GH2: Blue horizontal banding?

HVXguy said:
Well that would be rather short sighted wouldn't you say?
Blu-Ray is hardly used except for entertainment titles.
I pushed clients hard to adopt DVD and then Blu-Ray.
No one wants to distribute anything on Blu-Ray.
Hollywood uses it and I have several Blu-Ray players......
But the future of delivery is on-line. I can encode & play MP4 files
on a PS3 or WD TV and have several clients using this method
to play HD video at Trade SHows & Conferences.
I dare say that I have not burned a Blu-Ray disc - and don't plan to.

Now don't ask me about 3D - that is a whole new ballgame.
Click to expand...

ok but still, if it's online then once again you don't have to have 25p
 
HVXguy said:
Take a look at these clips and tell me why Panasonic won't sell millions of GH2's?????

http://vimeo.com/17245744

http://vimeo.com/17062701

http://vimeo.com/17294099

http://vimeo.com/17378684

http://vimeo.com/17402970

http://vimeo.com/17414803

http://vimeo.com/17436419

http://vimeo.com/17464042
Click to expand...




on the clips of PB we're also fell for the GH1 and 7D.
Only the Hack of Tester13 me again warms the GH1
I think nothing more Pb - I will not buy a GH2
sry for translator
 
kainekainekaine said:
Scrub that last post, its there in 1080i and 720p too and mjpeg albeit the bands seem in different places. Its also in the tele 1:1 mode but goes away upto 1/50th, appears at 1/100th. As it appears at 1/50th without the tele, I think the tele crops the part of the sensor just above where this band occurs without thats why its not showing in 1:1 mode at 1/50th. The higher the shutter the higher the band occurs until evetually it hits the part of the sensor the 1:1 is cropping out.
Click to expand...

So I tested crop mode on 24p as well, got the band to appear, but only once I was at 1/80th or above. 1/60 or below and there was no visible band. I believe you are right in that once it crops in, since the band seem to jump up the sensor, it must have to be a certain shutter speed for the band to show up in the area of the sensor that being magnified.

Guess thats good news at least, that if we want to shoot in 1:1 we can shoot at a normal shutter of 1/50th, and just resort to 1/30th when not in 1:1.
 
I could be just hallucinating but with the first batches, could there be a possibility that either the black or the grey ones were made better?
 
mojo43 said:
I don't like either equally... :(
Click to expand...

I'm really struggling to see the GH2 band (not banding) in any reasonable footage. If your published video is going to highlight the band, you've got bigger problems than this forced artifact.

GH1 was a different beast entirely. Easily identifiable vertical bands everywhere, and whispy horizontal banding, at ISO 1600, and underexposed ISO 800.

Massive, massive difference. This is a mountain out of a mole hill.
 
Right, as I'm nice, I've done a whopping big test of the band in the GH2. I've never denied it's not there, I just wanted to see under what conditions it shows, how severe it is, and understand more if it could become a problem in real shooting. As I've said above, and now after this testing, I still stand by my suspicions, it's all going to OK {{{hug}}}.

Seriously, is it it a flaw? I'd say yes. Is it a characteristic? Yes. Is it a show stopper? No. In fact it's an extremely minor inconvenience. How do I get around it? Shoot ISO 800 in low key scenes where you have significant areas of vastly underexposed (3ev+) midtones. If that's all I need to remember, well, I'm a happy bunny.

So to the testing I did. Courtesy of my helpful assistants, the four nameless fish, and their humble abode, the tank. I wanted to shoot under three different lighting conditions, the tank light, the room light and a torch. This would simulate a couple of different looks, and different distributions of light, much like you'd do in different shooting scenarios.

I shot with the GH2, 1/50 with Canon FD 1.4 varying from f1.4 to f22.

I'm in the process of uploading the joined MTS files (using the excellent tsMuxer - no re-encode) to my Vimeo Plus account. It's 1.5GB, and I have 5Mb upload, so it'll take a bit (currently showing 40 minutes). For now, here are my own subjective test results. I will post a link/embed the video once the upload is completed. The video is in the order of the testing as listed below. There's no overlay text as I didn't want to re-encode. It's obvious when the scene changes though, just remember the order.

