XDCAM HD vs Nanoflash

[Mark Donnell]

Do any XDCAM HD (50Mb/s) users choose to use a Nanoflash or other unit to record HD-SDI rather than using the XDCAM HD codec ? Is there a visible difference between material recorded both ways, or is the Nanoflash or other unit mainly used to facilitate ingestion into a particular NLE ?

[Doug Jensen]

The NanoFlash records with the same 8-bit 4:2:2 XDCAM HD codec as the cameras, so you just have the option of a higher bit rate. Does a higher bit rate make any visual difference? I have never seen evidence of that no matter how much I have tested it on all kinds of subjects. The Nano makes a lot of sense for some non-XDCAM cameras, but is is hard to justify the extra hassle of powering the unit, mounting it, and disrupting the elegant XDCAM workflow just for a very small (if any) improvement in quality for XDCAM cameras.

If you want to go with a 10-bit Samurai, Ki Pro, or PIX240, then an external recorder might be worth it -- depending on your workflow.

[Alister Chapman]

When I had my PDW-700 I did use the NanoFlash to gain a more robust image for grading. At 100 Mb/s there are fewer compression artefacts. For some projects I also used the NanoFlash at 35 or 50Mb/s to allow the cards to be fed into the edit suit while I carried on shooting. A simple CF card reader (one is supplied with the NanoFlash) is a lot cheaper and more portable than a PDW-U1 or U2 disc drive. So with the 700 and a NanoFlash I had the option for either a disc based workflow, solid state workflow or combination of the two.

Other external recorders that use 10 bit recording can give a small advantage over the 8 bit XDCAM codec, especially if you are doing a lot of post production work. But that comes at the price of much larger file sizes. 50Mb/s XDCAM is very good and more than adequate for most productions. But if you really need to squeeze every last bit out of the camera a 10 bit external recorder will help you do that.

[Doug Jensen]

Originally Posted by Alister Chapman

When I had my PDW-700 I did use the NanoFlash to gain a more robust image for grading. At 100 Mb/s there are fewer compression artefacts. For some projects I also used the NanoFlash at 35 or 50Mb/s to allow the cards to be fed into the edit suit while I carried on shooting. A simple CF card reader (one is supplied with the NanoFlash) is a lot cheaper and more portable than a PDW-U1 or U2 disc drive. So with the 700 and a NanoFlash I had the option for either a disc based workflow, solid state workflow or combination of the two.

Other external recorders that use 10 bit recording can give a small advantage over the 8 bit XDCAM codec, especially if you are doing a lot of post production work. But that comes at the price of much larger file sizes. 50Mb/s XDCAM is very good and more than adequate for most productions. But if you really need to squeeze every last bit out of the camera a 10 bit external recorder will help you do that.

I challenge anyone who claims they can see the difference between 100Mbps XDCAM and 50Mbps come over to my office and prove it with a genuine double-blind test. It can't be done. I'll even let them designate the subject matter -- waving grass in the wind, blue skies, crashing ocean waves, high-speed sports, whatever they want. I'll even put in a moving wipe between the two shots. But if there isn't a border on the wipe, you will not even be able to see the wipe moving. Whatever difference there is simply can't be seen without a microscope.

As for dumping the elegant and sophisticated disc-based workflow -- just for the supposed convenience of using a CF reader instead of using a U1 or U2, well that is just ridiculous. Hey, how about using the camera for ingest, and then no extra reader at all is necessary? And who owns a F800/700 (and edits their own stuff) who doesn't already own a U1 or U2 anyway? And who cares if a CF reader is more portable than U1 or U2 -- because there's rarely ever a need to travel with a U1 or a U2. Not having to ingest and reformat cards every day is one of the best things about using optical discs. Shoot & archive all in one step. Nothing beats that simplicity. And how is powering and mounting a Nano on the camera all day during a shoot better than using a U1 or U2 for ingest?

Once, again some people are more bent on disagreeing and being argumentative than actually offering practical advice that makes sense.

[Alister Chapman]

Doug, why do you throw your toys out of the pram every time someone offers an opinion that differs from yours? This is a forum for discussion and debate. I try to add what I believe is useful input and alternative options, but you seem to take offence whenever I or anyone else offers a different view point. Forums are supposed to be places for open discussion, opinion and debate, if you can't accept that other people may have a different way of doing things to you, don't post here.

There are fewer artefacts at 100Mb/s than at 50Mb/s, that's fact. Take a look at the independent research papers that Convergent Design commissioned if you don't believe me. If there was no benefit to be gained from higher bit rates, then there wouldn't be an ever growing market for recorders that have lower compression ratios and higher bit rates.
Have you never seen the Panasonic demos where they break the XDCAM 422 codec by rapidly rotating the camera or shooting high contrast leaves fluttering in the wind? Yes it is very rare to see such artefacts in first generation material, as I said 50Mb/s is very good and it is adequate for most productions, but compression artefacts can make a big difference in post production. Images grade much better, especially subtle gradients like the sky or walls if there is less quantisation noise. I know your workflow doesn't involve any post work, but that's not the way I and many, many others work. Very often I am handing my footage off to production companies and I have no idea how they intend to handle the material.

Using an alternative workflow with CF cards is not ridiculous. There are many reason why someone might want to use the solid state workflow of the NanoFlash over the discs in the camera or to supplement the disc. If you'd read my post I give the example of when you don't have a U1 or U2, perhaps you need to continue to shoot (thus the camera is tied up) while material is ingested. You can hand off the CF cards to be off loaded while you continue to shoot with the camera simultaneously recording on to the disc if you want.

