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Polarjee
09-10-2009, 08:22 PM
Sorry, I know this is definitely a stupid question but I've been doing a TON of research on this camera and I've never been able to figure out exactly what MUD is. I'm guessing it's particles showing up during motion blur? Is it something that I should worry about and could prevent me from buying the camera? And how bad is it? Is there any videos online that demonstrates MUD?

I'm just trying to see if I should wait for the 7D or get the GH1 now.

Thanks!!

BhambuNath
09-10-2009, 08:33 PM
MUD - well now I wonder who coined this term and did it come into existence with GH1 or were there muddy camera blues before too.

Now to answer your question, here's the example of MUD http://www.dvxuser.com/V6/showthread.php?t=182028&page=3&highlight=boobs

You should only worry about MUD if you want to shoot in 1080P with lots of whip pans or vibration as the whip pans are the culprits when it comes to MUD.

720P AVCHD and MJPEG are both MUD free even with whip pans...

Cassius
09-10-2009, 08:34 PM
It's not particles. It makes it look like the image your looking at is viewed through translucent jello. Things get all wavy and weird. Sometimes it looks like the whole picture distorts outward. That's the extreme. The normal ones that show up are slight aberrations that make things look off, but they almost never show up. It's definitely not worth worrying about. That said, the GH1 and 7D are both on backorder, and personally I would expect the 7D to be a better camera. I have no doubt there's a wider selection of non-adapted lenses available. It's also a little spendier, but my point is you'll probably be waiting either way if you plan to order from a retailer.

Polarjee
09-10-2009, 08:38 PM
Oh, I see, that helps a lot!! For what I'm planning to film, I can totally go with 720P but I heard that the GH1 Can only film 30P or 60P in 720. Is that true or can you actually shoot 24P with 720?

Ben_B
09-10-2009, 08:48 PM
It's not particles. It makes it look like the image your looking at is viewed through translucent jello. Things get all wavy and weird. Sometimes it looks like the whole picture distorts outward. That's the extreme. The normal ones that show up are slight aberrations that make things look off, but they almost never show up. It's definitely not worth worrying about. That said, the GH1 and 7D are both on backorder, and personally I would expect the 7D to be a better camera. I have no doubt there's a wider selection of non-adapted lenses available. It's also a little spendier, but my point is you'll probably be waiting either way if you plan to order from a retailer.

That is jello, or, more technically, Rolling Shutter Skew, not mud. Mud is a result of the way the codec records changes (and only changes) made to the image, as seen in the stills that were attached, by dividing the frame into Macroblocks.

I personally think it's an interesting sign that many of the people bashing the GH1 (not saying anyone in this thread is) don't even know what it is they're complaining about.

http://en.wikipedia.org/wiki/Inter_frame
http://en.wikipedia.org/wiki/Inter_frame#Enhanced_Direct.2FSkip_Macroblock
http://en.wikipedia.org/wiki/Macroblocking#Macroblocking
http://en.wikipedia.org/wiki/Microblocking
http://en.wikipedia.org/wiki/Video_compression#Video_quality
http://en.wikipedia.org/wiki/Video_compression_picture_types#Macroblocks
http://en.wikipedia.org/wiki/Motion_compensation

Mud occurs due to complications with recording video in this manner at a lower bitrate when there is excessive motion.

Ozpeter
09-10-2009, 09:00 PM
Mud is when it looks like an impressionist painting. Well, that's how I see it.

Fluke
09-10-2009, 09:06 PM
Mud is when it looks like an impressionist painting. Well, that's how I see it.

Now, if we could only find a way to make the GH1 look muddy all the time, we'd be able to make a very creative looking biopic on Claude Monet and his works, filmed entirely to look like one of his paintings!

John Caballero
09-10-2009, 09:06 PM
I heard that the GH1 Can only film 30P or 60P in 720. Is that true or can you actually shoot 24P with 720?

MJPEG 720=30p
AVCHD 720=60P
AVCHD 1080=24p

In NTSC cameras

If you know what the "mud" is and what causes it in the process of filming you can easily avoid it and get some great images in 1080P.

Polarjee
09-10-2009, 09:17 PM
Awesome! And speaking of frame rates, if I were to shoot in 30fps 720P, I noticed I can only shoot in MJPEG. Is MJPEG acceptable?

Ozpeter
09-10-2009, 09:30 PM
Oh, and jello - I always thought that it was the effect you see more with TV or mpeg2 particularly on faces, where the features tend to slightly kind of wander on the face, like you were wobbling a bowl of jello. But there's every chance I'm wrong on that. Anyone got a name for that 'effect' then?

