Production Company - 720p Question

[Nathan Mitchiner]

Hello All-
I just received a NanoFlash rental unit in the mail today to use for high quality capture at a medical conference we are producing next week. Needless to say, I am very excited to be using this little wonder of a device. Unfortunately, we just found out the production switcher we are using to send the video feed to the NanoFlash via DVI w/ mini HDMI converter only sends 720p60 or 1080p24. Since we need smooth motion and not a film look, I am forced to capture only at 720p60 (MXF). Budget is set with the client and it is too costly to add gear that would enable us to send the NanoFlash 1080i60 instead.

So, here is my main issue - I have two Delkin 64GB cards at my disposal (total of 128gb) for the event and might have a timing problem of when to dump the cards depending on the data rate I use to capture.

Basically, the medical conference runs from 7am - 9am with a 30 min break and then 9:30-12pm with an 1hour long break. It then picks up at 1pm -3pm with a 30 min break and then 3:30-6pm and is then finished. So basically I have have 2 hour recording increments and 2.5 hour recording increments. I don't have the luxury of a Nexto device and will probably be using the included USB 2.0 reader to dump the data off of the cards either on the breaks or at lunch. I do have a firewire 800 reader and a pcmcia firewire 800 card for my PC (win xp) laptop but the pcmcia card is pretty suspect these days for some reason.

I will be cutting in Vegas 8.0c after the event and would love to use 100Mbps as a Data Rate since it is the "sweet spot" so to speak even though I will only be recording now in 720p60. However, according to the chart (Media | nanoFlash | Video Recorders and Converters) I just don't see how I can make that work based on my time schedule and the fact that it is going to take FOREVER to copy off 128gb of data on the USB 2.0 device if I have to try and dump both cards at the same time.

I guess I am open to suggestion by anyone of whether I really need to record at 100Mbps and how to try and time which cards to use (whether together at the same time or separately and dump one off while the other is recording)? Wish I could still record at 1080 but I will plan better for the appropriate gear production gear next year.

Also, since I am now recording at a lower resolution 720p vs 1080p, will I actually get more recording time per card and per data rate than what is shown in the chart on your CD website? I assume the chart is for 1080 recording instead of 720 recording or is data rate data rate any way you cut it?

Thanks for any advice from those who are a bit more experienced with tapeless CF capture than myself!

PS> For what it is worth, the medical conference feed will contain HD Satellite Feeds for Live Medical Cases, HD Camera Feeds, Presenter Laptop Content, etc so there probably won't be any fast motion or anything. I don't have to do 720p60. I can send another 720p flavor from the production switcher if anyone thinks that would be better for cutting in Vegas 8.0c?

PPS> And, if I am recording at 720p do I have to have the Progressive Recording Box Checked on the NF?

Thanks Again!
Nathan Mitchiner

[Andrew Stone]

Hi Nathan,

If you have the camera and the nanoFlash at your disposal this weekend, why not do test record. Fill up the cards and do a transfer to your laptop with both the USB and the FW device to see if you can do a transfer within the 30 minute breaks you have.

If it were me I would back down the bitrate so you have some wiggle room in terms of time and room on the cards should things bleed over. You don't want to go below 50Mbit as you will loose 422 color. Shooting 720p60 gives you lots of flexibility with conversion.

BTW, I was surprised at how fast the transfer was using the USB 2.0 card reader that came with the nanoFlash I got. I was expecting it to be much slower.

-Andrew

[Tim Polster]

Nathan,

I would not stress over the 1080 vs 720 situation. The most important fact is how are you delivering the final product?

In my work and testing, 1080i and 720p are visually pretty much the same viewing on a 1080p plasma television over blu-ray. 1080p (P not "i") has a bit more detail, but I would venture to say not enough to go crazy over in a home viewing environment. If you are going to a larger projection screen then 1080p would be the best option for all the resolution you can get.

Test, test, test. Find out this information for yourself with first hand knowledge and then you can make the judgement call. Shoot a little in every format and bitrate then put that footage on a Blu-ray or DVD and compare.

As far as your time constraints, use the 35mbps or 50mbps option to maximize your record time. Would your client rather have all of the footage at 35/50mbps or maybe some left out at 100mbps because of the limited card space? 50mbps looks very good and 35mbps will be fine as well.

I think 720p60 is a great and versitile format which I use the most out of all the choices.

