H1 720p Slow motion clip

[Elton]

I've been trying an experimental procedure to get the equivalent of 60p overcrank slow motion from the XL-H1.

Before I go into the details, please let me apologize for the underexposed clip. It was almost sundown and I just rolled off some footage in the backyard of my sister's house with the kid's jumping around on a trampoline, and I forgot to adjust the brightness of the EVF, so it's a little wonky...color settings were a little off too...but oh well.

Workflow:

--Shot SDI straight to DVCPRO HD 1080i into the Kona card
--brought clip into Compressor and converted to DVCPRO HD 720/60p
--Brought 60p clip into Cinema Tools and conformed to 720/24p
--converted clip in Compressor to 720/24p h.264 @10 mbs

That's it.

Please tell me what you think of the motion rendition

www.homepage.mac.com/mrbarlowelton

[Elton]

Had to take it down.

[jamestmather]

was looking at the clip of the "snowboarder" and was wondering how you got slow mo outdoors - are you carrying your Pc with you?

[Elton]

That was 1080i HDV shot with 1/100th shutter in the late afternoon. Took the tape back to the studio and captured it through the SDI port into DVCPRO HD 1080i (100mbps) codec. Rendered 720 60p from 1080i in Compressor. Conformed to 720 24p in Cinema Tools and thus, the "overcrank".

I don't carry my G5 on my back, I swear!!

[jamestmather]

Forgive my complete boneheaded ignorance but I'm not clear - you shot on HDV and then managed to pull a 100mbs signal off the camcorder via SDI?

Is this better than HDV?

and does it allow for 4.2.2 colour processing?

Otherwise what is the advantage of a 100mbs codec if the footage has been precompressed to tape at a lower compression? or am I missing something?

Thanks for getting back by the way - much appreciated

James

[Elton]

Forgive my complete boneheaded ignorance but I'm not clear - you shot on HDV and then managed to pull a 100mbs signal off the camcorder via SDI?

Well, actually I managed to get a 1.45 Gigabit signal (SDI 1080i spec)...munched down to 100 megabits from originally 25 megabits. How's that for confusing!?

Is this better than HDV?

Yes and no. I know how it sounds, (doesn't make sense) but the oversampling going on with the SDI output might be empty bits, or not, but what I perceive is a little smoother transfer and very clean in DVCPRO HD.

and does it allow for 4.2.2 colour processing?

Otherwise what is the advantage of a 100mbs codec if the footage has been precompressed to tape at a lower compression? or am I missing something?

Thanks for getting back by the way - much appreciated

You're not really getting 4.2.2 from tape...but you can work in a 4.2.2 I-frame codec in post this way. It's just a nice convenience and workaround until FCP offers native 24F support. Again, for greenscreen though...the live SDI output is awesome. Your film was shot in a studio greenscreen situation, right? The H1 tethered to an FCP workstation on a cart would work quite well for your purposes, I think. You can record live 4.2.2 SDI and also roll tape as a backup.


btw, you're welcome and good luck in your decision making.

[starway2001@mac.com]

Actually, the HD-SDI completely bypasses the HDV encoding chipset. So the signal is in fact uncompressed 4:2:2 HD. It's not full raster (1920x1080). But it's definitely HDCAM quality.

[Elton]

Actually, the HD-SDI completely bypasses the HDV encoding chipset. So the signal is in fact uncompressed 4:2:2 HD. It's not full raster (1920x1080). But it's definitely HDCAM quality.

Actually, the uncompressed SDI output IS full raster 1920x1080i. The 1.67 MP CCD's are horizontally pixel shifted to get to that resolution. It's only subsampling to HDV or DVCPRO HD recording formats that loses some of the detail.

That's where working in a format like Cineform is so cool...because it's full raster 10 bit 4.2.2 at a manageable data rate. (15-20MBsec, I think) For FX heavy stuff, it's probably worth investing in.

[starway2001@mac.com]

Ahh. I understand what you were saying now. Sorry 'bout that.

From what I understand the Blackmagic Decklink DVCProHD codecs have been modified to sub-sample at 1440x1080 rather than 1280x1080.

[Elton]

If you shoot PAL H1 stuff, you do get 1440x1080 because that's the 50hz DVCPRO HD spec. 60hz HD is 1280x1080

Both Blackmagic and Kona do it to the spec, I believe

[starway2001@mac.com]

I think Sony's HDCAM 24P spec is 50i.

At any rate, the "get info" on my captured HDCAM footage shows 1440x1080.

[Elton]

That's wild. I've never heard that one. 24P in 60hz countries, I thought, was 24PsF (something akin to pulldown for compatibility reasons, but truly progressive)

Wow, 1440x1080. That's awesome...same rez as HDCAM. Sounds like this might be a great option for SDI capture.

Thanks for the info...

*still scratching head*

[Emanuel]

The 1.67 MP CCD's (...)1.67 MP CCD's?? I know there are the Canon's numbers but at my math it is 1440x1080 = 1,555,200... -- where's my misunderstanding?

[Elton]

Horizontal pixel shift achieves the 1.67MP image.

[Emanuel]

OK But why is this 1.67MP. 1920x1080 isn't it 2,073,600 - why this strange number? I know that HVX must be pixel shifted to 1280x1080 because its 60Hz DVCPRO-HD codec or to 1440x1080@50Hz, as well, as Bob explained the 960x540 of the 1/3" chip it must be counted as 518,400 x 2...

...but in the Canon's case why 1.67MP? What's the advantage? -- if there is

[Elton]

I don't know exactly, Emanuel. If you look at Panasonic's own description of Canon's pixel count, they seem to think it's in the neighborhood of 2K horizontally. You might also be confusing the resolution of recording formats such as DVPRO HD and HDV to the actual 1080i HD-SDI spec.

Whatever it actually is, it seems to achieve a legit 1920x1080 out the SDI spigot.