GH1 Color Shifting Issue

Obviously -- nobody's suggesting otherwise. And I've already pushed it over to the broadcast people to have them hand it over to the consumer group. I don't know anyone at the consumer group and so have no contacts there.

Firmware doesn't usually get added for any new features, but for bug fixes, yes. So therefore I would certainly expect that they'll be interested in seeing this and fixing it.

In the meantime, for those who are shooting now, the way to avoid it is to use those certain gamma curves that don't exhibit the problem.
 
stephenmick said:
If I remember correctly, "Standard" mode was clean, but "Smooth" and "Dynamic" showed the shift.
Click to expand...

You do remember correctly.

I did a bunch of testing on this with Stephen - and when I get a chance I'll post the clips I have from that (out of town right now and don't have that footage with me).

The blue shift seems to occur when a specific shade of blue is up against a bright background. That may sound like a really narrow set of circumstances - but just think about water against the sky... or white clouds against a nice blue sky... there are many times this could become an issue.

Honestly, if I hadn't seen it myself on two different GH1s I would have assumed it was a bad camera. But we've been able to recreate the problem on two different cameras.

After a lot of testing we there were only two modes that did not exhibit the problem - Standard Mode & Standard B&W Mode.

Every other gamma mode, regardless of framerate, resolution, shutter speed and aperture showed the same blue shifting issue.

And - as was mentioned - it was only seen when using the kit lens.
We could not recreate it when using a manual lens.

Now - this doesn't necessarily mean the issue lies in the kit lens - but unfortunately we didn't have any other micro four thirds lenses to test. I'd love to get another Panasonic micro four thirds lens so we can figure out if the issue is in that specific lens - or in the fact that the lens is communicating with the body in some way.

Yes, I know, the issue sounds bizarre and doesn't make any sense - but it definitely exists as far as I'm concerned.

If anyone would like to test it out (the more data points the better) - here is what I would suggest:

Get something light blue (almost teal) colored and put it up against a bright background (a blown out window... the sky, etc).

Tilt the camera up and down slowly, so that the bright background takes up more and less of the image...

You will only see the shift when you are actually recording.
I drove myself nuts for a while trying to recreate it just by watching for it - then eventually realized it only happens while recording.

If you find you can recreate it - let us know in this thread.
Might be helpful to find out if others can see the same thing we are.
 
Okay - I thought this stuff was on an external, but apparently it was on my laptop drive.
Just put it up on vimeo so you could see what we're talking about.

These clips were all shot on full manual mode with the kit lens.
I know they're short - but I was trying to keep the MTS files small so I could upload them unedited.

You'll have to excuse the cineform logo - I have the NeoScene demo, and it's now expired.
But rest assurred - the demo has NOTHING to do with this issue.
This color shift can be seen in the LCD while recording, on the original MTS files, as well as through a registered copy of neoscene (which Stephen has, and we used that day).



Keep in mind, I'm not doing anything here other than tilting the camera up and down.
That's it.

You'll notice the only modes that don't exhibit the color shifting are the two 'standard' modes (Standard and Standard B&W).
 
The only solutions we've found are…

- shoot without the kit lens
- shoot in "Standard" mode only

But that of course limits the camera's usefulness to me. Hopefully Panasonic will figure out what's going on at some point and fix it via firmware.
 
Question is, can you achieve a certain look through the film modes that cannot be achieved in post with a color grading tool?
 
Sure you could, if that's how you like to work.

Personally, I like to create a "look" in camera, making for as little color-grading as possible. My clients want and like this look. I could create it in post, but it makes more work that really isn't necessary.

Either way, when only two modes (standard and standard b/w) don't show this issue, then it's clearly something that should be fixed.
 
Very useful information here! I love this forum for stuff like this. Luis that is a very good test. I hope this get repaired in firmware. I wouldn't say the solution is to always shoot in standard though. It looks situational so I guess if you know you are going to have blue in your shot with your stock lens then switch to standard.
 
Nitsuj said:
so I guess if you know you are going to have blue in your shot with your stock lens then switch to standard.
Click to expand...

True - though I should also say, it's not just anything that's blue - it seems to occur with specific shades of blue...almost a teal color.

I need to dig up a shot I shot before the tests I posted above, while just playing around - I didn't notice it when shooting but when I went back home and looked over the footage I noticed someone's shirt flickering horribly...and it was bc she happened to be wearing a teal shirt. Very odd - but luckily I was just shooting for the fun of it..and it wasn't anything important.

I should also mention that I did some rough testing with other colors, thinking at first that it might have something to do with saturation levels or something like that - tried bright reds, oranges, greens.... nothing displayed the issue other than that specific shade of blue.
 
MR Fanny said:
wow...now that's an interesting find that should be made known to panasonic. would really render shots useless.
Click to expand...
I've alerted everyone I can think of at Panasonic, and sent them this video link. But the only people I've met are broadcast folks, I don't know anyone in the consumer company. Hopefully the people I sent the link to will know who to pass it on to.
 
This is so wierd. I just filmed a scene on the water, yesterday on my first day of filming my feature film and it was under the exact scenario mentioned above.

I used the kit lens, smooth mode, 1080, shooting on the ocean, blue boat in the foreground, against a blue sky.

Every time the boat bobbed up and down on the waves, it would shift the shade of blue. It stunk because it made the shot unusable, but I had blown out highlights anyway.

Still, I hope Panasonic gets right on this.
 
Barry_Green said:
Until then, I recommend either using the Standard gamma, or a manual lens, when shooting under those scenarios.
Click to expand...

Or a third option...

Add more light to the blue subject. I noticed that I had taken some footage of the same boat a few minutes before with the sun shining on it, as it had broken through the clouds... and there was no color shifting at all.

A few minutes later when the sun was obscurred the shifting began.
 
I've experienced the same problem with the color blue. I was just getting ready to make a post to this forum when I noticed this thread! The first time I noticed it I was shooting a shot of a building that had blue-green shingles. As I panned left, the shingles would "pop" into a darker shade, while everything else stayed the same. Also, the same day, a shot of a man wearing a blue cap exhibited the same problem. It's a bummer that only Standard mode seems unaffected by this problem. The Smooth mode is my favorite. At the risk of sounding cliche, I hope this is a problem that can be solved via firmware.
 
dvbrother said:
At the risk of sounding cliche, I hope this is a problem that can be solved via firmware.
Click to expand...
This may be the kind of thing that actually is solvable by firmware, and the kind of thing that, when encountered, companies usually do attempt to fix.

With any luck the appropriate personnel have been notified, and let's hope that they get right on it and issue a firmware fix.

Until then, the workarounds are:
1) use Standard film mode, or
2) don't use the 14-140 lens, use a manual lens instead.
 
Barry_Green said:
So you're saying that in your experience, it's not just the color of blue, but it's also the brightness of that color?
Click to expand...

Yes.

It was the same boat, same blue. With the sun shining on it, there was no shifting, but a few minutes later, with the sun now obscurred by clouds, the shifting began.
 
You must log in or register to reply here.
Back
Top