johninderby

Ha ha. Beat me to it. 😁😁

Had the Skymax 180 but recently replaced it with a TS 8” Classical Cassegrarin as a planetary scope. Initial impressions are extremely promising and a big improvement over the Skymax. Similar weight to the Skymax and no problems with dew at all. Bit more expensive though.

If you really want to understand optical testing get hold of this book or a similar publication. Field Guide to Inrerferometric Optical Testing https://www.amazon.co.uk/Field-Guide-Interferometric-Optical-Testing/dp/0819465100

Another thing is the 6x30 has a wider field of view than the 9x50. So the 6x30 is better for finding bright things such as planets but the 9x50 is better for finding faint things. So one type is not always best. Get the one that suits your scope and what you want to observe. Then there is the Telrad vs QuikFinder argument. 😁

Depends on the brand of scope. Some use reinforcements and some don’t. The weight of the 9x50 isn’t the problem. It’s more a problem with smaller scopes where someone might use the finder bracket as a handle to pickup the scope. Have to say I’ve never had a problem with scopes that don’t use any reinforcement. Also depends on what you are looking at. For a small mak used for lunar / planetary the 6x30 is more than adequate. For a wider field scope the 9x50 is better for hunting DSOs.

APM has quite a few variations of the Concentre. https://www.apm-telescopes.de/en/othernbspaccessories/artificial-stars Accuracy is spot on. It compensates for any other mechanical missalignments and ends up with perfect optical alignment. Also can be used as a regular collimation tool. Some generic instructions. You can tell it was translated from German. 🙂 Collimating with the Newton Concenter Eyepiece This manual should be a small help to align (collimate) your Newton Telescope in a simple and practical way. When you hold the Newton Aligning-set in your hand, you will notice at the bottom side a look-through plastic-disc with a central hole and concentrically engraved rings. At the other end you will find a small single hole , that was on purpose made so small that the eye will not have a chance to be in a wrong position and as such cause a faulty alignment. After we inserted the Concenter Eyepiece, in the Focuser, you will see matt half transparent rings in front of the optical components of the telescope. 1. Align the Focuser With a covered primary mirror !(maybe a piece of paper or main mirror cover) When using this alignment set, we should pay attention to work in an environment with sufficient light. Assuming that the focuser was fitted on the telescope tube in a straight angle (90deg), we can now align (shift or rotate) the secondary mirror in that way that he becomes concentric with the rings from the Newton Alignment Set. With the focus-adjuster of the telescope we can bring one of the concentric rings into that position so that the outer side of the secondary mirror aligns with the fitting ring of the Concenter Eyepiece. By doing so, we can detect already the slightest change from the ideal position. Attention ! Your align includes the Offset of your Telescope so if you have a real middle mark on your secondary ,it is not in the middle of the concentric rings. Only if you have an Offset mark on your secondary its in the middle 2. Align the secondary mirror with the prime mirror When you look into the eye-piece you should change the angle of the secondary mirror in that way so that the bright reflection of the prime mirror in the secondary mirror is concentric with the rings of the alignment set. ! 3. Align the prime mirror to the optical axis When working in darkness you can enhance the visibility of the ring-disc by working with ,for example, with a LED-Lamp. Now the prime-mirror middle-marking can be aligned with the bright rings that are now lit up. In the beginning the reflections from concentrically rings on the reflection mirror can cause some confusion. Verify and train the mirror manipulations before you start using the Newton Concenter Eyepiece. When aligning the mirrors, we should only use the main circles from the Alignment-ocular. When you followed these instructions carefully, you will not need a final align using real stars.

Because it uses circles instead of a crosshair it is a lot more accurate. You move the drawtube in or out until one of the circles matches the outside edge of the secondary mirror. Rotate and move the mirror up or down until it is a perfect circle. This also takes care off offset adjustment. They do 1.25” and 2” versions. Takes eye of eye placement as well during setup. https://www.teleskop-express.de/shop/product_info.php/info/p5506_TS-Optics-Concenter-2--Collimation-Eyepiece-for-Newtonian-Telescopes.html

The Telescope Express Concentre is a pricy but simple device for getting your seconday mirror perfectly set up. I had thought my secondary was perfectly set up but found it wasn’t after using the Concentre. Made me realise how imprecise a Cheshire or colimation cap is for setting up the seconday position. Interstingly found my laser colimator gave much better results after setting up the secondary using the Concentre.

Not exactly astro but at least can be used despite the weather.😁 Compact PC keyboard.

SCTs are great all purpose Relatively compact scopes. Not the best at any one thing but able to perform well at most things. Had a C11 that was put performed on planetary by an OO 200m f8 newt. The 8” Classical Cassegrain is an outstanding planetary performer and initial impressions are it is better on lunar / planetary than my 10” dob. Not as good an all rounder as a C8 but on planetary in a different league..

One day would like to get an Esprit 100 or perhaps the 120? Seem like a good buy. But that’s a way off having soent enough lately. 🙂

Check Opticstar’s eBay shop as they usually have free shipping Wheras you may have to pay £5.00 for shipping if bought from their website.

The scope should be close enough to being collimated to use right away. A collimating cap is a simple cheap but helpful tool but you’ll also want to get a Cheshire eyepiece for more precise collimation. https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html Then there is a world of increasingly expensive tools available but you won’t need any of them right away. BTW the biggest mistake I see with beginners trying to collimate a scope is making huge changes to the collimation knobs and screws. Just tiny, tiny adjustments and creep up on collimation. http://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/

Perhaps inform them that lighting up the church helps the lead theives see what they are doing and encourages theft. So many think that lighting up the place deters crime when it actualy has the opposite effect. 🤦🏻‍♂️

Or go a bit over the top like this. 😁

Different colour for each one. 🤔🤔🤔

At least they haven’t turned the Forth Bridge into a light show..........yet. 😁

A one bedroom flat (apartment) in central London averages over $3,000.00 a month. 🙀🙀🙀

A pair of tube rings to bolt the handle to would work just fine.

Fitting a carry handle to the tube makes it easy to carry one handed. Here’s one I fitted to a 200p I used to have.

This is torture having to wait but certainly sounds like it’s worth waiting for. 🙂👍🏻👍🏻👍🏻😎

Wex Photographic has an open box one at a good price with free delivery. https://www.wexphotovideo.com/sky-watcher-skyliner-200p-classic-parabolic-dobsonian-telescope-used-1717199/?mkwid=sM2D1wOea_dc&pcrid=310558797769&kword=&match=&plid=&product=1717199&gclid=EAIaIQobChMImKWJxeG15QIVB1XTCh0OvAYlEAQYAiABEgIWwPD_BwE

There’s a 200p on ABS. https://www.astrobuysell.com/uk/propview.php?view=152363

Used to have the first edition years ago. Will have to see how improved the expanded second edition is. 🤔

Buying a second hand dob from someone on SGL or Astrobuysell is pretty safe and scopes are usually well looked after. Do stay away from 2nd hand on eBay, Gumtree etc as some of the scopes can be a bit dodgy. The Skywatchers have been around for ages so lots come up second hand. The Bresser is a lot newer and very rarely seem to come up for sale second hand. My Bresser 10” dob.