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Stephen Mick
10-09-2009, 08:18 AM
Many of the GH1 fans here may have seen my Costa Rica video from a few weeks back. When I put that original cut together, every now and then I would come across a clip that showed what looked like "aperture flicker" or "exposure flicker." Thankfully the flicker wasn't present on key shots, and I was able to cut around it.

After doing some initial research, and consulting with a few others, I chalked up the bad clips to "operator error," thinking either some automatic function had been left on or the variable-ND filter was causing some shifting.

But in the process of putting another recent edit together, I realized the issue that I thought was unique to my setup was, in fact, an issue with the camera itself. After doing some testing, I decided to share it with the GH1 community.

Check out this linků

http://www.proofcreative.com/roxy/gh1_issue.mov

This clip was recorded at 720/60p and changed to 24p in Cinema Tools. Although you can see "refocusing" going on here, the camera itself is in Creative Movie Mode, full manual operation. Whether the focus was set to manual (as most shots were) or partial auto (as this shot was), the results were the same.

You can clearly see the image shifting in exposure from one frame to the next, primarily when the lens is moving up and down with the motion of the boat. At the time, I didn't see this in the viewfinder, but I often shoot focused more on what's going on with my "free" eye than my "shooting" eye.

There are a good many shots like this where the blue sky seems to shift in exposure. All of them were on bright sunny days, where there was a good bit of blue in both the sky and the water.

Again, when I first saw this, I figured there was something I did wrong, some setting I mistakenly used that created this problem. But I shared the footage with another local GH1 shooter, and we tried to recreate the issue with his camera. At first we couldn't seem to get the same effect. Then, when filming a test shot of a woman in a blue shirt, it happened again. The blue tones flickered in exposure, as if the amount or intensity of the color were somehow confusing the camera's brain.

We changed the GH1 from 720/60p to 1080/24p and the issue persisted. We switched shooting "film" modes, and made an interesting discovery: when shooting in some modes, the issue wasn't present, while in others, including even the monochrome/B&W modes, it was easy to see. If I remember correctly, "Standard" mode was clean, but "Smooth" and "Dynamic" showed the shift.

We wondered if maybe this was an issue between the lens and camera, so we removed the kit lens and tried a Nikon 50mm lens on an adapter. No flicker. We tried all the same settings and could not recreate the flicker with the non-kit lens.

So, to sum things up, when using some "film modes" with the GH1 and kit lens, you might experience some "exposure shifting" in the blue tones. Hopefully Panasonic will fix this as part of a firmware update in the future.

I'd be curious to know if any others have seen behavior like this, as now I have seen it on two completely different GH1 cameras.

Adventsam
10-09-2009, 09:53 AM
With CMM, exposure locked still get the flicker, annoying but its there, interestingly one of my most noticeable clips was definately set to dynamic film mode, you are bang on with your findings.

Many thanks, I thought it was me!

Stephen Mick
10-09-2009, 09:55 AM
Are you seeing it specifically in frames with a lot of blue color present? That's the thing that stumped me, is that it only seems to happen when blue is present.

--SM

IanB
10-09-2009, 10:45 AM
Just wanted to say great post, as we find these smaller camera's trying to do so much with the kit lenses, and have all the photo functionality, I think more of these scenario's will pop up.

As the chips get better, more redesign is done for issues like these, I expect gh2 to overcome some of these current issues.

Good news, is that if you limit the processor to just a few items (like capturing etc, and not any communication with the lens, and use a non-standard lens we aren't seeing this shift!)

Great test, we'll see what others find.
IB

BhambuNath
10-09-2009, 11:28 AM
I've never seen any problem with the blue colour - but I was in the vibrant mode during those time.

But there have been times when I've seen problems with the green colour(especially the trees and grass where the small patches have turned into indistinguishable mess).

Stephen Mick
10-09-2009, 11:30 AM
I think the issue with greens (grass and trees) is a detail issue, where the codec turns to "mud." This is something entirely different altogether.

Barry_Green
10-09-2009, 11:54 AM
Yes, the green issue is fairly constant with leaves that are a stop or two down from "optimal" exposure; leaves at proper exposure look fantastic, but the shady areas turn to a smear.

