Sensor Analysis for a DSLR - What F stop?

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jd999uk
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Joined: Tue Jan 04, 2022 1:57 pm

Sensor Analysis for a DSLR - What F stop?

#1

Post by jd999uk »

:lol: Sharpcap Newbie here. :mrgreen: I'm currently doing a Sensor Analysis on my Canon DSLR and lens and I'm wondering whether it's important to set the F stop to wide open or not? Obviously this will not affect DSLR users who have attached a telescope to their camera, but most (all?) Lenses have a sweet spot that is quite often a stop or two down from wide open. As this analysis is required for the smart histogram, I assume it's important for any variable settings to be consistent.
Or am I overthinking this?

Regards,

John
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Re: Sensor Analysis for a DSLR - What F stop?

#2

Post by admin »

Hi John,

When you run the sensor analysis you are testing the characteristics of the imaging sensor - how the light gets to the sensor doesn't really matter (you could run it without a lens, except you would then get dust all over your sensor most likely). That means you can run it at whatever f-stop you like, it will not affect the results.

Two things to consider though...

1) Use the f-stop adjustment in the first stage when you are trying to get the right brightness level for the analysis to proceed - it's much easier doing this with the aperture than trying to change the lighting level

2) Don't touch the f-stop after that point as a number of the steps rely on constant illumination levels for proper operation.

cheers,

Robin
jd999uk
Posts: 2
Joined: Tue Jan 04, 2022 1:57 pm

Re: Sensor Analysis for a DSLR - What F stop?

#3

Post by jd999uk »

Hello Robin.

Thank you for the swift response. I'll forge on with the analysis. I didn't want to waste a lot of time to find out I had a setting wrong as this is a lengthy process!

Cheers

John
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