View Full Version : Hdrc


Biel Bestue
September 11th, 2006, 07:17 AM
what you people think avbout those cameras?

www.hdrc.com

Frank Hool
September 11th, 2006, 03:15 PM
correct me ....i may be on very wrong track but 170dB makes about 28 f-stops.

Forrest Schultz
September 12th, 2006, 11:33 AM
are these cameras being sold??

Frank Hool
September 12th, 2006, 02:10 PM
You can use such camera to shoot straight to sun and same time having human face in shaddow(it's easy to imagine, if You remember pictures Your granmothers last tourist trip - how white can be the sky and how black can be a face). Both will represented in full imaginable range. The only problem is there's no device which could represent it in full range. No need ND-s or any other filter.

Biel Bestue
September 13th, 2006, 07:15 PM
http://www.brightsidetech.com/

there is also a process called tone mapping you convert an HDR image to an 8 bit image preserving the correct luminance in all diferent regions with diferent luma values

here is some info about HDR:

http://www.debevec.org/

how are HDRC's cmos sensors compared to RED's or ORIGIN's Dynamic Range wise? anyone has any idea?

http://www.hdrc.com/isensors.htm

Wayne Morellini
September 13th, 2006, 11:45 PM
Good find Biel.

Yes, I have been eyeing some Kodak sensors (one above SD) with 25micron pixels for this sort of thing, but this is more convenient. I am interested, but if that is not the sun behind the person in the sample shot, I am not overly convinced.

smalcamerasensor (now owned by Cypress, as is Ibis5a sensor) claimed 120db (previous top I heard of). Ibis5a, is around 90db with multislope. Micron has dual slope WVGA sensor. Pixim has some sort of scheme, too, with a number of companies selling cameras using it. I expect to see more companies with this. What is good here, is the large sensor pads, hopefully this chip has good Signal to Noise ratio.

Frank Hool
September 14th, 2006, 12:01 AM
how are HDRC's cmos sensors compared to RED's or ORIGIN's Dynamic Range wise? anyone has any idea?
i think, 170dB is far beyound anything whats existing at moment in the world.

Biel Bestue
September 15th, 2006, 01:30 AM
question is, what resolution have those things, in the tech page it seems closer but not up to PAL

and the other question is what kind of data the chip gives

what exacly is 170 dB intraframe and interframe? i mean what Intraframe and interframe mean?

Frank Hool
September 19th, 2006, 01:51 AM
Red's official dynamic range would be 66dB(about 11 stops). http://red.com/techspecs.htm .
Which is fraction of given 170dB.

Biel Bestue
September 19th, 2006, 03:23 AM
the big problem of HDRC chips would be their low resolution no?

http://www.mpii.mpg.de/resources/hdrvideo/supplemental/hdr_video.mov

http://www.mpii.mpg.de/resources/hdr/hdrmpeg/HDRMPEG_hq.avi

http://www.cs.ubc.ca/~heidrich/Projects/HDRDisplay/HDR-Displays.mp4

tonemapping: http://en.wikipedia.org/wiki/Tone_mapping

Red's official dynamic range would be 66dB(about 11 stops). http://red.com/techspecs.htm .
Which is fraction of given 170dB.


what is Origin's?

Wayne Morellini
September 19th, 2006, 09:20 PM
I understand that the Origin is around the same, their site has some blurb about different ways of measuring latitude that lead some people to claim that a 11 stop camera is many stops higher, can't remember the details.

For now it is low res, we can hope they do a 720p big chip in the future, that might have less stops, but still be good.

Inter frame and intra-frame I don't quiet get, but intra frame is the only one we should be interested in. If they rely on sampling across many frames (accumulative or one frame slow shutter, next fast etc) then that is not so good, because you are relying on a comparison between frame intervals, and things move. For security cameras though, that would be great.

re-edit: The red spec says 66db or greater, so hopefully it has a good range.

Biel Bestue
September 20th, 2006, 02:31 AM
http://en.wikipedia.org/wiki/Video_compression

here it talks about inter frame and intra frame

it seems that intraframe is the most interesting, it's like uncompressed video

this is the 7th generation of the chip, i guess next generations (now that omron is producing them) will be more capable of higher resolution