"Five" <Niko@fiveminutesof_blank.com> wrote in message

news:Qj9jc.41636$aQ6.2382411@attbi_s51...

> In article <sn7jc.40464$_L6.2360156@attbi_s53>,

> david.mccallUNDERLINE@comcast.net says...

> > "Martin Heffels" <zurssryf@arjfthl.pbz (ROT13)> wrote in message

> > news:gn4p801gcfmheehnb9eibigiih34dr6622@4ax.com...

 

> > It's a consumer/prosumer camera. There are pro HD cameras available now.

> > It's just that you don't get pro at that price point.

> >

> > I think it's a pretty cool development.  People are making "movies" with

> > DV (also a consumer format, technically). I think the low end indi market

> > will eat this thing up if they give it a low enough frame rate. Considering the

> > quality they have gotten out of DV, I think this thing may be fine. A low frame

> > rate gives a few more bits per frame, plus there is probably some temporal

> > compression (if that is the correct term in this context) and that gives you

> > some more bits to work with (while making editing a little more complex).

> > I imagine there will be issues with high motion scenes, but a low frame rates

> > inherently have issues with motion, so you should already be taking that into

> > account when planning your shots.

> >

> > David

 

> The biggest problem I see is that it is HDV.  That is

> taking a larger image, and compressing it more, and

> also doing so in a lossy format to the same size of

> capture media (DV tape).

 

Actually, the two compression types are quite different,

with different results. As I understand it, Mini-DV is

frame-by-frame MPEG1, with a data rate that provides

one hour of DV-SD  compressed 5:1 to fit on Mini-DV

tapes (SP-mode). MPEG2 is not frame-by-frame, so it

is easier to compress a higher-resolution image to less than

the Mini-DV SP-mode data rate with picture quality that

is in some ways superior in terms of visible compression

artifacting (though this compression type is harder to edit

easily). Also, as I understand it, HDV is either 1080i

(with all the motion-advantages of interlacing), or 730p

(with a PS frame rate of 30, too slow to avoid motion

flickering easily).

 

> We should at least get a larger tape even if that

> requires us to use large DV tapes.  IF size is of

> concern, then using a new formulated 8mm tape would

> offer longer potential run times due to the ability to

> put more tape in the shell.  You are creating a new

> format, so why not a new tape size and formulation.

 

The HDV standard, as I understand, was set with

the original Mini-DV specs - but there has been a

considerable delay in its implementation. I would be

all for a larger tape format, though, if it made recordings

higher-quality and/or more secure - or easier to edit...

 

> Speaking of which, panasonic pro has found the

> advantage of using metal particle over me tapes.

> The biggest of which is the problems of humidity,

> causing the tape/head contact transfer issues adding

> drop outs.  That is another topic.

 

From the old Hi-8 days, ME could hold more info,

but was less reliable for dropouts - and, as I understand

it ("AIUI"), Mini-DV tape is MP (the bandwidth is

sufficient for DV, and any extra would unlikely be

of much benefit, especially if ME is more "temporary"

than MP...).

 

> Anyone viewimg a wide screen image would have a TV

> that can display progressive, so why not get rid of

> the interlace?  720 p looks better on the proper

> screen, and with motion.  The size is easier to

> compress as well, so you loose less on the tape.

 

Actually, what you see now as 730p is likely 60fps,

not 30 - 30 in a big, sharp screen, viewed close up,

with sharp individual video frames (unlike film, which is

generally shot at relatively slow shutter speeds, introducing

motion blur) would likely be unpleasant to view with

motion. SDTV has been interlaced for a reason - even

with lower resolution, motion problems make 30fps

PS-mode undesirable...

 

> Yeah wide screen HD sounds great....on paper.

> I don't want it due to the problems after the cam.

> If you take a larger image, and compress it more going

> to the same size container, you will get something

> that is prone to all sorts of quality issues.

 

Not necessarily... Look at some top-end broadcast

HDTV on a really good display (not easy to find...).

Even with a data rate *lower* than Mini-DV (D-25),

it looks GREAT, with very rarely detectable

compression artifacting (unlike Mini-DV, with a

higher data rate).

 

> This is further complicated when you go to the editing

> stage.  You cut it up, add effects, and transitions,

> and then finalize it again to the same format (re-

> compress it) remember it is a lossy format of higher

> loss than standard DV.  This becomes your master, and

> then if you want to make DVD's, it gets compressed

> once again.  I can not see how this will be better

> than what I already have...just wider.

 

It can be better, MUCH better...;-)

 

> I think if they want to go wide, using the formats we

> have, a better option would be to go anamorphic.  That

> way, you have a wide image without adding file size. 

> This data can more easily go to 25meg formats.  YOu

> just need to make a special monitor that unstretches

> for your display.  Then you can edit and unstretch in

> you editing package to get your proper propotions

> digitally with out loss.  So why not make an

> anamorphic lens specifically for the camera, instead

> of an after thought.  That way you can eliminate the

> problems associated with zoom.

 

This is already being done. And some cameras

electronically compress the image horizontally, saving

all the pixels (though when stretched out to fill the wider

screen, the "unit area" resolution is lower than it is

with 4:3... (and I never liked the awkward 16:9 proportion

for image composition, anyway...;-).

 

> What would I like to see?

> I would like to see higher color signal processing

> Larger chip 1/2 or 2/3, and if you go natively wide,

> give it to me in 50meg format of your choosing, that

> is not compressed more than 5-1 or offer me a real

> time compressor to go to tape, that is non lossy, and

> can come from tape out an SDI port or firewire2 to

> restore the compression to its native form.

 

It's called D-50, with much lower than 5:1 compression...;-)

Still kinda 'spensive, though...

 

> In other words....CCD to compressor to tape, then from

> tape, through uncompressor our SDI.

> I dont want to give up quality for the sake of going

> wide.  I want my tape to be the same quality as the

> final cut master, not the master to be off lesser

> quality of my source tape.

 

Likely nearly as close to true for HDV as for Mini-DV...

 

> I want tape based format, for reliability, in the

> field, and longer running times. Build the camera for

> the shooter, not the editor.  Disk based systems, have

> too many potential buffer, laser, pickup problems and

> always will in the real world.

 

Not necessarily, but I prefer tape at this point, too...

--

 David Ruether

 d_ruether@hotmail.com

 http://www.David-Ruether-Photography.com