This color issue that Stephen has found is ... mind-boggling. I'm waiting (im)patiently for my GH1 to get back so I can dig into this issue, but -- with it only affecting blue, only happening in certain gamma modes, only happening when using the kit lens, and only happening for a frame or two before it pops back -- that's just about the most bizarre thing I've ever heard of...

Stephen Mick
10-09-2009, 11:59 AM
Needless to say I'm interested to see what you find, Barry, as well as anyone else with a GH1.

ydgmdlu
10-09-2009, 03:58 PM
This helps explain the increased incidence of mud when using the kit lens...

Barry_Green
10-09-2009, 04:01 PM
Y'know what? That may very well be true. A sudden color shift like that could play havoc with the codec...

commanderspike
10-09-2009, 05:09 PM
Are you sure it's happening just on blue tones and not the whole scene, as it looks to me like the video clip you posted is changing in exposure everywhere not just in the sky and water.

A lot of auto-exposure features are enabled with the kit lens including continuous iris. Was intelligent exposure enabled?

Stephen Mick
10-09-2009, 06:17 PM
At first I thought it was the whole scene, but when a friend ran some tests with his camera, only the blue tones were shifting. Which, in the context of my footage, makes sense, as there's so much blue present. And I didn't see the effect at all on any other footage I shot, only shots where blue is a dominant color.

And no, Intelligent Exposure was not enabled.

commanderspike
10-09-2009, 06:24 PM
Very strange. Haven't noticed this myself and have similar footage shot in the sea off Taiwan on a whale sight seeing boat with no blue exposure 'shift'.

No idea what's causing it!

It's curious, but the least of the GH1's image quality wobbles I think. Nothing to worry about too much.

Stephen Mick
10-09-2009, 06:35 PM
Maybe not for you, but let's just say I had some really nice shots ruined by this very issue.

Were you using the kit lens? What were your camera settings at the time?

Until there's a concrete cause and solution, I think it's important to let other GH1 owners know about this, even if you may not think it's a problem.

commanderspike
10-09-2009, 06:58 PM
Maybe not for you, but let's just say I had some really nice shots ruined by this very issue.

Were you using the kit lens? What were your camera settings at the time?

Until there's a concrete cause and solution, I think it's important to let other GH1 owners know about this, even if you may not think it's a problem.

Didn't mean to come across as belittling your work there. Sorry about that.

Yes it's still important to bring this stuff to people's attention and I know first hand how annoying it is to mention a flaw and for others to say it's 'no problem'. Apologies.

Stephen Mick
10-09-2009, 07:03 PM
We're cool, spike. No worries.

Seriously though… Kit lens? Settings? Anything to share?

If this is an issue with the kit lens only, it'd help to know if those who aren't seeing it were using the kit lens or not.

commanderspike
10-09-2009, 07:44 PM
It seems to be totally random and I've never been able to reproduce the problem so I have no advice on this one I'm afraid. I was using the kit lens on the boat, plenty of blue sea, etc. Very similar to where you had the issues. All full auto in iAuto mode and standard film setting. AF and OIS on.

So could well be an image processing issue with some of the film settings.

Isaac_Brody
10-09-2009, 09:01 PM
That's pretty disappointing if you can't overcome this issue with the kit lens. 800 bucks is a pretty steep price for a lens that you can't trust won't mess up your scenes. Now if only Panasonic offered a body only option. The best GH1 footage I've seen has been with other glass than the kit lens. Mud plus color shifting, not good.

Barry_Green
10-10-2009, 07:42 AM
You can overcome it with the kit lens, apparently -- just shoot in the certain gamma curves that don't have the issue.

Stephen Mick
10-10-2009, 08:21 AM
True, Barry. But a much better solution would be for Panasonic to figure out what's causing the problem and fix it via firmware so one could shoot in any gamma they wish.

Barry_Green
10-10-2009, 08:35 AM
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.

Luis Caffesse
10-10-2009, 06:20 PM
If I remember correctly, "Standard" mode was clean, but "Smooth" and "Dynamic" showed the shift.

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.

