HMC150 questions answered...

For those concerned about "backing up" the AVCHD media in the field for fear of losing your work, someone mentioned earlier that the SafePhoto II might be an option. Well, we did it and it works. While we didn't do AVCHD tranfer from an SD card we did do HDV from a Compact Flash and did ~5 gigs in about 15mins. While the transfer rate is a little slooooow in our opinion it is a nice companion. In the field we see mounting the unit on our side with a belt pack, dropping the production card in the unit and start the transfer, then let it click away the gigabits while we are shooting on another card then change cards as often as needed.

Now for those thinking otherwise, we WON'T format and reuse the card in the field because of our past experiences on messing up data through operator errors and also SD card failures, but instead we will KEEP the inexpensive card and take it to the studio for editing along with the back up hard drive data. The idea here is (assuming we go HMC150) we will use the SD card for production and transfer to editing - while retaining the HDD data offloaded onto DVD data discs or other HDD's for archival or back up purposes (as the case may be) until the project is completed or filed in the case of archival customer or internal requirements.

Now here is even more sweetness, the unit is simple to use and battery powered PLUS it comes with two charging options for the Li-ion battery, USB cord and AC. Slick. Don't know how long the battery lasts but the 160 gb's means we can store up to about 10 of our Compact Flash cards (if full of course) which is a real plus!
 
For those concerned about "backing up" the AVCHD media in the field for fear of losing your work, someone mentioned earlier that the SafePhoto II might be an option. Well, we did it and it works. While we didn't do AVCHD tranfer from an SD card we did do HDV from a Compact Flash and did ~5 gigs in about 15mins.
Click to expand...
Thanks for the report, it is great to know that we have a cheap option for backing up the footage.(Those who lost data due to corrupted media will know how important it is)
Now all I need to know if it is gonna work for the AVCHD transfer (SDHC card) as well.
 
I was re-reading the specification sheet when I noticed something that slipped by me before:

HMC-150_CABAC.png


An entropy coding design including:
  • Context-adaptive binary arithmetic coding (CABAC), an algorithm to losslessly compress syntax elements in the video stream knowing the probabilities of syntax elements in a given context. CABAC compresses data more efficiently than CAVLC but requires considerably more processing to decode.
  • Context-adaptive variable-length coding (CAVLC), which is a lower-complexity alternative to CABAC for the coding of quantized transform coefficient values. Although lower complexity than CABAC, CAVLC is more elaborate and more efficient than the methods typically used to code coefficients in other prior designs.
Click to expand...
In simple English, the higher level is CABAC, which is better quality and more processor intensive than the lower level, CAVLC.


While this will take more processing power, I'm still happy that Panasonic chose the higher lever (Higher Quality) over the lower level (easier to process).


Bob Diaz
 
VGurcu said:
it is great to know that we have a cheap option for backing up the footage. Now all I need to know if it is gonna work for the AVCHD transfer (SDHC card) as well.
Click to expand...

How about something like this:
http://nextodi.com/en/product/eXtreme_en.html

The enclosure itself is $129 at MyDigitalDiscount.com (authorized reseller for Nexto.) Then you put your own SATA hard disk in it.

Photo Safe II looks less expensive; I can't tell if it does data verification. The Nexto does data verification and claims to be 3x faster (Photo Safe II says it copies 5mB/sec, Nexto claims 15mB/sec from SDHC, up to 25mB/sec from CF). Photo Safe also only has USB connectivity, the Nexto provides USB and also eSata. Battery life looks to be different too, the Photo Safe claims its battery will last for 16GB, the Nexto claims its battery will last for 80GB.
 
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Barry_Green said:
How about something like this:
http://nextodi.com/en/product/eXtreme_en.html

The enclosure itself should be about $165. Then you put your own SATA hard disk in it.
Click to expand...

Wow, I'm impressed. And I just got a new 500Gb sata disk for my Macbook Pro... :Drogar-Love(DBG):

Although tempting to use the 500 in this unit I think Im best just dropping in the old 160Gb for field backups. Way cool!

The other unit mentioned here didn't sound at all speedy

THIS SOUNDS FAST!!


Thanks Barry
 
BobDiaz said:
In simple English, the higher level is CABAC, which is better quality and more processor intensive than the lower level, CAVLC.


While this will take more processing power, I'm still happy that Panasonic chose the higher lever (Higher Quality) over the lower level (easier to process).


Bob Diaz
Click to expand...

Great stuff Bob. I am hoping to keep on "discovering" how great this camera is long after the newness wears off. Should have mine next week, finally heard some ship dates.
 
shrigg said:
1 hour of DVCProHD is 24.76 Gb in 720p60 or 48.88 gb in 1080i60/p30
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Ummmm.... sorry, but that's incorrect.