How about when working for a client where the client is going to take the media away with them at the end of the shoot but doesn't have an XDCAM deck. They can take the CF cards, ingest them at their leisure and then mail them back to me when they are done. Again I can shoot simultaneously to the disc in the camera and that way there are two copies for extra security.

How about shooting time-lapse with the camera while shooting real time with the NanoFlash? I used that technique to capture individual lighting bolts via the nano's cache record while doing a longer time-lapse of the storm internally.
What about when editing, doing backups or preparing media feeds on the run, in the back of a moving car. A CF card in a USB adapter is far more convenient than trying to use a camera or deck, especially if the road is bumpy.

These are not ridiculous workflows, these are just some of the many options that recording to an external recorder can sometimes bring. Just because you don't do it, it it doesn't make it ridiculous. There are many ways to make programmes, not just the Doug Jensen way.

[Doug Jensen]

The OP wasn't asking about hypothetical workflows such as you want to throw out there. That is a whole different conversation. He was asking about image differences, and I still contend that there is no visible difference. I have never seen it in any normal footage nor has anyone who has viewed my test footage. I invite anyone to send me the raw footage that proves that there's a difference, or is willing to come over to my office and allow me to prove my point. I will win -- and at the same time save them thousands of dollars in unnecessary expenditures and workflow hassles.

Seems to me that Panasonic and Convergent Design stand to benefit if they can show a difference, so that automatically calls into questions their results. Although I must say that I have nothing but the utmost respect for the people at CD -- but they have a horse in the race. I do not.

BTW, I rarely "rapidly rotate the camera" even if Panasonic thinks that I should be concerned about what happens if I do.

[Alister Chapman]

I apologise Mark, but I guess I had better not mention my opinions on the use of the NanoFlash with an XDCAM camera as they don't comply with the Doug Jenson one and only way to shoot.

Getting really fed up with this. That's another thread made worthless because there is only one way, the Doug Jensen way.

[Robin Probyn]

Originally Posted by Doug Jensen

The OP wasn't asking about hypothetical workflows such as you want to throw out there. That is a whole different conversation. He was asking about image differences, and I still contend that there is no visible difference. I have never seen it in any normal footage nor has anyone who has viewed my test footage. I invite anyone to send me the raw footage that proves that there's a difference, or is willing to come over to my office and allow me to prove my point. I will win -- and at the same time save them thousands of dollars in unnecessary expenditures and workflow hassles.

Seems to me that Panasonic and Convergent Design stand to benefit if they can show a difference, so that automatically calls into questions their results. Although I must say that I have nothing but the utmost respect for the people at CD -- but they have a horse in the race. I do not.

BTW, I rarely "rapidly rotate the camera" even if Panasonic thinks that I should be concerned about what happens if I do.

Hi Doug

The original OP does actually ask about ingest into NLE.. maybe the crux of the argument here is that for your market and your post equipment I'm sure you can't see a difference between 50-100 MBps.. but I think it just can't be denied that on more up market gear a difference can be seen.. but way up around 200 or so as CD themselves state its dimishing returns as the files become huge and the human eye cannot differentiate between the difference anyway.. Alister might be referring to the "top end" productions with maybe green screen and a lot of post grading..

[Mark Donnell]

Well, things have become a bit heated, but I do appreciate all of your comments with regard to this topic with which I have little personal experience. As I will not be doing multi-generation edits and copies, it would seem that the in-camera 50 Mbs codec should be fine for my purposes. Thanks again everyone.

[Uli Mors]

Well , i came just back from a one week camera training (HD422 + 35mm digital from 5D to F65) where I was the Broadcast (HD422 + 35mm up to F3) class trainer.

Here comes the challenge:

Blue Hour/Night shot:
an outside scene with 2kw Tungsten light, big HMI as "moon" light, a 2nd HMI softlight (dont know the wattages). All lights set up ~ 20-30m away from a scene with an actress.

Opposite to all other camera people we wanted to create a contrasty, colorfur "ready to broadcast" picture.

Thats why our class experimented with slightly crushed blacks as well (the other classes went into hypergamma or Log gammas instead).

Back in edit/postproduction compression artefacts caused by 8bit + low bitrate were very obvious and didnt hold up against better recordings: There was a slight moving pattern in every dark area (0-20% black).

Compression (especially mpg2) creates defined blocks. the borders of these blocks can be easily seen if you start levelling the blacks up again ("uh, thats to dark, lets change contrast/black here")

The higher the bitrate , the less these blocks show up. If recorded with 10bit, postproduction gets more food to play with, but thats another point.

YES, in our standard TV work, 50Mbit/s XDCAM HD422 is a perfect format. Its reliable and robust (I LOVE disks for that), easy to operate, cheap and for my work fast enough in ingest.

For cleaner pictures (less noise, less compression artefacts in black/grey areas) like industry videos, presentations, commercial, the NANO 100Mbit increases the quality by more than 2 (mpg2 artefacting is not linear to bitrate). Thats why we are thinking of using the PDW700 for higher quality productions (where we also use a F3) and combine it with an external recorder. If you set up the timecode right you can use the disk as your "Full HD proxy" and the Nano / Kipro Recording as the "Perfect Recording" and match timecodes in the Edit.

Also: Using the Nanoflash in 50Mbit HD422 mode, you can copy files per copy/paste to a professional disk - creating the same standard Disk AFTER the shot. thats how I hook up a HDCAM camera into my XD workflows.

my 2c

BTW: You two should definetely drink a beer together!

Best regards

ULi