Luis Caffesse
10-10-2009, 08:15 PM
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).

7003763

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).

MR Fanny
10-10-2009, 09:52 PM
wow...now that's an interesting find that should be made known to panasonic. would really render shots useless.

BhambuNath
10-10-2009, 11:35 PM
This should be fixed in the next firmware update as it produces totally unusable footage...

Stephen Mick
10-11-2009, 06:45 AM
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.

pailes
10-11-2009, 07:50 AM
Question is, can you achieve a certain look through the film modes that cannot be achieved in post with a color grading tool?

Stephen Mick
10-11-2009, 08:16 AM
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.

Nitsuj
10-11-2009, 08:26 AM
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.

Luis Caffesse
10-11-2009, 05:04 PM
so I guess if you know you are going to have blue in your shot with your stock lens then switch to standard.

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.

Barry_Green
10-11-2009, 05:48 PM
wow...now that's an interesting find that should be made known to panasonic. would really render shots useless.
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.

Indyreel
10-11-2009, 06:11 PM
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
10-11-2009, 06:58 PM
Until then, I recommend either using the Standard gamma, or a manual lens, when shooting under those scenarios.

Indyreel
10-11-2009, 07:24 PM
Until then, I recommend either using the Standard gamma, or a manual lens, when shooting under those scenarios.

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.

Barry_Green
10-11-2009, 07:50 PM
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?

dvbrother
10-12-2009, 03:31 PM
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.

commanderspike
10-12-2009, 03:34 PM
So no GH1 blue movies then :)

Barry_Green
10-12-2009, 03:37 PM
At the risk of sounding cliche, I hope this is a problem that can be solved via firmware.
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.

Indyreel
10-12-2009, 06:49 PM
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?

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.

Stephen Mick
10-12-2009, 06:54 PM
Indy-

Any chance you could post a clip for reference?

And thanks for the contribution. The more we know…

SonicStates
10-12-2009, 07:31 PM
I might have some bad news...I was playing around with my rig last night getting used to using the Shoulder mount/FF combination and I noticed something very disturbing in FHD mode...in standard mode AND with a manual lens (Tokina 28-70mm Pro). We have some light blue, purplely curtains in one of our rooms that exhibited this color shift when panning from the white of the wall to the curtains...it was if the computer was too slow and just changed the colour curve once movement had stopped. I looked at the LCD on the cam and thought I must be seeing things because I've been following this thread and using a manual lens in standard film mode. Rushed of the the plasma with card in hand and what do you know? Even my wife said "something is wrong with the curtains"...
I will post some stuff up when I get a chance...I'll try and make it soon.

Indyreel
10-12-2009, 07:37 PM
Indy-

Any chance you could post a clip for reference?

And thanks for the contribution. The more we know…

Hope this helps.

http://www.dvxuser6.com/uploaded/31034/1255401367.wmv

Stephen Mick
10-12-2009, 07:39 PM
There it is!

(Sorry, I shouldn't be so excited about seeing it in other people's footage.)

Park Edwards
10-12-2009, 07:51 PM
shadow correction?

SonicStates
10-12-2009, 07:57 PM
Yeah that's the kind of thing I'm getting as well. Remember though, I'm using Standard mode and a manual lens.

Stephen Mick
10-12-2009, 07:59 PM
Sonic-

Can you share your "Standard" mode settings? Have you changed any of the other parameters in the film mode settings?

commanderspike
10-12-2009, 08:13 PM
Yeah that's the kind of thing I'm getting as well. Remember though, I'm using Standard mode and a manual lens.

Any example video footage? It'd be great to see some on Vimeo of this happening.

SonicStates
10-12-2009, 09:39 PM
Just uploaded a video to vimeo and just waiting in line for conversion. Will add a description when I add the link/embed. Sometimes I look at this and think...it's my eyes but I'll let you be the judges of that....in 28 minutes

SonicStates
10-12-2009, 10:18 PM
Ok here we go. It's kind of hard to tell because of the jerky pull-down inflicted footage (and crappy format) but still to my eyes there was definitely 2 times in the sequence of shots that the blue shift happened. Maybe not as apparent as other footage I have seen but still there.

