Low Light Streaks - Is my camera faulty?

Not to belittle the problem, but the streaks are MUCH more visible when you look at the video frame-by-frame. When playing on my TV (usually shot in the 720p AVCHD) the streaks are much less obvious and unless I pointed them out and made someone like my mom look carefully she probably wouldn't notice them. In extreme cases this isn't true, but in the shot above, based on my experiences it probably is. This may not be acceptable for professional use, but from a consumer standpoint (mom taking a video little Joe at the soccer game) it probably is. There is no way engineers at Panasonic can't have seen this in their development.

I think this should go in the firmware request to Panasonic. They obviously treat this as a consumer level cam where they can get away with these blemishes. A concerted (POLITE) effort may be needed to convince them that there is significant professional interest in the camera too *IF* they can fix some of these issues.

Just my $0.02.
 
AdrianF said:
That looks pretty severe. How about giving us some of your settings?
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I've yet to see banding on properly exposed footage. Closing up the aperature and putting the frame rate through the roof is bound to bring out banding especially at high ISOs.

If you have a fast Canon FD lens or something and don't want to lose the nice shallow DOF at F1.4 get a ND filter on there and it'll be fine.

Keep the shutter speed below 1/100, preferably 1/60 in 720p or 1/30 in 1080 and it'll look fine.

Has anyone got banding on footage shot at 1/30, not under exposed?
 
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Following up on my post #169 - ok, I can confirm that the "burn-in" theory (as roposed by Commanderspike) works - at least for me. Images are cleaner - there still is some streaking, but not so pronounced/obvious, and now in -1 exposure, I can hardly see it. at -2, it is very faint and more organic. Of course at -3 it's not there, as the image is very dark.

So I repeat my procedure - let the camera run 8 to 12 hours a day. Point it at some blank wall - turn off lcd & viewfinder, let it run off the mains,, no need to hit the REC button. Keep the exposure low - my settings were 1600 ISO, aperture 4 (wide open) and shutter was whatever speed where the banding/streaking was most obvious.

I wrote to Panasonic (service center in Singapore) and attached a video clip (that showed the streaking) as well. They replied that the CMOS sensor was performing within spec! Whatever it is, they are aware of the problem.

Again, thank you everybody for your feedback on this
 
jamesjjs said:
Ok - So I mounted the Gh1 on the tripod, 1600 ISO, 30fps and pointed it out the window into the night scenery. For eight hours. I used the mains, left the camera on, closed the lcd flip out screen. And that's it - no need to press "record" - now I get VISIBLY reduced banding - in the order of like 60-70 percent for the lower ISOs, but for 1600 to 1000 ISO, I'd say about 40 percent.
Of course, your mileage may vary - and thank you all so much for sharing - I hope this helps you.

Tonight I will do this again just before bed... and report back if any improvement
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What's the reason for pointing it at the night sky? Why wouldn't you just leave the cap on and leave the camera on?
 
Admactinium - I just acted on a hunch - that's all. You can try with the lens cap on. If that does not work, then you've just wasted 8 -12 hours!! I read somewhere (Kholi I think) that if you keep the camera underexposed for a period, the streaking minimizes. And, after reading all the posts of people whose streaking problem disappeared after a couple of days, I thought it would make sense to let the sensor shoot something.

Frankly, I was pissed as hell as OPHERBA (who returned the camera) and I agree with him that it all seems like voodoo. I have shot 5 days straight, 8-12 hours, plus hundreds of clips in between, testing all the settings. I got the camera since July 1st, and now, July 20 (almost 3 weeks later) things are ok.

Do you know how much time/energy I've invested in this damn thing?! Barry Green said he would not want to test all the film mode settings - guess what? I did. Just about every setting I could think of - I tried.

Finally - the streaking levels are within reason.
 
jamesjjs said:
Do you know how much time/energy I've invested in this damn thing?! Barry Green said he would not want to test all the film mode settings - guess what? I did. Just about every setting I could think of - I tried.

Finally - the streaking levels are within reason.
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I for one appreciate the effort. If it works I'll have you to thank. People have advocated proper exposure procedures and they're right. It was never my intention to underexpose the principals in a shot but background and peripheral images is what I'm concerned about. I want low light levels for those areas. I'm trying to avoid larger areas of light colored flat surfaces but sometimes that's just not possible so anything that will lessen these streaks will be welcomed by me.
 
jamesjjs said:
Admactinium - I just acted on a hunch - that's all. You can try with the lens cap on. If that does not work, then you've just wasted 8 -12 hours!! I read somewhere (Kholi I think) that if you keep the camera underexposed for a period, the streaking minimizes. And, after reading all the posts of people whose streaking problem disappeared after a couple of days, I thought it would make sense to let the sensor shoot something.

Frankly, I was pissed as hell as OPHERBA (who returned the camera) and I agree with him that it all seems like voodoo. I have shot 5 days straight, 8-12 hours, plus hundreds of clips in between, testing all the settings. I got the camera since July 1st, and now, July 20 (almost 3 weeks later) things are ok.

