PDA

View Full Version : GH2 "And the greatest of these is...."



Framerate
12-15-2011, 09:51 AM
(sighhhhh)

Just as 'Charity' is deemed to be the greatest of the three virtues - surpassing it's siblings, 'Faith' and 'Hope' - so, of the three great laws that govern our lives, 'Godwin's', 'Murphy's' and 'S*d's', it is the latter one which is usually pre-eminent.

As in the case of my replacement GH2.

I waited almost a year before buying a GH2, hoping that the banding issue would be silently fixed by Panasonic.

When my new camera arrived from Amazon it turned out to be a September 2011 model - which was enough to inspire hope that the banding would have been long gone, and the problem would have been solved.

Alas, not so. Underexposure at even moderate iso's revealed the banding problem I'd read so much about. Present at 50th shutter, gone at 25th shutter, and moving merrily up and down the screen at other randomly selected shutter speeds.

The hack made no difference, the new firmware made no difference - it was there, clearly to be seen in the VF, and even more clearly to be seen when replayed on a screen.

So, it was back to Amazon with it - who, being Amazon, made a mess of the return and delayed the arrival of the replacement camera.

While waiting I drooled over the test reports of the Nex-7 (actually, more like 'lusted'....) and I made up my mind that if there was any banding, whatsoever, on the new GH2 I'd send it back by return, sell my Panasonic lenses & accessories, and settle down to wait for the Sony.

Actually, I was almost certain that *was* what would happen.

Enter the replacement GH2, an October 2011 model, and some wearily familiar tests - which is when the Law of S*d kicked in.

Not a hint of banding, even when lowering the EV off the scale. I tried (almost desperately) to provoke that familiar black line across the image - but the GH2 just wouldn't play ball.

Yes, there was noise - but absolutely nothing that could even remotely be construed as a band.

So there we have it - I can state conclusively that, like the GH1 before it, the GH2 differs in quality between batches.

Why? - who knows?

My own pet theory is that the thing is (obviously) the sum of its parts, each one of which is made to a certain tolerance. If all or most of the components happen to be near the optimum design criteria, then the camera, itself, will be 'as designed'.

If, however, those components are a little bit below par, then each one will contribute to poor performance - and that banding.

That's just my own theory, of course, but I can't really think of any explanation for such remarkably varying image quality.

It goes without saying that this shouldn't be the case! - we're not buying wine, here :cheesy: There should be no 'good years' and 'bad years' (or, more accurately, good months and bad months) We shouldn't have to dip into the bingo bag and hope we get a lucky number!

Anyway, there it is - but I'm pretty sure that if I'd been anxiously waiting for a 'good' GH2, it would have arrived with more noise and bands than a combined armed services parade.... That's exactly how S*d's Law operates :cheesy:

roei z
12-15-2011, 10:33 AM
so you DON'T have banding? lucky bustard.

Framerate
12-15-2011, 11:30 AM
so you DON'T have banding? lucky bustard.



No, no banding - and I've tried really hard to provoke it ;)

Another 'bad' GH2 would have meant I could have gone for the Sony with a clear concience (my owner sometimes starts to get restive about the amount spent on photo stuff)

As it is, I can't justify spending 110% more on the Nex...

I came across this with the GH1 - I remember posting some Vimeo 'no banding' tests when I got my December 09 model - yet someone on DPR bought a January 2010 GH1 and it was riddled with FPN.

There seems no logic to it - you might think that early samples would be bad and that later cameras would have the problems sorted, but it just doesn't seem to work out like that - it really *is* a lottery, genuinely.

The GH2 I returned was serail 01J (whch, as Pansonic omit the 'i' in the date sequence) made it a September 2011 camera. This one is 'K', or October 2011, yet it's night & day different for banding.

It's ridiculous - how is anyone supposed to buy a GH2 when they have to take pot luck on wheter it works properly or not?

The main lesson, though, is to only buy from someone like Amazon who, although their middle name is 'inneficiency', are scrupulously fair about returns and refunds. Buy one, if it's no good, change it - and change *that* one as well, if you have to.

Some small stores would get very sniffy about it, unlike Amazon.

mcbob
12-15-2011, 01:23 PM
I've never had banding, either. No idea which batch.

Ed Kishel
12-15-2011, 01:27 PM
I just got a GH2 (mainly for stills)- but have not tested it for this issue in the video mode. What is the best way to provoke it?

Zxander34
12-15-2011, 01:42 PM
I just got a GH2 (mainly for stills)- but have not tested it for this issue in the video mode. What is the best way to provoke it?

+1

I would also like like to do this since my GH2 just arrived.

stoneinapond
12-15-2011, 02:21 PM
What is the best way to provoke it?

Call it a point and shoot....

Framerate
12-15-2011, 02:30 PM
+1

I would also like like to do this since my GH2 just arrived.

