Panasonic HDX900 or HPC2000

[Gary Adcock]

[Chris Oben] “I only posted the comment to clarify that the F900 does indeed record 24PsF directly to tape on-board not exclusively to D-5 or SRW as suggested by Gary”

Actually Chris there is a very big difference between the true P format I was referring to and the Psf format you are referring to. True progressive images will not play back properly at 48i as your psf format images do.

As far as I know there is no camera that does record a true 24P data to a tape in camera. Sony’s 24Psf is a compromise so that sony decks would still be able to support the older tape formats. as you know the format is recorded as a progressive file but laid to tape and played back as interlace

Great work on the 4400 also I tivo it every week.

I also want to agree with JS’s comments– I do not know of many post houses that handle video at 24.0 as a frame rate unless they are matching film. As john pointed out the post workflow is a NIGHTMARE at 24.0 for most productions.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL

[Chris Oben]

[gary adcock] “As john pointed out the post workflow is a NIGHTMARE at 24.0 for most productions. “

Gary,

I guess I just don’t see the ‘nightmare’. If one gains the ability to shoot without HMI and fluorescent flicker issues by simply changing the frame rate, then why not shoot 24PsF? Am I missing something?

Chris M. Oben

[Gary Adcock]

[Chris Oben] “I guess I just don’t see the ‘nightmare’. If one gains the ability to shoot without HMI and fluorescent flicker issues by simply changing the frame rate, then why not shoot 24PsF? Am I missing something?”

Chris
IMHO you used what worked for your setup- this is not the norm fro this type of work, but do you really think that shooting at 24.0 then slowing down the tape 1% for the submasters is really that different than just shooting at 23.98? If it works in your workflow great. Many of us use these workarounds all the time.

I do know of all of the post projects I have been associated do not use your workflow even when originating on film. At NAB the HD Filmout Session I hosted the UNIVERSAL answer for posting for both HD and film was to work at 23.976 ONLY- the panelists included people from Kodak, Laser Pacific, 24P Entertainment, PlasterCity Post and myself.
Not one individual on the panel supported the 24.0 workflow and everyone of us was adamant that the most serious issue was the audio post process expense when a 24.0 master was used and not a 23.976 ( 23.98)

I am not telling you what you are doing is wrong. However it is not the post process that most people are using in HD. Even the HVX200’s you are using to shoot with do not do any thin but 23.98.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL

[John Sharaf]

Chris,

Since this issue can up on this thread I have asked all the experts I could find (and it was quite convenient to do so yesterday ay Cine Gear Expo here in LA) about the HMI flicker “problem” of shooting 23.98 with magnetic ballasts, and to a person everyone thinks that there should be no problem; unless you’re working with some extreme shutter angle!

I wish I still had a magnetic ballast to test conclusively this theory, but all my HMI’s have solid state ballasts. Is there someone out there who can test this conclusively?

Chris, can you confirm to us that this “problem” was a result of real world experience or just a theory?

Thanks,

JS

[Gary Adcock]

Chris

let me add that this is also a long ongoing discussion on this topic in the CML 2K-444 list. Both John and I have posted as part of that thread also. it is called [cml-2k-444] 24 or 23.98?

it has a number of prominent post people from all over the world talking about these issues and how they relate to 24. 25, 23.98 and 29.97 workflows and the pro’s and con’s of all of them.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL

[Chris Oben]

JS and Gary,

I am interested that no one at CineGear was able to confirm what we have battled since the onset of our use of HD acquisition for dramatic television. Magnetic ballast HMI fluctuation and fluorescent ballast flicker have definitely been a real world problem. When shooting 23.98(23.976) we were regularly forced to use a 1/60th shutter or ECS to compensate for highly visible flicker and fluctuation. The problem was most evident in static shots or long takes with brightly lit walls or surfaces – I also experienced some color cycling where an image would shift from well balanced to greenish and back over a period of about 7 or 8 seconds.

When the first f900’s were put to use in series TV everyone (engineers, D.P.s, sound recordists and post) agreed that 23.98(23.976) was the optimal choice of frame rate. i.e. simplest production / post-workflow. The thinking was ‘let’s shoot 23.98 and record sound at 29.97 thereby preserving the original frame rate as closely as possible without the need for ‘slowing down’ in post.

What we now know is that there are many situations where available fluorescents and magnetic ballast HMI’s cause problems with flicker and/or color cycling which aren’t immediately apparent.

Our solution on “Muppets Wizard of Oz” and “The 4400” is to shoot 24PsF and ask sound to record at 30FPS. At least 4 other local, Panavision supplied TV series are shooting 24PsF including “Stargate SG-1 and Atlantis”.

BTW – when we use the HVX200 for sound sync scenes we ask sound to run at 29.97FPS . . . so far so good.

Gary, Yes there are some very good posts on CML – here’s an excerpt from a thread that I think is valuable:

*** If you set up an F900 in front of a face lit with HMI light and shoot at 23.98 (1/48th) you will see a (cyclical) phase shift in the flesh tones. This is easy to see on a vector scope. The same effect is in evidence with fluorescent sources.

This is *not* a source related issue.

What is more difficult to specify is the degree to which this bothers people.

>

[John Sharaf]

Chris,

I don’t doubt that you had a problem with flickering, but I do find it strange that your HVX200 at 23.98 doesn’t. Furthermore, the fluorescents, if they’re Kino Flos, are solid state and from my own experience can attest to their stability at the 23.98 frame rate.

So this pretty much leaves the magnetic HMI issue; was it all the units, some units, a particular unit? Can you vouch for the stability of the power?

I have to also look at the F900’s in this scenario; I’ve found that auto knee has a tendency to “seek” and that could also be described as “flicker” in the highlights, although not overall in the picture.

This is a very interesting almost esoteric problem, but I have to think that if it were universal, others would have noticed it too. Could it be that magnetic ballasts have become such a rarity that your problem is so unique? I for one have not owned a magnetic ballast for at least ten years and have an inventory of almost forty HMI’s.

I know I used magnetic ballasts for many years with NTSC video running at 59.94, and that certainly is not a speed divisable by twenty and thus a “safe” speed in the HMI window; by your evidence those pictures should have flickered too.

I’m motivated to seek out a magnetic unit and test this out. I’ll let you know what I discover.

Regards,

John Sharaf

[Gary Adcock]

[Chris Oben] “I am interested that no one at CineGear was able to confirm what we have battled since the onset of our use of HD acquisition for dramatic television.”

I am not surprised that you could not find confirmation, I walked around the show and talked with a couple of companies about this and all of the people I talked to mirror the opinion that John and I have been talking about.

I do not doubt that you had an issue in your production, but I can assure you that the vast majority of HD production I have come in contact with is just not done at the 24.0 frame rate, not in LA, not in NYC, not in Chicago.

I also want to note that I am not a DP. I am a post supervisor, so I am not the one to talk about your ballast problem, but telling us about your f900 issues in the Varicam forum re-enforces why many people like John and I are recommending/ specifying Varicam in-spite of the perception that they are ” not as good as the Cine Alta’s”

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL