D800

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I just invented a comical quotable scenario in honor of all this RAW talk.
Boy to his mother. "Mommy. Where does the extraneous data from compression of RAW data files for storage onto solid state media, go when it dies?"
Mother to her son "Honey. I'm not sure but maybe it goes to the lost data center in another universe."
 
I will correct my own mistake/oversight...

eteam said:
The same compressor is used for 'normal' h.264 encoding and the ALL-I form of h.264 encoding. There might be some difference in image quality, but it should be slight. ALL-I encoding (no B or P frames) does not -- in and of itself -- affect compression quality.
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ALL-I removes decoding (and compression) dependencies from one frame to any others. Intra-frame compression means that any sensitivities to motion are eliminated (there is no motion in the context of a single frame). With conventional I/B/P compression, lots of motion will drive the bitrate up to maintain the same image quality. If bitrate is constrained to a certain limit, motion will tend to decrease image quality in order to stay withiin the bitrate limits.

So I was wrong. With plenty of motion, the normal compression will suffer and the ALL-I compressor will not be affected in the slightest. There can be (and will be) IQ differences between the two compression schemes.

-- Bob Elkind
 
* indeed, all-I is not any better in and of itself: if bitrate is not sufficiently increased, it will actually look worse; we'll learn about this empirically
* I'm not sure the Canon compressor is constant bitrate; if IPB is constant quantitizer, increased motion in the images would lead to higher bitrate, and no quality loss, right?
* I'd vote for RAW meaning "information directly out of the sensor, not debayered", and raw meaning "unaltered file"
 
Samuel H said:
* indeed, all-I is not any better in and of itself: if bitrate is not sufficiently increased, it will actually look worse; we'll learn about this empirically
* I'm not sure the Canon compressor is constant bitrate; if IPB is constant quantitizer, increased motion in the images would lead to higher bitrate, and no quality loss, right?
* I'd vote for RAW meaning "information directly out of the sensor, not debayered", and raw meaning "unaltered file"
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I have heard that the Canon All-I is using variable bitrate up to about 90 mbs, but I can't find any definitive sources to that right now.
 
Uwe Lansing said:
Bah, please take a look at this: http://www.youtube.com/watch?v=6ZeM9ofnm4I At first I thought this ugly aliasing/moire will only appear at 720p but this is internal 1080p24. And uncompressed HDMI seems also not better: http://www.youtube.com/watch?v=mGuC5pEWIGg Very disappointing...
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Okay, somone is going to have to point out the aliasing to me. At 0:15 I see some rainbowing on one on the small windows above the arches, but that's it. I watched the uncompressed link at 1080P on two different two 1920 X 1200 monitors that window to 1920 X 1080.

I studied the bricks on the ground and the building and saw no aliasing.
 
I'm leaning more and more towards the D4. What I´ve seen so far shows soft images but really filmic and nicely downsampled so there is no aliasing. The D800 moire and aliasing artifacts are there in every shot and I don´t think I could stand them for too long.
 
I believe you're seeing moire and aliasing but I'm really not seeing it. Can you provide a link w/ a timecode for what you're seeing w/ D800?
 
macgregor said:
meeeeh not a fan of putting a new AA filter in the camera given all the downsides you have to deal with...
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Have you seen the 5DII samples of the filter posted on EOSHD? The results really are impressive. And with the extra detail of the D800 and the lack of rolling shutter issues, it could turn out a really solid result.
 
Grug said:
Have you seen the 5DII samples of the filter posted on EOSHD? The results really are impressive. And with the extra detail of the D800 and the lack of rolling shutter issues, it could turn out a really solid result.
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Well if the price makes sense and the wide angle lenses work fine... why not!?
 
macgregor said:
All posted clips have moire. Point me one that doesn´t. ;D
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How about this one: http://vimeo.com/38912704 ?

I see a little on the door frame in the beginning and on the circular fencing surrounding the trees at the end. But it's really minimal IMHO. But perhaps you're seeing something that I'm missing. In which case, please tell me what and when. Thanks.
 
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here is another two clips i found in vimeo
one is the D4 in the "best" sharpest crop mode 2.7x as users are claiming - https://vimeo.com/39168418
and D800 simple test but effective i think to see how it deals with textures and small detail -
https://vimeo.com/39243878

if someone here owns the two (D4 and the D800 ), PLEASE PLEASE , im begging you do a proper side by side comparison so we can stop guessing how they perform
 
I think it's pretty clear that the D4 is significantly softer. It's so marked, that it feels like the difference between 720P and 1080P. JMHO.
 
BobbyMurcerFan said:
I think it's pretty clear that the D4 is significantly softer. It's so marked, that it feels like the difference between 720P and 1080P. JMHO.
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im sorry but its not clear to me , it will only be clear that D4 is indeed softer when a proper side by side comparison will be made , ( the only thing i can say i noticed is no alaising no moire and no line skipping in the d4 video ive seen so far , which i can see all three in d800 (look here with this amateur video test http://www.youtube.com/watch?v=ey8el-YcvgA&feature=related , alaising and line skipping is especially apparent )
in those three D4 video which i have no idea what crop factor have been used , it doesnt look at all that soft to me -
http://vimeo.com/35639074
http://vimeo.com/38752046
http://vimeo.com/38738219
so i'm still waiting for a decent comparison , hope it will come soon
 
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