7038049

Here's the blurb I put on vimeo with settings etc:
Here is a crappy video that I shot while testing my follow focus/shoulder mount. It was shot in FHD (1080i 24p), Standard Film Mode (I might have adjusted after the first clip but the first is definitely standard), Tokina 28-70mm manual lens, a quick white balance was done on a previous evening to fluro lights, shutter was at 1/50 (and hence the banding you might be able to see), no pull down removal (obviously), Contrast set to -2, Sharpening -1, Color can't remember, NR -2.
Just a quite test to show that this blue shift can be experienced in standard mode with a manual lens. Hope this can help the community shed some light on this potentially devastating issue (think skies).
Cheers.

Park Edwards
10-12-2009, 10:50 PM
i definitely saw it on the first and last cut. is your WB on manual, auto, what is your WB? weird stuff..it's like it's taking the blue from the shadow and auto adjusting. anyone know what shadow correction feature does?

ydgmdlu
10-12-2009, 10:56 PM
I see it too.

SonicStates
10-12-2009, 10:56 PM
White balance was set using one of the 2 spaces provided for custom settings (manual then I guess). I used a white card (I think I did) under fluros. I stay away from auto anything as I'm trying to really get proficient with all the settings etc.

Isaac_Brody
10-12-2009, 11:06 PM
Panasonic didn't respond to the firmware requests but it might be worth sending them another mass message with links to these clips. If it isn't just limited to the kit lens then it's a pretty serious issue.

SonicStates
10-13-2009, 01:55 AM
Panasonic didn't respond to the firmware requests but it might be worth sending them another mass message with links to these clips. If it isn't just limited to the kit lens then it's a pretty serious issue.

Count me in.
Anyone else want to test this with non-kit lenses, be my guest. I have another couple that I might try and give a whirl tonight with...Now my OCD kicks in and I spend my time looking for colors (or it seems, shades) that make my camera have a teary!:furious3:

AdrianF
10-13-2009, 03:57 AM
I'm off out shooting in a minute. Got perfect blue skies here, so will test this out with a Four Thirds lens and see what happens.

GMC
10-13-2009, 04:26 AM
I also saw this once on my GH1, when I was in CMM, SHUTTER priority mode, kit lens, smooth film mode (all settings -2). Back then I thought it was probably related to the aperture adjustments, resulting in a kind of "stepping" exposure compensation.

Actually, when in aperture priority mode (with kit lens and smooth film mode), I never saw that again.

I know it doesn't sound consistent with the finding, that also manual lenses are affected. But I would be interested if the above phenomenon can also be seen in aperture priority mode with the kit lens.

best regards

EDIT: forgot to mention that i am always using manual WB, by dialing in the Kelvin temperature

Adventsam
10-13-2009, 07:35 AM
We need to hit Panasonic harder with a threat, that all posters on forums around the globe will be urged to boycott Panasonic GH1 products until this is fixed and give them a 4 week window to either fix it and/or issue a statement recognising the problem; posted by them on the major photo/video sites eg. dvx and dpreview.

Barry_Green
10-13-2009, 08:34 AM
We need to hit Panasonic harder with a threat, that all posters on forums around the globe will be urged to boycott Panasonic GH1 products until this is fixed and give them a 4 week window to either fix it and/or issue a statement recognising the problem; posted by them on the major photo/video sites eg. dvx and dpreview.
Why not try asking nicely first?

Adventsam
10-13-2009, 08:45 AM
Nothing, why not ask them with some urgency for a change, there are plenty of alternatives around. They need to be a bit more responsive this time around, thats all I'm saying.

Stephen Mick
10-13-2009, 10:25 AM
I have to say, at this point, I'm at a loss as to any idea why this is happening. I do still have my camera originals, and I'd be happy to send them along to Panasonic, if they need them.

Jack Daniel Stanley
10-13-2009, 11:02 AM
Thanks for the solid analytical work and trouble shooting Luis and Stephen and SonicStates.
Seems such an obvious issue. Surprised it hasn't come up earlier!