Do you know how much time/energy I've invested in this damn thing?! Barry Green said he would not want to test all the film mode settings - guess what? I did. Just about every setting I could think of - I tried.

Finally - the streaking levels are within reason.
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I didn't mean to mock what you were doing. On the contrary I'm just trying to figure out exactly what you're doing so I can do it as well. My camera shuts itself off after a while. So you're pointing it at something dark at night, no LCD, no EVF and it's not recording. What exactly is it doing?
 
Guys, thank for the tip, I hope I will not have to use it on the next one I get... :)

I posted a clip with the vertical lines problem in a "normal" exposed method here: http://www.vimeo.com/5656539
To really see the problem you better download the (large) file and watch it on a big screen since Vimeo compression tends to "smooth" things up.

Thanks

Johnnie
 
Admactanium - no, no - not at all! I did not think you were mocking me at all - yeah, guess when I re-read my post it sounded like I was angry or something... it's that I don't want ANYONE to waste their life doing stupid things like I did.

It's no fun testing/troubleshooting and working with all kinds of uncertainty - I was hoping Panasonic would acknowledge the problem, even after showing them my clip. The reply I got back was "this is within the CMOS spec."

I've read how people have been waiting for months - I bet some of them are going to get streaking problems as bad if not worse than mine. At least they have some idea of how to minimize the streaking.
 
I am trying to figure out what the best way to 'burn in' your GH1's CMOS sensor. We need a better understanding because it certainly has potential, it seems.

By the way, what is the Pixel Refresh for in the menus? A detailed technical description of that might reveal how the CMOS sensor works and therefore suggest a more scientific explanation for the burn in theory. I think Pixel Refresh removes 'stuck' or 'hot' pixels doesn't it? Why do they occur?

The fixed pattern noise of CMOS sensors fading or changing over time. Hmmm. Could it be that when the sensor heats up, very small components slot into place better, after being more or less slightly skewed by manufacturing and transit?

Or is it something related to the CMOS technology itself, a characteristic?
 
jamesjjs said:
Following up on my post #169 - ok, I can confirm that the "burn-in" theory (as roposed by Commanderspike) works - at least for me. Images are cleaner - there still is some streaking, but not so pronounced/obvious, and now in -1 exposure, I can hardly see it. at -2, it is very faint and more organic. Of course at -3 it's not there, as the image is very dark.
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Fascinating.
I'll give it a go... when I find where I put my mains cable that is!

Did you shoot some tests in identical situations before and after the burn-in? Be really interesting to see the results. Perhaps we could do a "pepsi challenge". Show us the two photos and see if we can work out which was which. Or is the difference totally obvious?

This is really positive news so thanks for sharing.
 
PappasArts said:
If that's the case, it would be most likely a coating of some type that the heat was dissolving or tempering.....
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I concur with this. If it was any kind of interference, either electromagnetical or just our spirit auras it should move or rather flicker like crazy but it is fixed - at least on my GH1. Also the pattern is rather organic, interferences should be more pixely. Probably will the new ones in later shipments exhibit less of this as Panasonic fine-tunes the manufacturing process of the sensors. If it doesn't diminish in a couple of days or is really visible even at low ISO values on your particular GH1 I think you should go back to the reseller and demand to have it replaced.

I'm also one of those who saw it in the beginning but hardly at all now. It's faintly visible on a few places in 'Closing Time' which was shoot roughly 7 hours after I got mine.
 
First, my apologies for no before and after shots but jamesjjs' procedure is working for me. 18+ hours straight pointed at an underexposed white folder and it is visibly lessened. The streaks are still there, for sure, but visibly lessened. As we all know it looks worse in stand by mode but when I press record I can't believe the difference. A few of us were going down this road but jamesjjs really stuck with it. Dude, if your out there, I soooo owe you a beer.
 
You might want to try pointing the camera at something moving or at something that changes in brightness. I don't know for sure if this will speed up the process but I mention this because the streaking on my GH1 had faded after about 6 to 7 hours of shooting. All my test shoots were in a wide variety of lighting conditions including pointing it at high contrast moving tree branches and leaves (I was trying to break the codec). Especially with a blue sky background - thats a lot of info to put thru the sensor.
 
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Nighthawk - glad it worked for you!

Nathankw - the difference is like night and day. I'm too lazy to post pics!

J Davies - I thought about shooting moving objects and different lighting, etc... but that was waaayyy too much work. So, one day I thought, why not just let it run through the night while I sleep? If it breaks, then I send it to Panny since its under warranty! In fact, better if it breaks - at least I'll have a new sensor.

Martti / Pappas / Commanderstrike - yeah, I get the same feeling like it's some king of residue leftover. It really looked like someone ran a vertical stroke down the sensor with a fat paintbrush dipped in oil.

Again, all of you have been very inspiring. While I may have stuck through this process, I gained insight through everybodys' reports on this issue.

Cheers!
 
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