Low Light Streaks - Is my camera faulty?

But seriously, the lack of live monitoring is quite inconvenient. And so is the lack of a headphone jack.
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Were you using the camera for sound (and did you get good results if so), or do you mean that the lack of a headphone jack is a inconvenience in principle?
 
We were running usually four channels (one boom, and three hated and dreadful lavalieres... I hate and dread lavalieres!) So we used a Beachtek on the camera, and a Zoom as a dual-system recorder.

So yes, monitoring audio off the Zoom was easy, but of course there was no picture to back it up...

The lack of a headphone jack is, in my opinion, a silly oversight, but then again this is video grafted into what is essentially a still camera, so I guess I should just be happy that we got the far-more-important mic input jack...
 
Although I instinctively doubt whether video monitoring could be added by firmware, perhaps audio monitoring from the composite cable at line level might be possible one day, allowing connection of a small headphone amp.
 
Barry_Green said:
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So -- the rule stands -- if you underexpose by about 2.5 stops, you're going to see banding. Nothing you can do about it. So don't let the main focus of your image be underexposed by 2.5 stops! If it happens in the background, then yes it'll be streaky in the background.

Banding shows up under two requirements: a) the area must be underexposed by at least 2 stops, usually 2.5 stops or more, and b) it has to be largely devoid of detail (meaning a flat surface, skin, paper, a wall, etc). Those are the scenarios under which it will happen, and it will *always* happen, no matter what your ISO setting.
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Thanks Barry for no beating about the bush. You just wrapped it up. Surely, the problem will still be there, if you have a quite contrasty close up shot (like my sample pic) where one side of the face is well exposed and the other side underexposed. If you overexpose this scene you run the risk to lose the details on one side. Anyway, you´re right, a combination of slightly overexposing or properly on set and bringing it down in post could do the trick...
 
Thanks for all the advice.
If nothing else, it's confirmed that I'm not the only one seeing this!!!

Unfortunately it still seems like some things are unclear.

It's still not clear whether all cameras suffer to the same degree or whether people are just using it differently.

It's also not clear whether the burn in theory is real or just down to people learning to use their cameras better.

I think it would really help if we could clarify these issues. Lets try to devise a test so that everyone could take similar footage and we can compare. If we all use the same settings and the kit lens, set up lighting on a flat surface so that we get correct exposure (according to the camera) at say 50th of a second, fully open, ISO 400. Then change to 200th second so we're 2 stops under, and see what we get.

Would this work? Lets try to get a foolproof protocol and then get people to upload photos.

Also, does anyone have any controlled test before and after burning in that could prove that it really makes a difference?
 
I'm starting to think that dynamic range has something to do with it. I took some footage at our local railway station last night from a bridge over the tracks. The well-lit station came out bright and clear. The darker streets and car parks around it showed up pretty well too with no obvious noise issues, but the unlit areas just came out black. I've seen the phrase "crushed blacks" used here, and I guess that's what it means - something that almost dark is rendered as black, rather than as noise.

In audio (more my field), we'd call that a noise gate - in the absence of a signal above a certain level, then the audio is muted altogether, which gives the impression of no noise in the signal chain.

So with the GH1, noise and banding will probably show more if there's not much dynamic range (between dark and light) in the scene (low contrast I suppose I'm saying), and if it's generally underlit (or underexposed), so that nothing much gets crushed to black relative to the bright parts (because there aren't any), and the noise shows up more in the form of banding.

I'm not expressing that very well but hopefully it makes some kind of sense.
 
Sure, there would be lots of benefits -- not the least of which would be the ability to monitor audio, and remotely monitor video during recording! Plus power zoom, and 720/24p, and certainly mud-free better compression, and the ability to attach XLR microphones, and having a sweet waveform monitor and zebras for exposure...

... but you'd be giving up the shallow DOF and interchangeable lenses.

So you'd have to decide whether those tradeoffs make sense to you for your shooting circumstances.
 
Argh! I just got my camera, and the FPN is unbearable. It's not just at high ISOs, it's on EVERYTHING. It's just easier to see on flat colors.

Should I sent this unit in for repair or replacement? It looks like someone cleaned the sensor with windex. Sure, outside in super bright daylight, you can't see the bands, but on just about anything with a flat solid color, it's band city. ISO 100, 200, 400 - doesn't matter. It looks like the German picture earlier in the thread.

720 mode is a little better than 1080, but still terrible. Tried the burn in thing for 12 hours - no difference.

I'm really wanting to love this camera, but the noise is getting too much in the way.

Advice anyone?
 
turn eco modus off (system settings), close the display and let the camera be on for at least one night in creative movie mode.
check it out in the morning, should be better...
 
