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Caesar
11-30-2009, 07:55 AM
How have you GH1 users experienced the aliasing?

Mattsan
11-30-2009, 08:07 AM
HG1 is better than 7D in 720p mode hands down.

Martti Ekstrand
11-30-2009, 08:22 AM
It's there, as can be seen on Barry Green's trumpet chart test, but since it has very little colour artifacts it's rather benign, no green-purple blotching along horizontal edges or pattern psychedelia - nothing yet has forced me to do anything in post about it.

Barry_Green
11-30-2009, 11:12 AM
All the DSLRs show substantial aliasing. As Martti says, the GH1's is less noticeable because it doesn't introduce the rainbow color artifacts that the 7D/5D do. But in terms of making moire patterns, there's just as much there. So you have to spend just as much effort trying to defeat it.

With that said, we had a user here post a video off the GH1 that contained perhaps the most shocking example of real-world aliasing I've ever seen, and nobody who viewed the video even commented on it, so -- your mileage may vary.

Ozpeter
11-30-2009, 01:13 PM
People can be surprisingly uncritical of posted video - for instance, in one which was the centre of much 'mud' discussion some months back, my reaction to what was shown was to wonder why the dissatisfied owner was complaining of mud when they hadn't properly focussed the subject in the first place, which seemed to me to be a more serious problem... but nobody commented on that. Perhaps we're all too polite?!

Gordon Prince
11-30-2009, 03:31 PM
With that said, we had a user here post a video off the GH1 that contained perhaps the most shocking example of real-world aliasing I've ever seen, and nobody who viewed the video even commented on it, so -- your mileage may vary.Do you have a link?

Mattsan
11-30-2009, 03:53 PM
you gotta be careful of posted vids - a lot depends on the final render so what you see may not be what the camera produced!

I am more than happy with the lack of any stepping on high contrasting areas with the GH1 - to me its a non issue (compared with other issues the cam has)

Barry_Green
11-30-2009, 05:37 PM
Do you have a link?
http://www.dvxuser.com/V6/showthread.php?t=191442

Barry_Green
11-30-2009, 05:38 PM
you gotta be careful of posted vids - a lot depends on the final render so what you see may not be what the camera produced!
Very, very true. I don't know if the camera caused the issue, or the youtube resize, or whatever. I was just surprised nobody even mentioned it.

snicky
12-01-2009, 12:52 AM
Btw: have you guys ever had any problem like this: http://www.dvxuser.com/V6/showthread.php?t=191252 ?

Mattsan
12-01-2009, 02:57 AM
Ive tried Neoscene and decided it was rubbish - I use Edius' free AVC 2 HQ utility for my conversions - it does a great a job. (free with Edius NLE s/w)

I encode all my footage to MPEG-2 @ 35mbs constant - then from the NLE I output in exactly the same format with smart render - not only is it fast to work with and make a final render, its also in a format ready to be burned straight to BluRay without any futher encoding - to me the results are as good as what the camera produced without any visible degridation of quality.

It's the fastest workflow I've managed to muster.

snicky
12-01-2009, 07:06 AM
Hey Mattsan, is this utility able to remove pulldown properly? Im using TMPGEnc right now, but it's a bit slow comparing to Neoscene :(

Mattsan
12-01-2009, 07:11 AM
~I dont have to worry about that, my NLE does that anyway if you select the correct project preset. But here is a screen shot of the little utility which has the option to remove it.

Caesar
12-04-2009, 06:30 PM
HG1 is better than 7D in 720p mode hands down.Thanks. As matter of fact, I'd rather know as far as the 1080p concerns too.

JackBayer
12-05-2009, 09:01 PM
Ive tried Neoscene and decided it was rubbish - I use Edius' free AVC 2 HQ utility for my conversions - it does a great a job. (free with Edius NLE s/w)


Hi!

would you please care to elaborate on what is rubbish with neoscene please? I use it and I never had any problems but Im always willing to learn.

