viper ingeneer menus

[oao]

hi, i didn't approach the viper yet, i would like to know if it's the same process about the menus that it is with a 900 or varricam, do you set the black gamma, the master gamma, knee etc..the same way? What about the 1st op and 2nd op work?

[Landon D. Parks]

I was wondering sort of the same thing. Like if your still able to use the Video Processing tools in the camera (Gamma, White Balance and so on) and still output 4:4:4 2.39:1 native footage to an HDCAM or HDCAM SR deck?

 

Or in other woods, have the video fuctions of the F950, but the 2.39:1 Native aspect and 4:4:4 recording.

 

As too the little I know about the camera, You can either turn all video processing Off, and just record the RAW data from the CCD's or you can turn the Videp functions ON, And have video processing.

Edited January 22, 2005 by Landon D. Parks

[Guest Kai.w]

I was wondering sort of the same thing. Like if your still able to use the Video Processing tools in the camera (Gamma, White Balance and so on) and still output 4:4:4 2.39:1 native footage to an HDCAM or HDCAM SR deck?

<{POST_SNAPBACK}>

Taken from the Viper FAQ:

 

Why are there other modes in the Viper?

Although the best possible quality is obtained when using the FilmStream mode, there are

occasions when other ways of operating are needed.

Using the RGB mode still gives the full bandwidth of RGB 4:4:4 output on the Dual Link HDSDI,

but in this case the full range of camera processing is available within the Viper. This is

useful when you need to get the finished picture directly from the camera head rather than

waiting for the post production process.

HDStream mode is similar to FilmStream in that it uses no processing in the camera head,

but in this case the output is a component 4:2:2 signal. Where the highest quality is not

necessary, but the full latitude of the CCDs and flexibility of post-production processing is

required, this gives a signal that can easily be recorded on existing tape formats. You still

need to bear in mind though that these tape formats employ different levels of compression

and are not transparent.

Finally YCrCb mode gives the fully processed camera output in 4:2:2 form.

 

---

 

For my latest work we used the filmstream mode which does look rather ugly on the controlmonitor but grades very well in post.

 

 

-k

[oao]

what is the electronical control you have during the film sream mode? Even if it is raw signal 4.4.4 how does the camera react to high and low lights, what about the chroma? Whith the hd900 we control the picture with a 24''monitor and oscilovectorscope how do you control it on a viper if you get a sort of downconverted signal?

[Guest Kai.w]

what is the electronical control you have during the film sream mode? Even if it is raw signal 4.4.4 how does the camera react to high and low lights, what about the chroma? Whith the hd900 we control the picture with a 24''monitor and oscilovectorscope how do you control it on a viper if you get a sort of downconverted signal?

<{POST_SNAPBACK}>

 

http://www.thomsongrassvalley.com/products/cameras/viper/

 

Check the "documentation" section.

 

-k

[Landon D. Parks]

P,S) I also know you can have Hidden video fuctions on or something like that, where you can use video processing for your viewing monitors, but it still records the RAW un corrected data.

 

Very interesting.

[Claudio Miranda ASC]

I have only used the camera in 4:4:4 mode. In 4:4:4 mode you have no color controls. I would much rather do the color correction later. There is ways to view a look on your monitor, while preserving the raw data. You can set look up tables on the S2 for rough looks, but I hardly played around with that to much. For the look of the upcoming Heineken spot I shot for Fincher, I was able to pull off stills from the S2 hard drives and color correct them later to be used as references. Once the spot releases, I will show the reference on my site. You will be able to see the RAW file and the final side by side www.claudiomiranda.com.

 

The Viper deals well with highlights and low lights. For Xelibri, some of the practicals in shot light the people without blowing out or any other video artifact. On Heineken, we lit the street scence to very low levels. Letting the street lights blow. Shooting wide open for the most part. If you go too far in the toe end of the range, it does get a little noisy. You can get a better darker image if it is initially up, then crush it later. This helps eliminate the noise in the blacks.

[Derek Schweickart]

The idea behind the Viper camera is flexibility. You can certainly use it as a normal High Def camera in its 4:2:2 Y Cr Cb mode (like the F900), or its 4:4:4 RBG mode (like the (F950). When in those modes it has full video control. The added advantage is being able to forfeit this control and record raw data in 4:4:4 10 bit log color space. Shooting 10 bit log essentially gives you and extra 2 stops in your highlights (two real stops, not like cranking up your knee) and I think it's about a stop and a half in your blacks. Like Claudio says, it's always better to give your blacks a little more light then crush them down later.

In fact, when shooting raw the Viper will not produce a pure black, they tend to sit around 12% on a full range waveform monitor. This is because the black we are used to is a function of the gamma applied to the image.

 

"what is the electronical control you have during the film sream mode? Even if it is raw signal 4.4.4 how does the camera react to high and low lights, what about the chroma? Whith the hd900 we control the picture with a 24''monitor and oscilovectorscope how do you control it on a viper if you get a sort of downconverted signal?"

 

In filmstream you can modify the viewing channel which is a Y Cr Cb signal. Otherwise you can simply point, focus and expose for 320 ASA (400 in daylight).

It is a good idea to monitor the signal with a 4:4:4 waveform such as the Omnitek, but you can pretty much rely on 320 ASA to be accurate.

 

What I have found is that when properly exposing an image on the Viper for 320 ASA the waveform functions somewhat differently because you are dealing with a logarithmic signal which is not balanced. Also the green channel is always higher than the red and blue because there is no internal correction, and green light is always more prominent.

 

What is interesting is that 18% grey falls at 25% on the scope. A white card falls at 50%. Above 50% you have 2-3 stops before you start to clip.

Even though the raw image seems underexposed, when you balance out the colors and add gamma in post, the image looks correct and you end up with much greater latitude than if you shot in a non-logarithmic mode.

 

Filmstream is not a WYSIWYG system, but once you understand what it is doing it is a very simple system to use. The best is to pull frames off of the S-two recorder and tweak them in Photoshop, or Final Touch HD.

 

At the Camera House we are working on building an extensive set of Look up tables so you can get a good sense of what your scene can look like when shooting in Filmstream mode. These would be applicable on the fly and only affects the signal to the monitor. While I'm at it, any feedback on this subject would be much appreciated.

 

Derek Schweickart

Digital Tech

The Camera House

7351 Fulton ave.

North Hollywood, CA 91605-4114

818 997 3802

[Elhanan Matos]

Hey Derek,

 

Did you guys get the Venom in yet? If so how does it work, do you need multiple Venoms on each shoot so that you can keep recording while the other unit is dumping the shot to the S.two?

[Derek Schweickart]

Hey Derek,

 

Did you guys get the Venom in yet?  If so how does it work, do you need multiple Venoms on each shoot so that you can keep recording while the other unit is dumping the shot to the S.two?

<{POST_SNAPBACK}>

 

 

Elhanan,

No Venom yet. Thomson will unveil the Venom at NAB and they should start selling them by summer. So they say. We plan on getting the Venom as soon as we can.

You are absolutely right as far as the workflow goes. There would need to be two Venom per camera, one for recording and one for transfer. I think two is all that is necessary but that depends on how the Venom data is transferred. Dumping to the S-Two will be real time because you'll basically playback from the Venom onto the DFR. I don't know if there's a data transfer option on the Venom, but that could be longer than real time, and in the case of long steadicam shots, it may be necessary to have more than two Venoms.

I hope people will use the Venom only when cabling is absolutely not an option because I am sure that the DFR affords you many more options.

[oao]

Thanks a lot for your answers.