One Last Image; Winter Hobby Time: Watchmaking Resumes

I did manage to collect RGB frames to go with the luminance I had for the California nebula. You may recall earlier this year I had a miscue with NINA and spent a night collecting only L frames. I had three targets in mind, M31, the California Nebula, and M42. Now two of those are completed; M42 will have to wait.

Here is a scale version as preview; you can see the full scale version at its AstroBin page.

I think it turned out very well! Over the winter I'll probably reprocess it to apply some deconvolution and masked sharpening.

One thing I was initially skeptical of concerning PixInsight was how well it would stretch images. Pre-PixInsight I used Photoshop for this by doing iterative applications of Curves and Levels. I appreciated the way Curves gave me fine control over the shape of the stretch and I was afraid PI would be too coarse.

What I've found is that PI's Histrogram transformation is really quite effective for stretching when used to mimic the iterative application of PS's Curves and Levels. It seems particularly good at avoiding harsh edges on nebulae. (Note that I don't start with the PI's STF, I begin iterating with the linear image. And I do use PI's CurveTransformation after the initial stretch.) 

Once I become more adept at masking in PI, it's likely I'll drop the use of PS entirely.

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I'm a cold weather wimp, particularly when it comes to imaging. As much as I'd like to continue imaging right through the winter months I've come to realize I simply don't enjoy it. It might be different if I had my own observatory, but that's not possible at this time--there are too many trees and too much light pollution. Therefore I've switched to my new winter hobby as of last year: watchmaking. 

Technically, it's more like watch servicing or salvaging. Some (perhaps most) of the mechanical pocket or wrist watches you find don't run well if at all. For many of these it's simply because they've never been serviced or their last service was decades ago. Even if the watch has been kept clean and dry internally solidified lubricating oil can provide enough resistance to disable a watch. 

It's sometimes possible to rejuvenate these old watches with a good cleaning and re-oiling. That's where I come in. What I've been doing is finding watches on Ebay to work on. Last year I mainly disassembled and reassembled older non-working pocket watches to learn the basic process. This year I've obtained some working examples that run, if only somewhat, and will see if I can tune them up to run halfway well.

I'm taking a short class from a local watch repair shop in January, and slowly building up my gear. Last year I purchased the basics; this year I've added proper oils and a device called a timegrapher. Timegraphers assess mechanical watch performance so that I will have an objective measure of any improvement my servicing provides.

I'm currently working on a Waltham model 1890 that was made in that year. Yes, it's 132 years old. It works, but poorly. I'll have more about it in my next post.

Bumps on the imaging highway; more (unfinished) images

This is astrophotography, so things are never as easy as one hopes. 

At the beginning of September I had an all-night imaging session at the club's Eagle Lake Observatory site.  I was trying to do a few targets: M31, The California Nebula, and because a little time was left over as the dawn was approaching M42. Let's start with the latter because it illustrates the main issue.

I had only about a half an hour before the morning sky started to really brighten, so I set up NINA to do five 90-second frames for each LRGB channel. Here is the initial stretched result:

 

 

I did say LRGB, but this is mono! It turned out I took 20 L frames; the mystery is how that happened. I wish I could tell you, but I don't know the actual cause. My best guess is that NINA lost contact with the filter wheel and couldn't execute the filter changes. So this is not quite the image I wanted, but eventually I'll be able to shoot the chroma and make a nice image.

 

The same thing happened with my California Nebula frames and I've got 96 L frames which should make for a really nice eventual image. Here's a quick processing of the luminance frames:

 

This seems to have started as soon as I began imaging M31, as those are all (so far as I can tell) luminance frames. All 125 of them! I can say this from the early look at the M31 stack that if you want a very smooth background, shoot 125 frames! This is a first look at the luminance image, where I've somewhat de-emphasized field stars using PixInsight's Morphological Transformation:

 

 

Incidentally, these are all imaged using the Takahashi CR 0.73X focal reducer on my FSQ-106, so I was operating at  f/3.65 and an effective focal length of about 387mm.

 

Another mystery was easier to solve. I noticed that autofocusing was having a very difficult time. This was traced to a loosening of the connection between the motor and focuser shaft. I've tightened that up now, and just in case that was happening because of overly tight parking of the focuser I'm going to change the focuser's home position.

 

This weekend I hope to actually collect the M31 chrominance, and maybe deeper into September get the California Nebula color data.

 

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I'm returning to something I started back in 2020: spectrographic imaging. More about that next time (I hope!)