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The content: As I wrote before, Mastering PixInsight comes as a two volume set, the main book and a reference guide. To start with the latter, the reference guide contains a description of all the processes in PixInsight in alphabetical order. These descriptions are divided into three sections: an introduction, "When to use ..." and "Parameters". Some descriptions are short (how much can you write about "Invert"?), while others go as long as 10 pages (MultiscaleLinearTransformation, StarAlignment, SubframeSelector). While the reference guide is thorough, it is best used together with the main book. Andreo's decision to publish the reference guide as a separate volume, makes it easier for us to read the specifics of any process when we use that process in a workflow. The main volume is what Mastering PixInsight is all about. Rogelio Bernal Andreo presents PixInsight in two passes. After a first quick glance of the program and the user interface in chapter 1, he presents a complete workflow in chapter 2. These two chapters are mainly for the novice user. They develop a basic understanding of how PixInsight works and how it differs from other image processing software. Chapter 2 presents a basic workflow which a beginner can apply to his/her images and get a pleasing result. The most common processes are introduced, from sub frame calibration all the way to final sharpening and noise reduction of the post processed image. This first pass takes up only 90 pages of the book, enough not to be too overwhelming for the first time user. The second pass takes the remaining 300 pages of the book. The author revisits the user interface in more detail, and presents some of the lesser known features of PixInsight, such as Process icons, and Image and Process containers. He then uses two long chapters to lay out a detailed workflow with more advanced use of previously covered processes, as well as new processes. Chapter 4 covers pre-processing, which is defined as the calibration, registration and stacking of sub frames into master images, as well as the processing of these master images up to non linear transformation (stretching). Chapter 5 describes various ways to stretch images. It also describes more advanced processes such as HDR composition, narrow band image processing and LRGB processing. Here the workflow is not as clear as in the first part of the book, and it becomes clear that this part is aimed at the more advanced user of the program. Chapter 6 comes as a bit of a surprise. So far, image processing in PixInsight has followed a sequential workflow, with one process being applied after another. In chapter 6, Andreo presents a parallell workflow, involving PhotoShop or GIMP. The idea here is to import different versions of images that were processed to optimise a specific feature (eg, noise reduction in the weak parts, hdr compression or sharpening in the stronger parts), and combine these images as layers in GIMP or PS. Andreo presents details on how to implement such a parallell workflow. Finally, chapter 7 rounds up the book. Various ways to save and/or print images are described. Depending on how you want to present your final image, you will have to make decisions about sample format, colour profile, and image format. This chapter is all about that. What I like about this book: Andreo's decision to make this a two volume book, where the reference guide is separate from the main volume, makes it easier to read about a specific process while you read how to use it in the main book. You don't have to flip back and forth to look up details of a process. Also, when you work independently from the main book, it's nice not to have one tome to handle. (Together, the volumes are almost 650 pages.) I also like that he presents PixInsight in two passes. The beginner is not overwhelmed by a vast amount of information, while the more advanced user can skip the basic stuff at will. This makes for easier reading for both. In the second pass of image processing, Andreo brings us to the next level: combining process steps to achieve a desired result, rather than just applying one process to get something "good enough". This is where other books and tutorials are lacking, imo. What I missed: I would have liked to see more of multiscale image processing. Andreo wrote a chapter in "Lessons from the Masters" about enhancing weak signal without pushing the noise with the help of multiscale processing. Multiscale processing is a key feature of PixInsight, and I guess a whole book could be written about the subject. In Mastering PixInsight, he uses it on occasion (sharpening, noise reduction). Still, I wouldn't mind if he had explored this technique in more detail. Another aspect of PixInsight that would cover a whole book is PixelMath. This is a very powerfull tool that allows exactly what it says: to manipulate an image on the pixel level. Andreo shows in an appendix, various expressions to mimic layer combination of GIMP and PS. PixelMath is also very good at creating or combining masks. Besides a section in the reference guide, and one in the main volume, the use of PixelMath is spread across the book. Here, an index would have helped the reader, imo.

In the days before so called ion assisted deposition, filters were made by evaporating metal oxides onto the glass substrates. This produced films that had a lower density than bulk material. In other words, composition wasn't always accurate and films consisted of grains. In time, water vapour could creep inbetween these gains and cause the films to deteriorate and possibly peel off. Also, to make evaporated films stick to the substrate in the first place, it was absolutely vital to clean the glass substrate thoroughly. Nowadays, the glass substrate is bombarded by ions while the oxides are deposited. This helps pack the individual atoms, creating denser films, without grains. So there is no way water vapour can penetrate the films. Also, the ion beam is turned on before the deposition starts, and knocks any contamination off the substrate, which makes it easier for the films to bond with the substrate. Unless something goes wrong during production (especially in the glass cleaning stage before deposition), modern filters should never fail. @steppenwolf: great image, btw. I also am eager to see the colour version.

