4:4:4 12-bit Uncompressed DVX100

[Juan P. Pertierra]

I was playing around with the R,G,B alignment using the rez chart image. I seem to be getting an almost exact lignment if i resize the Red channel down by 1 pixel in both dimensions, and then align the layers.

Can anyone else try this with another RAW image and see if they get the same results? The blue channel is harder because it is slightly off focus, but this seems to get the green and red channels very close.

[Mike Metken]

If something like this could be done with the JVC HD 10, I'd buy it right away. You have a high def chip, high def lens, 16x9 aspect ratio. Juan, you may be the genious that could also be able to lock the exposure of that camera. Then you could use a 35 mm adapter and also do follow focus or whatever.

[Mike Metken]

Now, if you could do that with the upcoming 3 chip HDV Canon, you'd get rich fast.

[Juan P. Pertierra]

I considered which camera to start with at the very beginning, Canon XL1s, DVX100 or the JVC HD camera.

My first choice was the Canon due to it's popularity and the fact that you can put nicer lenses on it if needed, but due to some difficulties obtaining the manual i went with the close second choice, the DVX.

The HD10 was my last choice for a lot of reasons. First of all, the camera has other problems that need to be fixed, such as the exposure problem. That makes it more complicated, and I didn't feel like reverse engineering something just to make it lock exposure.

Second, the color off the DVX runs circles around the output of the HD10. I know that the buzz word right now is HD, and it's 'all' about resolution, but I personally think it is more about color and latitude than most people realize. When I mean 'more' i am talking about achieveing the film look we are all after, at least on TV. The HD10 uses a mosaic CCD which is halfway between doing an up-rez from a smaller chip, and actually have 3 sensors of the actual resolution. I say this because it is a hardware approximation of the full resolution. Although better than a DV uprez, I bet that a RAW 36-bit capture from the DVX up-rezzed has more dynamic range and color than anything the HD10 can do.

Look at 28 days later. The XL1se, even in PAL, has one of the smallest pixel counts of just about any 3CCD camera available today, yet it was able to produce some pretty cinematic images on TV. Now granted, there was a ton of sharpening on, but I think that was more about the look they were going for.

Now I haven't seen it on a theater, so it might be total pixelated crap on a projection screen.

I felt that with a raw uncompressed output in 36-bit RGB, full latitude of the chips and perhaps slightly larger resolution than standard NTSC you could come up with some great film-like images, and perform some great up-rezzing.

You be the judge, i have posted up-rezzed versions of RAW captures(look back in the posts) and compare them to the output from the HD10. I think you'll agree, it's leaps and bounds better.

The only question in whether I can do this with the new Canon(or any new HD cam) is if I can get the service manual for it, and of course have a camera to work with.

Juan

[Mike Metken]

Juan,

You're right. But since you started the project the market has changed a little and is moving in the HD direction quite fast. Also what you're doing would benefit the HD10 more.

You can get service manuals from Japan for free as a rule. I had the HD1 manual as soon as it was introduced. Give them some good reason in Japan and you'll get it for free. Some may be just there on their web sites. The one I had was in Japanese. The US version was not ready at that time yet.

You're doing a great job. Still look where the market is going in the long run.

I saw 28 days in a theater. The DV camera gave it that particular look, but believe me, if it was another movie, it would have been a total crap.

Mike

[Joel Corkin]

Mike, isn't the HD10 a 30p camera? The DVX though standard def, is 24P. 24P is what filmmakers want. This mod would be useful to filmmakers. Resolution is not the be all and end all of a filmic look.

[Mike Metken]

Joel,

About 200 screens at Landmark Theaters are going digital, in all major US market. There is some government grant or something to convert about 300 screens in Great Britain to digital, mainly to serve indie filmmakers. Even places as far as India are going digital. Sony is now introducing 4K cinema projector for $60K. The current theater projectors are 2K, optical or digital. The 2K projectors have about 2 MP (megapixels); the 4K projector has about 8 MP.

were always attempts to raise film speeds to 30 fps. Some 70 mm films were made in 30 fps with parallel cameras running and filming at 24 fps for dual 24 and 30 mm release. 30 fps failed because of the extra cost, nothing else. 24 fps being better is a myth. IMAX HD is 48 fps. The digital cinemas accept 30p digital prints. No optical print is needed. Currently there are about 100 digital screens in the US.

Mike

[Laurence Maher]

Ya,

I first saw 28 days later on a small tv set, and was blown away by how much it looked like film . . . but then I saw it on a large tv screen, and was blown away by just how much the look had changed. It didn't look like film at all to me then. I can only imagine what it would have looked like on a theater screen. I mean, the look worked for the film it was, but don't be too fooled if you haven't viewed it on at least a really big tv screen. What got that flick into national commercial theaters, was the fact that the director was already famous, and that it was a relatively good horror script, IMHO. Could never get away with that as a first time filmmaker with a drama.

I'm really stoked about your mod, Juan. If it works with great color separation, I think the camera you could turn the new Canon to come into just might be the end of the Hollywood grip on indie filmmakers.

And I LOVE you're considering Mac OS file system, becasue I personally am going to get a Mac soon (sick of unstabel pc) and need a great HD cam to go with it.

