johninderby

15 minutes ago, Davesellars said:

Wait..  what??? the focuser is not straight?

The stock focuser is a basic crayford and not as precise as the Steeltrack. The drawtube isn’t as well supported. 

The stock focuser isn’t terrible but suffers compared to a Steeltrack.

Yes you need this adaptor.

https://www.firstlightoptics.com/baader-diamond-steeltrack-focusers/baader-steeltrack-diamond-rt-adapter-m90x1-for-refractors-gso-rc-scopes.html

49 minutes ago, vladmanm said:

John, did you upgrade to the RT or SC version of the Baader focuser?

It’s the RT version. Just need the one extension normally. If imaging you might need another one.

Found this statement in a article on telescope performance by Thierry Legault.

“Because in the image quality field, obstruction is the tip of the iceberg. The photographical and electronic amateur production shows us that almost all working instruments are not limited by the obstruction but by other causes like misalignment, thermal equilibrium defect or bad focusing, often at a level where obstruction becomes a negligible phenomenon. The qualities of an instrument are not limited to its obstruction, there are more important factors in practice: easy thermal equilibrium, image stability, reliability of the focuser, reliability of the optics supports, etc.”

CO is just one factor among many others that affect performance of a telescope. 

Remember when calculating the obstruction of a scope you need to take the area of the obstruction and not the diameter of the obstruction which gives very misleading results. 

The effect of a central obstruction is probably the most misunderstood subject in astronomy. It has far less effect than is commonly believed. The CC has great contrast and probably better than a 4” frac. There have been tests where users were unable to detect the effects of central obstruction.

AeroShell 33 is about the best grease available. Rowan use it to lubricate their mounts. You won’t find it your local shop though and will have mail order it. An aircraft maintenance place will have it but not in small quantities..

With a long frac then yes an extension is needed.

Yes just take your time. No need to hurry. Every scope has it’s good and bad points but you will find the best compromise for your needs.

BTW find the increased aperture of the CC gives better resolution than a 4” frac on the moon and as to central obstruction just a total non issue to me.

I”ve had small maks and SCTs and have now settled on a Classical Cassegrain for my grab’n’go setup. Bit sharper on axis than the mak or SCT and no problem with dewing and quick cool down and a proper crayford with dual speed focusing.

https://www.firstlightoptics.com/telescopes-in-stock/stellalyra-6-f12-m-crf-classical-cassegrain-telescope-ota.html

BTW the photo of the front of the scope on FLOs website is wrong as it shows the RC with it’s much bigger central obstruction. Due to be updated when they get the time.

If you want a frac then something like this might suit. Great optics and build quality and more expensive but a good all round scope..

https://www.firstlightoptics.com/telescopes-in-stock/starfield-102mm-f7-ed-doublet-refractor.html

The CC, mak or SCT have a narrower field of view but ideal for lunar / planetary and small DSOs Also easier on eyepieces so less expensive ones can be used.

I use the 6” CC as my grab’n’go scope and also have a 5” APO and on the moon they are pretty equal however the CC can be used on a smaller mount than the 5” APO so better for grab’n’go and way, way cheaper. 🙂

The mirrors in the CC are quartz with a dielectric coating so pretty tough and last indefinitely without degrading. Holds collimation about as well as a mak. Never had to touch the collimation on mine and still spot on. I find a 7mm eyepiece works nicely although have used a 4.7mm when seeing is very good. 

The CC will have better resolution than the 4” frac and contrast is surprisingly good as well. Find the CC design has the edge over a mak or SCT in on axis sharpness and contrast.

I have upgraded the focuser to a Baader Diamond Steeltrack. The stock focuser is usable but no Steeltrack. 🙂

Be arefull what car polish you use. You need a pure wax free from additives. The best wax to use is Turtle Wax Original as recommended by Obsession among others.

https://www.amazon.co.uk/Turtle-Wax-50187-Original-Shell/dp/B00068OL1A/ref=sr_1_7?crid=15PT67FD21NT&keywords=turtle+wax+original&qid=1644746912&sprefix=tirtle+wax+ori%2Caps%2C99&sr=8-7

Nice shots with good detail.  👍🏻

Was raining here last night but chance of some clearish skies on Monday. 🙏🏼

The ZWO ASi462McC is a newer camera rhan the 224 with greatly increased IR sensitively and lower read noise so worth considering.

https://www.firstlightoptics.com/zwo-cameras/zwo-asi-462mc-usb-30-colour-camera.html

31 minutes ago, Stickey said:

God, I hate smart text 😳

First thing I do with a new phone is turn off predictive text  / auto correction. 😁

The Bresser power tank perhaps🤔

https://www.bresseruk.com/Astronomy/BRESSER-Portable-Power-Supply-100-Watt.html

They do a much higher capacity power station as well but £££££££££ 🙀

https://www.bresseruk.com/Astronomy/BRESSER-Portable-Power-Station-500-Watt.html?listtype=search&searchparam=power supply

10 minutes ago, Alien 13 said:

 

As to expensive hobbies try HiFi, you can pay more for a cable than the cost of a TAK for example.

Alan

Anyone fancy a AV Designhaus Derenville VPM tirntable. 🙂

Costs way more than the average house in the UK. 🙀🙀🙀

8 minutes ago, cajen2 said:

And don't even get me started on marine reefkeeping, where even a modest 90cm tank plus equipment runs into several thousand....each fish or coral that you buy is £50-£100+ ..... and the electricity / maintenance costs a fortune too.

I’ve often admired them but wanting to eat and keep a roof over my head means NOOOOOOO😫

Yes for your 90 / 500 refractor keeping the finder relatively small is a good idea.

The Rigel Quikfinder is popular and very compact finder. A good alternative to the Telrad.

https://www.firstlightoptics.com/finders/rigel-quikfinder-compact-reflex-sight.html

Or the 6x30 RACI finder if you prefer an optical finder.

https://www.firstlightoptics.com/finders/sky-watcher-6x30-right-angled-finderscope.html

Same here. The updated interface is much improved and getting closer to the finished article. Test alignments in the conservatory went well. 👍🏻

Slewing is so quiet. Will measure the quietness with my decibel meter later.

I bought a set of standard coloured filter ages ago. Been sitting in a drawer unused for ages as well. I quickly found specialist filters were more useful. 

Some need a moon filter and some don’t. All depends on how your eyes handle bright light. The variable polarising filter is very useful though as you can dim to the right level and comes in handy for other bright subjects such as Venus.

Get a Concentre. The perfect tool for getting your secondary set up perfectly. I now consider it an essential for setting up a newt (dob) as I’ve found once you've got the secondary right the primary will only need minor tweeks.

After the Concentre then I use the laser.to adjust the primary. I use the Hotech laser which is propely collimated to start with. There are good lasers and cheap lasers but no good cheap lasers.

https://www.firstlightoptics.com/other-collimation-tools/ts-concenter-2-adjustment-eyepiece-for-newtonian-telescopes.html

Two great lunar reference books and not too expensive. 1068 pages worth. So much more user friendly than Luna Cognita. 👍🏻

From one of my reference books.

The Meade HD60s are in stock at The place I linked to.