Ben_B
09-10-2009, 09:35 PM
Oh, and jello - I always thought that it was the effect you see more with TV or mpeg2 particularly on faces, where the features tend to slightly kind of wander on the face, like you were wobbling a bowl of jello. But there's every chance I'm wrong on that. Anyone got a name for that 'effect' then?

http://en.wikipedia.org/wiki/Microblocking

Like this?


Anyway this is Jello in this video with the overexicted narrator:
http://www.panasonic.com/business/provideo/flv/rhc_vids.asp?video=vid9

@1:53 demonstrates skew generally which is sort of like jello. More specifically check 4:15 "a rubbery image with long focal lengths"

Ozpeter
09-10-2009, 09:35 PM
I would expect the 7D to be a better camera.I think it's very important to say "better for such-and-such purpose" or "better in this or that respect". It's not a global thing.

John Caballero
09-10-2009, 09:35 PM
Is MJPEG acceptable?

I've found it very very good. Easier to edit. I wish Panasonic gave it a 24P option.

Ozpeter
09-10-2009, 09:37 PM
Nope, that's not it at all, thanks Ben - the picture looks just fine, nothing breaking up or blocking, just a a kind of wandering effect (maybe caused in flesh tones by inability to resolve subtle differences of colour consistently??)

Imagine you've got a jelly (as we call jello) turned out of its mould in one piece on a plate. You're looking down on it. Wobble the plate gently and the centre at the top tends to wobble more than the outside at the bottom (which is restrained by the plate). It could never be shown in a still (unlike rolling shutter problems or 'mud) because it's only evident when the video is actually running.

Ben_B
09-10-2009, 09:40 PM
Anyway this is Jello in this video with the overexicted narrator:
http://www.panasonic.com/business/provideo/flv/rhc_vids.asp?video=vid9

@1:53 demonstrates skew generally which is sort of like jello. More specifically check 4:15 "a rubbery image with long focal lengths"


Reposting cause got lost when I did edit.

Cassius
09-11-2009, 01:02 AM
I think it's very important to say "better for such-and-such purpose" or "better in this or that respect". It's not a global thing.

I meant it as a global thing, but that's my personal opinion based on past experience with products from either company mixed with personal preference. So it may not apply to everyone, different markets prefer different things. Although thinking on it now I might just be sure of that because I already own so much compatible glass.

And sorry about the wrong answer, thanks for the correction. I get these various issues mixed up easily, especially since I've rarely had them actually show up. In that case I'm pretty sure I've only had jello show up on the GH1 so far.

sammysammy
09-11-2009, 07:44 AM
Ben, if you dont mind i have a dumb question also, the "ghosting" i see sometimes ( i mean here and there on semi fast pans or movement), mostly from shooting in 24p mode, is it just normal thing, or is it me using the setting of the gh1 wrong ..for me mud has not been an issue, maybe im not sure where to look for it, but ghosting has..thanks for your time..

sammysammy
09-11-2009, 07:51 AM
maybe its just motion blur at 24p, maybe its just me..lol..i dont know...

Ben_B
09-11-2009, 07:51 AM
I saw this the other day too...what glass are you using? The one I was had some mild chromatic abberation which may have caused this? Also I don't really see it show up to much on the footage...mainly on the LCD during filming...maybe as result of the refresh rate of the LCD?

Also, if you're shooting 24p are you removing the pulldown?

sammysammy
09-11-2009, 08:05 AM
yes Ben, im using nikon 1.8 and 1.4 and the vivitar 2.8 (for some reason on this one the ghosting is less), but even after pulldown tmpgenc 4.0, i also tried the trial neoscene, i still had some ghosting ( if it is ghosting or maybe just normal motion blur or whatever ,lol), but you had to look hard, the ghosting is much less when i shoot 60p .....

sammysammy
09-11-2009, 08:21 AM
ok, here is a better idea of what I'm seeing, in this clip if you freeze the clip at 2.01 (the lady)
0.23 (the car) , that's what I'm seeing , it could be a normal thing, that's why I'm asking, thanks again

http://www.vimeo.com/6530150

Nitsuj
09-11-2009, 08:54 AM
A good way to get mud on your GH1 is set it for 1080p 1/50 shutter, hit record, then real subtle like run through a thick forest like a mad man. Replay it and there you have it. I should know, I tried it. Hehe.