Erkki Halkka

Yep - other than the sound stuff, the only important omission (IMO) is black stretch, which helps FX1 a bit in contrasty situations.

It will look better, if you scale to an uncompressed SD format - how big the diffrence is depends on the footage. Wether it's worth of the extra step or not - i.e. for bluescreen work it's DEFINITELY worth it, for something like a documentary (not much post) it's maybe not. You can do the conversion in the camera if you wish, but you'll end up with a regular DV file, and there's probably no big difference compared to shooting DV right away.

We mastered at 720p in-house, but the stuff that went to TV channels for broadcast was SD-PAL. We could have worked directly in SD resolution for the post (as we did with our next vid - which is still unreleased), but the band wanted to add a 720p HD wmv file to their DVD. The reason for using 720 instead of 1080 as the resolution of choice was twofold: first of all, we were able to slightly zoom in the images without making it look too different from the rest of the footage, second of all, 720 has half less pixels to render and store etc. than 1080. The video wasn't originally intended to be shown in 1080 HD, we made the blowup just for HDFEST. A friend of mine saw it in LA screening, and said that some of the shots did look a little soft, but most were surprisingly OK even in the big screen - would have been cool to see it like that ;-) Edit: added a little to the above sentence After being scaled to SD resolution, HDV has better color sampling than i.e. DigiBeta - it's basicly equal to 4:4:4 for NTSC, and 4:3,75:3,75 for PAL. There are some (very) minor artifacts visible after scaling, which can be filtered out to the extent of being nonexistant. With bluescreen, i wouldn't really suggest using HDV on anything higher than SD - but with greenscreen, one can get decent results even at full 1080 HD resolution, if everything goes more or less perfectly all the way from the shoot to post. When scaled to 720 HD in post, there's already more leeway - the effective color sampling should be close to 4:2:2.

Uh, HDR-FX1.

Hi, and sorry for the delay with my reply - This was an all greenscreen project, the backdrops are all 3D. We shot with HDR-Z1, without any adapters or filters. The additional DOF was done in post, by blurring the backgrounds (and, in some cases, selectively blurring the FG too).

As far as i know, HDV is 4:2:0. I've got a web page on the differences of HD formats too - here: http://www.kolumbus.fi/erkki.halkka/HDform...HD_formats.html

I could send you audio test files with 8kHz and 44kHz sampling, where you probably couldn't hear the difference (say, a bass track without much treble in it). That doesn't mean there are no differences in other cases. As said many times before, the difference doesn't show much in all pictures. On yours, the red logo on the hat is the best candidate for seeing color sampling errors - and it in fact does look a tiny bit mushier on the 4:1:1 image. If you zoom into the logo and A/B compare the images, you can see the difference. But it's very, very small in this case. Try making red text over black background, at 4:4:4, 4:2:2 and 4:1:1. Or look at the examples i posted earlier, to see the color sampling differences better. That red hat artifacting shot i posted is a direct .png screen grab from PAL MiniDV footage i shot on vacation, with the enlarged portion done in photoshop. It's actually 4:2:0 - but 4:1:1 should look rather similar. All the color sampling examples with text were made by creating a title in SonyVegas, saving that to various formats (Uncomp, DV, DVCPro50, HDV) and then taking a direct .png screen grab of those. The heading of the page is "Steppy Edges" - more or less exactly the same thing as the "blocky colors" we've been talking about... He's trying to get rid of it by filtering - i use more or less the same methods if i need to reduce color sampling errors when doing keying work, or mastering in higer sampling formats with DV/HDV footage. Instead of just blurring the color channels, i prefer median filtering - it gives slightly sharper edges. As said before, on most raw footage, the difference isn't big enough to be worried about - if it was, low color sampling wouldn't be used. The problem raises it's ugly head with original footage IN SOME CASES, and quite a lot more often, if the footage is manipulated a lot (color correcting individual colors, keying etc.). I too have a page about keying compressed / low color sampling video, have a looksee: http://www.kolumbus.fi/erkki.halkka/HDVKey...and_keying.html

Even if the above was true (if you weren't wrong about how color spaces work making your point 100% moot), you'd still be wrong. See the above gradient. The top portion of it uses 64 shades (same as 7 bit), the bottom portion uses 128 shades (8 bit). Unless you have a very bad monitor, you should see banding only in the top half of the image, because there's not enough shades to show the gradient properly. If your monitor is bad, both show banding.