If you don't do anything about it, it can become bad, I think. That is going to be paradise for fungus. I don't know much about refractors, but imo, you should consider taking the main cell out and slowly dry it in a warm place.

I use arcsinh stretch for rgb images, and follow up with curves stretch. Here, I pin the high end of the scale so the curve is straight for values I don’t want blown out, and only stretch the lower end. For L, I use histogram stretch in several iterations, with the midpoint slider at 0.25, until I get a pleasing image with a weak background. Then I switch to curves as per above. Sometimes I use multiscale hdr transform with a 50% mask to reduce overly bright areas a little. This workflow allows control over bright and dark areas. HTH,

Today, my hard copy of the book arrived. Of course Mastering PixInsight will be compared to Inside PixInsight, by Warren Keller. To start with, here's the physical comparison. Andreo's book is a two volume edition, which comes in a box. One volume is the main book, Mastering PixInsight, while the other is RBA's PixInsight Process Reference Guide. Other (physical) differences: Inside PixInsight is a paperback, published by Springer as part of the Patrick Moore series. Mastering PixInsight is a soft cover bound book, published by Andreo himself.

Are you sure you’re not aligning on hot pixels? Try increasing the noise reduction levels and noise scale/layers. Or, post the two images here, to let us have a go at it. Seeing the real data is always better than trying to guess what may have gone wrong.

My version.

Before you put a t-shirt over the scope, make sure it points at the sky only, for example zenith. No trees in the foreground. You want a very even illumination to start with.

Have you tried setting the position/time for the flip to occur further away from the meridian? Also, check on the indi forum for possible solutions.

If I count correctly, fourteen images within one month with this combination. You're delivering both quantity AND quality. Great set of images. But please, please, do leave us some photons. 😋

That sounds like a typical imaging night. At least now tou know which button to press next time.😉

The normal workflow for the scheduler is to take exposures until any one of its stop criteria is met. If you activate the park sequence while scheduler is running, this will ruin the sequence. There is no checking in the scheduler that the park time is set. Ie, if you plan to use scheduler, you should give it ultimate control over your rig. As I understand it, the time park feature is exactly the way you described. If you don’t use the scheduler, but want to park your mount unattended at the end of an imaging session, you would use this feature. Remember that Ekos consists of modules that were developed independently. The idea behind indi is that drivers and clients can be distributed. You can use one client for mount control, another for camera control, and yet another for guiding. But for each client to know what any other client (module) is doing at any time, would be difficult to implement. Consiser Ekos to be a toolbox where each module is an indi client, rather than Ekos being a single program. You only use those Ekos modules/clients you want, and can use other software/clients at the same time for other tasks. If you have Pixinsight, for example, you can use both Ekos and the indi module in Pixinsight at the same time to control your mount, or camera. Now THAT’s a recipe for disaster.

A newtionian with a large chip camera, a barlow, but no coma corrector is a sure way to get coma and colour abberation in your images. With this combination, you really need a coma corrector. Also, the Barlow, unless it’s a top quality one, will introduce som chromatic abberation. To verify if collimation is a problem, take an image of a defocused star. The doughnut should be symmetrical with dark shadow accurately centered.

I think I will try it at the next opportunity I have.

According to the manual, it does, although I have never used this feature. It should not be used together with the scheduler. The clock display next to the start button is a count down timer. More info here https://stellarmate.com/support/ekos/17-support/documentation/ekos.html

Actually, the section you show is not part of the code as I have it on github. Did you copy and paste this from a webpage? If so, I think you also copied a section of html. This is a link to the code https://github.com/wberlo/Arduino_Moonlite_Focuser/blob/master/Arduino_Moonlite_Focuser_V1.ino

I'm not sure. The code you have there looks like html, and could be part of a file which I adapted. I will have to look into it.

The jury is back with a verdict: Now that I have the parameters dialed in, the new routines are definitely going to be part of my toolkit. I don't think I'll be using PHD2 anymore. I do like the user interface of PHD2 more, and all its gadgets, but the internal Ekos guider now works equally well and is actually easier and faster to get starting; more "push here, dummy" than PHD. And I can still use phd log viewer to analyse my guide logs

Another clear night this week allowed me to do some more testing and collect luminance data for this target. This is the original RGB image with added LRGB using 72 minutes of luminance (36 x 2 minutes) The added luminance gave less noise and tighter stars. (click on the image to view the full size version) Enough testing, next clear night I'll be aiming at something more interesting.

Regardless of colour theory, I also like the fiery look of this palette

Excellent image, Ciarán. Leaps and bounds ahead of what I produced.

A sizeable sports bag probably. Or as already mentioned, a dovetail on top to act as a carrying handle.

Apparently there are also many ways to skin a fish.

Probably. It will get ”more worse”, 😉, for us than for you.

Yes, the second image is better. It has the nebula pop.