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-   -   High Definition with Elphel model 333 camera (https://www.dvinfo.net/forum/apertus-open-source-cinema-project/63677-high-definition-elphel-model-333-camera.html)

Richard Andrewski April 12th, 2007 06:25 PM

I see how all this development will allow better control and storage of camera parameters in the camera, but how would it be possible to control camera parameters from a remote location, change them and restore them in the camera? I can think of some applications where it would be nice to control several cameras from one location and tweak them as necessary to get the best pictures. Cameramen may not always be involved (robotic movements for example) and there may be many cameras all supplying picture to somewhere else.

Oscar Spierenburg April 15th, 2007 10:01 AM

Andrey, will the new interface for the 353 also work for the 333?

Andrey Filippov April 16th, 2007 12:50 AM

Oscar,

Some features may be ported back, but I would not count on it - 353 has faster CPU and more memory. But we will help you to upgrade the camera to 353.

Odd Nydren April 17th, 2007 03:52 AM

Exposure...
 
Quote:

Originally Posted by Andrey Filippov (Post 657736)
Spectr noticed today what seems to be a bug in 3MPix sensor (not present in 1.3MPix and 5MPix) ones. No bug fix is available yet, we'll see what we can do (theoretically it is possible to synchronize new exposure setting with the start of the frame).

Would it be possible to create a function where you use a list of exposures during capture? (like in a text file or something)

Example:

I capture at 50fps. All the odd frames having a short exposure and even frames having a long exposure. Even though the odd and even frames will not totally match up, they can still be combined to create streaks of light after objects with high luminosity. (Blend the long exposure frames using "screen" blend onto the short exposure ones, at 30% or something - doesent have to match perfectly) Creatively this could be useful for several things.

There are probably other uses for such a feature that I haven't thought of...but would it be possible to do? (using PHP or something and not at firmware level - too complex for me)

Probably not possible without going deep into the firmware...but had to ask anyways ;)

//O.

EDIT: one obvious use would be HDRI capture...by capturing say 15 or 20 frames with short to long exposure...and then combine them in post.

Matteo Pozzi April 17th, 2007 10:01 AM

Have you see the picture from the NAB07 about the red camera!?
amazing ....I wonder how expansive is a sensor like the one of red one...
and the silicon imaging: I think that something really close to it could be made with the elphel.... they introduce a 35mm adapter so for me if they want to preserve the dof of a 35mm lens they have to use a gg adapter (optical solution preserve only field of view) but for that adaptor they wont about 4000$ ...maybe they have found a non gg solution? (fiber optical magnifier??)
so at the end we are working on something like them (optically side)


edit: the silicon imaging is a optical 35mm adapter like this: http://www.cine-one.com/pdf/angenieux_hdconverter.pdf

Zsolt Hegyi April 19th, 2007 12:28 AM

Quote:

Originally Posted by Matteo Pozzi (Post 661905)
but for that adaptor they wont about 4000$

Quality adaptors cost money:

http://www.pstechnik.de

With a bad adaptor (like the diy stuff people building here - none of them capable of HD resolution) no matter how good your camera is the picture will be ruined and you lose a lot of light too - you don't even need a lossless codec if the input is bad. My opinion is that DOF doesn't worth this.

Unfortunately it's really hard to find good industrial lenses (quality 16mm primes like Angenieux don't have HD resolution) which have the needed focal range/angle of view that can be used under normal circumstances. After a long search I decided to use Computar H2Z0414C-MP which has a zoom range covering most of a filmmaker's needs and its pixel count is sufficient for the new Micron sensor the 353 uses. You can find specs here, along with other lenses as well:

http://www.rmassa.com/manu/computar.htm


Zsolt

Odd Nydren April 19th, 2007 01:40 AM

Adapter...
 
I guess it all depends on what you are trying to achieve.

In my case, I am going to build a gg solution simply to be able to use my canon lenses...not necessarily to get DOF. (to get access to extreme macros etc)

When it comes to quality...to me - if it works for the end use - it works.
..things can always be better - but the important thing is...does it work??

There are people doing feature film on DV (!!) and acclaimed filmmakers too...so I think the real question that needs to be asked is really what we want to do and then take it from there :)

I will be very curious to see the results of your new lens! Please post a few shots when you have it??

thanks

//O.

