F3 BBC report

Also says the camera only has about 48.5db S/N ratio. That's almost the same S/N ratio they found for the EX1/3 at 47db for +3db gain. Odd. I'm wondering now if he has a typo and ment to say the F3 is -58.5db.
 
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BBC guru Alan Roberts:

"Sensitivity was not measured directly. The specification claims it to be T/11 at ISO800, and since ISO800 corresponds to 0dB gain, this means that the sensitivity is very similar to that of a 3-sensor ” sensor, which in turn implies that the pixels are about 5μm square. Given that the sensor is ‘super 35mm’ size, it must be 24x13.5mm. For the pixels to be 5μm spaced, the sensor width must be about 4800 pixels, making the sensor approximately 4,800x2,700. This fits reasonably well with the estimations in section 1.2.1, and means that the sensor has approximately 12.9 Megapixels, typical of a digital stills camera. It also explains why there is little or no coloured aliasing, and why the red, green and blue signals all have the same resolution and aliasing."

Sony themselves have published and repeatedly said that the 'effective resolution' of the sensor is 3.3 Megapixels (2.4K). Everybody knows that the pixels on this sensor are 4 times bigger than a typical SLR's pixels. This report has so many factual errors...

One of the most interesting video cameras ever released and such a sloppy report.
 
Well. He is doing reverse engineering from the data collected. Usually it tells the whole story, but with bayer masks, and DSP's the way they are now.... it seems to be difficult to tell what voodoo is happening between sensor and the card/sdi tap
 
When they measure pixels on a cmos they are counting pre-debayer pixels. Effective resolution would be measuring post-debayer RGB pixels and would also account for resolution loss caused by the lens used in the test (some lenses resolve better than others)
 
Alister Chapman on Alan Roberts F3 assessment:

"I’m really glad I got my F3 before reading the report as I have seen with my own eyes the beautiful clean images the F3 produces. I strongly recommend anyone considering the F3, but put off buy this report to take a look at the pictures for themselves before making any decisions."

http://www.xdcam-user.com/2011/03/alan-roberts-f3-assesment/
 
It seems that EX1/3 users are getting some of the best images right away out of the F3. Given the similarities that isn't a huge surprise.

The BBC doesn't regularly use such cameras as the EX1 or EX3. It is possible to get noisy images out of the EX1/3. I wonder if the BBC is just picking the wrong settings?
 
Duke M. said:
It seems that EX1/3 users are getting some of the best images right away out of the F3. Given the similarities that isn't a huge surprise.

The BBC doesn't regularly use such cameras as the EX1 or EX3. It is possible to get noisy images out of the EX1/3. I wonder if the BBC is just picking the wrong settings?
Click to expand...

The BBC allows use of the EX1/3, but usually with an external recorder. It's the 35mbps, 4:2:0 codec that's the issue. The cameras are very sharp.
 
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