Question: Sequence Planner and BIAS Frames

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Brian1973
Posts: 28
Joined: Tue Jul 14, 2020 9:32 pm

Question: Sequence Planner and BIAS Frames

#1

Post by Brian1973 »

After using a DSLR for the past couple of years, I recently purchased an AA26C CMOS and switched from APT to SharpCap Pro. Setting up the Sequence Planner for taking lights and darks is straight forward, however, I can't seem to figure out how to use the Sequence Planner to complete bias frames.

When I used APT, it was a matter of just selected the Bias frame tab and inputting the number of exposures and that's it. I have tried searching in the manual regarding taking bias frames but have not been able to locate the information. I was wondering if someone could point out where in the manual it provides the instruction on how to setup bias frames or share with me how to do this step.

Best,

Brian
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Re: Question: Sequence Planner and BIAS Frames

#2

Post by admin »

Hi Brian,

first, setting up a bias frame capture in the planner would be like this:

* Set frame type to Bias in one of the rows
* Set the number of frames to capture
* Tick the 'override exposure' box and set the exposure to minimum for the camera (say 0.0001s) - 0.1ms
* Either set the filter to 'dark' if you use a filter wheel and have a black filter or check the pause before and pause after options to allow you to cover/uncover the scope.

But...

my understanding is that bias frames are only useful if your dark and light frames are of different exposure lengths (the bias allows the dark to be corrected for the different exposure on the light frame). If your dark and light frames are taken with identical exposure then bias frames do not add anything to the processing of the image.

cheers,

Robin
Brian1973
Posts: 28
Joined: Tue Jul 14, 2020 9:32 pm

Re: Question: Sequence Planner and BIAS Frames

#3

Post by Brian1973 »

Thank you Robin for providing this information. When I attempted to set this up myself, I couldn't get it to take the right exposure lengths.

I also appreciate your insights regarding bias frames. I wasn't aware of this information.

Best,

Brian
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