Sensor analysis - with or without filter?

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zerolatitude
Posts: 156
Joined: Mon Mar 01, 2021 5:24 am

Sensor analysis - with or without filter?

#1

Post by zerolatitude »

Hi,

I'm running the sensor analysis on ASi385MC.

I normally use a UHC filter, and wondered if this would make a difference to the analysis results. So I ran it with and without the filter, at 8 as well as 16 bits.

The results table has only very minor variations eg 3.01 vs 3.04 - basically no difference.

However, the "Sensor is linear to" number changes quite a bit. Without a filter, it is 98.5% and with it is 85.6% (and on one run down to 51%).

Would this make a difference in how the Brain computes the numbers?

Thanks
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admin
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Re: Sensor analysis - with or without filter?

#2

Post by admin »

Hi,

with or without doesn't really matter - if you have the filter on then the initial stages will end up asking for a stronger illumination level that compensates for the effect of the filter.

The linearity measurement is almost certainly varying due to variations in the light level while the measurements are being made. If you have good steady illumination then this can be accurate, but if there are variations (and even seemingly constant illumination indoor house lights can vary), it will affect the reading. The % linearity is only for information and is not used in the brain calculations.

cheers,

Robin
zerolatitude
Posts: 156
Joined: Mon Mar 01, 2021 5:24 am

Re: Sensor analysis - with or without filter?

#3

Post by zerolatitude »

Thanks
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