AdrianF
10-13-2009, 02:36 PM
I tried a few test shots while I was out shooting today. I've not come across this problem before and so thought that I wouldn't be able to recreate it. I tried a few tilts up to a blue sky with an OM manual lens in a few film modes and got nothing. I later tried with a ZD 14 45 kit lens from my old e300. I didn't think I had recorded this shift at all until I looked through the footage a second time. At the end of one of the shots, over the last few frames, I got a considerable shift of blues, not a jump in exposure, but a weird shift in the blue channel, just as the OP has demonstrated.

I tried most of the film modes, but this only happened whilst using the Dynamic preset. Shooting with a 1080 25 camera, so it looks like this problem might not be restricted to US/Japanese models.

Park Edwards
10-13-2009, 02:40 PM
I tried a few test shots while I was out shooting today. I've not come across this problem before and so thought that I wouldn't be able to recreate it. I tried a few tilts up to a blue sky with an OM manual lens in a few film modes and got nothing. I later tried with a ZD 14 45 kit lens from my old e300. I didn't think I had recorded this shift at all until I looked through the footage a second time. At the end of one of the shots, over the last few frames, I got a considerable shift of blues, not a jump in exposure, but a weird shift in the blue channel, just as the OP has demonstrated.

I tried most of the film modes, but this only happened whilst using the Dynamic preset. Shooting with a 1080 25 camera, so it looks like this problem might not be restricted to US/Japanese models.

they sky? i'm thinking it has to do with the blue channel being hidden in the shadow is what's causing the camera to compensate for it. dunno. just so far the boat, curtains, have all been under some type of shade.

AdrianF
10-13-2009, 02:47 PM
Shooting a landscape with mountains beyond, about a 50/50 split. Then tilting up to blue sky and down. The weird thing is, the shift didn't happen during the tilt, but just as I bumped the camera to stop the shot. I tried a few attempts in different film settings and didn't get anything.

Jack Daniel Stanley
10-13-2009, 02:51 PM
I had it happen only once, and that was shooting out over a lake with a blue sky.
50% brown/green water 50% sky.

Ben_B
10-13-2009, 02:55 PM
Hmmmm..........I guess the GH1 is not a fan of lakes.

We all know this must be something to do with the kit lens corrections...do you think it has something to do with the chromatic aberration correction? Is it maybe thinking that the place these colors meet is an instance of chromatic aberration and is trying to correct it somehow? Maybe not exactly that but I am sure this must have something to do with chromatic aberration correction...that and it's fun to say.

AdrianF
10-13-2009, 03:10 PM
Ben, I don't think this can be a kit lens thing, as I was shooting with an Olympus lens and Sonic was shooting with a Tokina. Is everyone sure that iExposure was off when this happened. I was switching between off and standard while trying this and the only time it happened was when iEposure was on. Might be no link but worth checking at least.

ydgmdlu
10-13-2009, 03:11 PM
We all know this must be something to do with the kit lens corrections...
We don't know that for sure. Someone's claimed to have reproduced the problem with a manual lens.


do you think it has something to do with the chromatic aberration correction? Is it maybe thinking that the place these colors meet is an instance of chromatic aberration and is trying to correct it somehow? Maybe not exactly that but I am sure this must have something to do with chromatic aberration correction...that and it's fun to say.
Chromatic aberration is color fringing around objects. I gather that it's not easy to correct simply by shifting values in a color channel. To my eyes, what's happening in the footage almost seems like a white balance freak-out.

Stephen Mick
10-13-2009, 03:22 PM
Ben, I don't think this can be a kit lens thing, as I was shooting with an Olympus lens and Sonic was shooting with a Tokina. Is everyone sure that iExposure was off when this happened. I was switching between off and standard while trying this and the only time it happened was when iEposure was on. Might be no link but worth checking at least.

In my case, and with Luis' test footage, iExposure was off.

Indyreel
10-13-2009, 03:42 PM
iEsposure was off on my footage, too.

http://www.dvxuser6.com/uploaded/31034/1255401367.wmv

Has anyone considered why it only shifted on the above link, when the sun was obscured by clouds?

SonicStates
10-13-2009, 06:18 PM
iEsposure was off on my footage, too.



