'Good' and 'bad' ISO settings on GH2
 

Interesting info on 'good' versus 'bad' ISO settings on the GH2

Good ISO: 160, 320, 640, 1250
Bad ISO: 250, 500, 1000 and 2000

Re: 'Good' and 'bad' ISO settings on GH2
 

Jim,
Generally those setting have been disavowed. Most of the DP's are using 200, 400, 800, 1600. The 160 multiples settings produce issues with midtones and shadow detail. For 1600 you should use +1 or 2 in NR setting. For lower ISO use NR -2.

Re: 'Good' and 'bad' ISO settings on GH2
 

This is a bit confusing. Will the real expert(s) please raise their hands? Is this guy faking his screen shots? Who is "generally disavowed"?

Re: 'Good' and 'bad' ISO settings on GH2
 

I fully agree, very confusing, and I am NOT raising my hand, but I have looked into this subject, and while the cap on tests do argue for the 160x ISO setttings, the more I dug into the matter, the more I was convinced that the conventional wisdom is 200x settings. In fact, the guy who made the video you posted, Todd Norris, says this: "Also, someone else did a test that shows ISO 320 and ISO 640 contain lots of chroma noise in the low midtones and shadows. I think the best ISOs for GH2 are 200, 400, 800 and 1600 (1600 needs NR turned up to +1 or +2)."

Re: 'Good' and 'bad' ISO settings on GH2
 

Footage shot at different ISOs with the lens cap on is just plain useless for evaluating real life performance.

Re: 'Good' and 'bad' ISO settings on GH2
 

I agree and a lot of people did that test and thought they'd figured out ideal ISO setting. I think Todd Norris though may have proffered up the definitive answer. the 160x indeed seem to have chroma noise in the shadows which is more yucky than vanilla luma noise.

Re: 'Good' and 'bad' ISO settings on GH2
 

OK, now that we have established how we can't do it, how can we evaluate noise at different ISO levels?

Re: 'Good' and 'bad' ISO settings on GH2
 

Just shoot the same scene using different ISO settings & adjusting the aperture so that exposure is identical. I haven't formally done this but I see no discernable differences in noise between the different ISOs that 160/320 etc are better/worse then 200/400 etc

Re: 'Good' and 'bad' ISO settings on GH2
 

Hello Everyone!

Well here I am in 2012 revisiting this issue :-)

I actually just got my GH2 a couple of months ago, so this is all new to me.

I recently ran some extensive tests, and have some conclusions, and even more questions.

I hope someone actually reads this post and we can delve into the noise problem even further.

First of all I ran some of my tests using a target that contains many squares of different color and value. I underexposed it to get the most grain/noise possible.

Other tests were of constructed scenes in my studio.

* I found no consistent evidence that choosing 320 ISO from a higher ISO vs a lower ISO made any significant difference in my footage.

* I shot scenes at different ISOs and different NR settings and found that the NR settings are useless on my test footage, and that the 160/320 vs 200/400 argument is not valid according to my tests. The noise graduated consistently as I went up in ISO. I always started at 3200 ISO and then went down to the test ISO just to avoid the dreaded ISO bug, if it were actually present.

The most troubling aspect of my tests is that I get noise at low exposures even at ISO 160, the lowest setting we have.

Even my SD Canon XL-2 did way better than this!

Worst of all is that the noise ends up looking like blotches rather than a fine film like grain, so the NR software has a really hard time eliminating it (at higher ISOs the noise looks better because it a) looks more like film grain. b) can be removed more easily by NR software.


My Question to all of you is: How to get rid of the noise (i am running firmware ver 1.1)?

I know, that's the holy grail, but do you think that some of the hacks may actually help reduce noise at 160 ISO and above?

Any light on the subject is deeply appreciated!

AM

Re: 'Good' and 'bad' ISO settings on GH2
 

I am NOT an expert.
I've read everything I can find on it, especially on Personal View and tested it the best way I know how, shooting things that I know will cause noise, then seeing how much.

First, in my opinion and tests and most of the high dollar color graders agree, in camera NR is detrimental to the IQ.. It gets -2 on everything.

Second, the hacks make more difference with grain than anything else. Sedna and CM Night being the finest grain noise.

I shot candles a night. That's a guaranteed noise machine.
I found I had less noise shooting 200______ in other words, line 2 and that Neat Video cleaned it better than other settings.

Now that's what I found using very unscientific methods and is far from the scripture.