Uncompressed

[limo991]

>>>Give it 5 years and maybe all our modest PC's will be able to handle uncompressed and storage wont be an issue. Right now tho DVCPROHD is a good compromise for my setup.

A single disk can do a lot more than dvcprohd 1080p resolution uncompressed if it comes from a single CMOS sensor.

>>>I know this is going off topic, but I can understand how using pixel shift with andromeda gets a HD image from the DVX; but gaining more lattitude... i dont quite get it.

They just get the signal before it is reduced to 8bits. Depending on the curve you use on the DVX it could mean a lot more latitude.

>>>Not unless you were to say "well if it output DVCPHOHD rather than uncompressed you would lose those extra stops of lattitue'.

It does not have to. You can compress as much latitude as you want into an 8bit signal. I believe lin to log is involved anyway, so not much is lost in 8bit if properly done. DVX does not do the best it can in that department though.

>>>That I could understand, however Varicam also records to DVCPROHD and that codec isnt limited to recording a 7 stop lattitude. DVCPROHD even on varicam is 8 bit so I dont understand the argument that you lose lattitude because of the 8 bit system.

You can record the latitude you need at any reasonable bit depth but the relations between tones will change since you have to use nonlinearity. DVX is nonlinear in most modes so you have seen that.

>>>Is it just the simple case that the DSP in the andromeda is better than the one in the DVX? less information is thrown away?

I don't think so. They do not add much inside the box I believe. Just a tap and a usb controller probably. But it does not go through color sampling and dv compression so it is better.

[limo991]

Speaking of latitude, what do you think of this? It was shot in a completely dark room with only source the 100watt lamp running at full 240volts. This was shot with a digital industrial camera. I don't even want to estimate the latitude:)

http://img152.imageshack.us/img152/8082/latitude19ld.jpg (http://imageshack.us)

[limo991]

I didn't shoot it btw.

[Paul Coleman]

Yikes, beautiful.

[Shaw]

Limo, I'm not following your arguement. Maybe I'm just slow. :) I'm just trying to understand here...


I calculated the number of horizontal lines above. And the number of pixels the camera has horizontally. That does not change. It has nothing to do with vertical cropping since vertical stays the same.

You lost me here. To get 16:9 from this camera you merely crop the slightly wider than 4:3 image to 16:9. Simple, efficient, and you don't lose horizontal resolution unless you compress to a format like DVCproHD 720p. Resolution is resolution. As long as the chart is framed properly you can really use whatever chart you want. You could, for instance, shoot a 4:3 chart with a 16:9 camera and as long as you had the vertical alignment correct the horizontal would read just fine. The line spacing ratio doesn't change between 16:9 and 4:3 on the chart and that's what matters.

I'm aware that you will loose vertical resolution as you mention - that was part of my point. I just don't see how you would lose horizontal resolution.

[surf]

hmm, yes. hmm

[mmm]

http://img152.imageshack.us/img152/8082/latitude19ld.jpg (http://imageshack.us)

I wonder if the latitude is really that high. I mean most of the frame is very dark and the filament is bleached out. It is hard to tell because it is quite an abstract shot. I would prefer to see someone sitting in front of a window with no lights on them and bright sunshine outside.

[John Alton Disciple]

Hi all,

I was at NAB last year when Panasonic's head engineers (and their translator) came to the Reel Stream booth. They listened closely as Juan explained the Andromeda and how it works. After the translator finished recaping what Juan had said, I saw the most amazing thing. An engineer dope slapped his head, gasped something in Japanese and looked at Juan like he was a God. This time I didn't have to wait for the translator. Neither did anyone else. It was quite a moment. The translator smiled and uttered the words "Of course."

I've used the system and I appreciate the dedication Juan shows to the technology. He understands not only how things work, but also the physics and theory behind the gadgetry.