Same here.

I checked the rest of those curtain shots on my plasma tv and it was present in all, to a lesser extent in the between shots maybe but still there, even though you can only really see it on the first and last in the vimeo stuff.

AdrianF
10-14-2009, 10:10 PM
OK, so it looks like the stock lens or iexposure probably aren't the culprits here. Here is the shot where I managed to induce the shift, it happens on the last few frames. Camera is a European model, using an Olympus 14-45 Four Thirds lens. Dynamic mode, 1080 25.

I can't get the embed to work so will just add the link

http://vimeo.com/7070411

Park Edwards
10-15-2009, 09:46 AM
i say any of these types of vidoes forward them along to panasonic.

http://www2.panasonic.com/consumer-electronics/support/Contact-Us.2

Ben_B
10-15-2009, 09:59 AM
Whats the deal with the round lines in the sky on GH1 footage...sky is often kind of segmented looking....I assumed this was the result of color sampling and the codec but now I'm wondering if it's not the kit lens..

Jack Daniel Stanley
10-15-2009, 10:04 AM
are you talking about some kind of banding Ben?

Barry_Green
10-15-2009, 10:11 AM
i say any of these types of vidoes forward them along to panasonic.

http://www2.panasonic.com/consumer-e...t/Contact-Us.2 (http://www2.panasonic.com/consumer-electronics/support/Contact-Us.2)
Agreed. Since I haven't heard back from anyone yet regarding submitting the bugs, do as Car3o said and start sending in complaints. This is a bug and it should be fixed.

commanderspike
10-15-2009, 10:22 AM
Does it also occur when white balance is set to manual on a Kelvin scale?

Stephen Mick
10-15-2009, 10:26 AM
When I saw it in my footage, the WB was set to 5600K, so I would say yes it does.

Ben_B
10-15-2009, 02:16 PM
are you talking about some kind of banding Ben?

Wow I typed a response on a spotty wifi connection and it didn't take :(

Here's what I am noticing. Look at the sky in that clip that was posted on this page. Imagine the image circle. Now look at the sky and you will see little circular bands following the arc of the image circle (roughly.) Not sure if they move with the image (codec issue) or if they are static (sensor banding of some new kind) or are a lens issue, which given the nature of the kit lens could affect the image in either way.

I've noticed it in some of my own footage as well, and it is aggravated on color grading. Will post some screen grabs @ some point.

Ben_B
10-15-2009, 02:27 PM
Wow I typed a response on a spotty wifi connection and it didn't take :(

Here's what I am noticing. Look at the sky in that clip that was posted on this page. Imagine the image circle. Now look at the sky and you will see little circular bands following the arc of the image circle (roughly.) Not sure if they move with the image (codec issue) or if they are static (sensor banding of some new kind) or are a lens issue, which given the nature of the kit lens could affect the image in either way.

I've noticed it in some of my own footage as well, and it is aggravated on color grading. Will post some screen grabs @ some point.

Ok actually it seems to be coming in a circle like if you made circles out from the sun. Here is a screen grab that I crunched on a bit in post and made black and white so you can see what I am talking about....looks like crappy codecness to me, but I don't recall seeing it with non-kit lens stuff. Pretty sure I usually see it @ 14mm.

We may need a name for this...sun-swathing?

Color corrected to show (and less frequent, larger swaths)

http://img48.imageshack.us/img48/1170/screenshot20091015at223.png

Original (more frequent, smaller swaths)

http://img48.imageshack.us/img48/8985/screenshot20091015at222.png

I can change color correction sliders (mainly mids) to change the frequency of the swaths, the size, and the proximity to the sun (right side)

SpecialEdFX
10-15-2009, 02:28 PM
AH HA! I noticed this shooting plants and an old hotel up in the Hudson Valley. Medium shot of leaves, the blue/green midtones were hopping between color values. I have everything set to manual, using Vivid color.... And come to think of it, my Nikon lenses haven't given me this guff

SpecialEdFX
10-15-2009, 02:32 PM
Hey Ben! What you have there is gradient banding. It's an old problem when using 8 bit RGB. Watch the GFX on many commercials in high def and you'll see the same junk. For the most part, our eyes are way better than our displays and it becomes very prevalent (like in your BandW photo) when you crush the dynamic range with contrast. The best way to nuke this fractillian order is with a hint of noise. It will disrupt the uniformity of the banding just enough to soften the issue

Ben_B
10-15-2009, 02:33 PM
That's interesting cause I've been shooting most of this at contrast -2...hmmm.

