DVX DV compression (vs.) Uncompressed CCD Data

Matthew Bennett

Matthew Bennett

Well-known member
Here's a couple of shots illustrating what the DVX in-camera compression to DV looks like vs. a tap off of the CCD's (raw data before compression).

Here's the DVX: (the standard DVX image you get on tape)

Allison_DVX_compare.jpg


Here's the raw CCD data: (obtained by tapping the chips directly)

Allison_Andro_compare.jpg



Notice the yellowy plaque around the over-exposed areas on the stock image, and how gentle and film-like the roll-off is on the CCD data comparitvely. All this data resides inside the DVX, but gets processed and compressed out so the camera can put the DV stream on tape.
 
I've seen some really nice work with the andromeda, and have been thinking about getting the upgrade to my DVX for some upcomming greenscreen work.

Now I know this question is asked all the time but how do you find the workflow with the camera?
 
i think i'm going to have to tap out. :)

for the past hour i've been color correcting the first pic and though i was able to successfully remove the yellow (which came out nice i must say)...the glare i couldn't do anything with. though i got close adjusting "levels", but my "hard work" proved something that i hope helps you and me.

why fight for all that color correction when you can get it right the first time? :)

don't know if you've seen my "uncompressed capture" thread, but that's what i'm trying to explain. why go DV and then have to work and work to get the image you want when with the andromeda or in my case the video xpress you can get what you want right away.

note i'm not comparing the two because you're definitely getting more color space. i just know for a fact that i was watching our live feed and the playback from tape just wasn't the same and with the hundreds of posts (not just on this forum) that i've seen where people complain that their captured footage isn't the same as the camera...ya think :)

anyway i applaud what you are doing (granted i might not go that route) and you may be able to help me...how are you recording? i know it's USB, but are you using an external or the notebook drive? and for those who might be interested...

allison.jpg
 
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So that clip of the uncompressed green screen and all that.....that's not from the DVX right? It's an HD camera?
 
Matthew Bennet

Matthew Bennet

"Here's the raw CCD data: (obtained by tapping the chips directly)"

After you shoot with the DVX, how do you obtain the data from the chips, how do you get that data onto to your computer to start cutting it?

Once the raw data is edited and you burn to a DVD, will it retain that quality, or wll it look like the compressed DV footage?

Thanks... it looks amazing.
 
Hello,

The images are from a DVX100 with the Andromeda system installed (www.reel-stream.com). The Andromeda system basically allows you to record the raw uncompressed 4:4:4 RGB data directly from the sensors/AD converters inside the camera.

Because the DVX imagers employ pixel-shift much like the HVX and other cameras, it is possible to extract a higher resolution than what each sensor can natively support. The maximum supported output is 1540x984.

The DVX works internally at 12-bits/channel or 36-bit color per pixel. Andromeda allows you to apply RGB gamma curves(realtime LUTs) in this 12-bit RGB space, for recording to uncompressed 4:4:4 10-bit or 8-bit footage.

The system is composed of two components, the hardware which is installed on a DVX and the software which runs on a Mac. The hardware is not visible and sits inside the camera itself, the only difference is the additional USB 2.0 port that is added to the camera. The DVX itself works exactly as before, so you can do everything as usual. By connecting the USB port to a Mac running the included SculptorHD software, you can record uncompressed directly to hard disk.

One of the advantages of Andromeda that is evident in these images is the added dynamic range(latitude) in the high end. On the DV image the highlights on the face of the actress are clipped to a solid color, while on the uncompressed capture you can see further into the highlights. The added dynamic range has been measured to be 2.0 to 2.5 stops on the high end, when compared to the DV output.

Please let me know if you have any other questions!

Cheers,
Juan
www.reel-stream.com
 
Just had to say that the Andromeda footage in this thread looks 100% like film to me. It's SO beautiful, I like it a lot more than the SDX, F900, Varicam and stuff. It simply looks better and more filmic to me (except for the DOF, of course...).

I want Andromeda...
 
I was just about to post: "Reel_streem rocks, but no PAL", when I quickly went to their forum and read that as a few days ago, they are working on a PAL version....which seems somewhat imminent!!! WOA!!!!!!!!!!
 
Hello,

That's right, we should have PAL support soon. The PAL DVX should yield about 100-200 extra lines of vertical resolution when compared to the NTSC DVX. Andromeda not only extracts full bandwidth RGB (4:4:4) uncompressed 12-bit data directly from the sensors/AD's in the DVX, but also utilizes the pixel shift inherent in the sensor block to generate uncompressed frame sizes up to 1540x984(NTSC) or 1506x1168(PAL).

Andromeda output also exhibits increased dynamic range of 2-2.5 stops, particularly in the highlights when compared to the DV footage.

If you have any other questions please feel free to post them here or email me directly.

Cheers,
Juan@reel-stream.com
 
This looks amazing, but I would expect something a little cheaper, since I'm guessing most people would go with the HVX over the DVX + Andromeda for the same price.
 
wait a tick - so that means that the this andromeda system can't record on the field? ie you've gotta have a computer connected to the cam to record anything?
 
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