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joe 1008
05-07-2009, 04:00 PM
I know it's not fair to judge a camera from some footage on the web. But this one is a real aliasing stress test as there are many, many thin horizontal lines and it SEEMS the GH1 didn't pass it well.

http://vimeo.com/groups/gh1/videos/4518762

Any thoughts about this?

Ian-T
05-07-2009, 04:32 PM
Saw this one already. I think the bottom line is it doesn't jump out at you like the aliasing on 5D footage. Plus the second thing is the mode this was shot in. We have learned that if shot in 720p a lot of these issues would be diminished and this does seem like 24p/1080 to me..

squig
05-07-2009, 05:12 PM
these filters are claimed to help reduce aliasing-
http://www.formatt.co.uk/hd-glass-filters/diffusion-refraction-and-enhancing/hd-soft-filter.aspx
http://www.caprockdev.com/antimoire.htm

edit: feedback on tiffen filters for correcting aliasing on the 5D MKII- http://www.dvinfo.net/conf/canon-eos-5d-mk-ii-hd/152702-eos-5d-mk-ii-firmware-update-video-not-coming-4.html

John Caballero
05-07-2009, 05:20 PM
But this one is a real aliasing stress test as there are many, many thin horizontal lines and it SEEMS the GH1 didn't pass it well.

My HVX 200 has aliasing too.

This footage looks pretty good considering the compression on Vimeo. We have to learn to take the good with the bad and avoid situations in which the camera won't perform to its best. The again if you have to shoot in conditions that may give trouble with aliasing then this is not the camera for you.

This footage has a brick wall in the background, notorious for giving aliasing trouble, and it looks pretty good:


http://www.youtube.com/watch?v=uTlCp...eature=channel (http://www.youtube.com/watch?v=uTlCpY06oDo&feature=channel)

http://www.youtube.com/watch?v=qFIFh...eature=channel (http://www.youtube.com/watch?v=qFIFhnVou48&feature=channel)

Ian-T
05-07-2009, 05:24 PM
This footage has a brick wall in the background, notorious for giving aliasing trouble, and it looks pretty good:


http://www.youtube.com/watch?v=uTlCp...eature=channel (http://www.youtube.com/watch?v=uTlCpY06oDo&feature=channel)

http://www.youtube.com/watch?v=qFIFh...eature=channel (http://www.youtube.com/watch?v=qFIFhnVou48&feature=channel)And judging by the ghosting I seen in that first one I can tell it was shot in 24p without pulldown removed. And surprisingly...it looked dang good.

ryansheffer
05-07-2009, 05:24 PM
Not having aliasing would be ideal. But in terms of price. Even the Ex-3 suffers from some pretty bad aliasing. It was all over this documentary I edited.

John Caballero
05-07-2009, 05:31 PM
And judging by the ghosting I seen in that first one I can tell it was shot in 24p without pulldown removed. And surprisingly...it looked dang good.


Yeah, but that is really no problem. People are having trouble with that because they are new to it. But thats nothing major. My HVX 200 in DV has horrendous aliasing. Not as much in the other modes but its still there.

Ian-T
05-07-2009, 05:36 PM
I think the 24p will be great for scenes like the first take and even the second one... When your scene calls for lots of action and slow motion then 720p will be ideal. This shows the versatility of this cam... At least that is how I plan on using it. Also...background blur will help with 24p. The picture is certainly sharp enough...but blurring out the background I think will be a heck of a lot easier on the compression. I have no issues with the aliasing I've seen from this cam. It is not distracting to me.

John Caballero
05-07-2009, 05:42 PM
I think aliasing shows more on the wide angle shots. Maybe I am wrong but thats what I see in the DV footage from the HVX 200. Once you zoom in more is not as bad.

squig
05-07-2009, 05:46 PM
yeah Kholi said it's more prominent wide

I just added some filters to my post above.

Ian-T
05-07-2009, 05:48 PM
That makes sense. It seems to me the sharper the image...the more prone to aliasing you are. SO when you are wide...I guess sharpness would be at its peak...and the more and more you zoom in the picture naturally gets a little softer and softer. At least this is the sort of thing I experience on my HV20.

John Caballero
05-07-2009, 05:52 PM
I guess that means we have to be very careful when we shoot wide. I can't wait to get my GH1 and start messing around with it and see the results.

Ian-T
05-07-2009, 05:56 PM
He he...I guess June can't get here quick enough for some of us.

John Caballero
05-07-2009, 06:03 PM
Yep! Its like Christmas in June!

joe 1008
05-08-2009, 08:15 AM
Saw this one already. I think the bottom line is it doesn't jump out at you like the aliasing on 5D footage. Plus the second thing is the mode this was shot in. We have learned that if shot in 720p a lot of these issues would be diminished and this does seem like 24p/1080 to me..

720p seems to be more and more the sweetspot of this camera: Less alaiasing, almost no rolling shutter. Would be interesting to compare the GH1 resolution at 720p to a HVX at 1080p. Given the reduced number of pixels in DVCPO-HD it could be equal - at least in theory.