Ags

Bortle is partly related to NELM - each step on the Bortle scale is nominally half a magnitude of NELM.

I always know exacly where Polaris is, but it takes a minute to pick it out from the light pollution.

The only way to get rid of temptation is to give in to it.

Forget Bortle 8, my area's gone to Bortle 11! 🤣 Lets show Bortle some love - it made estimating sky quality more accessible to many people. I am coincidentally working on indicative Bortle charts for a book I am writing. I don't cover Bortle 1 skies because those are just a myth, a tall tale told to gullible newbies at star parties!

I haven't seen the Milky Way in years. Bortle at least further classifies the awful skies with further detail.

Light leakage in the IR spectrum can really mess colors. Here is a worst case scenario - with the IMX 462, if you do not use an IR cut filter you are really imaging in IR with a little bit of color data added. Your "blue" channel would be mostly IR signal.

Before you spend any money, try focusing on a distant building during the day. That should be easier than focusing at night, and will get you close to infinity focus.

Just to underline the point, the diagonal must be used or the eyepiece will be too close to the telescope lens.

If they move around, they are bits of jelly inside your eye, commonly called Floaters. Try with a 20 or 25 mm eyepiece if you have one instead. Rack the focusser all the way out and inch it in slowly.

What is the focal length of the telescope? Is it a reflecting telescope. It sounds like you are either using too much magnification or you are way out of focus.

The pixel size is really more like 5.8 um from the point of view of resolution because of the bayer matrix, isn't it?

Very nice, some sofware teething problems last night but it is very sensitive. Dark frames show very little "amp" glow. I need to buy an IR cut filter, that's why doggy was imaged with the UHC-S - to cut the strong IR leak messing the colors. On the bright side, I expect it is a seviceable IR mono camera, which I will test on the Moon with my Wratten 29.

How about an Askar 135mm f4.5? That would be sustantially wider, faster and lighter. I don't own one and have never user one, but I am considering one for my ASI485MC.

First light... Canis Minor, Baader UH C-S filter.

I was out tonight playing with my new camera, but I did enjoy Orion and Gemini rising. M42 was washed out and almost invisible in the finder scope, but I did enjoy a color EEA view of the nebula on my laptop screen - not sure that counts?

I just bought a ZWO ASI485MC so I might have some distractions to contend with... 🤣 The book is 80% done, but the last 20% takes 80% of the effort. And then the next 20% you didn't count on takes 80% more effort!

Santa brought me a red shiny thing perfect for hanging in Christmas trees!

At the moment, I mark everything that is mag. 7 or brighter as blue, mag. 9 or fainter as red, and everything else orange. That's based on my personal experience with scopes of up to 150mm aperture with Bortle 8 skies, but I might want to tweak the rules based on objects (globulars cut through the light pollution more than galaxies, etc). Obviously, with a larger scope, you have more of a chance with red objects, while if I have my ZS66 out, I would tend to stick with the blue objects 😀

I have found my previous project Discovering Double Stars to be tremendously helpful to me, so I have decided to roll out another one for deep sky objects. After including the Messier and Caldwell catalogs, and adding in some brighter galaxies, variables, carbon stars, globular and open clusters and planetary nebulae, the book covers 389 objects covering the northern and southern hemispheres. I am tempted to include a few classic doubles as well, but that would of course duplicate the earlier book. One lack is diffuse nebulae, but I find those completely inaccessible from Bortle 8 skies, so I have only included the ones in Caldwell and Messier. I have refined the diagrams somewhat: the callouts on the left side cover less of the map, I added a border, and made most callout lines avoid crossing each other (some line crossing is insoluble however). As the targets can get quite crowded and there is a greater density of targets on many overview maps, I don't generate a finder circle per target but I do color code the target pointed by the brightness of the target (blue should be easy to spot, orange is somewhat fainter and red is difficult).

I hear the hyperflex 7-2-21.5 is quite good on doubles, particularly with the Baader Q barlow.

I'm not a big fan of swapping eyepieces, so I normally use a general-purpose 60x to 100x on most nights. This may change when I get a zoom 😀

@AstroNebulee it sees a lot of use, mostly for photography now. In alt-az mode it often has an issue with alt runaway, hopefully the new firmware will solve this.

Great thread! Bookmarking this. Here is my AZ-GTI with its various optical companions.

I'll watch the launch through my fingers.

Sounds very interesting, I might give this course a go too!