Record uncompressed 14-bit (4:4:4) on your HVX200

arrestthisman said:
You need Ndiswrapper just to even hope to get wlan working, and Ndiswrapper is for linux and needs to be recompiled for OSX. There are a lot of hurdles and unless you know some basic programming it can be difficult. Not impossible, but difficult. PM me if you need any help. :)
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Not sure how you could help me if you couldn't get yours up and running... but thanks...

FRAME RAMPING: What exactly are you guys talkin about? I'm assuming under/over cranking but I'm probably wrong?

For Color Grading and Correction I've actually been playing in After Effects. But not sure if that's a similar process to what Juan described, with image sequences and such.
 
Kholi, free ramping is when you can change the speed of your capture while filming.

Ie, capturing at 24P "ramping" up to 60P, and ramping back to 24P in one take.
 
Oh nice. I actually just realized that after I posted. But what's the advantage of doing that in camera as opposed to recording in 24pN/60p and taking care of it in post? Where you aren't stuck with what you've captured?

Just wondering.
 
TimurCivan said:
because then the motion is perfect, no "blended" frames.
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Got it. What about light? How does ramping like that in camera effect the image as far as lightint is concerned. Going from 24p to 60p in camera affects light being let in, would this be the same for the image?

Or would that not matter since it would be a program independent deal?
 
the image darkens, but because its smooth it looks ok.alot of times if you pay attention in ramped Slomo scenes, you will see Flourescant flicker, and a grainer grittier look. it does have side effects. look at Issac Brody's "Teddy bear" film in the HVX grabs section. i shot a segment of hif film where we alternate from Slomo to Regualr and the footage is darker.
 
Since Juan is tapping directly into the DSP chip, which is always running @ 60p, I wonder if that will change or perhaps eliminate the ramping artifiacts you guys are talking about.

I could be dead wrong, but if that is the case then essentially you could just change the thrown out frames + playback speed. If the source is always constant that should affect the image characteristics. yes? No?

Kholi: You obviously didn't read my post. I did get it up and running, I just had no internet because Ndiswrapper compatible drivers were not available for my laptop at that time. Ethernet worked fine though, so if I didn't care about wireless... but I did, so...
 
TimurCivan said:
the image darkens, but because its smooth it looks ok.alot of times if you pay attention in ramped Slomo scenes, you will see Flourescant flicker, and a grainer grittier look. it does have side effects. look at Issac Brody's "Teddy bear" film in the HVX grabs section. i shot a segment of hif film where we alternate from Slomo to Regualr and the footage is darker.
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Can you point out an examples in mainstream films? I'm trying to think of one to check it out.
 
Kholi, I think most high budget films will adjust the iris as they ramp; so they'll have a bunch of light and have the iris more closed when running at normal speed, and as they start ramping up they'll adjust the exposure at the same time (opening it if frame rate increases).
 
Kholi said:
Can you point out an examples in mainstream films? I'm trying to think of one to check it out.
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The druggie girl with the machine gun in "Lock stock and two smoking barrels" While not a true ramping shot, you can see how the image degrades slightly beacuse of the 250+ FPS speed.
 
TimurCivan said:
The druggie girl with the machine gun in "Lock stock and two smoking barrels" While not a true ramping shot, you can see how the image degrades slightly beacuse of the 250+ FPS speed.
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That shot was freaking sick.
 
arrestthisman said:
Since Juan is tapping directly into the DSP chip, which is always running @ 60p,
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It doesn't. It runs at anywhere from 2 to 60 fps. He's tapping into the CCDs, and they scan at variable rates, not just at a fixed 60p.
 
With the Varicam, we used the Clarity Image - Varispeed

When we rented it with the Varicam a few years ago, it was mostly a new product, the rental house and DP did not fully know how to get the best out of it at that time. When we ramped the exposure would over/under expose during the ramp. Subsequently learned it is possible to ramp and keep exposure in balance, though not rented this combo since, so can not comment. Need to tweak a menu setting in the Varicam, from memory.

A Hydra/SculptorHD 2.0 ramp would be way cool. I think you need to somehow also ramp the HVX exposure control. Juan, having a GUI with an interpolated spline based ramping interface for fps/time and exposure, wow...:D
 
I did a little more research. With the Varicam, you change certain settings within the camera menu, so that you maintain a constant exposure during the ramp.

I am not sure if the same result would occur with the HVX set to a specific exposure, say 1/48, as opposed to syncroscan setting of 180 degrees shooting 24p. Exposure of 1/48 at 4fps and 1/48 at 60fps is going to be vastly different during a ramp? Perhaps there is some magic going on with the Varicam? Shame I never followed up on the Varicam/Varispeed test I did to understand how it properly works.
 
I didn't know that Barry, thanks for clearing that up.

Is it the varicam that always scans @ 60P? Or am I confused and thinking about RECORDing in 60P at all times?
 
Hello,

The CCD's scan at variable frame rates depending on the in-camera settings. So when you select 24P, the sensors are truly scaning 24 complete progressive frames a second. I think the source of confusion comes from the DVCPROHD format, which afaik always records 60 frames. If the camera is set to a lower frame rate then I think frames are duplicated. This allows for frame rate flexibility in the format but at frame rates lower than 60 my understanding is that there is wasted bandwidth.

Cheers,
Juan
 
pertierr said:
About frame ramping, it can probably be done but it would almost definitely be an 'active' mod since we would be insterting signals into the camera board.
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Juan, early days for Hydra and you have a lot of other work to do. I understand that pressing the record button on a DVX/Andromeda triggers SculptorHD to start recording. Is this ramping/exposure control concept practical to code and do you have means of making SculptorHD transmit instructions in the other direction, to the HVX?
 
Christopher,

No, the camera record-button control is a new feature for Hydra. Andromeda is normally controlled separately from SculptorHD, and the camera itself operates independently from Sculptor/Andromeda.

About the ramping function, Andromeda and Hydra are passive add-ons, which means they don't insert or change any signals on the camera itself. Essentially, the camera doesn't know it's even there.

A function such as the addition of frame ramping would require an 'active' add-on which would bypass/insert signals into the camera board. We're always attempted to stay away from this, but if there is high demand for it, we could make it an option of some sort.

Cheers,
Juan@reel-stream.com
 
Thanks Juan, I now understand, even though you had to say it twice.

OT: Still puzzled how the Varicam with the Varispeed controller can maintain a steady exposure during a ramp. Perhaps the Varispeed can be used with the HPX-500 as a Varicam alternative. Not sure on the development cost and interest of an HVX 'active' add-on. HVX/Hydra, first things first. :thumbsup:
 
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