4:4:4 12-bit Uncompressed DVX100

[Kin Kwan]

Juan, I love you. j/k j/k :P

But you are a good man for doing this all by yourself and all in your free time. *Pat on the back*

Can't wait to see the site!!!!

[Phil Rhodes]

Hi,

Yes, there are lots of ways to taint the result, particularly if you start confusing yourself with unnecessary stuff like Mr. Adams' system. The system designed with very controllable printing in mind, for use with still photography, so its relevance to even motion picture film work is at best limited - and I fail to see that it has anything to do with determining the absolute dynamic range of an imaging device.

Phil

actually the zone system is a three-fold process: controlling exposure, controlling negative density in processing (for b/w negs), and printing (which actually requires the least amount of precaution of the three steps). and like i said, it's totally possible that even someone inexperienced with a light meter could properly perform the tests, but it's simply my advice to get an experienced professional photographer who's fluent with the zone system. though the zone system wouldn't be used at all during the test, i feel it's safe to say that a fluent practitioner of the zone system will generally have a broader understanding of the way light ratios and spot meters work. basically, it's a safe indicator of in-depth knowledge.

if you were setting up a post facility and needed to setup a router, you could probably have an intern do it-- it's pretty simple and is more or less plugging cables into slots and making a record of it. but if it's something that you want to do once and never worry about it again, wouldn't you prefer to have an engineer with years of experience to do it?

also, based on years of reading ac, it seems like a large percentage, if not most, of "hollywood" dps use the zone system. its advantages in shooting motion picture (in terms of controlling exposure) are more so than still photography, in my opinion. especially when you have subjects moving in and out / to and from light sources, and have blocking changes that are being decided by someone other than the photographer/dp, in addition to the fact that it just plain gives you more control over how your images will look. i'm not trying to sound like a snob -- unfortunately, snobbery seems to often be associated with the zone system, which doesn't make sense because it's pretty easy to learn.

and with shooting video, it's completely irrelevant. all you need is a good monitor.

[Phil Rhodes]

Hi,

> i feel it's safe to say that a fluent practitioner of the zone
> system will generally have a broader understanding of the way
> light ratios and spot meters work

That's exactly my point, it's got nothing whatever to do with ratios - we're looking at absolute range.

Then:

> basically, it's a safe indicator of in-depth knowledge.

But then:

> it's pretty easy to learn.

Um, er?

My problem with this is that it isn't a safe indicator of anything. It can be learned out of a book in about half an hour. And anyway:

> and with shooting video, it's completely irrelevant. all you need > is a good monitor.

Whaaaat? We're talking about video here! And anyway of course it's relevant! Differently-implemented, but still relevant. The system isn't tied to any way of metering light, it's a way of thinking about pleasing compositions in tonal value as well as space, which is relevant to anything that records an image.

Phil

> The system isn't tied to any way of metering light, it's a way of thinking
> about pleasing compositions in tonal value as well as space, which is
> relevant to anything that records an image."

sorry dude, but you must have the zone system confused with something else (like maybe EVERYTHING ansel adams ever wrote), because it's about the science of light's mechanical effect on emulsion, and fundamentally not about aesthetics.

and again, the zone system is indeed irrelevant for video (at least today's video) because the response curve and latitude are different from film emulsion. in fact, the zone system was developed as a way to have a mental equivalent of what video users have nowadays... a way to see the exact dynamic tonal range of the image we're acquiring (a full-res monitor).

and though the zone system is easy to learn, it requires more effort than thirty minutes of reading. and based on your inaccurate analysis and interpretation of the zone system, that's apparently how you learned it.

but again, i'd suggest juan get a pro who knows the zone system to help him out. at the very least, he'll save on not having to buy a spot meter.

for the sake of everyone else on this thread, i'll formally withdraw from this argument. sorry to juan and everyone else for wasting space.