I'm still of the opinion that it's to do with how large a proportion of the image is underexposed. I recorded some video of some domestic scenes last night in a room from which other rooms lead off - they were more or less in darkness. No banding could be seen in those doorways when the majority of the image involved the medium-bright room I was recording in. But at one point I took a closeup of someone standing in the doorway to one of those darkened rooms, and the banding on the almost-dark walls within was pretty obvious. The correctly-exposed subject of the image at that point probably only occupied say 15% of the shot. The same walls in wider views, where a greater proportion of the image was well exposed, were bandless and simply dark. I guess the histogram would probably show what was going on. My point is that it happens in a certain kind of shot, and maybe some people's shooting style happens to gravitate towards that kind of shot and so they perceive a bigger problem. I would suggest some test shots with the histogram displayed, and try to work out what does and what does not cause the banding to become unacceptable. Then avoid that kind of shot - or don't use the GH1.
 
Hello, first post here, hoping I'm not going to put my feet in my mouth!

As someone has already posted in this thread, digital signal processing can achieve amazing things when it comes to repeating patterns like these streaks.

Getting rid of the FPN is actually trivial, given the right tools.

At my previous work place, a collegue had written a FFT (Fast Fourier Transform) node for Shake to enable us to very easily erradicate all those kind of repeating patterns, and ease the pain of despotting etc.
On one occasion, a whole bunch of plates we received from the clients looked terrible, scratch marks all over the place - we all thought the footage was irrecoverable.

We put it through the FFT, saw a few bright "pings" in the frequency space image, painted over them to smooth them out, reversed the modifed transform back to image space and the scratches were gone (albeit after a long wait for the processing to finish - the maths involved are not trivial and the process is pretty proc hungry, not something I would imagine Panasonic would add to the GH1 as it would simply kill the recording).

The artefacts I'm seeing on the pics here are very similar to the ones I've seen treated very successfully and very easily in the past. I really don't see any technical reason why there couldn't be a plugin/filter for Nuke/After-Effects/etc that would deal with this. Whether someone will write a plugin or tool for that very purpose is another question.


I'm currently going through a lot of footage I took in Yakushima, deep rich forests, low light, underexposed areas, large patches of solid green moss, Nikon fast primes, and not a bit of noise or streaks in any of the footage (720p only).

Reading through the whole post, after trying to force the camera to get this streaking to happen I can see a very faint hint of it as I underexpose the shot by 3.5-4 stops. I've yet to happen across it on any of the footage I have actually shot though.
My GH1 (Japanese model) is a few months old now and I shoot everything fully manual, iExposure off.

Thanks for bringing up the issue, I now know what to look out for!

NiK
 
Took my GH1 out tonight for the first time and the first thing I shoot with it is some extremely low light stuff at an event in a bar. And I'm impressed. Amazed is more like it.

I shot AVCHD 720/60p, Smooth film mode with contrast at -2 and saturation at -1, ISO1600, 1/60 shutter. The lens was a Zeiss ZF 50 at f/1.4.

I was amazed I could shoot without lights period. There certainly was some noise and streaks as being described here, but nothing I was disappointed about. After shooting with an HVX200 for the last few years I'm used to low light noise and am pleased that the GH1 (with a faster lens than the kit lens) has better low light performance than my HVX200 and a lot less noise. Of course the Zeiss lens has a lot to do with that, but even so, I still could never have shot the same stuff with the HVX200.

I also strolled outside to the street and shot a few minutes of the buildings in the area and cars passing by. I was able to set the ISO to 400 or 800 (I forget which now) and stop up and that eliminated all the noise and streaks I was seeing at ISO 1600 when inside.

In both cases I.Exposure was off, Economy mode was on, white balance was manually set by K degrees, histogram was on.

When shooting I could see the streaks on the LCD when indoors if I looked really hard. I wasn't paying much attention to it though and went into this whole thing expecting to get some kind of noise, streaking, or FPN.

I transcoded everything to ProRes 422 (HQ) and Compressor is currently converting to 24p. Since I shot about 30 minutes of footage this is going to take some time. I'll try to find some time to edit something together and post it.

I'm actually a bit giddy about the overall quality, especially when I walked outside and shot on the street. It's so clean and bright! There was some scenes in a couple previous films I made that we couldn't get the way we wanted because of the size of the camera (getting away with it without permits) and the low-light capability. No one there tonight had a clue I was shooting video, so now that I have a camera that can pull it off we're toying with idea of reshooting those scenes. This thing is a game-changer.
 
Mike@AF said:
That's a completely different issue.
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Hi Mike,

As I'm almost sending my GH1 back to B&H because of the FPN, I would like to know if you still see it with the Zeiss 50 1.4 at night? Because I can't record anything at night without FPN using the stock lens.

Best,

Ricardo
 
I got the same problem. I think it is because the GH1 will set the ISO extremely high in low light condition... may be over ISO 6400 or even ISO12800.. in order to keep the shutter speed at 60 frame per second. So it is just pushing over the limit of the GH1 sensor.
 
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