FS700 RAW dynamic range (calibrating Sekonic L-758 light meter)

paulcurtis said:
How did you record these values? Can you PM me and perhaps show me the file that you used? I can send you a raw data grey scale bayered 16 bit tif of the file, decoded through the DNG SDK to compare with.

Because i'm sure the actual engineers that developed the Bolex would love to know how you're doing this too and i can forward it on.

Seriously though, your theory is fine, but your quantative starting point appears dubious.

I'd love to be wrong but i'd spent months going through all this, multiple times, in multiple ways...

That's exactly why Sony uses 16 bit linear RAW for the F5 and F55, that's the primary differentiator between the FS700 and F5. If we were dealing with files as you suggest we wouldn't require anything like that.

cheers
Paul
Click to expand...

The file code tells a different story. It is not linear code. It is linear light. This is not theory. It is the actual file code. It is not mathematically possible to get the 21 different gray scale values I read from the image in the 2 stop value range in the table from a 12 bit linear file. The Bolex records a 12 bit 3dB per f/stop gamma encoded file. The code values correspond to the linear 16 bit first stage AD values for gray scale resolution, but the recorded file is not 16 bits. The code values at the top of the scale also correspond to 12 bit gamma code linear light values.
 
I'm PM'd you, i'd like to understand what you're seeing and why it is so different from what's in front of me... might be easier off forum

cheers
Paul
 
The top 7 stops of all sensors take up 99% of the sensor's capacity. All additional stops, along with the read and other noise, must fit in the bottom 1%.

Nothing can be done with the Full Well Capacity (FWC) of a sensor once manufactured, so the name of the DR game is noise reduction/tolerance.

The total number of usable stops is really subjective and depends upon how much noise you are willing to tolerate.

Cheers.
 
Long story short, the Sekonic software gave me a range of about 9.9EV.
Click to expand...
Hi Josh,
the Sekonic software only gave me only 7 stops haha. I did something wrong.
I recoded in raw and then used the DNG files and opened them in the raw viewer in Photoshop. I just saved them the way they were.
I put it in the software using the Advanced Mode.
How did you do it?
 
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