[Joel Corkin]

Jaan, I appreciate your comments because I know what you are talking about. You aren't wasting space.

I think your suggestion of getting the help of a photographer/cinematographer who knows how to use a light meter could help Juan measure the range between the first visible details in a dark part of the image and the last visible details in the whitest part of the image.

A simpler way, not requiring a light meter, would be to shoot a white towel under constant, soft lighting. Stop down until you can just barely descern details in the shadows using a well calibrated monitor. Note the f-stop. Then open up until you can just barely descern details in the highlights. Note the f-stop. The difference is your usable lattitude.

[Chris Rubin]

Juan,

if you like, I could give you a hand by professionally grading some sample images for your website. As we all know, the main idea of 12-bit uncompressed footage is less about the appearance of the original capture and more about the expanded grading/scaling/sharpening possibilities in post. Side by side comparisons of dv footage and 4-4-4 footage (both graded for objectivity) could really make an impression on your potential customers.

Cheers,
Chris

[Chris Rubin]

Alright guys, here's an example of latitude for ya.


http://www.hot.ee/chrisrubin/leaves_comp_sd.psd

This is a frame Juan posted here several months ago, before he had figured out the exposure / white balance bit. It is in Photoshop format, with two layers - the original (as posted by juan) and the graded one. This image represents possibilites far beyond the scope of dv. Notice also the noise, which, although clearly visible, looks much more like film grain than digital distortion. It's pleasant to look at. I've seen lots of weakly lit 16mm material blown up to 35mm and projected on a large screen - this sample here is very similar to that.

La vita è bella,
Chris

[Aaron Shaw]

Chris,

I can't seem to open your file in Photoshop 7. I keep coming up with an error that reads:

"could not open: .... an unexpected end-of-file was encountered"

Was this image created with Photoshop CS?

[Chris Rubin]

Yes, it's done with Photoshop CS. But I was able to open it in PS 7.0 as well, albeit as a flat image. I think you may have an incomplete download. Try downloading again...

Chris

PS:

here are the same layers as jpg's:

www.hot.ee/chrisrubin/leaves_before.jpg

www.hot.ee/chrisrubin/leaves_after.jpg

[Aaron Shaw]

Thanks Chris :)

[Gary McClurg]

So any ideas how much this mod is going to cost. Plus what about repairs since I'm sure there will be a few bugs until everything is worked out.

[Eric MacIver]

Wow... I've never had the pleasure of working with a 16-bit "DV" image before. Amazing out of that "darkened" base image what you can get with a little adjustment of the levels and gamma curve. I took the darker (original CCD) image and applied to very easy tweaks to it and it came out great.

If anyone wants to see, I put it up at:
http://www.madmojo.com/leaves-edit.jpg

I am curious to see what the dynamic range of this ends up being. Seems to me that it would end up being similar or the same to what the camera normally offers, because I would guess that the camera just has a set curve/gamma adjustment it makes on the image before it gets compressed and saved to the tape. If that was the case, it would seem like if you used a similar setting, that you could expose properly for the tape and the firewire out, which would be very nice for "backup" and post processing reasons.

Of course, I may be way off base here.

[Joel Corkin]

"Seems to me that it would end up being similar or the same to what the camera normally offers, because I would guess that the camera just has a set curve/gamma adjustment it makes on the image before it gets compressed and saved to the tape. If that was the case, it would seem like if you used a similar setting, that you could expose properly for the tape and the firewire out..."

Eric,

This is what I figure as well. It makes sense. There might be a little gain in dynamic range, but what's important is to test and determine how much gain there is if any.

That's why I suggest the dynamic range test as I posted in my previous post. Others might have suggestions too that could be better.

[Eric MacIver]

Yes, that's a great idea. I'd love to get my hands on the same image taken with DV and with the mod, in the same lighting conditions, etc. to see what kind of gamma/level adjustments could be made to make them look as close as possible in terms of hue, luminance, etc.