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Does anyone have any camera settings information for a Sony A99ii?    Anyone using a Sony A99ii on their scope?
Twah_Pisto Does anyone have any camera settings information for a Sony A99ii?    Anyone using a Sony A99ii on their scope?

Hello,

I'm sorry this sat here so long unanswered, but I was hoping someone with more info would post. I presume you have the most basic information, such as the number of pixels and pixel size, as those things are usually easy to find. The bit depth can be set to 16. Dark signal and read noise are harder to come by. I suggest doing a Google search for those, as it often requires an actual measurement by someone who owns the camera. The Gain is tricky because when you change the ISO you are essentially changing the gain. The best way forward on that, without doing careful bench testing, is to select a typical gain of 2 or so.

The hardest part is always the spectral response. I have attached a graph from this web site:
http://www.gujinwei.org/

[attachment=6]

This is somewhat out of date, but as you can see most unmodified digital cameras have a similar spectral response. You can assume a newer model will be near the top of this range. But this is the relative response, so we need a way to turn it into an absolute response to put the numbers into SkyTools. What we need is the QE for the detector, which will correspond with the peak of the graph.

Based on the extremely useful page here:

http://www.clarkvision.com/imagedetail/d...e.summary/

I would estimate maybe 80% QE. Taking 80%, and the upper envelope of the first graph I get a generic response that looks something like this:

[attachment=7]
(2017-11-17, 06:51 PM)theskyhound Wrote: [ -> ]Hey Greg,

I royally screwed up the reply! and then lost it. 

I appreciate the reply.  I have the sensor data, just didn't know what to use for the QE and the rest of the sensor data.


If i ever find out the exacts, i'll send you the data so you can update the database.
Thanks as always
Mike












Twah_Pisto Does anyone have any camera settings information for a Sony A99ii?    Anyone using a Sony A99ii on their scope?

Hello,

I'm sorry this sat here so long unanswered, but I was hoping someone with more info would post. I presume you have the most basic information, such as the number of pixels and pixel size, as those things are usually easy to find. The bit depth can be set to 16. Dark signal and read noise are harder to come by. I suggest doing a Google search for those, as it often requires an actual measurement by someone who owns the camera. The Gain is tricky because when you change the ISO you are essentially changing the gain. The best way forward on that, without doing careful bench testing, is to select a typical gain of 2 or so.

The hardest part is always the spectral response. I have attached a graph from this web site:
http://www.gujinwei.org/



This is somewhat out of date, but as you can see most unmodified digital cameras have a similar spectral response. You can assume a newer model will be near the top of this range. But this is the relative response, so we need a way to turn it into an absolute response to put the numbers into SkyTools. What we need is the QE for the detector, which will correspond with the peak of the graph.

Based on the extremely useful page here:

http://www.clarkvision.com/imagedetail/d...e.summary/

I would estimate maybe 80% QE. Taking 80%, and the upper envelope of the first graph I get a generic response that looks something like this: