multiple resolutions and framerates

[Mohammad Farooqi]

Hey guys,

Just wondering if there are any plans to add the ability to record multiple framerates and resolutions on the the same cf card with the flash xdr, similar to how the sony sxs cards work.

Thanks

[Dan Keaton]

Dear Mr. Farooqi,

Short Answer: We can do this now.

Long Answer:

It is currently possible to record any frame rate / resolution / file type (Quicktime or MXF), etc. on one card.

However, we normally recommend against this practice for the following reason.

We break large files up into smaller files. This is typically transparent to the user during playback, and this allows us to seamless record from one card to the next and work with both Mac's and PC's.

Thus, during playback, we instantly advance from one file to the next, seamlessly, so that playback proceeds from one file to another.

However, if one file is 1080p24, and the next is 720p60, for example, there will be a glitch in the playback as these are different standards and it takes time for us to adjust to the new playback standard.

So, if one records multiple standards, frame rates, etc. on a card, everything if fine when:

1. The files are uploaded to a Non-Linear Editor (NLE).

or

2. The files are played back, individually, or in sequence, until there is a change in file standard, type, etc.

We have a "Play" menu, which allows one to select which file to playback.

Once a file is selected for playback, we will continue playing back from one file to the next, or until playback is stopped, or the playback is paused.

If there are multiple standards on one card, just select the file you wish to playback, and everything will be played back properly (until we reach a file that is recorded in a different standard, and then there will be a glitch.)

Minor changes in standard or mode have no effect. For example, recording in 50 Mbps, then changing to 100/140/160/220 Mbps, is ok (as I currently understand it).

Changing from Long-GOP to I-Frame Only or vice-versa, is also ok (as I currently understand it).

Changing from 4:2:2 to 4:2:0 will probably cause a glitch (but I am not positive).

Changing from 1080i to 1080p will probably cause a glitch (but I am not positive).

Changing from 1080 to 720 will cause a glitch.

Please understand that each file is recorded intact, according to the standard, frame-rate, mode, file type, etc., as choosen by the user via the menu system.

Each and every one of these recordings will be perfect when transferred into your NLE.

We just can't maintain perfect glitch-free playback, on-the-fly, as we switch from one standard to another. If we start playback on any given file, we will playback the file in the proper format.

So, overall, while we can record mulltiple file standards, bit-rates, file types, modes, etc. on one card, it is just easier to recommend that one use separate cards for different standards, then all playback will be glitch free.

[Rafael Amador]

Great to hear this.
I guess was a concern for everybody the idea of not being able to change standards in a same shooting. I'm in PAL-land so I will be shooting 1080p25 as my main format and 720p50/60 for slowmos.
Data rate and GOP/Intra will depends very much of what is the footage for.
Long boring interviews will keep going in 35Mbps.
The glitch in play is normal. Even if the NANO would be able to eliminate this, the next device (video IO card, monitor, TV) probably would introduce his own glitch.
I hope to get my NANO tomorrow.
I will have a lot of time to test it the next few weeks.
rafael

[Mohammad Farooqi]

Dear Dan,

Thanks for your informative reply. I am using a Sony EX-3 with the XDR, so when I am able to record slow motion on the Flash XDR via future firmware update, I will have problems because the EX-3 only does slow motion in 720P but I shoot mostly everything in 1080 24P. Now I know I can just dedicate CF cards for the two resolutions. I just think it would be nice to have the ability to record 1080i, 1080P or 720P on the same card for a run and gun type of situation. So, are there any plans to have a future release with the ability to do this, or is it just not possible?
Thanks

[Dan Keaton]

Dear Mr. Farooqi,

1. We can do this now.

Are you wanting to playback from the nanoFlash, or are you going to edit your footage in a NLE?

2. In a future firmware release:

If you are in 720p, then you will get over and under-cranking at 1 to 60 frames per second.

If you are in 1080p, then you can have over and under-cranking 1 to 30 frames per second.

If this meets your needs (unlikely), then you can stay with 1080p.

Note: 1080i will not be supported in our over and under-cranking feature.

[Billy Steinberg]

Originally Posted by Dan Keaton

If you are in 1080p, then you can have over and under-cranking 1 to 30 frames per second.

I presume this (1080p in any form, cranked or otherwise) will only be available when using the HDMI input, since (single link) HD-SDI doesn't support (have the bandwidth for) 1080p.

Billy

[Dan Keaton]

Dear Billy,

HD-SDI, single link at 1.485 Gbps, can handle 1080p23.796, 1080p24, 1080p25, 1080p29.97 and 1080p30, but not 1080p59.94 or 1080p60.

So in typical terms, we can use 1080p30 (usually 1080p29.97) for over and under-cranking.

However, this only offers the difference between 24 frames per second and 30 frames per second which may not be enough for the slow-motion effect desired. Thus, many choose to use 720p60 (usually 59.94).

1080p60 (or 1080p59.94) has too much data to be transmitted over standard 1.485 single link HD-SDI.