As a matter of fact, I plan on shooting my next film using several cameras, Juan's included. The extra latitude and color precision of the Andromeda will be put to good use. To me, that's where it's at. I'm even buiding a new edit system to take advantage of the benefits that the Andromeda gives me. The ability to over crank the HVX will be used on the scenes that are supposed to be slow-mo. And when we need to do it, I'll rent or borrow one. Storing all that data from tapeless systems is going to be a trick, but hey, that's how it is and I'm damn glad I'm not having to shoot on mini DV at NTSC resolutions.

Choose your colors fellas, it's a blank canvas world.

[limo991]

I wonder if the latitude is really that high. I mean most of the frame is very dark and the filament is bleached out. It is hard to tell because it is quite an abstract shot. I would prefer to see someone sitting in front of a window with no lights on them and bright sunshine outside.

Try to point your camera in a light bulb of this type in a dark room:) The dynamic range is over 100dbs. That's 50 times greater dynamic range than the best video cameras.

The frame is not dark. Everything that actually gets light is exposed. The only source is the filament.

[limo991]

Limo, I'm not following your arguement. Maybe I'm just slow. :) I'm just trying to understand here...



You lost me here. To get 16:9 from this camera you merely crop the slightly wider than 4:3 image to 16:9. Simple, efficient, and you don't lose horizontal resolution unless you compress to a format like DVCproHD 720p. Resolution is resolution. As long as the chart is framed properly you can really use whatever chart you want. You could, for instance, shoot a 4:3 chart with a 16:9 camera and as long as you had the vertical alignment correct the horizontal would read just fine. The line spacing ratio doesn't change between 16:9 and 4:3 on the chart and that's what matters.

I'm aware that you will loose vertical resolution as you mention - that was part of my point. I just don't see how you would lose horizontal resolution.

You don't loose horizontal resolution. I never said that. But the number of horizontal TV lines changes from 4:3 to 16:9 since the ratio changes. The chart fills the entire width of the frame in 4:3 but not in 16:9. Only compare charts of the same ratio or convert the lines to the appropriate ratio. Or compare actual pixels. In actual pixels and tests with proper ratio the Andromeda has a low horizontal resolution compared to the HD cameras.

Andromeda 800 horizontal ines is 800*4/3=1067 horizontal pixels.
Canon 700 (lets assume) lines is 700*16/9=1244 which is better than 1067 pixels.
Andromeda in 16:9 will be 1067*9/16=600lines.

So, forget 800lines. That's for 4:3 and is translated to 600lines in 16:9. For obvious reasons real-streem is not in a hurry to shoot a 16:9 chart since that will only be a little better than 600lines (since it goes beyond 800lines in the 4:3). Ignorance on how lines are to be measured and converted from 16:9 to 4:3 is used for marketing there. If you ignore whether the test is 16:9 or 4:3 you are only measuring a small part of the total horizontal pixels of the 16:9 cameras, the part that is covered by the 4:3 chart.

Lets take 2 cameras. One is HD 16:9 1024x576. The other is SD 4:3 768*576. Both show 576 horizontal and 576 vertical lines in tests. Are they the same resolution? NO! If you want to compare lines properly you have to convert to predict resolution of the 4:3 camera in 16:9 use. The 768x576 camera is only 768 pixels or 768*9/16=432 horizontal lines in 16:9 test. It is also only 576*3/4=432 vertical lines in 16:9 test (cropped).

[limo991]

Btw, 600 lines is the minimum since Andromeda goes beyond the 800lines limits and is pretty refined at the 800lines point. A 100000 lines camera would look like 800 lines in the chart also:) But that chart is the only think we have for now. We know it will show at least 600 16:9 lines and that's all we can assume from 800lines 4:3.

[limo991]

Pictures are better than words. Notice in how smaller area the chart has to fit in 16:9 shooting normal and anamorphic. 16:9 output from this camera will limit the horizontal resolution in lines no matter how you do it. If you shoot without anamorphic you also compromise vertical resolution. That results in less lines. That's why Andromeda appears far better than it really is. It is presented in 4:3.

http://img108.imageshack.us/img108/8583/1956modes9th.png (http://imageshack.us)