Ed & Zx,

The banding is most noticeable in Progressive mode (24p, and now 25p for Europe)

It *is* there in 50i (at least, it was in my previous camera) but is very faint, and unlikely to be noticed unless you really look for it.

It manifests itself in underexposed/higher iso situations. I know that we *shouldn't* underexpose - but life's not like that, and there are often situations when it's impossible to avoid part of the image falling into underexposure.

Best way to see it is against a plain mid-tone surface (a wooden bookcase, for example) In progressive mode, use a relatively slow lens, like the kit lens, and dial up the iso to 3200. The EV meter should be well into the minus segment (depending on the lighting) and the shutter speed set to 50/1000.

If it's there, you will see the band about a third of the way down the VF/LCD - you're looking for a dark, fairly thin, distinct horizontal line right across the image. (if you activate the grid pattern it will fall just below the thitd grid line)

Change the shutter to 40/1000 and the band will move down to just above the bottom grid line. Change again to 25/1000 and it will vanish off the screen.

Conversely, changing to faster shutter speeds will shift the band upward.

If it's there you will know it - it's not 'noise', it's a very distinct line that looks almost like the sort of line that you get when playing back old damaged video tapes.

Ed Kishel
12-15-2011, 02:41 PM
Like this?


http://vimeo.com/17281822

JMZ
12-15-2011, 02:52 PM
Ed,

Thanks for posting this. It was extremely helpful.

Framerate
12-15-2011, 03:03 PM
Like this?


http://vimeo.com/17281822



Thar she blows!! :cheesy: - it can be much darker than that (depending on the lighting/background, I suppose)

Ed Kishel
12-15-2011, 07:36 PM
Well if I go to iso 3200 and stop down to f11 in a dim room then yes I think my gh2 does this. It's so faint though, I stress "I think" it does. On my cam I really have to go for an ugly picture to make it happen. Perhaps this issue has different levels of intensity- if so I would rate mine as minimal at best. It's definitely nowhere near some of the other videos I've seen showing this issue.

Returning it and hoping for a different one is such a crapshoot- you might change it out 3 or 4 times before you get one that's perfect. Framerate was lucky to get one on the 2nd try. With mine it's so minimal I don't want to even try. My main video camera is my AF100 anyway, so I can live with it (as long as it stays in iso 3200 at f/11). This along with the fact the cam does so many other things so well- I'm still happy with it.

Framerate
12-16-2011, 03:39 AM
Well if I go to iso 3200 and stop down to f11 in a dim room then yes I think my gh2 does this. It's so faint though, I stress "I think" it does. On my cam I really have to go for an ugly picture to make it happen. Perhaps this issue has different levels of intensity- if so I would rate mine as minimal at best. It's definitely nowhere near some of the other videos I've seen showing this issue.

Returning it and hoping for a different one is such a crapshoot- you might change it out 3 or 4 times before you get one that's perfect. Framerate was lucky to get one on the 2nd try. With mine it's so minimal I don't want to even try. My main video camera is my AF100 anyway, so I can live with it (as long as it stays in iso 3200 at f/11). This along with the fact the cam does so many other things so well- I'm still happy with it.


I think that the problem does vary in intensity, from nothing, through minimal, to severe.

In your shoes I don't think I'd return it either - you could easily get one that was worse.

Ed Kishel
12-16-2011, 07:39 AM
besides, at the settings where this happens (on my camera anyway) I'm more bothered by the noise than any band I might see.

j1clark@ucsd.edu
12-16-2011, 10:10 AM
besides, at the settings where this happens (on my camera anyway) I'm more bothered by the noise than any band I might see.

Initially I thought this thread was about 'quantization' banding where one has a gradient, such as blue sky on a clear day, and the 'banding' that can be seen because of
the bit depth that the image is digitized to...

But the video shows a completely different artifact... and fortunately, I have 1) a GH1... perhaps it shows this at 1600 ISO which leads to 2) I never shoot anything
that I actually want to see again at anything higher than 400 ISO... typically 200 ISO... I have done some 800 ISO for 'happy shots', and have not noticed this artifact
in the GH-1.

But philosophically, I tend to shoot with higher light levels, then 'adjust' down in post processing. If I wanted 'surveillance' camera look... I'd probably use a cheap webcam these days,
or the Sony Handy cam that I have that dos 1080 60i HD... then mangle it into 24p... it even has a pseudo low light option... gives that nice 'green' look...

Ed Kishel
12-16-2011, 10:34 AM
My workaround would be- if I HAVE to shoot at iso 3200 in dim light, I will move to 1/30 on the shutter. But although this doesn't bother me so much...don't get me wrong- Panasonic should still have fixed this by now. One would expect a noisy image at these settings, but not a dark line through the picture.