Matteo Pozzi April 19th, 2007 01:47 AM

exactly the same lens I was looking at! (but to use in an dof adapter)
...for the adapter I'm not of the same idea.
a cinema picture need some spec to be recognized;
aspect ratio and dof are the more important I think
without that you'll have a very good and sharp picture that a viewer recognize like a news or something else but not cinema!
a cinema picture is a cinema picture also in a ipod video screen!
so if you want a cinema camera on the cheap you need an adaptor
and if you use good quality part you'll achieve a good compromise
...try to take a picture from daniel and scale down to 1280 and sharp it a bit...
(big sensor are too expansive now)

Zsolt Hegyi April 19th, 2007 02:24 AM

Quote:

Originally Posted by Matteo Pozzi
exactly the same lens I was looking at! (but to use in an dof adapter)

Zoom lenses have lower image quality. In an adapter you should use a fixed one I think.

Quote:

a cinema picture need some spec to be recognized;
aspect ratio and dof are the more important I think
without that you'll have a very good and sharp picture that a viewer recognize like a news or something else but not cinema!
Exactly. It all depends on what we call cinema. For me, cinema means theatrical projection of a film. If you have a higher budget then you can rent real HD cameras but if you have a lower budget then your film won't make it to the theaters, unregardless of the camera being used. I see the advantage of the Elphel when doing high quality TV or DVD films and this audience is not so concerned about DOF as some cinephiles are. Film grain effect can be applied in post if needed and gamma also can be varied if we're working with raw input. I'm into the Elphel because I don't have the money to buy/long-term-rent even a DVX100 - it's clear that a shallow DOF won't help my films to reach a wider audience because on this level other things count more. The Elphel has a huge price/performance potential but the performance alone won't beat the big guys like Red, not even SI.

Talking about resolution: most lenses give their best performance around f4.5. If you have an adaptor then you have two lenses with f4.5 plus the GG with f0.5 that's around f9 meaning you need a lot of light, not counting the fact that cmos sensors have a lower sensitivity than the usual daylight film stock has. If you open these lenses wide (f1.4 for example) to gain some light, you lose resolution again, plus you get some beautiful chromatic abberations as well. Remember the pictures made by the now-legendary Drake camera? They were working with super-fast lenses open as f0.9 and still got some underexposed images even though they've had a better sensor than the Microns.


Zsolt

Matteo Pozzi April 19th, 2007 08:00 AM

agree with you for the cheap of the camera (also to me the dvx 100 is expansive ) but I love the picture produced by a dof adapter ...look like a 16mm movie for softness ..thats my opinion
let's see how good will be the 5mp sensor in low light condition!

Andrey Filippov April 19th, 2007 09:22 PM

353 + 3MPix sensor
 
As roguebug suggested on our IRC channel (http://www3.elphel.com/irc -> http://irc.elphel.com/irclogs/elphel...04-13.log.html) we tried 3MPix sensor and it seems to work fine with 353. So now we have both 5 and 3 MPix (and I'm getting the first images from 11 MPix KAI-11002 - 10342/10347)

Matteo Pozzi April 20th, 2007 03:54 AM

cool news :-)
3mpx sensor I think it is better for low light!
any news about the rolling shutter issue comparing 3mpx to the 5mpx sensor?
on the camera that you gave me the link (pointed at a freeway) is evident infact tir or car are distorted about 60° left (higher distorsion for high speed)
to achieve a 2:1 aspect ratio did you think is better, to avoid the problem, roteate the camera 90°(left or right)?

Andrey Filippov April 20th, 2007 08:06 PM

Quote:

Originally Posted by Andrey Filippov (Post 663601)
...and I'm getting the first images from 11 MPix KAI-11002 - 10342/10347

Here it is: http://wiki.elphel.com/index.php?title=353

Andrey Filippov April 20th, 2007 08:08 PM

Quote:

Originally Posted by Matteo Pozzi (Post 663722)
cool news :-)
3mpx sensor I think it is better for low light!
any news about the rolling shutter issue comparing 3mpx to the 5mpx sensor?
on the camera that you gave me the link (pointed at a freeway) is evident infact tir or car are distorted about 60° left (higher distorsion for high speed)
to achieve a 2:1 aspect ratio did you think is better, to avoid the problem, roteate the camera 90°(left or right)?

Matteo, can you post a sample with distortion? You may upload it to our wiki (ignoring image size warning if any)

Matteo Pozzi April 23rd, 2007 08:48 AM

of course! but there is something like a tent that block the window view!


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