[Joel Corkin]

Hi Mike, Thanks for the info. I've seen and worked with 30P. I've seen and worked with 24P. I prefer 24P. The reasons are subjective no doubt and hard to describe, but that does not imply a myth. Is the fact that a drama at 60i looks like crap any indication that a higher frame rate does not necessarily mean better? It's not worth debating, but I'll give you my opinion anyway. Would higher frame rates be more "realistic"? Probably, but 24P (whatever the initial reasons for its adoption) seems to have hit a sweet spot in human visual perception that triggers us to a movie's "unreality" and its stylized difference from the crisp reality we know. Using an exaggerated example to illustrate, its like looking at a painting of someone instead of a photograph of them. It helps us to use our imagination a bit more, and it's a slight remove from reality that seems suited to fictive cinema.

[Jon David]

Hello Juan, everyone, another sideliner come out to speak here. Please bear with me here:

This is my suggestion. I'm just as excited as everyone else for Juan's Mod (especially after playing with the DV grab, and the Raw grab from the green screen test he posted a little while ago) but I'm afraid that this thread is getting a little...convoluted. I'm pleading with everybody, to please not let posts and conversations get any farther away matters at hand. What we need is to stay focused on getting a fully functional prototype system that allows one to capture 24fps 12-bit Raw files out of the DVX and write them out to a portable firewire 800 hard drive...that's IT. If people are interested in pushing other cameras (XL-1/it's sequel in limbo, that terrible JVC 'HD1U/HD10U' camera, or any others), please don't fill up any more pages of space on this particular thread asking Juan to start working on other cameras when he hasn't even finished the DVX-100 mod yet. Why can't we move some of this extraneous stuff to a sister thread of some sort, (ex: "Alternative Applications of Juan's 4:4:4 DVX Mod")?

Please, I'm begging everyone let's not forget, this thread is about the DVX-100 and it's already running 54 pages long. I think it's fabulous that such a dream come true of a project has been undertaken, found support and been so successful thus far. I'm just begging everyone not to get it bogged down here on other cameras and drives that Juan has explicitedly said he isn't planning on working on here (the dueling file formats, ext2/ext3/Fat32/ect, ect is tedious but necessary at this point in development I suppose) IE: if he says he doesn't want to work with that equipment or peripheral right now, let's respect that and not keep asking him.

Other than that, I'm excited to see things coming along and yes Juan you can chalk me up for your list when the happy day comes and this thing is complete.

[Juan P. Pertierra]

I need some help with this:
~~~~~~~~~~~~~~~~~
What exactly is a white balance adjustment? Initially i thought using the 'white level' in the 'levels' dialog in Photoshop, but that cuts off a ton of latitude, and that doesn't happen when I use the white level adjustment in the camera, so it's not the same procedure.

I'm trying to find the answer to this, but i'm sure somebody else here probably knows...

Also need help with..
~~~~~~~~~~~~
Verifying my R,G,B alignment procedure.
1.Open any psd R,G,B layered RAW from my site
2.Scale ONLY the red channel down by 1 pixel in both dimensions. Do this by using the Edit->Transform->Scale and resizing the RED(named "Background Copy") layer down by 1 pixel in both dimensions.
3.Select the move tool and use the keyboard cursors to 'nudge' the layers and attempt alignment.

Let me know if you can get a perfect alignment using this method. I've tried it on 2 images so far and it seems to work perfectly. I'd like to make sure.

Thanks!

[Helen Mets]

Hi Juan,

aligning the channels the way you suggested seems to work fine. I created a photoshop action for it:

http://www.hot.ee/whiteroom/alignment.atn

the red channel seems just a tiny bit high, but generally it's acceptable. I used the resolution chart you posted a while back.

As far as white balance goes, Auto color in photoshop seems to do the trick (should be used after levels correction)

[John Cabrera]

I was taught that the way to color balance an image was to look for areas that should be a neutral gray tone (you should be able to find one in any image... a wall, an eyeball, white fur, etc.) check each of the RGB values (it works best if you can sample a bunch of pixels rather than just one). If any of the three values is considerably more than the others, then that's the one you need to fix. If there's too much red, add more cyan... too much blue, add more yellow... too much green, add more magenta. When all three values are equal then the image should be correct. That's essentially what the camera does when you white balance... that's why you have to shoot a white piece of paper or white wall when you do it... or sometimes DPs will whitebalance through a blue gel if they want to get a yellowish tone or through an amber gel if they want a blueish look, etc. It gets tricky with images that are mostly rich color, but you eventually develop an eye for it. Anyway, there should be a color balance pallate in Photoshop somewhere. In the adjustments menu?

Also, I've been away from my computer for a few days but I did get a chance to play around with the image you posted a week ago. I've been meaning to post my results, but you got to it first... you're correct Juan. The Red channel seems to be getting scaled down by 1 pixel somewhere in the process of being squeezed down to the DV resolution. That's why the DV image is perfectly aligned. It's really strange... why do you think the camera needs to do that? Is it compensating for a natual error in the beam splitting or something... or the inner components? I understand the concept of comressing the 773 image to 730 to get a considerably sharper image (particularly that defocussed blue channel) but this oddly sized red channel has me stumped.

John

[Juan P. Pertierra]

That's great that you are all getting the same results.

My best guess is that this is to correct for the geometry of the prism. The re-size of 1 pixel is so small that any small difference in the optics could cause that.

The auto levels-auto color approach seems to work...here is an HD version of one of the last captures...this one was originally a VERY dark image and it is amazing how much detail you can pull out:

http://expert.cc.purdue.edu/~pertierr/cap10_HD.tif

This one was aligned with the new method.

I get the anamorphic adapter this wednesday, and I can't wait! :)

[Laurence Maher]

Juan, I sent you via email a grab of a color chart from www.pixelmonger.com in case you can use it for white balance alignment of the rgb colors.