Production Switchers

Will the Carbonite (and the router for that matter) be able to handle a PsF23.98 source while it is running in 60i mode?

Hi Kevin,

No you cannot take in 23.98 when in 60i or P modes, this would require 3:2 pulldown and the internal format converters cannot do that.

Routers can pass this format as it is transported in a standard 1.5G HD-SDI stream.

Nigel

#Carbonite

Obviously that's true of a pure 24p signal, however 24 or 23.98PsF is a progressive stream embedded into 60i, thus the question - does the Ross (which does have PsF modes) allow the PsF stream in 60i mode since it is technically a 60i stream with some extra flags and some repeated fields/frames?

#Carbonite

Kevin,

As 23.98 or 24 PsF are split frames that are distributed at a 47.96 or 48Hz vertical sync rate they cannot be supported when the vertical sync rate is set at 59.94 or 60, as it is when running in 60Hz modes. It is not simply a flag setting.

The HD-SDI standard allows the transmission of a variety of frame rates that are incompatible with each other. I can send you some technical documentation on the standards if you are interested.

Nigel

#Carbonite

Huh. I've never heard of a 47.96/48i video system. I was under the impression that 23.98PsF was invented during the early days of editing films at 1080i - that it was used to edit 24fps source material on 60i only edit systems. That's how it was always explained to me and it's how I have used it in the past. I have apparently been operating under a false understanding - I assumed 24 & 30 PsF were embeded in a 60i stream and that 25PsF was embedded in a 50i stream. Is 30PsF in a 60i stream? If so, will it work through the 60i system?

Purely anecdotal - and likely it just involved a quirk of luck - but I have played back from an AJA Ki Pro @ 23.98PsF through a GV Kayak running at 60i and wound up with a picture on screen that was timed out correctly (or at least it never rolled, jumped, or glitched while we switched it that I could ever see). Which was the whole reason I asked - we are getting ready to bring a Carbonite online at my new facility/employer and I was wondering if there was any way to make something like that work. I suppose I'll just come out of my NLE with a 60i file with the pulldown applied - because I really, really want my F35 footage to look as good as it should.

Also, On my phone I couldn't make out the tiny R in your portrait - thanks for the official Ross answer/love. Your company's support is the main reason I picked you over another switcher choice - you know the one that's kinda new and uses some kind of mystical forces to make it work... They didn't answer their phone for a month when I was calling.

#Carbonite

Kevin, to clarify - there is no 47.96/48 video format, but there are two vertical sync pulses for every PsF frame as it is segmented to fit into what was originally an interlace recording format but at a slower frame rate. Your Ki Pro is capable of reformatting 23.98PsF on the output and giving 1080i/59.94, so my guess is the Ki Pro was outputting an acceptable rate for the Kayak.

Glad you chose Ross :)

Nigel

#Carbonite