Gary Adcock
Forum Replies Created
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[walter biscardi] “One of these days our panny rep is going to bring this unit into our shop so we can do a side by side comparison of it and my Sony PVM20L5/1.”
I worked with one for 5 days last month on a location color grading project.
it matched exceptionally well against the BVM D20 I was using as my reference,
liked it so much I have one on order.Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Chad Kappeler] “He’s working with an AJA IO and a 2.0 dual gig G5 with 3 gigs of ram running Tiger and absolutely every update currently available.”
with out the hardware we are lost.’
the green screen when working with the IO usually means the firewire buss cannot handle the bandwidth.
you do not have FW drives and the IO on the same FW bus do you . ( if you have not added a card in the machine the answer is yes)Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Michael Krupnick] “I stand corrected on HDCAM sampling, but actually, DVCProHD IS spec’d at 4:2:2 sampling.”
The Varicam uses DvcproHD, but footage from HDCam converted to DVCPROHD cannot miraculously make the color space better than what the camera captures. I was talking camera format vs compression format.
[Michael Krupnick] “Almost all popular tape formats are compressed to accomodate the huge amount of data in HD. Baseband 1080i/59.94 HD is 1.5 GB/second,”
All HDTV broadcast video signals are 1.5 GBs not just 1080.
[Michael Krupnick] ” The crux of my problem in this thread came from a relatively simple math dilemma: two codeccs both claiming to 1080 lines high and 16X9 aspect had different horizontal dimensions (1920 and 1280). That is not possible even in elementary-school math. “
Thats because your assumption is in error, the 720p version of the HD Broadcast spec is 1280×720. It is NOT a 1080 signal format.
[Michael Krupnick] “The reason that occurred is because Sony and Panasonic differ on what they call a pixel”
No they do not – What we are discussing are 2 different fame sizes for the captured signal
Sony Captures — 1080i (psf)— 1920×1080 (1440×1080 on the tape)
Panasonic Captures –720p — 1280×720 (960×720 on tape)The math for this aspect ratio change is the same.
Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Michael Krupnick] “My assumption was that 4:2:2 samples were counted the same as pixels by Sony and Panasonic.”
That would be great if both formats were 4:2:2-oonly the Varicam captures at 4:2:2
HDCam is 3:1:1 and the HDV camera captures 4:2:0[Michael Krupnick] ” And the fact that these numbers do not (readily) appear in publications of SMPTE or ATSC doesn’t add clarity, either. I naiively just figured that all pixels were equal. When does 1920=1280? When marketing and engineers conspire”
Yes but we are talking about a a huge amount of Data that needs to be laid sown to a very very small track on tape. Think of this “squeezing” of the image in the same way as the old anamorphic lenses for film.
You shot on film and the accessory lens squished the widescreen format to something similar to what you see in the compressed versions of these files. When the footage is projected the lens on the projector would be rotated 90 degrees to “spread” or “expand ” the image back for widescreen playback.Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Michael Krupnick] “Any similar experiences/ideas out there?”
Michael
your settings need to be reset in your seq settings the files you are capturing should not need to be rendered in the timeline
FCP is indeed doing what you told it to do,
YES – 1080 DVCPROHD compressed content is indeed 1280×1440 –think of it as an anamorphic squeeze
Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Francois X] “so “up-converting” a finished looked TIMELINE in FCP from HDV or DVC HD Pro to-> full HD 10 Bits is possible ? but only “software inside codec working ” based ? ? ? “
Francois
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[Jas L.] “But what I meant by true format was that 1920×1080 is prob. the most commonly used format in both theory and practical world.”
Not in my world, not in the US. Possibly on the west coast, but outside of LA- Varicam outsell HDcam units at about 7-1. The world that walter and I live in is capture at 720p deliver 1080.
[Jas L.] “how does 1280×720 on the JVC and 1440 on the Sony “cross convert” to 1920×1080. Isn’t that upconvert. I am definitely missing something here. “
the JVC HDV camera is 720p it does not shoot 1080,
1440 x1080 is the native frame size on HDCAM tape it plays out at 1920×1080HDV was developed as a consumer format – DVCPROHD and HDCAM are professional mastering tape formats –
Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Jerry Hofmann] ” see if you need more.”
IMHO 2 gigs for any HD work is a bare minimum,
remember that you need 1 gig of RAM just to be able to launch FCP for HD work.
In my experience 4 gigs is the sweet spot.Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Jas L.] ” The “true” HD frame is 1920×1080. DVCProHD uses 1280×720. “
Jas –
These is not ONE “true” HD format, there are 14 ATSC specs listed for HD broadcast and they do not even include the older 1920×1035 analog HD format version nor any of the digtal versions from Viper, genisis or other digital capture methods that can be considered HD.The frame size recorded on Sony HDcam is 1440×108, the DVCproHD compressed format for 720p is 960×720 — DVCPROHD is a compression format that also conforms to the 1080 world. All “in Camera” Tape formats do this horizontal squeeze with HD material so they they can get as much info on the smallest possible tape area (and no this does not include HDCam SR– there is not currently a camera that uses has SR as a tape format)
[Jas L.] “So if you like to go to the HD frame rate of 1920, then yes, upconvert would be the answer
The 720 >1080 conversion is always called a cross convertGary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Rick Sebeck] “Is this just normal fields? Again, its not noticeable on an NTSC monitor until you scale, rotate, or move the image or if you take it into AE to rotoscope and such.”
correct these are fields — but the field order looks reversed on the still posted NTSC video on a mac is lower field first.
[Rick Sebeck] “Another thing I noticed is that it happens in a 3:2 cadence. That is, 3 frames are smooth, two frames are like this. Any footage i bring in via the kona uncompressed ha this distortion”
That 3:2 “pulldown” means that the footage was shot at 24p- the extra frames have been added so that the footage plays at 29.97