Pulsating image degradation

Well, see, there they've actually given it enough bandwidth. That's the thing. Instead of trying to use the GoP technology to squeeze the footage down to a ridiculously tiny bandwidth, they kept the bandwidth the same and used the GoP to increase the quality of the footage.

I'm sure, compression-artifact-wise, the NanoFlash is going to be comparable to AVC-Intra. It's still only going to be 8-bit vs. Intra's 10-bit, but in terms of overall compression it should be as clean.
 
I have just seen this on a clip I shot in the woods yesterday with varying light conditions and a very slight breeze. Maybe describing what happened in my case may further help in understanding what's going on and how to avoid it.

Shot 720p 60 at 1/60. Tough light conditions with late afternoon sun filtering thru the trees - lots of stark contrast areas. in Film Mode had everything set at 0 except sharpness at +1. Shot in CMM Standard.

When first looked at footage in Premiere didn't notice any pulsing at all. Footage looked fine other than it needed more color. It was only when I added a quick and dirty saturation boost with the HSL effect that pulsing became apparent. Anywhere where the leaves were turning and reflecting changing light - even very subtly - caused the pulsing in that area. Also true of areas with shadows from those trees on the ground -- where the moiion of the leaves caused varying light. Lowering the saturation level reduced the effect. Turning the HSL effect off eliminated it.

Had planned on using the 3 way color corrector anyway so used that instead and boosted the saturation of the mids and shadows. No pulsing. Even with the level boosted to max at 200. That wasn't quite enough saturation so I added the HSL again, this time at a nominal level and am now a happy camper with no pulsing and a pleasing image.

Am wondering if I would have seen this pulsing right of the bat if I'd had more color in the shot to begin with -- say with saturation set at +1 or +2. Then again, had the pulsing shown up with those settings I'd have no way to correct it. Am really curious whether reducing saturation in those test clips would help reduce the pulsing.

Anyway, seems to me that it's lots of detail (as has been pointed out) and also varying light levels, however subtle, within those detailed areas that are the kiss of death. And it has something to do with saturation.
 
This makes sense because I notice it more when it is static on trees. I too have noticed it is more subtle depending on the color mode in camera.

If only we could get a live HDMI out into one of those flash units. Of course that would mean a big chunk of change for me ATM.

I will probably put it through some more testing in the next couple of days to see if there is anything I can do in camera and in post to tone that down a bit.

I was starting to wonder if it was during the Log and Transfer that it was happening. When I view the .mts files in FCP before Log and Transfer I don't seem to notice it. However the screen is smaller and I haven't found a way to increase the size of the preview pane during log and transfer yet. You guys rock by the way, thanks for the input on it.
 
Try playing back directly from the camera to an HDTV. My bet is that you will notice it there, and that it's not something L&T is adding.
 
so we now have

1) Pulsating image degradation
2) Low light streaking/banding
3) Weak 24p Codec
4) Mud/poor compression
5) Low bit rate

Man this is killing me, I want to get this camera but can seem to pull the trigger
 
"Anyway, seems to me that it's lots of detail (as has been pointed out) and also varying light levels, however subtle, within those detailed areas that are the kiss of death. And it has something to do with saturation."

Try turning sharpness up 1, contrast down 2, and saturation down 1?
 
I have a GH1 and 5D and I can say I have seen this on both cameras so don't feel alone :(

one of the new 7D clips http://www.robgalbraith.com/bins/multi_page.asp?cid=7-10042-10239-10240 has it clearly visible in the Thunder 1080 clip in the rocks below the walkway . As mentioned by Barry, the real only solution is slightly out of focus or slight movement. Wide nature shots of trees, hills and other full focus areas seem always the worse offenders.
 
mtan said:
so we now have

1) Pulsating image degradation
2) Low light streaking/banding
3) Weak 24p Codec
4) Mud/poor compression
5) Low bit rate

Man this is killing me, I want to get this camera but can seem to pull the trigger
Click to expand...
Okay, first of all, items 1/3/4/5 are all the same. And item 2 happens on pretty much all the CMOS camcorders, someone earlier went through and pointed out threads on Nikon forums complaining about banding on theirs, and on Canon forums complaining about banding on theirs.

Here's the bottom line: the GH1 can make exquisitely awesome imagery that people could easily believe could have come from a $40,000 Red One.

Or it can screw up the footage.

Only way you'll know is to play it back and see.

But it costs $1500, including lens, and right now there's nothing on the market that can touch it, anywhere near its price.

The 7D, maybe, but (body to body) it's over twice as expensive.
 
I know it is torture Barry, I want to buy the 7d with a great lens, I can afford it but my wife would decapitate me! The GH1 she already knows the price range, although I first told her 1200 so I will still get it.
 
I think will just repair my hv30 and pass on the gh1, I will wait for something better or for the price to drop on the 7d. I just can't do it, too many problems for so much money.
 
I really want something that will last a while and which I feel solid about, I want to grade my footage with confidence, I want the higest quality possible for such an expensive purchase. Good things come to those who wait. I just don't have enough confidence in this purchase. Maybe the gh2, I will wait.
 
mtan said:
so we now have

1) Pulsating image degradation
2) Low light streaking/banding
3) Weak 24p Codec
4) Mud/poor compression
5) Low bit rate

Man this is killing me, I want to get this camera but can seem to pull the trigger
Click to expand...
Nope. We observe 1, 2 and 4. The cause for these artifacts is likely 3 and 5.
 
1) Not a problem on mine.
2) Don't experience this with properly exposed footage
3) I shoot 720p/60 and convert to 24p in post
4) Not a problem on mine, especially not with 720p
5) So? Symptoms are same as 4. See 4.
 
I want 1080p, not to convert 720 60p to 1080 24p. The gh1 is already outdated in my view. In a year or even 6 months nobody will be even be discussing this camera, while the 5d and especially the 7d will have much more staying power since they can shoot quality 1080p as well as much better photographs on top of that. Gh1 now seems like a gimmick to me. I am so glad there was a delay so that I did not purchase it.

I can get 1080p 24p right now on my $500 HV30. Why pay $1500 for 720p, dof is nice but not that necessary to me.
 
It is possible to shoot a great image with 1080p/24 on the GH1, there is another thread about this, but I simply prefer 720p, I shoot 720p when I shoot on the HVX (usually) as well. I find that it gives me increased flexibility as I can use a 1080p shot to do a composite where I need to downscale, etc, and if I'm going to be editing in 720p I might as well shoot it. Plus with the GH1 (and with the HVX if not shooting 720/24pn) I can get instant slow-mo wherever I want.

There really isn't that substantial a difference between 720p and 1080p, especially once they hit the web, once you consider that most projectors (not like theatre digital projectors which are 2k or higher usually but like normal multimedia projectors, like those in large lecture halls, etc, where it's always good to have screenings) are usually not 1080p, and that broadcast is typically either 720p or 1080i, and that DVD is SD.
 
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