Low Light Streaks - Is my camera faulty?

The notable difference from the LCD preview and actual recording had been mentioned previously (I believe Kholi did in his first tests)
 
PhilD said:
... What you see in the LCD/ VF is very different between your previewing and the moment you start shooting. Try it.
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Wait a minute - maybe i missed something. So you can´t evaluate the picture + right exposure before shooting? How do you know what it looks like?
 
I'd be interested to see ISO 1600 movie frames from people's new GH1s...

I get a 2nd GH1 tomorrow here in Taiwan, so may do a test concerning the newborn GH1 banding issue once I get back to England the following day.

Also worth mentioning, although obvious, that the noise reduction doesn't kick in until you hit record. So although you get a decent preview on the screen in creative movie mode, at the proper frame rate, it will look a lot noisier than the final recording.

In stills mode, I have noticed the sensor is very noisy at ISO 100 - yes, 100, with long exposures. With noise reduction turned off in fact the resulting image is unusable. I am alone in finding that unusual? I guess there is indeed some kind of external interference, maybe from the AF motors, LCD or OIS that causes this... because even on a long exposure, ISO 100 should not be noisy. Maybe I'm wrong.
 
commanderspike said:
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I get a 2nd GH1 tomorrow here in Taiwan, so may do a test concerning the newborn GH1 banding issue once I get back to England the following day.
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Good idea. I´m particularly interested in whether the streaks occur mainly in higher iso values or already in lower ones like 100, 200, 400? Is there a way to avoid it?
 
The Banding I just saw in another clip reminds me of radio frequency interference. Panasonic should address this if it's a RFI issue...

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PhilD said:
False. At night or say in a low light area it doesn't show you what you will shoot (in fact it never does unless there's some way to alter display settings).
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That is not how my GH1 seems to be working when the dial is switched to Creative Motion Picture Mode (the icon that has the movie camera followed by the letter M). In that mode, both the LCD and LVF give me the same image during preview as when I hit record. On other modes (Still Pictures), the image seems "pumped up" to a higher ISO before hitting the button.

I discovered the Preview Button which is the button on the bottom to the right of the LCD. It has a trashcan icon on it. It shows you a preview of your aperture and shutter speed settings (thereby bypassing the "pumped up" look). You first have to go into the menu and select Preview Hold to "ON". Then hit the preview button, followed by the Display Button. The Display button then toggles On and Off the preview. This is a bit of a pain, but it replicates the Depth-of-Field Preview buttons on 35mm film SLR's.
 
After spending more than a month working with the GH1 on a project. I can safely say that if you set the ISO at 400, your effective ISO is much, much higher.

If you have access to a light meter, set it at ISO 2500 and then your camera at 400 and take a look at the results, it's pretty stunning.

There's some T1.4, 400 ISO, 5:AM footage lit only by headlights and streetlights that is drop dead gorgeous.

Keep your GH1 at ISO 500 and below to avoid streaking, 400 ISO if you're going up to a big, big screen. As I mentioned 400 ISO is effectively 2500 ISO.
 
Illya Friedman said:
After spending more than a month working with the GH1 on a project. I can safely say that if you set the ISO at 400, your effective ISO is much, much higher.

If you have access to a light meter, set it at ISO 2500 and then your camera at 400 and take a look at the results, it's pretty stunning.

There's some T1.4, 400 ISO, 5:AM footage lit only by headlights and streetlights that is drop dead gorgeous.

Keep your GH1 at ISO 500 and below to avoid streaking, 400 ISO if you're going up to a big, big screen. As I mentioned 400 ISO is effectively 2500 ISO.
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I've seen footage filmed high ISO, and no banding, and then others who get it...
Panasonic has been told about this issue since the G1 came out last year. What's causing it is
not officially known. However to it looks like RFI issues to me. On photography forums they have theories
that it something to due with RFI or another unknown electrical interference...