[Mark Job]

Hi Nathan:
There are several ways you can go here. I do not use Sony Vegas, so I am not 100 % positive as to what are the file incompatibilities present with this editing application. I use Avid Media Composer as my primary post production application, along with FCP as my secondary backup. To conserve CF card storage space, I would consider the following possible settings......

1. Long GOP @ 50 Mbps data rate with .MXF file extension.
2. I-Frame @ 50 Mbps data rate with .MXF setting.
3. Long GOP @ 50 Mbps data rate with Quicktime .MOV setting (QT)
4. I-Frame @ 50 Mbps data rate with Quicktime .MOV (QT)

[Dave Sperling]

Hi Nathan,
Given your situation, I'd either bring in a couple more memory cards or go directly to 50Mbps MXF recording. As far as I know, a data rate is just that - the rate at which the data goes onto the card - and it's 'per second' so frame rate and resolution have no effect on the speed at which you're capturing data (unless doing slow motion?)
Anyhow, 50Mbps MXF LongGOP is still a very nice looking codec - it's the same one used by the Sony 700/800 XDcamHD 422 cameras.
But I'd still recommend getting one more card -- There are areas on the schedule that would stretch the 142 minute record time for a 64GB card - and the Nano does not take well to hot swapping cards, so if you're transferring your other card, you'd have to stop recording to switch once that transfer is done -- something you may not want to do during those extended periods. A third card - even if only a 32GB one - would buy you a little breathing room, and I think you really need it.
One thing about your transfers, it's always better if you can double transfer - to two hard drives or one external and one internal. Definitely bring fast drives for the transfers, and be organized -- set up the transfer station long before you need it. And do a test ahead of time to make sure that the card reader that was sent with the Nano has full speed support -- depending on the rental house they could easily throw a slow CF reader into the box, and you'd be up a creek waiting for the transfer to finish.

[Luben Izov]

Hello Nathan,
Long GOP 50Mbps is a very nice codec, you would like it, especially when you have only 2 CF cards at 64 Gb each for the whole day of shooting. Also, for your Sony Vegas I believe you need to shot MXF not QT (ProRes422 files is fine for viewing. They will be able to be read, but, Vegas just can't give you ProRes422 files back because Apple forbids it for PC). Someone with Vegas could confirm that. Anyone please!

Please do some test with the 720p as requirements and do some testing of the transfer of the cards. The card reader from CD is fine, but , it is the recording unit that determs the time of the transfer from CF card to the drive or a other CF Drive. On location with my travel SonyVaio I use this configuration for transfers - 500GB OWC Mercury On-The-Go Portable FW80... (MS8U7500GB16) at OWC
It has 400/800 firewire and USB all bus powered to 500Gb fast 7200RPM HDD. Cheap, fast and easy. Great pocket unit. Of course, format DOS (FAT32) for reading/writhing compatibility MAC and PC.
Good luck
Luben

P.S.
If you were somewhere near I could lend you some cards....

[Bruce Rawlings]

With tapeless workflow the pressure is enormous when you have to dump and delete original material against the clock. Surely the budget can stand a few more cards, as the expenditure is peanuts compared to the cost of something going wrong.

[Rafael Amador]

With the Nano you can record 720p30 out of the 720p60 from the switcher.
That at 50Mbps will gives you an outstanding picture and without the choppiness of the p24.
rafael

[Dan Keaton]

Dear Nathan,

You have, in my opinion, been given lots of good advice.

First, 720p60 can look very nice. 50 Mbps 4:2:2 is a great codec choice for this shoot.

As Dave stated, 50 Mbps gives you a certain amount of recording time, and it will be the same for 1080 or 720p.

With two 64 GB cards, you get approximately 5.3 hours of continuous recording time at 50 Mbps.

However, your hour-long lunch break is not adequate to upload 128 GB's of data, in my opinion.

You may get by, by uploading the two-hour segments in 30 minutes during the break, then re-formatting the cards. And you may get by, by uploading the 2.5 hour segment in the 60 minute break.

However, I would not risk it if I had another way. At the very least you should test the upload times before the event.

...The USB 2.0 Card Reader that we supply is the fastest USB card reader that we can find.
...Uploading to a computer depends on the speed of the card reader and the I/O throughput of the computer.

...A Firewire 800 CompactFlash card reader would be faster, but may or may not speed up the transfer, it depends on your computer.

…It is a shame that your PCMCIA is acting up, preventing you from using your Firewire 800 Card Reader.
...................PCMCIA = People Can't Memorize Computer Industry Acronyms (Grin)

...Record a test this weekend, at 50 Mbps, fill up the cards, then see how long it takes to upload with your computer. Or record two hours, then upload, then 2.5 hours, then upload.

