
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I just want to be clear that I DO, in fact, really like the camera. And the workaround is easy: either 1) don't shoot in SLOG or 2) shoot in UHD.

But...for those of us who were wanting the benefit of 10-bit 4:2:2 AND SLOG, we are out of luck. Strange how cameras never give us exactly what we want or need. There ALWAYS seems to be a compromise.
 
olof said:
Strange I never found this in any of my footage.


I have short 20 + hrs and never saw this at all in the FS5 footage 1080 or UHD...
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Regarding the video you posted, there is nothing in the shot that would trigger the highlight issue, IMO. It usually occurs in hard-edged areas where a clipped highlight meets a dark edge. So it usually appears on an area that's in focus. Had your shot been focused on the windows in the background, it may have shown up. Again, this only happens in 1080p SLOG modes. Have you shot much in that setting?
It's possible that I have a bad camera, but I've seen this on other people's FS5 footage on Vimeo. I think I'll go look for that right now.
 
You can see it in this video at :04 on the girl's shirt.


And it's all over this video, which has otherwise been considered a positive example of FS5 footage. Look at her legs and shoes at :29, her right arm at :40, the lights in the background at :53 and in basically every shot with the sun in it.


The bummer is that the person who shot this said it was in Cine4, which means it's not just SLOG where this problem appears.

I found other examples too. It seems to be particularly apparent on slo-mo footage.
 
I don't know, that last piece looks pretty sick to me! I looked at it a few times and didn't really see much that stuck out to me on either video.
 
swanny said:
I don't know, that last piece looks pretty sick to me! I looked at it a few times and didn't really see much that stuck out to me on either video.
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Certainly, a compelling edit or story is going to help disguise the issue. But the fact is, if I shot that footage on a GH4, or a C100, it would not show up. Of course, those cameras can't shoot 240fps. Personally, that artifact drives me nuts. It's a pet-peeve of mine and so my eye always goes right to it whenever I see it. And since our eyes are usually drawn to the brightest area in the frame, it is very easy to spot.
 
I was looking for it and only saw it once and wasn't in the least bit distracting to me. Maybe I'm blind tonight
 
Looks like somebody else discovered this problem several weeks ago. And the comment section on the Vimeo page is informative.

 
Ive been seeing the fringing in 240fps on the FS5 (because it's the only time I use HD on my FS5) Don't know how to recreate it regularly unlike the noise reduction tearing in UHD. It does seem to often appear around specular highlights and I also see it in Cine 4. But when it shows up, it wrecks the shot. Sparkly magenta and black splotches on the frame. Completely different from aliasing though. Looks like sensor bloom, and I suspect it's fixable through firmware.
 
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Doug Jensen said:
Should I be seeing fringing here?

https://vimeo.com/151976039
Password: FS5
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Interesting. Don't know what to tell you. Especially since there are plenty of anecdotal reports from others who have experienced fringing problems (see the post above yours). It seems that those who have seen it also say it isn't necessarily consistent, which is unfortunate as it makes it harder to troubleshoot. For what it's worth, it seems to show up more in slo-mo footage, and my shots of the statuette were shot at 30p. I may go back and do a test at 24p to see if that makes any difference. These are just shots in the dark, though. I will say I really like the contrast of your custom setting. Care to share those settings?

And in the interest of gettting to the bottom of this, what lens did you use? I'm wondering if the Auto-Correction on the 18-105 kit lens might have anything to do with it.
Was the Color Gamut on your SLOG2 footage the SLOG2.cine/3200k? Your SLOG footage seems more saturated than mine.
 
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The FS7 has magenta fringing in CUSTOM Mode which is similar to the above examples, in CineEI mode there's none.

The aliasing issue seems to have been around a long time from the FS100, FS700 and now the FS5 I think it has to do with how the individual channels are clipping i.e. 1 or 2 hard clipped which may be the reason it's not consistent. The aliasing in those FS5 clips are exactly where I would've expected to see aliasing in the FS100.
 
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