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Topics - Scipione205

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Hello,

I was thinking about collect as much infos as we could regarding the use of Octave for generating test patterns and process RAW files (also combining dual iso images in one single 16 bit linear or stuff like that).

I didn't used Octave for years since I had to studying Linear Algebra, so I'ma sking for help.

Regarding Blender, the node compositor wich supports Python scripts and OSL is very interesting for this kind of stuff; I already opened a discussion on blenderartists about that.

Any help regarding Octave? (getting started, examples, tutorials, etc.)

Regards.

**EDIT June, 28th 2015**

I had a little chat with Alex, and he he gave me those two links:

http://www.marcelojoeng.blogspot.com/2012/11/compile-octave-using-1632-bits-colour.html

https://jethomson.wordpress.com/2010/08/22/enable-octave-to-read-16-bit-images/


for understand how to compile Octave for 16bpc processing.

The following link:

http://www.tecnick.com/public/code/cp_dpage.php?aiocp_dp=testimages

Contains test images, and also the octave sources.

For better understanding color spaces, color management, etc. , thanks to TJS from BlenderArtists:

http://cinematiccolor.com/

http://opencolorio.org/

http://www.oscars.org/science-technology/sci-tech-projects/aces

http://brucelindbloom.com/




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Feature Requests / Global Reset Shutter, with external mechanical shutter
« on: December 02, 2014, 02:41:06 PM »
Hi,

from an old post of a1ex :

Quote
There seems to be a global shutter for starting the exposure, but a rolling one for stopping it. It's visible on the motion blur shape from the full-res silent pictures, which matches the graphs from the other thread.

It's called 'Global Reset' and is available on scientific CMOS sensors. I was wondering if it was possible to do it, and sending a signal outside the camera for each RESET (and also the time of the shutter selected in Exposure Override), while shooting movies (either in H264, either in RAW).

WIth an external shutter it would be possible to caputre action scenes (fast moving cars, trains, chasing, rapid camera movements), flashes and gunshots' muzzle flashes, etc. I feel the camera with the rolling shutter an extreme stop to my creativity.

The ARRI Alexa Studio M works in this way: it has a regular rotary disc shutter (so it has got a conventional loupe, also).

In another thread I asked if it was possible to synch the camera's shutter with an external one, and you guys told me it was possible using the led. However I thought it was useless, because the sensor need to be reset on all lines as soon as the shutter will open (and the it doesn't matter how much time is needed to scan all the lines in rolling mode, but at least before the next global reset.).

Hope it would be possible.

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Hello,

yesterday I did a hooting for two of my syster's friends. I have Canon 600D with ML on it.

CANON 600D - Firmware Ver. 1.0.2-ml-vTL20.201

Pic Quality: MRAW+LargeFine (othe rpeople handled my camera befor emy shooting and I didn't checked for that).

When I downloaded pictures from the CF card to PC, I discovered that there are 11 jpg files (all of those are ok, except 2 wich has got corrupted lines with magenta pixels), 111 CR2 files wich can't be opened either in UFRAW, either in PS CameraRaw (UFRaw and CameraRaw both latest verison), and also 169 DNG files (???).
Those DNG files can't be opened, except for the first two, wich appears to be the first two pictures I shot.

WTF ??

I need help because my reputation is in extreme danger...

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Hi, I want to do some experiments with my 600D; even tough I think that it can be helpful for a series of applications (such as cine strobo lights), I would like to know if there's a practical way to send an electronic signal to an external electronic device (in my case, just an Arduino) to tell when the electronic shutter starts to scan the sensors lines, and when it finishes.
At least when the electronic shutters opens.

I thought that the flashmount or the mic jack (using Low-Level I/O scripting) can work? However I need the fastest synchro possible.

Thank you very much.

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Hi,
this night I was thinking about how to borrow a 5D MkIII to shoot my action short film, or what best profile+workflow to use for H264 recording if RAW wasn't possible.

Then I got an idea, about recording lossy 14 stops of dynamic range on my 600D (Rebel T3i).

I was thinking about a sort of motion JPEG, but instead of RGB JPEGs, RGBE JPEGS (Red, Green, Blue and Exponent) or something like that (or even for every frame, a normal JPEG and a grayscale JPEG for exponent). This allows hig dynamic range, so it would be possible to store the 14 bit data from sensor without clipping higligts and shadows (maintaing 14 stops instead of 8).

Then I thought that JPEG2000 supports 48 bit depth (16 bits per channel).

Also another solution would be to store 2 pictures (24 bit) per frame (one spanning form 1 EV to 8 EV, the second from 9 EV to 14 EV).

So that we will record a sort of lossy RAW. I was thinking about 600D wich is limited by the SD slot bottleneck to 20 MB/s; at this speed, assuming 23.976 fps, the maximum frame size would be approx 800 KB, and for 2-pictures-per-frame it would be max 400 Kb for piture.

The S2 size (JPEG, 1920x1280, fine compression) is approx 1.3 MB as of T3i's manual, and about 3-500 KB as of my tests. It's too high, maybe cropping 1920x800 can work.

It's just an idea, I don't know if it would be possible (I don't know how the camera works, I'm starting right now to understand that).

What does the developers think?

I think that if we can enable the T3i to shoot 14 stops dr lossy video footage, we will push the envelope on serious cinema filmmaking on cheap machines... this will push the manufactures to develop even better digital cinema movie cameras at even low prices.

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