I loved Edius btw, when I had it a few years ago...

Mattsan
12-06-2009, 04:42 AM
I just wasnt happy with the transcoded file's quality - I felt it was not as sharp as the original footage (plus it was slow to process the files)

This is my personal opinion and not scientifically judged.

Compare cineform output with the edius output and you too might be surprised

philiplipetz
12-06-2009, 08:11 AM
I just wasnt happy with the transcoded file's quality - I felt it was not as sharp as the original footage (plus it was slow to process the files)

This is my personal opinion and not scientifically judged.

Compare cineform output with the edius output and you too might be surprised

If you are using the Mac version you can choose between cineform files (slow to process in some NLEs) and ProRes which is faster to process. If you are referring to time to transcode then you are stuck with the time but there is a real difference in NLEs like Final Cut handle the two formats.

Also, there is a recent update to NeoScene.

RandyQ
12-06-2009, 05:54 PM
All the DSLRs show substantial aliasing. As Martti says, the GH1's is less noticeable because it doesn't introduce the rainbow color artifacts that the 7D/5D do...we had a user here post a video off the GH1 that contained perhaps the most shocking example of real-world aliasing I've ever seen

Checked out the vid- you're right, Barry, I didn't see the aliasing the first time I watched this video! I guess I'm one of those who dont notice these things (which is embarassing since I've been shooting professionally for 20 years).

I'm wondering if this was shot on 1080P? Or if it is possible to SEE the aliasing on the LCD monitor during the shoot? If you can see it, then at least we can take steps to avoid it.

Barry_Green
12-06-2009, 08:39 PM
No, in fact, the LCD might show aliasing where there isn't any in the footage. The only way to know whether you've got visible aliasing artifacts in your footage is to watch it at native resolution.

Osslund
12-07-2009, 12:28 AM
It's always best to have a laptop nearby so you can check samples of the footage to determine how it will turn out. The LCD is not a reference monitor.

snicky
12-07-2009, 12:41 AM
Hi!

would you please care to elaborate on what is rubbish with neoscene please? I use it and I never had any problems but Im always willing to learn.

Once again, this looks like a total crap to me: http://www.dvxuser.com/V6/showthread.php?t=191252

That's AVCHD taken straight from the GH1 and transcoded to CineForm AVI :/

Chris Light
12-07-2009, 12:57 AM
what were your settings in those shots?

snicky
12-08-2009, 07:18 PM
Hey skinny, sorry for multiposting. I just thought nobody read that. I posted the settings in my topic.

GMC
12-09-2009, 08:49 AM
~I dont have to worry about that, my NLE does that anyway if you select the correct project preset. But here is a screen shot of the little utility which has the option to remove it.

Dear Mattsan,

I am heavily interested in that workflow as I work with Edius and the AVC2HQ converter nearly every day. So far I couldn't get neither AVC2HQ nor Edius to make a correct pulldown of the 1080i60 wrapper to 24p.

Are you shure you tested the AVC2HQ with the GH1 NTSC version? Or are you talking about the PAL version (which doesn't require pulldown).

What I have tested so far with AVC2HQ is both the Canopus HQ and MPEG 2 conversion with the 1080i60 stream.

If I dump this material in a 1080p23.976 timeline Edius takes the correct frames from the 60i stream (but these contain only half the resolution vertically) and interpolates them to full - rez progressive frames. Hence, the timewise sequence (i.e. movement in the frame) is correct but the resolution vertically is only half. I use a fullHD monitor, only here you can see the difference.

For this reason I am using VoltaicHD - this gives you 1080p23.98 Windows media files with full resolution and correct pulldown.

I would very much prefer a Canopus HQ workflow (very fast!) with AVC2HQ - but as far as I have tried it I couldn't get it to work properly.

The screengrabs you posted suggest that you don't do any pulldown with AVC2HQ - what project settings are you using in Edius? Have you checked on a full HD screen that your workflow is correct?

best regards, Gunther