Color/Exposure Shift on GH2
 

Anybody else having problems exposing for GH2 because once you hit record, the exposure and white balance shifts?

Apparently the histogram shifts to the right, and the camera would be getting a greener and darker tint.

Solutions please.

How are you setting your exposure and color balance ?

I shoot with everything on manual, and I set my color balance via degrees Kelvin. I haven't experienced any problems with this.

i just wana say that you not only one with this problem. But still i cant help u now. If ill find something, i will share with u.

Same with my GH2. The more so: the higher ISO - the bigger shift towards green. Probably some bug in a firmware, as it seems it happens only on LCD or LVF, because when I play it on my laptop it looks fine.

If you're talking about what I brought up in another post, it is referenced in the manual but I can't find it.

When shooting a f/4.0 this morning the screen looked fine...but hit record and it appeared dark. I took a photo and it was dark also. Not sure what this is about.

My first reaction is "How do I work in a run and gun situation with this issue?".

Jeff, I just don't rely on what I see after pressing record button, but what I see BEFORE that. At least it works for me. I was trying to play with some presets, like "constant preview" or "My color profile" etc. but none worked out. As far as I know - no one has found solution as yet, therefore people just live with it. I must admit I am already quite used to my screen (LCD and LVF) going darker and greenish-tinted after I hit the button...

It is also true that after you start to record, the histogram shifts a bit to the right. I have not measured yet if it really reflects the change in video being recorded, or it is only strange histogram window behavior. Just in case I keep my eye to the lights - to not overburn the lights.

User Manual is rather useless, It is written in very awkward manner, so most of what I have learned so far is just the result of "hit and miss" :) However I find GH2 to be reliable when I record in manual mode, using mostly Cinema or Smooth presets. Both render colors similar, but Cinema handles the lights better, while Smooth is better if you care about blacks/shadows details.

Hope it helps.

PS
Similar thread
http://www.dvxuser.com/V6/showthread...ht=color+shift

Yes, I admit in Cinema mode, from the few minutes I've had with the camera, does seem to work well.

Conditions change while shooting, lighting changes, people move into areas with different lighting conditions, what do we do when following someone, stop the camera, check the picture, reset it, then start back up? In the meantime our subject has moved and we've either lost them or we have to catch up with them? This is particularly troubling for outdoor shoots following a bridal party around outdoors in the park, etc.

This is not good for wedding videography. One minute after the first dance begins, the lights are then lowered, so during the first dance I stop the camera, check my settings, and restart?

Maybe I don't have full understanding, but at first blush it sounds like a nightmare.

I can't tell you how many reviews I read, posts I read, before purchasing the camera. This is the first I've heard of this. Live view should mean as it is being recorded.

I'm not sure if manual control of shutter speed, exposure are available during 24p cinema mode.

The manual should be divided into two main sections, Photo and Video. I find myself going back and forth from front to back with these incomplete explanations and it is crazy.

For example, does the camera have auto gain for the audio when in some modes? I suspect in iauto it might, but it is not clear.

Jeff, I do agree - color shift on displays may be a bad issue for your type of work. Before or after pressing Record button - it should stay all the way the same. But do you change any settings during action/recording? I doubt it, so you better stay with what you see before recording starts, otherwise the the LCD screen/LVF may cheat you.

I am not sure whether GH2 is "more WYSIWYG" before or after your recording starts (..?) In my opinion it is more WYSIWYG before you start recording, because when I playback my footage on a PC, it never goes as dark/green as LCD/LVF shows it during recording. I was also trying to adjust/calibrate GH2 displays (LCD/LVF) using Monitor presets (Menu>Setup>2nd page), so it would match reality and colors I see after pressing Record, but then you get GH2 displays too bright and too much magenta tinted. I was not able to calibrate LCD/LVF so It would work well in both cases - before recording starts and after it has started. So I rely on what I see BEFORE (monitoring eventual clipping of lights) and it works fine to me. Anyway, I hope it will be fixed soon by Panasonic on FW upgrade, as this is important, and it is not a feature, but what the Live View really means. So far we have to live with it...

