Cranking Issues. Help Needed.

[Fletcher Yeung]

Hi,

Just trying to test out over/under cranking via Flash XDR. Reading the instructions, I'm kinda confused. Just to be certain:
1. Over/under crank it needs to be I-frame at 720p25 at 35Mbit
2. When I try to set it to 35Mbit in I-frame mode, I get only 100/140/180/220/280
I don't think I can get 35Mbit in I-frame mode, correct? It only shows up as Long-GOP,
but I can't crank in Long-GOP correct?
I did try cranking with I-Frame at 720p25 at 100Mbit and an error of Card too Slow came up (which I was expecting)
I tried cranking with Long-GOP, it shows up as 720p25 at 35Mbit but only goes to Crank Frame Rate of 50. Which, then it won't go into FCP/Avid, as I already knew, but just had to test.
So, am I missing something here, how can I get I-frame down to 35Mbit to get cranking working? Oh, and the Flash XDR get's abit hot when cranking as well, is this normal?
Any suggestion would do!!!

Thanks!

[Dan Keaton]

Dear Fletcher,

In Item 1, you specify that you need 720p25 and 35 Mbps.

I understand that you want 720p25, but I do not understand the need for 35 Mbps.

With over and under-cranking, we do require I-Frame Only.

This limits you to the I-Frame Only bit rates: 100/140/180/220/280 Mbps.
(The actual bit rates available to you will depend on the speed of your card.)

So, yes, you can not get I-Frame Only at 35 Mbps.

What Brand/Type of CompactFlash card are you using that won't work at 100 Mbps?
Is this one of our qualified cards?

I do not know why the Flash XDR would get hot while over or under-cranking.

In the System Menu, we show the internal temperature. Please let us know what the temp is while over or under-cranking.

100 Mbps I-Frame and other I-Frame Only bit rates work in both Final Cut Pro and Avid.

[Fletcher Yeung]

Hi Dan,

Thanks for your reply. It was my understanding that Avid Media Composer can only handle Video Formats 720p24/25/30: supported at 35Mbit only at this time (am I reading this correctly). I did try importing 720p25 at 100Mbps into avid after cranking at Crank Frame rate of 50, (ignoring the slow card warning) and got an import error, I did manage to view a bit of it in VLC player, but it was choppy.

I'm currently using SanDisk Extreme 3, 32gb cards, which is qualified, but still getting the Card Too Slow Error, I'm running a test now in normal 1080p25 @ 100Mbps to test out if it is just a faulty card. So far it's been recording the past 30mins and the error hasn't come up.

As far as temperature is concerned, in just normal recording, I've seen it get up to 60degrees Celsius (the cards were hot as well). I'll check the temp again after I get done running all 4 cards through the test and let you know how hot it gets.

Thanks!
Fletch.

[Fletcher Yeung]

Hi Dan,

Just to check on the Temp, it's now at 53degrees celcius, and it's only been running for about half an hour. I've attached a pic below.

Fletch.

[Fletcher Yeung]

After an hour and ten mins of continious recording, the temp hit 60C. I didn't want it to get any hotter so I stopped recording, ejected the cards, and took a pic. This test was done in my office recording just the room (it's a/c controlled at 25C).

Fletch.

[Dan Keaton]

Dear Fletcher,

Is your Flash XDR gettting normal ventilation?

While 60 Degrees C seems slightly high, it is no cause for alarm. Is this running regular, or while over and under-cranking?

We have tested the Flash XDR at much higher internal termperatures, it works fine at 100 degrees C and fails about 105 degrees C (if I remember correctly).

Just so you know, it is not easy to get it to 100 degrees C. We have to run it for many hours inside an air-tight enclosure.

"It was my understanding that Avid Media Composer can only handle Video Formats 720p24/25/30: supported at 35Mbit only at this time (am I reading this correctly). "

I see where you got this information in our manual. I will check on this.

For now, could you run a over or under-cranking test with I-Frame Only, at 100 Mbps?

What over or undercranking settings are you using? I understand 720p25, but what is the crank rate, this should be 1 to 60?

What camera are you using?

[Piotr Wozniacki]

I also noticed that to the EX-line camera users at last, the most common overcranking scenario (720/25p at 60 fps, I-frame, at a bitrate that both the nano and the specific CF card allow) is of no practical use at the moment, since it is not supported by most NLEs (Vegas will not handle 720/25p at anything higher than 35 Mbps).

Since 720/25p overcranked to 60 fps, and recorded to SxS at 35 Mbps (well - actually much higher when overcranking - but this is the nominal bandwidth for playback) can be done using the EX1/3 camera, am I correct the overcranking in nanoFlash in its current state is only of practical advantage for users of other cameras which do not support overcrank themselves?

Dan, please confirm or correct me. Also, are you planning to work with SCS on higher I-frame speeds support?

[Fletcher Yeung]

Hi Dan,

Thanks for the reply again! The Flash XDR is getting normal ventilation, it's not enclosed or anything. Just out in the open on a table, hooked to my EX-1 for input, and to an HD-SDI monitor for preview. It's hitting 60C recording regular 1080p25 @ 140Mbps roughly at the hour mark of recording (it's actually hot at the touch as well, kinda reminds me of a Macbook pro running on your lap!)
As far as over/under-cranking, I did a short test and at I-frame, 720p25 @100Mbps at Frame rate of 1, it records just fine. But when I record at 720p25 @ 100Mbps at Frame Rate of 60, it starts recording, drops the Frame Rate to 50, then gives me an error message of "card 1 too slow" I"ve tried it on all 4 of my cards and same error message. I've even shot a small video and will host it up for you to see (I have your e-mail, so I'll send it to you shortly)
At the moment, I'm testing it out of my EX-1, and will test it on my PDW-700 as well. Any thoughts?

[Fletcher Yeung]

Hi again,

Yes, I just tested it on my PDW-700, and same results. Drops Cranking Frame rate to 50, when set to 60, then after 30secs, slow card error.....I can post up a vid of it if you'd like, but it would probably look the same as the first.

Fletch.

[Dan Keaton]

Dear Fletcher,

Thank you for the very detailed and helpful video.

I will be running a test shortly, and we will run formal tests in our lab.