1 hour of 720p60 or 1080 (any frame rate) DVCProHD is about 52 GB (in terms of what the camera records)

In Native mode, 720pN30 takes about 26GB/hr; 720pN24 takes around 21GB/hour

1080 is always 52GB/hour from the camera. 60i or 30p in 1080 will always be 52GB/hour; if you remove pulldown from 1080p24 footage in your NLE/ingest process, it can be stored at a slightly more efficient 42GB/hour.
 
BobDiaz said:
While this will take more processing power, I'm still happy that Panasonic chose the higher lever (Higher Quality) over the lower level (easier to process).
Click to expand...

Hey Bob -

I'm not so sure this is the case... reading the source of your second quote, it looks to me like AVCHD uses CAVAC, CAVLC, and VLC for different elements of the encoding. Not sure that Panny's really made much of a choice, or if anyone else does it differently...
 
VGurcu said:
Thanks for the report, it is great to know that we have a cheap option for backing up the footage.(Those who lost data due to corrupted media will know how important it is) Now all I need to know if it is gonna work for the AVCHD transfer (SDHC card) as well.
Click to expand...

Actually according to the SafePhoto II manual (if I am both reading and understanding it correctly) it doesn't care what's on the disc. It just copies files, folders, etc. as a sort of duplication of what's on one's disc. We've also found that we can have other material on the disc when we use it for video and all it does is create a "video" folder which is super. Yesterday I ran out the door, grabbed an x133 CF and just shoved it in the machine not realizing it had all of Barry's clips on it (was using the disc as a sort of transfer device to our editing machine from the laptop) and when I got in yesterday there was Barry's files AND the video folder. Hmmmmm, should have copied all that over when we did the test this morning. If I still have Barry's files on that disc I'll try it oot.
 
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Barry_Green said:
. . . Battery life looks to be different too, the Photo Safe claims its battery will last for 16GB, the Nexto claims its battery will last for 80GB.
Click to expand...

Yes Barry, the SafePhoto II battery does not last long at all. Ours died quickly during the third transfer of about 5gb of CF data and we were wondering if it is defective. If this is the devices battery lifespan, one would have to have AC available to be totally effective which would negate it from being a real sound field back up device. We're charging it overnight and going to try it again tomorrow and if it's the same it's headed back to NYC :o(
 
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ullanta said:
Ummmm.... sorry, but that's incorrect.

1 hour of 720p60 or 1080 (any frame rate) DVCProHD is about 52 GB (in terms of what the camera records)

In Native mode, 720pN30 takes about 26GB/hr; 720pN24 takes around 21GB/hour

1080 is always 52GB/hour from the camera. 60i or 30p in 1080 will always be 52GB/hour; if you remove pulldown from 1080p24 footage in your NLE/ingest process, it can be stored at a slightly more efficient 42GB/hour.
Click to expand...

I should mention I was only entering the times into the Digital Heaven widget to arrive at those figures, if you have real-world file sizes those would obviously be more accurate!
 
ullanta said:
Hey Bob -

I'm not so sure this is the case... reading the source of your second quote, it looks to me like AVCHD uses CAVAC, CAVLC, and VLC for different elements of the encoding. Not sure that Panny's really made much of a choice, or if anyone else does it differently...
Click to expand...

I couldn't find the location where you said AVCHD uses "CAVAC, CAVLC, and VLC for different elements of the encoding.", could you please post the quote and the link.


Thanks,

Bob Diaz
 
Hey Bob! There is no such location. I was intuiting. But let me look for what gave me the idea... ah yes, the third part, right after CAVAC and CAVLC at http://en.wikipedia.org/wiki/H.264 :

A common simple and highly structured variable length coding (VLC) technique for many of the syntax elements not coded by CABAC or CAVLC, referred to as Exponential-Golomb coding (or Exp-Golomb).
Click to expand...

It reads as if it might mean: CABAC for some things, CAVALC for transform coefficient values, and VLC for other things. Or not!
 
Well, I'm doing a buying lidt for accesories and I was thinking about a tripod, which would the ideal camera under 1000$ for this camera (with an on camera light)?
 
ilauzirika said:
Well, I'm doing a buying lidt for accesories and I was thinking about a tripod, which would the ideal camera under 1000$ for this camera (with an on camera light)?
Click to expand...

I was spoiled early on by an O'Connor 50 and ever since then the typical Bogens have seemed very poor to me in use. There's nothing like the smoothness of a high quality fluid head but there is usually a high price tag along with that smoothness.

Maybe the Seccid Sachtler clones in this thread would be in your price range, certainly worth considering.
 
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