Danua's White paper on Starlight

eman

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Attached is Dahua's White paper on Starlight
I have a question or 2 on the paper.

Is Smart codec considered to be H265+ ?
Will Blue Iris 5.0 handle 265+
I have tried to set the 2831T-ZS smart codec to on and
Blue Iris seems to handle the live view OK but not the recordings
especially at night.

Why is it that Camera manufacturers cannot squeeze a 4/3 or APC-C
sensor into a full bullet or even a mini bullet. The diagonal of a
4/3 sensor is 21.6mm and the diagonal of a 2831T-ZS is approx 50mm
My old Sony 5n camera has an external diameter of 60mm with an APS-C
sensor. I know that Dahua has a box camera for their 4/3 sensor so I assume
there is some sort of space limitation but maybe someone can enlighten me.
 

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fenderman

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Attached is Dahua's White paper on Starlight
I have a question or 2 on the paper.

Is Smart codec considered to be H265+ ?
Will Blue Iris 5.0 handle 265+
I have tried to set the 2831T-ZS smart codec to on and
Blue Iris seems to handle the live view OK but not the recordings
especially at night.

Why is it that Camera manufacturers cannot squeeze a 4/3 or APC-C
sensor into a full bullet or even a mini bullet. The diagonal of a
4/3 sensor is 21.6mm and the diagonal of a 2831T-ZS is approx 50mm
My old Sony 5n camera has an external diameter of 60mm with an APS-C
sensor. I know that Dahua has a box camera for their 4/3 sensor so I assume
there is some sort of space limitation but maybe someone can enlighten me.
smart codecs are proprietary and usually adjust the iframe interval to minimize bitrates and are not compatible with blue iris.
The 4/3 sensors will eventually come in the smaller cameras.
 

mat200

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Hi @eman

4/5" sensor - significantly larger than the others currently in those cameras.

From an engineering point of view - there's a lot more going on in the case with all the parts as well has how well the case can handle the thermal dissipation of the components in the sealed case, so it's not just the size of sensor that must be taken into account. As they can make the other components smaller and more energy efficient we may see larger sensors in similar sized cases.
 
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cb8

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And with larger sensors the lenses will have to be physically larger too. The 12mm F/2 (focal view comparable to a 4mm on the 1/2.8" Starlights) lens I have on my 4/3 Dahua is significantly larger than lenses in the usual 2MP starlights. Longer focal lengths at the same aperture would require an even larger frontal element.

Another challenge with a large sensor like this is that the depth of field becomes narrower when focusing distance, aperture, focal length are all the same. A 1/2.7" sensor (dofsimulator.net does not have a 1/2.8" option) @ 4mm f/1.6 focused at 3 meters has reached hyperfocal distance behind the subject and has usable focus up to 1.7m in front of the focusing distance.

A 4/3 sensor with a 12mm lens and F/1.6 focused at 3 meters is only in focus about 1 meter in front of the focusing target and 2.8 meter behind. To get the same depth of field, you would have to set it to about F/5.0. That's a 3 1/3 stop difference, i.e. you would need more than 8 times the light in order to compensate for the aperture if we assume that the lenses' light transmission (T-stops) are the same as the F-stops (likely not true, but close enough for our purpose).
 
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