This aggravated by 4:2:0?

Definetly noticed it when trying to do some HDR stuff.

Martti Ekstrand
10-15-2009, 02:50 PM
That's 8 bit colour space showing it's limitations. Same thing happens in After Effects / Photoshop on generated gradients with a discreet colour change if working in 8 bit mode. You can apply Smart Blur and/or grain it to break the banding.

Ben_B
10-15-2009, 02:52 PM
That's 8 bit colour space showing it's limitations. Same thing happens in After Effects / Photoshop on generated gradients with a discreet colour change if working in 8 bit mode. You can apply Smart Blur and/or grain it to break the banding.

Good to know. Working in 10-bit in post (important for lots of color correction stuff) but obviously that doesn't change what's already been recorded. I'll try some of those tricks if it blows a critical shot....also I think I may have some color shift for you guys, stand-by.

Martti Ekstrand
10-15-2009, 03:54 PM
I did the post on my commercial in After Effects with 16 bit mode, helps when pushing colours around to have way more discreet steps :)
However I always render out to 8 bit myself in the end as that's how it is broadcast - better to see and deal with the limited colour space before it's on the air and banding has snuck in at some unexpected cut.
Come to think of it - these colour shifts could be that only Standard mode stays within the 8 bit colour table of the AVCHD format and therefore it does some flipping between two values when a colour hue falls between the cracks. Haven't seen the shifts myself but I haven't done much skies yet. Oh wait, I did see some shifting once when I was pushing the battery to it's limit - ie some minutes before it packed in and camera stopped recording and shutdown.

Ben_B
10-15-2009, 03:58 PM
Think we should then be shooting in Smooth mode?

AdrianF
10-15-2009, 11:51 PM
When I saw it in my footage, the WB was set to 5600K, so I would say yes it does.
Same here on the clip I posted.

@ Ben, the banding does occur on other lenses apart from the kit lens, but as others have pointed out, it can be rectified in post. It's certainly not unique to the GH1, but can be a pain when it does occur.

Stephen Mick
10-16-2009, 06:24 PM
Think we should then be shooting in Smooth mode?


The only modes that did not produce the "color shifting" in my testing were Standard and Standard B&W. You may or may not get them in Smooth mode, but Luis and I certainly did.

Luis Caffesse
10-18-2009, 02:58 PM
i say any of these types of vidoes forward them along to panasonic.

http://www2.panasonic.com/consumer-e...t/Contact-Us.2 (http://www2.panasonic.com/consumer-electronics/support/Contact-Us.2)
Agreed. Since I haven't heard back from anyone yet regarding submitting the bugs, do as Car3o said and start sending in complaints. This is a bug and it should be fixed.


Seeing as we haven't heard anything in response - just wanted to urge all the GH1 owners to drop Panasonic a line about this issue if you haven't already.
Hopefully if enough members make them aware of this problem they will respond in some way.

Ben_B
10-19-2009, 08:33 AM
I am totally shooting standard from now on!

I found my footage looked weaker (IMO) in smooth mode...more barf from the codec everywhere.

pailes
10-19-2009, 11:31 AM
I am totally shooting standard from now on!

I found my footage looked weaker (IMO) in smooth mode...more barf from the codec everywhere.
I prefer shooting in the most neutral way and creating a certain look afterwards in post. If you decide to create a certain look right in the camera you will have a hard time getting it to look differently in post.

So filming in standard mode is definitely not a bad thing, it really depends on what your workflow is.

Ben_B
10-19-2009, 01:56 PM
Yeah that's why I was shooting standard but then I moved to smooth cause it looked pretty nice but now I'm going back to standard.