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Wasn't there a topic on using also true ISO settings like 160-320-640-1280 etc on the GH1. On the 5DMII there are comparisons showing that certain iso's are noisier..??

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Um...according to my light meter, 400 ISO equals about 400 ISO on the GH1. And the very same settings on my Olympus E-500 (f5.6, 400 ISO, same shutter speed as GH1) produce the same reading and the same exposure. Setting my light meter to 2500 and basing my cameras exposure to that produces an image that is very dark. I think your meter is not correct.
 
Have new information about the banding issue.

On my two Japanese cameras, one on factory settings, one I'd used on a shoot, they had radically different noise issues. I tested this by leaving ISO on Auto and putting the shutter speed ridiculously high in a day light lit room.

In shadow areas of the room, the GH1 I'd had with me since May had awful red banding and streaks of noise.

The factory settings GH1 was much better, displaying very little visible noise and the noise wasn't bright red.

At first I thought maybe the sensors were different, one being better than the other.

But after comparing the camera settings I found iContrast was enabled 'full' on one, whilst it was off on the other.

Enabling iContrast resulted in the same noisy streaking on the other camera.

It seems to boost the sensor ISO output in dark areas of the image in an attempt to bring out more dynamic range and detail in the shadows, but of course this also results in the noise and banding issues we have seen here.

So... if you are still concerned about banding, turn off Intelligent Contrast, at least in movie mode when shooting at high ISOs.
 
I had this issue too. but only on the first day. second day it vanished and iso 1600 was better than iso 400 the day before. strange.
 
sirk said:
I had this issue too. but only on the first day. second day it vanished and iso 1600 was better than iso 400 the day before. strange.
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You probably turned off Intelligent Contrast by the 2nd day :) Try it now... does 'on' return the banding issue in certain conditions, i.e. fast shutter, high ISO, or dark scenes?
 
commanderspike said:
You probably turned off Intelligent Contrast by the 2nd day :) Try it now... does 'on' return the banding issue in certain conditions, i.e. fast shutter, high ISO, or dark scenes?
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Well that's interesting. Does that feature come normally enabled in the factory settings? Not so ""intelligent"" after all...Possibly!
 
dvbrother said:
Um...according to my light meter, 400 ISO equals about 400 ISO on the GH1. And the very same settings on my Olympus E-500 (f5.6, 400 ISO, same shutter speed as GH1) produce the same reading and the same exposure. Setting my light meter to 2500 and basing my cameras exposure to that produces an image that is very dark. I think your meter is not correct.
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The scene is darker yes, but not incorrect. The response on the GH1 is far from linear. You see way more in the low IRE, and the knee is aggressive.

A simple test proves all. Get a small light source in a dark room, put something "on exposure", something 2-under, something way under "black", something 3-over, and something way over "white". Rate camera at 400 ISO. Shoot the 400 ISO on exposure, now re-meter at at 2500, and shoot your "on exposure" at that new stop. Watch both clips back to back on a calibrated monitor.

Which actually looks more correct? You're not looking for which looks brighter, or which allows you to see "more" in black. Which looks correct? Maybe a better way to phrase that is which looked more like your eye actually sees it. The toe of the GH1 is way more sensitive than the ISO rating.

I did this metering test with the DP and 2x other meters, and 2-different monitors. All read the same.
 
commanderspike said:
Have new information about the banding issue.
.........
The factory settings GH1 was much better, displaying very little visible noise and the noise wasn't bright red.
.....
Enabling iContrast resulted in the same noisy streaking on the other camera.
.....
So... if you are still concerned about banding, turn off Intelligent Contrast, at least in movie mode when shooting at high ISOs.
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Good discovery. So is this now the ultimate solution for the streaks and lowlight banding? If you turn off "iContrast" streaks will never occur in lowlight? Can other owners confirm this?
 
Likewise! Can't seem to find iContrast, only iExposure, even did the RTFM thing and couldn't find iContrast in there either.

Might it have been possible that it was iExposure "off" and not iContrast that rectifies the banding situation?
 
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