GH2 Banding Issue in my GH2

E

evanrm

Active member
Hi all,

I was hoping to start shooting a short film in a few weeks, but have run into some issues. I applied the No Adverse Effects hack (to hopefully get some better low-light performance), but I noticed a significant band at the lower third of the image. The footage is at 12,800 & 6400 ISO. I then applied the OSG hack pack (which includes a higher bitrate) to see if that helped, but it didn't. So I reverted to the original 1.11 firmware from Panasonic, and the banding is still there, but only in 24/25p. It's not present in 1080i or 720p.

Here's a pic:
Banding.jpg

You can clearly see the line across the middle of the picture. It's really only noticeable against dark backgrounds, but unfortunately my short film was to be done at night! It's about the lower third of the footage. This was done at 12,800 ISO, but it is still present at 6400 and 3200 ISO (3200 ISO with the original firmware reinstalled).

Any ideas? Is my camera/sensor broken? Has anyone else seen this? The band only present in 24p and 25p modes. I've tried the sensor cleaning option but that did nothing to help (if it ever could).

EDIT: I'm using a Lexar Professional 32GB 20MB/sec 133x card. That might make a difference with the hacks, but shouldn't with the original firmware.

Evan
 
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I get it at times to. Although I never go past 3200 iso, and would use lights to get it to a cleaner lower iso. I think it's just a limitation of the cam. Sometimes I tend to forget it's a 700.00 camera, and expect to much out of it.

I get that your doing a low light short at night, but would you really use a 6,400 iso? It would most likely handle the situation much better if you lit it, even being at night. And use a 800 iso. I have found even night exterior scenes need to be lit. I wouldn't advise using available light unless your shooting on something like the fs100.
 
Hi,
Well, yeah, I'm sort of limited in terms of lighting and budget (ie: complete amateur), plus I was hoping to shoot on the street (however, the banding occurs at 3200 ISO as well). I don't mind noisy footage. However, my concern is that I've filmed at the same spot about a week ago, and that band wasn't present. And it's constant, always in the same location in the footage, but only in 24p/25p. It's gone in 1080i and 720/50p.

It seems to my eyes that my hacked footage is extremely noisy, as compared to (admittedly web posted) images from other users in very low-light.
 
I saw the banding for the first time about a month ago, shooting at 3200 ISO into the city sky-glow at night. I am wondering if shooting with a 30 magenta filter, and then correcting in post will help to cure this problem. ( see Project Blue Light thread )
 
Hi,

Maybe, except that this wasn't an issue a week ago, same conditions, same lens same ISO. Something has gone bongo with it. Thanks for all the suggestions. I'll have to return it to the eBay dealer I purchased it from (which hopefully will go smoothly).
 
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That sometimes shows up when I severely underexpose. I don't severely underexpose and it goes away.
 
Did you try different WB's? At extreme ISO's the amplification is done using several different circuits and they are often not matched very well for consumer cameras. This would require hand calibration, so only expensive professional cameras are usually calibrated for this. The first JVC HDV camera was notorious for this, and it could be calibrated requiring plenty of work.
 
There is NO excuse to shoot something without light, The day you DO, you will NEVER shoot without it. Even if it's using simple cheap LED's that cost about $30 each, just a couple of them will truly help you out. Secondly the banding was one of the reasons why I gave up the Gh camera for a Canon which suffers from no banding at high iso's.
 
Returning the camera to the seller for something that is not a true flaw is not going to go well. Shooting a glaring light source at 3200 ISO in otherwise low light is going to do wonky things to the sensor. Shoot at 800 ISO and this will go away. Or shoot at 1600 ISO and don't have a glaring light source flaring the lens and the banding will not happen.

As far as lighting, if you're strapped for cash, halogen work lights (and extension cords) from Home Depot bounced into a white sheet or diffused through a shower curtain or something can work wonders. You probably know somebody who already has this stuff and you can borrow it for free.
 
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