High Definition with Elphel model 333 camera

[Jose A. Garcia]

Ok, so with the Elphel is it possible to program a long exposure time to get more motion blur while keeping a short frame readout?

[Matteo Pozzi]

yes, you can
take in mind that the motion blur you can achieve is somethig different to the one you 're looking for
cmos sensor function like a paper scanner
take a look at
http://wiki.elphel.com/index.php?tit...FAQ#Background
maybe it clarify you some more about the elphel camera

[Oscar Spierenburg]

Originally Posted by John Robertson

what framerate did you shoot this in? because I was reading that it was hard to capture complex shots without frame drops and all that stuff and they were talking 19fps

I always shoot at 24Fps. The frame drops are mostly caused by the amount of compression. I can shoot perfectly at 85% 24fps with the Elphel 333.
And if I understand correctly, in the future it should be possible to record the stream of the 353 directly to a separate hard drive, leaving more power on the laptop, so you can crack up the compression quality even more. (Andrey correct me if I'm wrong)

It reminds me of old film cameras but IMO it lacks some more motion blur, that's why I'm asking for the shutter speed you used. If it was 1/48 then it means the Elphel cannot deliver a really cinematic mblur.

I prefer to reduce the rolling shutter artifact above motion blur. Maybe it's a stupid suggestion, but you can add pretty realistic motion blur in software like after effects, maybe even in VirtualDub.

1) Oscar, your short project looked great. Is there a reason this setup isn't ready to be used on other short films?
2) (everyone) It sounds like the "bugs" or "roadblocks" remaining have more to do with software issues than hardware. Is this correct? And if so... is it a matter of colaborative manpower?
3) Could someone with a production (but not engineering or technical) background (like me) purchase some of the equipment and collaborate somehow without knowledge of the programming end of it?

1)My current setup is fairly usable for short films. I don't have a short film planned right now. I just want to work on some things a bit. I'll post my plans for a dual lens adapter soon. And I'll be working with the 353 model.

2)Yes, and this forum is a wonderful place to get all ideas together. ...it's more a question of collaborative 'brain' power.

3)We tried to make the control interface of the 333 model more suitable for film making, but I hope the software for the 353 model will be easier to modify.

[Wayne Morellini]

Originally Posted by Daniel Lipats

They were all shot at 85% quality and I was using a letus35 on all of them except 1.png which I believe to be the most sharp in the bunch. Im not comfortable using 90% yet because of the risk I may get a dropped frame.

It seems that when I use the 35mm adapter the video is not as sharp. I need to do some more tests, it may be that im not properly focused on the gg or possibly just because the lens is wider open.

Thanks Daniel.

35mm adaptors are notorious for not working well with HD cameras. I don't know what peoples are up to in the adaptor threads, but there were HD ones.

[Jose A. Garcia]

Just a question... Can the new 353 capture 4:2:2? What about raw bayer for later filtering?

Thanks.

[Andrey Filippov]

Originally Posted by Jose A. Garcia

Just a question... Can the new 353 capture 4:2:2?

No, just 4:2:0

Originally Posted by Jose A. Garcia

What about raw bayer for later filtering?
Thanks.

Right now the raw Bayer code is broken, but I'll restore it in couple weeks (needed for a very urgent project). It is a special type of JPEG (where pixels are treated as monochrome, but rearranged in each 16x16 macroblock) that I described somewhere in this thread (should better put it in our wiki)

[Jose A. Garcia]

Hi Andrey,

I just found the posts talking about that bayer jpeg but I still have some questions.

Does "bayer jpeg" mean we can have full color info stored into a bayer pattern for later filtering but with jpeg file sizes?

Can you still get HD resolutions at 24fps with that kind of compression?

Thanks!

[Andrey Filippov]

Originally Posted by Jose A. Garcia

Hi Andrey,

I just found the posts talking about that bayer jpeg but I still have some questions.

Does "bayer jpeg" mean we can have full color info stored into a bayer pattern for later filtering but with jpeg file sizes?

Can you still get HD resolutions at 24fps with that kind of compression?

Thanks!

As full, as in the sensor itself. But, of course, 8bits/pixel (as in JPEG). That is also not a big loss as we use non-linear ("gamma") table on the input that makes the data to match noise performance of the sensor (see http://www.elphel.com/actualbits.html).

Current code in the camera (ported from 333) runs compressor at 120MHz, pixel rate is 1/2 of that and with 4:2:0 it corresponds to 40MPix/sec sensor pixels).

In the 353 the components are faster, so it can run (and is tested) at 160 MHz (53MPix/sec with 4:2:0). Our special "raw bayer" JPEG might run faster (80 MPix/sec @ 160 MHz), but the current FPGA code still waits for non-existent color components, so the compression speed is the same.

[Jose A. Garcia]

Great, thanks Andrey.

[Wayne Morellini]

Thanks Andrey.

Some people are interested in 2 mpixel shooting, I think that 1/1.3mpixel shooting might be more practical in terms of quality. As there is no Bayer below full resolution, is there any chance to use the binned color components, as I described before, to form an 1mpixel Bayer pattern?

At what average compression ratios does the Bayer codec achieve lossless, and visually lossless, Andrey.

I thought that 4:2:2 and 4:4:4 was automatically available with higher quality? Was ti always 4:2:0.


Thanks

Wayne.

[Matteo Pozzi]

hi to all yesterday I've taken a compact flash extreme 3 2gb card for cheap
....it is a 20mb/s read and write card amazing maybe it will be enough so we haven't any power issue and no need of a hd!
one idea I've in mind looking at oscar short film and other hd 24p shoots!
cause to the design of the ccd or the cmos sensor comparing digital to film shoots you can notice an evident flickering in the digital one due to the minor motion blur so, to fix this , in high light shooting why don't shoot in 48p mode and overlap frame one with 50% trasparent frame 2 and so on to achieve a smooth 24p footage...did you think it is possible diectly in camera or it is best to make it in post!?

[Matteo Pozzi]

oh and I've seen on the net that there are 8gb and more
extreme 4 card (85 euro) and are 40MB/sec read and write!

[Wayne Morellini]

Originally Posted by Matteo Pozzi

hi to all yesterday I've taken a compact flash extreme 3 2gb card for cheap
....it is a 20mb/s read and write card amazing maybe it will be enough so we haven't any power issue and no need of a hd!
one idea I've in mind looking at oscar short film and other hd 24p shoots!
cause to the design of the ccd or the cmos sensor comparing digital to film shoots you can notice an evident flickering in the digital one due to the minor motion blur so, to fix this , in high light shooting why don't shoot in 48p mode and overlap frame one with 50% trasparent frame 2 and so on to achieve a smooth 24p footage...did you think it is possible diectly in camera or it is best to make it in post!?

Another future idea would be too shoot 50p full shutter for TV and digital cinema, slow video and audio by 4%, and drop every second frame to get 180 degree 24p?

[Jose A. Garcia]

Why not shoot at 1/48 sec exposure time while keeping frame readout time low? Andrey said it's possible.

[Matteo Pozzi]

Originally Posted by Jose A. Garcia

Why not shoot at 1/48 sec exposure time while keeping frame readout time low? Andrey said it's possible.

yes you can but I want to increase the motion blur! with your method you'll get very sharp image that result in a flickering video like "28 days later" movies