A1 Steak Sauce
 

I just had to make that title :)

2 questions

1. What are the chances that there will be an updated A1 in the next year or so that will include more variable frame rates? Like the HVX200?


And also, I've done a little searching and I just get more confused about the capabilites of the A1 and a green screen. I saw several posts that said the color sampling on the A1 is 4:2:0

But straight off of the canon website, this is what it says "The XH A1 has an output with 4:2:2 color sampling which ensures optimal image quality" ....Ok so whats going on? ....And has anyone actually tested the A1 with a green screen and have anything to say about it? or footage to share?

Thanks,

John

Scott Billups tested the H1 vs. the Cinealta and said the Canon keys better than the Sony. I'd assume the A1 is very close to that.

Jim Martin
Birns & Sawyer

Which Cinealta?

Via analog component video output.

If you plan on shooting progressive scan then the 4:2:0 is actually not that bad at all.

True progressive 4:2:0 is very clean are basically just has chroam pixels that are the size of 2x2 pixels. This is much cleaner then 4:1:1 because with 4:1:1 you have a chroma pixel that is the size of 4x1 pixels. This means huge holes in the horizontal direction that can be 4 pixels wide. P 4:2:0 is a nice even value that gives very clean results.

Interlaced on the other hand uses 4:2:0 in a different way and has to alternate the vertical samples every other line. This can create a mess if not dealt with well.

What if you are capturing through DV? Will it downsample it to 4:2:0 or 4:1:1:? Even if shot in HD at 24F?

HD output over FireWire (which is compressed digital) is 4:2:0.

HD output over Component (which is uncompressed analog) is 4:2:2.

Frame rate has no bearing on this. Keep in mind that component video capture does not include audio output... but digital capture by FireWire does.

I've been playing around with my A1 and green screen and it seems to look pretty good to me. I don't have any other camera to compare it to but as long as I light the screen right (that seems to be the hard part for me) It looks pretty good. I'll try to post a clip for you because after all someone with more experience than me might think it looks like crap.