...Please expect the sessions to go longer than scheduled, and your breaks to be shortened.

...I highly recommend that you make it easy on yourself and purchase or rent two more 64 GB CompactFlash cards. I recommend Delkin.

Note: For your event, you can also choose to use 35 Mbps (at 4:2:0). Your customers will probably not notice the difference. This gives you about 7 hours of recording time. Unless you have a great way of delivering the footage, it will probably be delivered at 4:2:0.

How are you going to deliver the content?

Personally, I am concerned about the signal source. Why is a video switcher sending out DVI?

Have you tested the nanoFlash with this switcher?

There are multiple potential pitfalls here:

1. The switcher is not a synchronous switcher, one that does not produce a glitch in the output.
If there is a glitch, the nanoFlash will stop recording until we can re-sync to the new video stream.

2. Why DVI? Is the switcher going to put out a real video signal, or a signal intended for a computer type monitor? The nanoFlash expects and demands a real video signal, not a computer monitor type signal.

This may be a moot point, as you have stated that the switcher puts out 720p60 or 1080p24. This is rather suspicious in itself. What brand/model switcher are you using?

Since you are going to use Vegas 8.0(c), you will need to use MXF, Long-GOP, not I-Frame Only. This is another moot point, since you will need to be recording at 50 Mbps or 35 Mbps, neither of which is available in I-Frame Only.

At the very least, you need to run a test, hopefully with the switcher included (and actually switching between sources). This test must include loading the footage into your editor and checking the footage.

How are you going to record the laptop presentations? If at all possible, get a copy of each laptop presentation and edit it in in Post.

For 720p, you do not need to set the Record PSF>Prog(ressive) option. 720p does not use PSF (Progressive Segmented Frames).

Please send me a private message. I will reply with all of my phone numbers. I will do my best to help.

[Piotr Wozniacki]

Originally Posted by Dan Keaton

Since you are going to use Vegas 8.0(c), you will need to use MXF, Long-GOP, not I-Frame Only. This is another moot point, since you will need to be recording at 50 Mbps or 35 Mbps, neither of which is available in I-Frame Only.

If I may suggest something on this point, you could download the (fully functional) 30-day trial of Vegas 9.0e, which handles I-Frame only files perfectly.

Hope this helps.

Piotr

[Mark Job]

Originally Posted by Piotr Wozniacki

If I may suggest something on this point, you could download the (fully functional) 30-day trial of Vegas 9.0e, which handles I-Frame only files perfectly.

Hope this helps.

Piotr

Hi Piotr: Yeah I thought Vegas *did in fact* handle I-Frame as well as Long GOP, but he said Vegas 8.x, so maybe that version doesn't do it. (??) Also, Dan, is it possible to add a 50 Mbps data rate setting for I-Frame recording ? I did not realize you cannot set the I-Frame data rate this low (Current lowest possible setting is 100 Mbps actually). I am assuming this is also true for the Nano Flash as well.

[Dan Keaton]

Dear Mark,

At lower bit rates, I-Frame Only is far less efficient than Long-GOP.

We do not feel that 50 Mbps I-Frame Only would acceptable quality.

The bit-rates/flavors are the same for the Flash XDR and nanoFlash.

At 140 Mbps and above, the actual image quality of the Long-GOP and I-Frame Only are about the same.

[Mark Job]

Hi Dan:
Oh ? OK. I haven't seen I-Frame @ 50 Mbps and assumed it looked as good as the Sony XDCAM HD 4:2:2 codec did at Long GOP 50 Mbps.

[Andrew Stone]

Originally Posted by Dan Keaton

How are you going to record the laptop presentations? If at all possible, get a copy of each laptop presentation and edit it in in Post.

Nathan, if you have to do the presentations "in camera" try to get a white balance of one of the projected presentations prior to the start. You generally have to dial in the white balance as opposed to finding a white spot. If you rely on the room white balance for the presentation portions of the event, your colors will most likely be way off when the projected presentations begin.

[David Issko]

Originally Posted by Dan Keaton

...I highly recommend that you make it easy on yourself and purchase or rent two more 64 GB CompactFlash cards.

My recommendation as well. You have to go into your job properly equipped. Even source 4 x 32Gb CF cards if you cannot get hold of 64Gb cards.

You can then spend the day concentrating on the job at hand - recording the conference at the data rate you want to.

Best wishes