I don't think it's necessarily about the higher than 22K frequencies - it's about the high but hearable frequencies (near 20kHz) having too few samples for each wave length, causing distortion. 4:4:4 - 4:2:2 - 4:1:1 is analogue to 96, 44 and 22 kHz audio sampling... you can't always hear the difference between 96 kHz and 22 kHz sound, but sometimes you do. It totally depends on the source. As far as mp3's go - 128 Kbit sounds usully rather OK. But in SOME cases... That said, i've destroyed my hearing by playing in rock bands in the 80's, i couldn't hear the difference at all - hasn't stopped me from mixing stuff for video though, i just need a pair of good ears to come and check the mixes for me in case of nasty errors in the high end ;-)

Charlie, you've totally misunderstood this 4:4:4 / 4:1:1 color space thing. 4:1:1 has exactly the same amount of color SHADES asd 4:4:4 - the amount of available colors depends on bit depth, not chroma sampling. Lower chroma sampling reduces SPATIAL chroma resolution, giving blocky images. In 4:1:1, color is saved at only 1/4 resolution - or in other words, color information is saved only for each 4th pixel. It's not much different than sampling audio: sampling resolution tells how many samples are taken (i.e. 48 000 samples of audio / second - every pixel of luminosity channel [4] and every 2nd pixel of both color channels [2:2] in 4:2:2 color sampling), bit depth tells how many diffrent levels those samples can be at (256 colors / channel in 24 bit RGB images or 256 audio levels at 8 bit audio). I.e 4:2:2 could just as well be marked as 1:1/2:1/2. If you have i.e. 100*500 pixel image, you'll get 4:4:4 1000*500 luminosity resolution 1000*500 color resolution 4:2:2 1000*500 luminosity resolution 500*500 color resolution 4:1:1 1000*500 luminosity resolution 500*250 color resolution Please, have a look at this image again, it shows the artifacts well. http://eki.pp.fi/temp/Eki/ColorSampling/Madeira_411.png So does this: http://eki.pp.fi/temp/MiniDV_uncomp_from_HDV.png

...it might also be interesting to know how much experience with HDV the participants have. So, how many of us here has shot HDV? Done post on it? Worked on HDV to film project(s)? Seen HDV to 35mm print footage in a theater? "Yes" to all accounts here ;-)

I wouldn't feel comfortable operating due to lack of experience, but if someone else operated the camera for me, and/or offered a bit of backup when making technical decisions, i'd be happy to give it a try.

Shoot 35mm film as DOP: No. Direct stuff shot on 35mm film: Yes. Done post production / color timing with telecined film: Yes. Done post production / color timing with 2K film scans: Yes. Been in telecine: Yes. In one of the 10 big post houses: Not in U.S.A. - Yes in Finland.

I use it a lot, when i need to give "film look" finish to video or CGI. The beauty of it is that it uses actual film grain. The grain looks real simply because it IS real. I have a small collection of digitized film grain, or more accurately, black footage from film transfers, i.e. the beginning of an archive film, or a telecine session. I simply put these on top of video in additive or screen transfer mode mode. It works pretty well. I control the amount of grain by color correcting the grain layer - more contrast = more grain. Shooting a gray card so that it's exposed to 50% luminosity, and compositing that in overlay mode would be theorethically slightly better method. In my "black" method, the grain always lightens the image. With "gray" method, some of the grain lightens, some darkens the image - dunno how much that matters in real life ,-) I was just referring to technical quality... that has been out of the reach untill now. That said, there's places outside Hollywood... usually they too work in the same way though ;-)

That pretty much sums it up, i think ;-)