Issues with AVCHD SH Mode!

Coco Bermudez

Coco Bermudez

Well-known member
For tha lest two weeks I have been shooting with the GH-1 for a non profit organization. Let me tell you...the images are completely stunning.

I just noticed an issue though...today we were reviewing most of the stuff shot till now...FHD looks awesome but some of the SH stuff has issues. We shot SH so that we could apply slow motion.

In most of the shots...everynow or then there seems to be a black frame in it....looks as if you were to connect a monitor to a video source and it looses sync for a second.

Has anyone seen this....I can't post any video because of the project itself...but was wondering if anyone has issues. I am not using the stock lens...Nikon primes
 
I actually remember recording and looking at the screen and I saw a one frame black glitch...i did not think anything about it...but then when I checked for it...there it was
 
Very, very short, localised total solar eclipses...

Sorry, I'm no help at all. I'm sure you'll find someone to help you out, though.
 
I suggest you transcode the footage and check if the black frames are still there. If so I think you have to return the camera for replacement. The downside of mass-market consumer electronics, the consumers are the quality controllers.
 
Yeah... I think yours must be defective. I've never seen this.

Is this the first time you've shot a lot of 720p stuff on your cam? I'd be concerned if you've done a good amount of 720p stuff and now it's just starting to error. That'd suck.
 
Hmm. Have to say I haven't experienced anything like this in SH mode. Maybe try a different brand of SDHC card? Other than that, it sounds like maybe a defective camera.
 
I would test a different brand of card with the same settings and see if you can recreate the problem. I haven't seen this black screen at all, but I have seen a couple of freezes/dropped frames which I'm fairly confident is due to the sdhc card not keeping up. There was a thread about this issue a while back and the consensus was that it was a defective camera, but I'm not so sure. I guess it's worth a try before sending in your camera.
 
I use kingston 8 GB class 6 cards (holding 1 hour of video) and have shot 12 hours so far, only in SH mode. Mostly everything has been fine, but on the last card I noticed exactly the same thing as you describe. I usually watch the material on a TV played out from the camera first, because I can't play avchd files on my computer, and didn't really notice any glitch. But when I made a standard definition proxy file to work in my NLE I saw a single black frame. But you say the frequency is "most shots" whereas I had about three instances of a single black frame on a whole card (maybe 150 to 200 separate clips, with only say three spoilt by a black frame).

I did not notice it on previous footage, but then I wasn't looking for it (just a single black frame). I don't know if this is a card performance issue (rather than a camera issue), and I'll be looking to see if my problem gets worse. If it is a card issue, would it help to format a card before re-use instead of just deleting the files (to "refresh it"), or would it make no difference? Does frequent formatting age a card more quickly?
 
TrueIndigo said:
I use kingston 8 GB class 6 cards (holding 1 hour of video) and have shot 12 hours so far, only in SH mode. Mostly everything has been fine, but on the last card I noticed exactly the same thing as you describe. I usually watch the material on a TV played out from the camera first, because I can't play avchd files on my computer, and didn't really notice any glitch. But when I made a standard definition proxy file to work in my NLE I saw a single black frame. But you say the frequency is "most shots" whereas I had about three instances of a single black frame on a whole card (maybe 150 to 200 separate clips, with only say three spoilt by a black frame).

I did not notice it on previous footage, but then I wasn't looking for it (just a single black frame). I don't know if this is a card performance issue (rather than a camera issue), and I'll be looking to see if my problem gets worse. If it is a card issue, would it help to format a card before re-use instead of just deleting the files (to "refresh it"), or would it make no difference? Does frequent formatting age a card more quickly?
Click to expand...

Wow...at least I know I am not going crazy. We have been analyzing the footage today and yes the issues are there...BUT not only that...there seems to be some luma shifting...it looks as if we were playing with the iris ring. It is slight...but noticeable. We shoot manual with AE Lock and all the other good stuff. From day one we have turned off almost everything in the camera's menu so that the camera only operates with the basics without using power or resources unnecessarily.

We formatted the card twice before each shoot....One for formatting and immediately for good measure. If the shots are quick and dirty...maybe tops 10 seconds..everything is fine. For longer shots, the problem occurs. We have lots of shots that were 1 to 2 minutes...that is where it occurs mainly.

I believe this is a camera issue and would guarantee that every single GH-1 has the same issue...it is the fact that probably not a lot of us use the mode for long periods of time.
 
With my PAL model and Panavision SDHC Class 4 16 GB card I've shoot upwards of 20 minutes non-stop just for the kick of it and don't have a single black frame anywhere with one exception: when I intentionally kept on recording despite the camera warning that battery was running out of power, then in the last minute before it gave up and auto-shut down there are a couple of black frames and luma shifts.
 
I turned everything off too (i.exposure, OIS) and tend to use manual lenses because I don't get on with the kit lens. My camera is PAL. I will be looking at my material to see if this is more frequent for me than I first thought.
 
Or your unit have a power issue. There are enough NTSC GH1s out there that if this was a widespread thing it would have been reported previously.
 
I've shot many hours of footage in AVCHD/SH mode and under a variety of conditions from full auto to full manual. I've never seen a blank frame. What I do see is luma shifting while zooming using the 14-140 lens. While zooming in/out you can see little flickers of light like someone is flicking the aperture. Is that what you are seeing? If so, all GH1's do that. I'm hoping a firmware fix will solve that.

Mike
 
mikeydvx said:
I've shot many hours of footage in AVCHD/SH mode and under a variety of conditions from full auto to full manual. I've never seen a blank frame. What I do see is luma shifting while zooming using the 14-140 lens. While zooming in/out you can see little flickers of light like someone is flicking the aperture. Is that what you are seeing? If so, all GH1's do that. I'm hoping a firmware fix will solve that.

Mike
Click to expand...

Isn't this just because the aperture is changing? The farther you zoom the less wide-open the lens allows. Of course this doesn't apply if you were shooting above ~f6.
 
mikeydvx said:
I've shot many hours of footage in AVCHD/SH mode and under a variety of conditions from full auto to full manual. I've never seen a blank frame. What I do see is luma shifting while zooming using the 14-140 lens. While zooming in/out you can see little flickers of light like someone is flicking the aperture. Is that what you are seeing? If so, all GH1's do that. I'm hoping a firmware fix will solve that.

Mike
Click to expand...

I have noticed the luma shifting...and I only use manual Nikon primes. I set the aperture and never touch it until the camera stops recording. Again, all this only happens in the SH Mode
 
You must log in or register to reply here.
Back
Top