Spile

I can recommend an 8” manual Dobsonian for a number of reasons and I chose mine some years ago because…

• I was interested in visual astronomy. I wanted to observe in real-time.
• I wanted the largest proportion of my budget to be spent on the mirror and focuser so that I got great, pleasing views with no colour distortion.
• I wanted a mount that was secure and stable so I didn’t get shaky views.
• I wanted a telescope that would be capable of viewing solar system objects, binary stars and where possible, Dark Sky Objects.
• I needed a telescope that I could point and observe and was quick to set up. I didn’t want to spend time aligning a polar or computerised mount. 
• I wanted a telescope that I could upgrade.

I have the Skywatcher 200P but it has cost me money to upgrade it to the specification as the GSO equivalent so that is what I would recommend you get.

4 minutes ago, Elp said:

I don't think you even need all that. All I used was a collimation cap when I had my 130pds.

Yes I can get close with just a cap. However…

The cross hairs mean it’s easier with the Cheshire eyepiece and the long sight tube makes it easier to confirm the outer edge of the secondary is concentric. 

Sort out the offset errors (if there are any) first and then correct the tilt/rotation error. All done with your Cheshire eyepiece and sight tube combination tool.

I’d be asking the question why do you need to upgrade/spend money. What are you trying to achieve?

I would go for the Bresser mainly due to the solid tube and Crayford focuser. 

I can recommend adapting it for a dual dovetail…

Did you check out M105 and NGC 3384 whilst you were around M98 and M99? I checked them out last night in moderately light polluted skies.

I was there until 11 o’clock and met some members of Bromsgrove ARS and accidentally @michaelmorris

I use the fingertip and distilled water method as per my blog to clean my mirror every 18 months or so when the dust has built up to a degree that I am uncomfortable with.

Another vote for the Baader Hyperion IV. I combine mine with a 30mm ultra wide when I need a bigger field of view but it’s not an issue for me in reality.

If I had to collimate my reflector at a particular angle I would be worried. 

I’ve created a list of 500 double stars rated on a five point scale that you may find useful.

This is what I get from your earlier image. I couldn't see the edge of the sight tube in the last image so you might want to take a picture through a cap. Nevertheless the secondary looks good.

Ignore the clips until steps 1 and 2 have been completed so a=b=c=d and e=f

and the cross hairs of the Cheshire eyepiece and sight tube and and the dark offset secondary reflection (x2) is offset toward the primary mirror.

11 hours ago, Xilman said:

While we're on the CN-bashing wagon: one of the things that drive me away from there for months at a time is the attitude and actions of some of the CN moderators. They appear to be jobs-worth sticklers for the letter of the rules with no imagination or flexibility. Some mods are good people and I know that they are also dismayed by the actions of some of their colleagues.

What is very different about SGL is that the mods are almost always invisible, except when asked for assistance --- when help is usually prompt and plentiful.

That has definitely not been my experience of CN ; the moderators there have never had an issue with my posts apart from kindly letting me know they had moved one to a different sub forum. The forum software on SGL is definitely better designed in my opinion.

As you can see I am also a zoom fan. I went for the Baader but user reviews of the Svbony equivalent are excellent so I would go for that.

Congratulations. A fantastic reference.

Whenever I need to check or confirm details of a double star I always refer to Stelle Doppie

https://www.stelledoppie.it/

I would recommend checking the alignment of a primary mirror with a cap.

One thing to bear in mind is that as well as using a star you will need to use high magnification.   I centre (this is important) Polaris in the eyepiece using high (200X) power. I move the focuser slightly in and then out and compare both views. The out of focus views show unbroken, concentric rings.

Personally I would not be without a zoom eyepiece.

I couldn’t use a RACI without a straight through non magnifying finder. 

1 hour ago, cajen2 said:

It was fine as far as it went but all such finders seem to suffer a lack of stability, with two thumbscrews and a fixed one. 

Spring loaded rather than fixed surely?

For the secondary mirror use and trust the Cheshire eyepiece and sight tube combination tool. Keep the cap for alignment of the primary.