Hi,

I wonder is there is a way to practice indoor to calibrate, collimate, test autofocus, test guiding, ... etc without waiting for a clear sky night?

The reason for this is that where I live, I have only 2-3 hours at night before midnight, and it is usually cloudy. I want to be ready for targets when I get the chance and not to spend a lot of time doing basic operations.

Any ideas would be appreciated...

Thank you
Mohamed

You can create calibration frames (to a point) during the day, especially if you have a temperature-controlled camera. I do that all the time. I also use a fixed output light source and ND filters for flats.

For final collimation (based on reading and not experience) you need real stars. The same applies for autofocus and guiding. You can test that your focuser works as intended by manually focusing on something far enough away. For my 80mm refractor, I have had to extend the focus tube about 9mm further for a nearby target than for stars.

Richard

Hi Mohamed,

Generally speaking, you can train your skills with Kstars/Ekos using the different simulators. You can also install GSC which is a catalog of stars. The simulators know how to use the stars from GSC so when you need to test new things in Kstars, you are not stuck every time you need to take an image. (focus, align and polar align, use the mount etc...)
Of course you can't really correct the errors or the focus, but still, it's really useful to save time. It's a bit like a flight simulator : it's not enough to learn how to really fly a plane, but at least, when you get on the plane, you already know the purpose and the use of all the instruments.That makes you more self-confident.

- Marc

One thing I do is use some of my older images to test the plate solver as well. I get everything hooked up then go through the calibration routine, use kstars to slew the scope around, use my previous images to plate solve and slew to target. As far as guiding, camera, and telescope, I set those to simulator and do different tasks. (Focus, exposure, solving) Without real stars this is about a good as it gets.

Regards
Jim

I second what Richard said, I just figured out I can do my darks/bias inside. I didn't think I could find a dark enough spot and cool enough. Turns out I have a nice corner of my basement which, with the right black coverings, is perfect. Plus I was surprised to see I could get my 1600mm down to -20C. I did have to string an ethernet cable down there... the wifi is just not strong enough.

I'm not doing my flats inside as they are quick enough to do in the mornings. But not having to do darks at night is wonderful!

Oh and since I just also figured out binning... I have to create a whole new library of darks. Oh well, it's do-able now.

Thank you, Richard, Mark, Jim, and Megiddo for the nice practical ideas.

I just want to add that I discovered that I can do the collimation as well using Hubble artificial star.

I really appreciate your inputs. Will keep me busy on cloudy days during the lockdown.


Thank you
Mohamed