Compression artifact or does my camera have a problem?

I've never ever been bothered about crap along the edges of any camera I've used. It's always going to be odd things going on there. On film cameras both gunk can build up against the gate edge over a shooting day and also the inside edge of the gate could actually reflect light onto the negative. On analogue video cameras both top and bottom lines had all kinds of distortions and artefacts going on from the tape recording and on digital ones the sensor does some art additions of it's own. That's why cinemas have a black matte around the screen and television sets project the image bit larger than the phosphor screen and flat screens crop off a few lines around the image - to cut the crap out. Nothing to new in other words and I dare say nothing to worry about. Nothing at all.

Cranky said:
The last image has trees with horrible teal trunks, unless they were painted like this in reality.
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That's a fence with teal painted poles ferchrissakes. Doh.
 
Martti Ekstrand said:
I've never ever been bothered about crap along the edges of any camera I've used. It's always going to be odd things going on there. On film cameras both gunk can build up against the gate edge over a shooting day and also the inside edge of the gate could actually reflect light onto the negative. On analogue video cameras both top and bottom lines had all kinds of distortions and artefacts going on from the tape recording and on digital ones the sensor does some art additions of it's own. That's why cinemas have a black matte around the screen and television sets project the image bit larger than the phosphor screen and flat screens crop off a few lines around the image - to cut the crap out. Nothing to new in other words and I dare say nothing to worry about. Nothing at all.


That's a fence with teal painted poles ferchrissakes. Doh.
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Thanks much for the post - I'm not too bothered by it - it's not make or break and I just needed to make sure that it wasn't something "wrong" , I'm a still photography guy by trade an I'm going to be cropping anyways so it's not a real problem - just curious mostly.
 
Car3o said:
that image is old news. or video. it's messed up from top to bottom. that's been a problem with these detailed scenes and fast pans. i use 720p for that. but to me this 8pixel line is like finding a needle in a hay stack.
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I guess the point is that this issue pops up in all of my 1080/24 footage (I don't see it in my 720/60 stuff), and not just in detailed scenes, and it's not a needle in a haystack, honestly, if you've actually watched clips with the worst examples of it (and these aren't caused by improper use/exposure, all you need it to shoot an area that has deep blacks on the bottom of the frame) and it sticks out in a big way - it's not a constant sort of pattern either, it displays as if it were noise and in bright colors, it moves back and forth like a wave - and so in dark scenes it can be very visible.

I'm not saying this is make or break, nor am I saying that a camera of this price has to be "perfect," but it is worth discussion.
 
Car3o said:
this isn't a shameless plug...but can you point it out on these? not looking for 2x zoom either, just looking at a red line pointing to where it's messed up. i'm still having trouble finding it on your grabs.

http://picasaweb.google.com/RichB.Hibner/ThursdayGrabs#
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I don't see it any of those grabs. However, I also don't know what mode you were shooting and the grabs you posted are not full resolution.

I do not have this problem with 720/60 footage (have not tried 720/30 mjpeg - it's 1080/24 only where I have this problem - and since I don't know how you downrezzed, whether or not you cropped, etc., I really can't say - I am specifically talking about a 1080/24 problem and we would need full resolution grabs with as little or no added compression possible (to the image) in order to check it out.

For what it's worth you have some nice grabs and they are very clean - nice work.
 
I have the same problem as apocalypse.
After I just bought the GH1 and filmed motion pictures in standard avchd settings I noticed immediately the "raw, blurry pixel line" at the bottom of the screen.
It's annoying and catched my eye in a second.
It's true that it is not very noticable on stills taken from moving pics but when you actually see the movie, you'll notice.
I'm not sure yet what to do.
I mailed the Panasonic Helpcenter twice, hoping to get an answer before sending the cam back to the shop for repair.
But almost two months later I am still waiting for an answer :-)
When I read in this forum about the bad experiences with Panasonics' Warranty I'm even more in doubt what to do.
Perhaps I should use different settings than avchd or edit, crop it away, like mentioned earlier, to solve the problem. (Hadn't the time yet to try.)
But I expect from a camera in this price range to work properly.
So I'll let you guys know when it gets fixed if it gets fixed.
 
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dirkjan said:
I have the same problem as apocalypse.
After I just bought the GH1 and filmed motion pictures in standard avchd settings I noticed immediately the "raw, blurry pixel line" at the bottom of the screen.
It's annoying and catched my eye in a second.
It's true that it is not very noticable on stills taken from moving pics but when you actually see the movie, you'll notice.
I'm not sure yet what to do.
I mailed the Panasonic Helpcenter twice, hoping to get an answer before sending the cam back to the shop for repair.
But almost two months later I am still waiting for an answer :-)
When I read in this forum about the bad experiences with Panasonics' Warranty I'm even more in doubt what to do.
Perhaps I should use different settings than avchd or edit, crop it away, like mentioned earlier, to solve the problem. (Hadn't the time yet to try.)
But I expect from a camera in this price range to work properly.
So I'll let you guys know when it gets fixed if it gets fixed.
Click to expand...

That's exactly it - I've gone ahead and kept shooting with it and I'm just cropping off the bottom of the footage.
 
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