Optimum sensor to use with Askar FMA180Pro

Doug Crowe:
I use an asi533mc pro with mine. I have been very happy with it.

I looked at your pictures and they look great!  I have a Player One Ares-C Pro and the Askar D1 + D2 set.  This looks like a good combo.  Thanks!

I have all of the cameras listed above except the IMX676 based camera which is used by some robotic telescopes and ZWO just released a planetary version.  I have been going through my images and taking test images and I have found that the winner here that is a good balance between Etendue and resolution is the IMX183 based sensor.  With such a small aperture, I have found that with larger sensors cause loss of spatial resolution in the lower wavelength frequencies.  Living near Chicago that is basically one giant LED light, the blue to ultraviolet gets lost.  So the 2.4um pixels recover some of this resolution in the lower wavelengths.  The only issue with the camera I have which is the QHY183C, it has an IRCut window so I won't be able to use it to recover extra resolution from the near infrared that makes stars look bloated anyway.  Yes the IMX533 has over double the light sampling rate but the loss in resolution is not worth it as I want to gain as much detail as possible.  Also with my experiments with dithering and drizzling, I should be able to capture some impressive images that are sharp and full of detail.  The average seeing for my area is actually pretty good sometimes.  I can get down to as low as 0.60 arc seconds but the light pollution ruins everything which is why I am making this portable rig and selling equipment to fix up my aging van to make frequent trips to a dark site (bortle 3) about 100 miles away.

Below is a graph generated from Russ's MTF Analyzer page which is a good way to help determine the best sensor to match with my optics.  I have created a graph using the QHY183C, 1 arcsecond average seeing, and the approximate Oiii frequency which is harder to get.  I have also included drizzling as using my technique I am actually able to recover spatial resolution which is further enhanced using deconvolution.  Yes you can recover data beyond the diffraction resolution limit:

https://www.rc-astro.com/mtf-analyzer/


This was an image I took last year of Andromeda using the Askar FMA180Pro with the QHY183C.  I didn't dither the way I needed to recover resolution.  Usually I use a spiral dither with half the sensor pixel size the way it was done with the Hubble Deep Field.  I will recreate this with higher resolution and more integration time from a dark site to see how better this image can be.

This was taken from my Bortle 8.5-9 location:  https://www.astrobin.com/g8vri5/

FOVs...  I used the Player One planetary cameras but I actually have the Ares-C Pro and the Uranus-C Pro.  Both great cameras!  Fitting Andromeda into the FOV of the Uranus-C Pro would be a little tight but the lower resolution would allow for me to capture a lot of frames to get some great drizzle!  

I am on a tight budget now thanks to the US economy and having a family to support so no more new toys for me for a while.  Will also be selling some stuff to fund another project I will be working on in the future.  This setup should keep me happy for a while.