The manual is possibly the most disjointed manual I've had the displeasure to read. My one and only shoot with the camera so far has been my manual. Just got the camera Friday.

Using Cinema preset, I did not experience any shift and the footage looks as much as it did in the LCD. One question: in manual mode I couldn't get control over the aperture while shooting. Shutter yes, ISO yes, but I could only set the aperture before hitting record. Is this correct?

As much as it looked after you've pressed the record button..? Didn't you observe any change before and after hitting the red button? William - take a closer look again ;) And observe how the histogram also shifts to the right...

PS
You can change aperture while recording, but you have to press/click the rear dial first as it switches you between shutter and aperture (in Exposure mode = M). However I wasn't able to change ISO during recording. How did you get it???

Ok Waldi, or anyone, can you explain, if you know, what is the Exposure compensation thing? It seems to be some kind of exposure setting, but I'm not sure how it takes the place of setting the exposure, or what.

Where did you get it, in User Manual? I can't see it in a menu...

But if you talk about the small thing at the bottom of the screen, next to ISO value - it is a simply indicator showing your current exposure correction, in EV steps (EV is a photographic term). So it shows you how far (how many EV steps) u are from "correct" exposure - in relation to what GH2 thinks is correct exposure... When your exposure is "correct" (I mean EV = 0) the histogram will confirm it turning into white, instead of orange. This indicator shows a range from -3EV steps through 0 to +3EV steps.

It might apply only to photos, I don't know. It's on page 132 of my manual...near the bottom. it is referenced in other sections of the manual also, very confusing.

I've seen it on my screen a time for two, but forget when and where it happened.

It is also reference here in the second image from top, lower right. http://dpreview.com/previews/panasonicdmcgh2/page3.asp

No Jeff, it apply to both: photos and videos. It helps you find out how far you are from "correct" exposure. One EV step is the same amount of light like one F-stop. So when you set up your camera for shooting video, first of all you observe how the image/scene looks on LCD or LVF, but observing this "exposure compensation" indicator helps a lot as well.

Thanks Waldi. I'm going to play with the camera tonite.

Jeff - you helped me, I would be happy to help you. Feel free to ask me any question.
And maybe have a look at this:

Very good, thanks Waldi. I'm going to watch this video this evening while I go step by step with him....but I can't really work with the EVF very well, my eyesight isn't so good for that, but I'm going to see what I can do!

It does not matter if one uses EVF or LCD, they are identical and work both the same way.
PS
Not everything will work as on the video above (unless you attach a third party, MF legacy lens). However manual exposure correction and shutter/aperture will work the same.

OK, I see. I am anxious for this evening when I can follow the video and a learn the step by step method of working with the camera, very good video...thanks so much for posting it.

My pleasure. A guy in a video above is shooting pictures, but it applies to motion mode too.

When i first had my GH2 colour change happened slightly but since setting my personal settings IE smooth
-1 sharpness -1 colour -1 etc it has not happened

I've noticed that in a dim light or high iso - the color shift is much more visible. In a good light I almost see no difference.

For me it is inconvenient to use it by touching LCD screen, so I use a physical rear dial instead. If manual mode is set (Menu/Motion picture/Exposure mode=M) the rear dial brings you to the aperture and shutter control. Push/click the rear dial and you switch from shutter control to aperture control. Do it again and you are back on shutter. Turning the rear dial to left or right changes the shutter speed or aperture. Observe the Exposure indicator (bottom middle of LCD) as it tells you how is your exposure at the moment, at a chosen shutter/aperture (and iso) combination. If underexposed you will see something like this:
"-3||||||0"
or if overexposed:
"0||....+3"

When your exposure is correct (due to what GH2 thinks is "correct"), exp. indicator turns into a little square diagonally divided, with +/-. Also the histogram turns white (instead of orange). So it is easy to get correct exposure by choosing any shutter/aperture that way. But to change iso - you must click the iso button (up arrow).

