johninderby

Second the 8” Classical Cassegrain.

Loved my old Skymax 180 but my new 8” Cassegrain is much better. Will take far higher manification and is sharper with more contrast and better resolution and  is only slightly heavier than the 180. The stock Crayford is not bad at all but I replaced mine with a BaaderSteeltrack refractor focuser.One of the biggest advantages though is the freedom from dew. Never had any dew what so ever.

Well worth spending the extra. Also higher build quality.

While a saddle is included it is not that good. Most replace the stock saddle with a much higher quality one such as this one that acepts both Vixen and Losmand doetails. 

https://www.firstlightoptics.com/sky-watcher-mount-accessories/adm-dual-saddle-upgrade-for-heq5-neq6-avx-zeq-ioptron.html

There were the Celestron 80 and Orion 80 with FPL53 but basicly the same as the Skywatcher. Same objective was available in the Celestron Onyx in a better OTA. The WO Zenithstar 80FD was also FPL53 and widely regarded as as being a bit better than the Slywatcher..  

A lathe is even better to hold the laser. Less error than a V block. Of course I have heard that not eveyone owns a lathe though. 🙀

Print out a bullseye on thin paper and place it over the objective. Bit of experimenting needed to get it printed at the right size though. Then the laser will show a dot on the bullseye and you can then see what adjustment is needed if any to centre the dot.

Photos of a Skytee I used to have. That is untill one end fell off. 🙀

Lesson..........don’t put too heavy an OTA on it. Keep OTA weight to about 10kg or less and it will be fine. 

The Skytee is a great buy and performs very well for a budget mount but the AZ100 is so much better in every way. Not just a piece of engineering art but a joy to use. Bit like the difference between a Kia and a Ferrari. Both do the same job of getting you from A to B but that’s where the similarity ends.

Laser should be tightened like an eyepiece. Must be firmly held to be acurate. 

Lots of EQ platforms from Telescope aexpress to give you an idea of what is available. From not too expensive to expensive such as the Geoptik.

https://www.teleskop-express.de/shop/index.php/cat/c20_Mounts-----Equatorial.html

Not difficult to build yournown though. Just Google DIY EQ platforms.

Usefull little item to have tucked away in your spares box. 👍🏻

The inexpensie lasers rarely are even close to alignment as received. No excuse for not including colimating procedure for the colimator.. I found putting the colimator in a lathe and shining the beam through the headstock works perfectly. Worth mentioneg though to remember to check your focuser for being square to the tube and that the drawtube doesn’t twist or shift out of line when moved.

Now use a Hotec which is properly colimated from the factory and is self centering. 👍🏻

22 minutes ago, Grierson said:

Seems as if I was trying to be too clever! The ASIAIR Pro actually comes with a dovetail fitted. 😥

Hope you didn’t get round to ordereing the eBay dovetail yet then. 

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The CN link  isn’t working for me. Just get you don’t have permission to view this espite being signed on to CN.

Anyway have the Kindle version of the book which is handy to have on my iPad.

I’ve been recommending Sticky Stuff Remover for years.. Works and no nasty smells and it doesn’t harm skin. Works well on upholstry and clothes as well..

I recently  refelted some rings with some of FLOs flocking. 

You do enjoy the challange of building something out of the ordinary. 👍🏻👍🏻👍🏻

Hope it all goes according to plan. 🙂

Hmmmm.......A paintball gun with red paint to turn the spotlight a dull red perhaps. 😁😁😁

One problem with the Revelation az roller setup that can occur is if it is greased which can stop the rollers from turning properly. Just WD40 or something similar sprayed on and wiped off is all it needs.  

Nice to see your post👍🏻

Will be interested to see how you get on with the Nexus DSC. I might go with the Nexus II sometime in the future. Let Rowan know about the tray holding knob and I’m sure they’ll come up with something better. 

An idea for Rowan. A quick release counterweight safety knob? 🤔

Yes that ADM saddle looks a bit anemic doesn’t it. I had one from my old Skytee but it’s now sitting on John’s Skytee.😁

The usual clouds that came with the mount have meant no proper outing yet but just looked outside and it looks like it’s clearing. 🙏🏼

I’ve not heard anything about the Tal Apolar 125 in ages. Some dealers still show it as available though. 

What you might look like after collimating one. 😁

Basicly Barlows are a simpler design and magnification varies depending on the distance between it and the eyepiece or camera as the light path is a cone. With a telextender (sometimes called a focal extender) magnification is the same no matter what the distance is between it and the eyepiece / camera as it contains extra elements to straighten the light path.

BTW the ES extender is a great bit of kit and pretty well as good as the Televue Powermate in most scopes. Highly recommended.

If you want more detail.

https://www.telescope-optics.net/miscellaneous_optics.htm

Replacing the az bearing with a roller bearing will help a lot.

https://www.teleskop-express.de/shop/product_info.php/info/p1646_Azimut-Roller-Bearing-for-Dobsonian-Teleskopes-D---320mm.html

The lazy susan aproach is a lot cheaper but requires adding some riction to the movement to stop the scope just spinning at theslightest touch.

You could also replace the alt bearing with a friction bearing.

https://www.teleskop-express.de/shop/product_info.php/info/p6767_TS-Optics-Friction-bearing-for-altitude-axis---for-ATM-mount-and-Dobsonian-construction.html

There are a lot of threads on low cost modding your dob so do a search if you don’t mind a bit of DIY. Adding a handle or knob at the top end of the scope makes it much easier to control.

Simple. The scope is made by GSO. and GSO says the reflectivity is 96%.

Get yourself a Concentre. They are available in 1.25” and 2” versions and absolutlely nothing else does as good a job of setting up the secondary mirror. Having a properly setup secondary is key to good collimation.

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p5506_TS-Concenter-2--colimation-eyepiece-for-Newtonian-Telescopes.html

A regular Cheshire eyepiece is better than nothing and will help get the secondary close enough to allow using the laser to finish the collimation but if you want the best collimation get the Concentre. It’s one of those tools that once used you won’t go back to a Cheshire.

FLO does have an extended return time at Xmas to allow for things bought earler for Xmas but that couldn’t be used until Xmas. 

You will have no problems with returning it to them. just contact them and they will organise the collection for you.