Jason Adams
10-20-2009, 07:07 PM
Great work guys. I best Panny's consumer camera division is not use to getting such detailed and professional scrutiny of their camera bugs from working pros. Hopefully they respond soon. Guessing jane soccer mom would have never caught this bug, but DVXuser pros did.

Another reason why if you work in the industry you need to be on this site.

Luis Caffesse
10-20-2009, 11:21 PM
I bet Panny's consumer camera division is not use to getting such detailed and professional scrutiny of their camera bugs from working pros.

I guess not - honestly I'm a bit shocked that there has been no reponse from Panasonic on this at all.

At this point I don't think there will be - this may simply wind up being one of those issues they let go and then quietly fix in the next generation of camera.

I hope that's not the case - but the deafening silence isn't increasing my faith at all.

Stephen Mick
10-20-2009, 11:23 PM
Agreed. There's a work-around, but when that work-around is not using 6 of the 8 or so camera "film modes," that's not acceptable.

Luis Caffesse
10-20-2009, 11:26 PM
Agreed. There's a work-around, but when that work-around is not using 6 of the 8 or so camera "film modes," that's not acceptable.

You're being generous - one of the two modes left is a B&W mode.
Which really only leaves one (Standard).

Barry_Green
10-21-2009, 09:55 AM
I guess not - honestly I'm a bit shocked that there has been no reponse from Panasonic on this at all.
Okay, but let's put it in perspective -- how many responses do JVC, Sony, Canon, or any of the other companies give? They don't communicate to the end customer at all. Just one day a firmware update pops up.

I expect that this will be the same situation, one day it will get fixed.


I hope that's not the case - but the deafening silence isn't increasing my faith at all.
Deafening silence is the standard for all these companies. Canon never speaks to the end user in either consumer or professional products (except for the unbelievably rare recent announcement about the addition of a forthcoming firmware update for 5DMkII/24p). JVC never talks to the end customer about addressing any issues or fixing anything, in either consumer or pro. Sony never speaks to the end consumer about fixing any issue, either consumer or pro. And Panasonic Consumer never speaks to the end consumer about fixing any issue, either consumer or pro. And then one day a firmware update pops up on their site.

We've been spoiled by Panasonic Broadcast communicating back to us, and by Red communicating back to us. But they're the only ones who do. For everyone else, "deafening silence" is the normal modus operandi.

Doesn't mean it won't get fixed; frankly I'd be shocked if it doesn't. This is exactly the kind of thing a firmware update is designed to address.

Luis Caffesse
10-21-2009, 10:17 AM
Okay, but let's put it in perspective -- how many responses do JVC, Sony, Canon, or any of the other companies give? They don't communicate to the end customer at all. Just one day a firmware update pops up.

Fair enough.

Though I didn't mean to imply that Panasonic was acting any differently than any other company - and were it any other company I would have said the same thing.
Yes, we have gotten spoiled by Panasonic Broadcast and by Red - because it's the way things probably 'should' be done in regards to communication (at least in instances of 'bugs' of this nature).

A 'bug' that affects the core function of a product is something that any company would be better off dealing with sooner rather than later. And the longer the lag between the discovery of an issue and a reaction from a company, the more faith in that product gets lost by the end users.

That's all I was saying - nothing groundbreaking.
You're right, though - noncommunication is pretty much the norm across the board.

Barry_Green
10-21-2009, 10:32 AM
Right, point being -- who knows if Panasonic is even aware of it yet? They may have just heard about it today, for all we know. I would love to have a dedicated consumer presence here, like we have with Jan for broadcast, someone that we could rely on to relay the information to the factory. I don't know who that might be. Maybe I'll have to go to PMA or something and meet someone and drag 'em over here, because ... well, we've got Jan, we've got Rick Haywood from NZ, we've got Rob Myers from Australia, we have at least three territories of Panasonic Broadcast that monitor our forum and who we have easy access to. But in consumer, nada so far.

If we had a rep here, we'd at least know we were heard, and I'm sure that'd make a big difference... but then again, that representative would probably be prohibited from talking about forthcoming fixes or unreleased products, so -- the net effect might not be any change at all...

Ben_B
10-21-2009, 11:42 AM
But at least we'd know they're listening.