PS. I have been a long time photographer and I've been confused when I started to deal with videography, because of slightly different names and terms. So if you have no photography background please note: the exposure in photography is based on EV values (GH2 follows the same way). And 1EV value is like one F-stop of aperture (or a shutter). When you close aperture by 1 stop - you cut out 1EV of light. When you change shutter speed from 1/120 to 1/60 - you add 1EV more of light. In video terminology when amount of brightness is concerned the 1EV step is similar to about 4.5 Gain (approx.). And 100iso is 1EV less than 200iso, 2EV less than 400iso, 3EV less than 800iso etc. So respectively: when 100iso is like about 0 Gain so 800iso is like about +13.5 Gain (as 3EV = 3x 4.5 Gain more). And so on...

Hope it helps.

I was looking at that evf video and as he change the shutter or iso, the evf does not change in brightness, is this how this camera supposed to work? if so this is crazy because I was about to get one but if the lcd or evf does not give real time feed back, there is no way I'm can use it.

Khoi - you need to set first: Menu/CUSTOM/page4/CONSTANT PREVIEW = ON to be able to see how it affects an image in a picture mode. In movie mode you see it anyway.

Ok thanks, I didn't think that the camera could be so popular if it didn't have realtime feedback.

Here is a quick test I shot w/ my iPhone4, pay close attention to the 1st 1/2 second and the histogram

http://dl.dropbox.com/u/3078363/willis/GH2-Shift.MOV

Willis - your screen looks quite good, it doesn't go green as much as mine, yours go just a bit darker after you pressed Record. What were your presets? Color profile like Cinema, Standard or what? Was "constant preview" set to ON?

Re: Color/Exposure Shift on GH2
 

yes it was set to on, my image settings were on SMOOTH, everything on -2, except for noise reduction.

I went to SAMY's CAMERAS the other day to test out their GH2 over there, their GH2's histogram (while recording) still covers the very left portion, even though it does darken the image while recording... however on my histogram, it's completely empty on the very left.

Re: Color/Exposure Shift on GH2
 

So it seems some GH2 do have "shift histogram" issue, and some do not..? That's very strange!

Mine histogram jumps to the right (if I start recording), leaving some empty space on a very left, but image becomes darker on LCD... However, despite of that, the exposure is just right - I mean as right as I want it to be. The highlights blink on LCD exactly at the same point where they start to be clipped on a footage. At least one feature we can rely on :)

Re: Color/Exposure Shift on GH2
 

Just wondering if any progress had been made on this. I posted on another site but didn't get a satisfactory answer.

Recalibrating WB hues doesn't seem to be an option as in brighter lighting the color doesn't seem to shift.

And I've tried turning on "Constant Preview" and have set color to "Custom". While it worked for some it didn't do anything for me ...

Re: Color/Exposure Shift on GH2
 

I just read this post and immediately went to my GH2. Took a still image. Then switched it over to video. Comparing the icons side by side on the viewfinder, the video definitely tends toward green.
Reviewing both supports that finding.
Easily fixed in Post, but still an odd and off-putting thing.

Re: Color/Exposure Shift on GH2
 

Yes a bit disconcerting. Any suggestions for an in-camera fix? My GH13 doesn't do this so never had to think about it before ...

Re: Color/Exposure Shift on GH2
 

Not sure if this helps, but I seem to find more consistency with m/4/3 lenses and Olympus lenses. A Tamron I had gave me fits for colors, and the Sigmas are much better, but still weird if I'm not vigilant.

With the 12mm F/2.0 and Olympus 12-60mm, I see very consistent results. The 20mm F/1.7 can unexpectedly give funny color results, but normally is very good for consistency, but can also weird out on me at times.

The Canon FD 50mm F/1.4 and 135 f/2.5 are almost universally difficult for me to color balance. Often the footage looks completely different on the screen than it does when played back, and I still cannot figure the why of that. I have given up using Canon lenses, it's too confusing for me with multiple cameras.

The nature of video and photos are different, and I think lighting conditions in one situation can produce consistent colors, and in other circumstances the camera will handle colors differently for video and photo. Not being a technical person, I don't know the why, but as I learn the gear I learn what works, and I just deal with it. I also stick with M4/3 lenses now mostly, and this is a huge help.