#Premiere/VVS Video Rates
9 messages in this thread
What type of capture rates are other users getting with Premiere 4.0 and the
Radius Video Vision Studio 2.0?
When you get ready to capture a new movie, under the Video Options dialog box,
you can set the data-rate for your captures. In the Compression section, hold
down the COMMAND key and click on the the quality slider. This brings up a new
dialog box where you can type in the data-rate to use. You can also have
Premiere rate your Hard Drive and tell you the fastest relible rate that you
can use.
That's the number I'm interested in hearing about. So far we've been capturing
at 1.7MB/sec. That seems slow to me and I want some feedback from other users.
BTW, our Hammer disk array checks out at a 7.1 rating using the tester that
ships with HDT.
System: PowerMac 8100, 40MB Ram, 250 internal HD, 4GB External Studio array
shipped with the Video Vision System.
Hi Craig,
I haven't used the Radius Video Vision Studiio 2.0 system you have so I
can't help you with your comparison numbers, but I thought I might say
that the 1.7MB/sec rate does sound kind of low to me too.
I am not familiar with HDT, when it says a 7.1 rating, is that saying that
your drive should be able to do 7.1MB/sec, or is that just a scalar
measurement?
-John
>>I thought I might say that the 1.7MB/sec rate does sound kind of low to me
too. I am not familiar with HDT, when it says a 7.1 rating, is that saying that
your drive should be able to do 7.1MB/sec, or is that just a scalar
measurement?<<
To be honest, I am not completely sure. I installed the VVS last week, and it
will be next Friday before I have a completely open day to start a full battery
of tests. I was specific in which programs were giving me the results I quoted
because I am not yet clear on what those numbers exactly mean.
From the brief displays I saw, it looked as if the HDT test was refering to
7.1MB/sec. That's what confused me about Premiere's low rating. I am producing
full-frame flicker-free video successfully. The digital compression being used
is creating a slight distortion around the edges of objects (it looks like an
average VHS-tape quality). This is fine for the offline editing we are
currently doing, but I'd like to see exactly how high a quality I can coax out
of this system. I do not believe that I could get any full-frame video at that
lower rate so maybe I am not reading things right.
Anyway, that's where I am. I'll be educating myself a lot over the next few
weeks, but I'd love any feedback from someone who's been down this road before.
-Craig Swanson
Swanson Tech Support
Craig,
Ok. Typical numbers that I have seen from professional non-linear
products range from 3MB/s to 8MB/s. It sounds like you are getting a
decent quality for that low a rate, however, I will be interested in
hearing your conclusions after Friday. Good Luck!
-John
>>Typical numbers that I have seen from professional non-linear
products range from 3MB/s to 8MB/s. It sounds like you are getting a
decent quality for that low a rate<<
That jives with what I have read and heard. The quality is not high enough for
fully digital work, but I was surprized at how good is considering the low
rate. Anyway, I will let you know what I find a week from tomorrow.
-Craig
I have been having the same problem with capture rates stating 1.6 megs/s for
my sledgehammer fast and wide 4.1 drive. The news I have heard is that full
motion, full frame video requires at least 4 megs/s, which should be possible
with the array. The strange thing I notice is that ALL my drives test at this
1.5 to1.7 m/s rate, drives with entirely different "real world" speeds. Before
I added the disk array, I was seeing number like 2.5 and 3.0 on the internal
and pockethammer. I am just hoping that Premiere has a calibration bug and is
really reporting flawed numbers.
We use a Sledge with Premiere 4.0 and VVS 2.0. I get around 3.7 to 4.0 MBs on
average for a 640×480 picture.
By the way, we experienced that if you digitize at 640 x480 with the VVS card
you will get a small black stripe down the right side of the image. It doesn't
show when you export because you overscan. Therefore, we reduced our image size
to 632 wide and you can't see the difference in the finished product. It was
some kind of glitch on one of the processing chips. It may allow you to reocrd
at a higher quality.
Ah, this question 🙂
QuickTime data rates (what you see in the Premiere quality settings) don't
reflect raw drive transfer rates (say, using FWB's utilities) much at all.
Those raw rates are for uncompressed data, which the hardware can compress as
it's transferring to yield really impressive numbers. The video stuff coming
out of your VVS card is major compressed, on the other hand. Hence the lower
numbers.
Which brings us to that rather confusing settings dialog. The higher the
transfer rate you set in there, the LESS the VVS (or whatever) card compresses
the video data (= better quality). The lower the rate you set in there, the
MORE the compression card squashes your data (= less quality, more lossy)
before passing it to the bus out to the array. It's a rather unintuitive way
to do such adjustments, IMHO.
Depending on what size video you're capturing (640×480, 320×240, etc.) and what
sampling rate you're doing audio at, you need to tweak this data rate setting
until you get what you want. If you're trying to get a lot of video into 4GB,
you may also need to compress your video more to get it all on.
– A.J.
>>QuickTime data rates (what you see in the Premiere quality settings) don't
reflect raw drive transfer rates (say, using FWB's utilities) much at all.<<
That is very true if you are looking at the sliding scale for QuickTime
compression that uses terms such as "most compression" and "best quality."
However, if you hold down the CONTROL key and click on that same slider, you
can set the rate (in Megabytes/sec) that video is captured to the disk. It is
true that the larger your image, the greate the compression will be needed to
achieve that rate.
BTW, an update on my earlier quest that started this thread. I just talked to
my client and they have succeeded is tuning up the system to capture at
5MB/sec. I am still going in to work on Friday, I will report back as to what
the original problem was. With that rate, they are happy with the quality that
we are seeing at full screen digital video.
-Craig