Test results:

Tank Light - Fluorescent (AC)
- ISO 800
○ No visible band through f2-f22
- ISO 1600
○ Faint band by about f5.6 (area about -3ev)
○ More visible by f8 (area > -3ev)
○ Disappears in complete darkness (about f14-16)
- ISO 3200
○ Faint band by about f7.1 (about -3ev)
○ More visible by f9 (> -3ev)
○ Disappears in complete darkness (about f20)

Room Light - Energy Saving Bulb (AC)
- ISO 800
○ No visible band f1.4-f22
- ISO 1600
○ No visible band f1.4-f22 (maybe slightest of faintest , but could be illusion due to looking TOO hard)
- ISO 3200
○ Very faint band at about f6.3 (-3ev)
○ Visible band at about f8 (> -3ev)
○ Darkness from f11 and no band

Torch Light - DC
- ISO 800
○ No visible band f1.4-f22
- ISO 1600
○ No visible band f1.4-f22 (maybe slightest of faintest , but could be illusion due to looking TOO hard)
- ISO3200
○ Faint, almost imaginary (is it actually there or not) band in the underexposed edges by about f8, have to move my head around up and down the LCD monitor. Thought it was imaginary at first, but I think there's something there.

Viewed on plasma, actually even harder to discern the band, but still present. Visible becomes faint, faint becomes that imaginary feeling.

Video is converted and ready to download.

............Now can we get on with shooting the flaming thing and enjoying it please :D
 
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Hmm... I'm really anxious to play with that footage when it's uploaded. I might try my hand in Apple Color at hiding the band with a secondary color correction mask. If I can succeed, I'm gettin' this puppy for sure.
 
Internet connection died while uploading for 10 minutes. Fortunately Vimeo uploader does it at the bit level, so it's continued where it left off...which is nice. Showing about 25 minutes. I don't know if the mts will be available to download straight away, as I'm certain the player version won't.

By the way, it's my usual crude testing, out of focus crap. I just wanted to get something rough captured and shared.
 
Video is done, and ready to download....all 1.5GB of it :)

Dropped off the page, so added it again so folk don't need to backtrack:
 
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Is it a good idea now to buy the gh2. If the camera I purchase has the blue banding could I just send it in for a fix or wait for the firmware update?
 
Just got mine today. Experiencing banding... in this clip it is more like discolored flickering...


It's not really evident in the web compressed video. Here is the ProRes that was brought into FCP: http://bit.ly/fhGEz8
 
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Point your GH2 at a TV or monitor and crank up the ISO to 3200.

Oh and face detection even works if you are shooting a TV with people on the screen. :)
 
itimjim said:
Courtesy of my helpful assistants, the four nameless fish, and their humble abode, the tank. I wanted to shoot under three different lighting conditions, the tank light, the room light and a torch. This would simulate a couple of different looks, and different distributions of light, much like you'd do in different shooting scenarios.
Click to expand...

Thanks for the test and taking the time.

How old are your two orandas?
 
farfromsubtle said:
Just got mine today. Experiencing banding... in this clip it is more like discolored flickering...

It's not really evident in the web compressed video. Here is the ProRes that was brought into FCP: http://bit.ly/fhGEz8
Click to expand...

Thanks for doing these daylight tests. I haven't received my GH2 yet.

Does the very subtle flickering in the shadow area (I see it in the brown fuzzy cloth to the left of the cat's face) occur if I-Exposure is turned OFF? (or is it called I-Dynamic on the GH2?)

And: Is it affected by the Noise Reduction setting? As a separate test, try setting NR to -2 and also try +2. Does that make a difference? Thanks again.
 
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itimjim said:
Video is done, and ready to download....all 1.5GB of it :)

Dropped off the page, so added it again so folk don't need to backtrack:
Click to expand...

Hmm... I'm on a Mac. So far nothing I have (Compressor, MPEGStreamclip) lets me open the .m2t file to transcode it (or for that matter, view it).

EDIT: Nevermind. VLC plays it (of course).

Hmm. I am having a really hard time seeing this issue on my 27" iMac. The high ISO noise might be distracting me from it... Which to me is an encouragement that if you're shooting high enough to get this band, other noise is going to contend for its attention...
 
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