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Bruce Morgan
12-12-2005, 04:09 PM
Having seen the latest specs on certain new cameras in dv realm and seeing the file size to get 40 minutes of dv footage on 200 gigs with a"professional" Panasonic 800 dv camera which uses the p2 card (see american cinematographer 2005 december issue ) vs the very latest hvx200 and the fact it collects high def dv with a ratio of 90 minutes for 100 gigs via p2 or firewire .
I am aware of huge compression issues that are at work on the new system cameras that are considered "hot" i e hvx 200 .
So when a camera like hvx 200 is compared to the vari cam what is the loss of picture quality due to what must be massive compression ???? .
In the brochure for the hvx 200 I see a statements about 1080p 60 aquistion and a warning "keep in mind " the recording method is a matter of choices
but
immediate changes thereafter are due to compression or so I assume .
In this case if you look at a pansonic 800 camera using p2 cards and the hvx 200 I repeat the compression has to MASSIVE .
This is not a complaint about the emerging technology .
However
if a test could be run on image structure resulting at the deliverable end ie dvd or screen projection or film out and dont forget standard tv and standard big screen ntsc type sets .
If If this is tested and shown
we who own and work with dvx100a and (in my case a host of 35mm film cameras ) We will know when to buy intoi the upgraded technology
Again this is not a complaint .
This is a querry .
The HVx 200 has great promise .
But compression is a factor existing right behind the prsim of most cameras .
1) Where can I read more about this compression issue and view tests and test charts with comparisons to the vari cam output .
2) Where can I see tests of the hvx200 out put to film , tv , digital projection and tv via dvd player .
In other words proof of this cameras aquistion and output preformance through display on a standard deliverable ?
3) in post most authoring systems include another compression factor before burningh the final dvd or wahtever .
Adobe , Sorensen , Canopus and many others .
How do they match up ?What does each of these compression systems do to change the image after so much hard work at lighting and all the other labour in aquistion ?
I saw the comparison with dvfilm and vegas and magic bullet but I am asking to see how these progarams and the authoring programs respond to this present camera and its inhernt compression factors .
I post this in Technical under the dvx100 forum for a reason .
It is at this point where we still have a dvx100 and may move up that we need to consider all these factors .
Meanwhile I have a dvx100a and thanks to the great thread on uprezzing i have a chance to offer myself and cclients some version of Hi def dv in post .
Thanks for any respose or comments .
I am trying to learn here .I dont want to start any wars over the new camera .
Thanks
Bruce

esperman
12-12-2005, 04:13 PM
DVCPRO-HD compression is the same whether it's originated form varicam or hvx200.

Bruce Morgan
12-12-2005, 04:35 PM
DVCPRO-HD compression is the same whether it's originated form varicam or hvx200.
In that case I must do more research into the capacity of the p2 cards used on the American Cinematographer shot dec 2005 .
I still see that the hvx200 is getting 90 minutes record time at 1080p using a 100 gig out board drive
where as the Pansonic 800
is only getting 40 minutes record time at 200 gigs .
I assumed this was due to compression used in the hvx200
Ill have to check the chosen file they were using in the 800 .
Thanks
Bruce

hopalongmedia
12-12-2005, 05:40 PM
I believe that DVCPRO HD 1080 at 30p should be around a gig a minute.

Check the brochure for the HVX on Pannasonic's website. They have a comprehensive table there.

The format/codecs should be the same. What you get with the ENG P2 cameras is bigger chips (2/3") which have greater lattitude. Also all the nifty big lenses and stuff you get with the big cameras.

Bruce Morgan
12-12-2005, 09:23 PM
oh
so it is just a case of gross visual information
coming on the superhighway of a (2/3") chip
instead on the mini road 1/3 chip .
Well Ill be a digital Hayseed
Shucks and Thanks
Cheers
Bruce