John

A good decision I think. An undermounted scope is very frustrating.

Length has more impact than weight mostly but there are exceptions when the optical tube weight is close to the mount limit. With the weight of your scope I don't think it's possible to say with any certainty whether or not the star discovery mount would be able to handle it For low to medium magnifications it might do OK but become less easy to use with higher powers.

I'm glad that I managed to get a glimpse of the last one ! Still got my fingers crossed for Monday though.

Personally I would go for either a Telrad or a Rigel Quikfinder to use alongside the supplied optical finder and then think about upgrading the optical finder to a righ angle correct image one in due course. I use the word "Personally" here because I feel that finders are a personal preference thing. Over the years I've found having a right angle optical finder alongside a Rigel / Telrad works best for me with my dob. Others will find different approaches work best for them. No right or wrong answer really other than that you do need a finder of some sort on the scope !. Maybe the suggestion of going with what comes as stock with the scope then seeing how your preferences develop is the most sensible option ?

I've assumed that Anthony1979 is talking about the F/5 150P optical tube. I agree that the F/8 tube as used in the Skywatcher Skyliner 150P dob would not be suitable on the mount.

In terms of optical performance I don't think the Bresser would be better than the Skywatcher and £110 can be a lot of cash if you are starting out. One of the joys of dobs is that they can be modded over time to improve how they work but the Skywatcher 200P dob is very useable straight from the box in my view.

Skywatcher sell that mount with an F/5 150mm newtonian on it so I'm sure it would be OK for visual observing at least. Not for imaging though.

I expect the Earl of Rosse had a servant or two at the bottom end of the scope to tilt the primary while he was observing a star. Adjusting the secondary must have been risky though !

If it is going to be used for deep sky photography, an 8 inch newtonian needs a more stable mount than the EQ5. At least an HEQ5 and preferrably an EQ6. For a strong start to visual observing I think your shopping list is fine. I would get a Telrad if you can - it will make finding things easier than just using the stock 50mm optical finder. I've lost count of the number of happy owners of the Skywatcher 200P dobsonian that we have on this forum. I was one not so long ago and found the scope excellent

The Tele Vue Apollo 11 is not the only commemorative piece of kit celebrating the lunar missions though. Hasselblad have one and for just under £7,000 you can have one too

As I said earlier in this thread, I've found that my simple cheshire eyepiece delivers results that check out when the scope is star tested (the acid test for me) so thats what I stick with now.

Sorry I missed this comment. I was specifically asked to replace the worm bearings on both axes by Rowan Astronomy and followed their instructions when I did so. Otherwise I am resisting the temptation to tweak and adjust the mount. I don't want any of my ham fisted efforts to impact the performance one way or another ! While on the subject of performance, poor weather conditions have meant that I've simply not been able to get out and observe at all with the AZ100 over the past couple of weeks. In fact a quick dash out with binoculars is all that I've been able to do astronomy-wise generally Just one good clear session of 2-3 hours would be great - I'm crossing my fingers and toes !

When you check that the laser collimator is itself collimated, 10m is a good distance and the laser unit needs to be rotated just around it's long axis with no other motion. A simple "V block" can help with this. Something like this will do the job: https://www.thingiverse.com/make:334814 Assuming that the laser is now collimated accurately itself, if the laser spot is missing the central mark on the primary this means that the tilt of the secondary mirror needs to be adjusted. Once you have done that and the laser spot is right in the centre of the primary mirror, you then move on to see if the returning laser is striking the centre of the 90 degree target built into the laser collimator. If it is not then primary tilt adjustments are needed to get it central. It's important to do the secondary tilt first followed by the primary tilt. Then star test when you get a clear night. Edit: trying to get different collimating tools to agree with each other can be a thankless task !. I tend to stick with the method that results in an accurate star test and stay with that. For me that has been a cheshire eyepiece but a laser collimator can do a good job if properly collimated and if the correct order of steps is followed.

For the last transit we had solid cloud but I popped a scope out just in case and it did clear for just a few minutes so that at least I can say that I saw Mercury crossing the Sun. If I get any views around 1st and 2nd contact plus something when the planet is crossing the disk, I'll be pleased. Certainly not expecting long clear spells !

Maybe your dust is more stubborn than mine ?

I find the hand held "hurricane blower" is very effective. I would not use anything that involves propellant in case anything other than air finds it's way onto the optical surface. My hand held and operated blower provides a lot of air force up to a few cm from the nozzle and keeps every thing portable and simple. I've used this for years on refractor objectives, mirrors and eyepieces and it's 100% safe and successful.

I reckon one of the main points of a product like this is that it gets people talking about the company. There is this thread here and a couple of long and active ones on Cloudynights and I expect similar threads running on Ice in Space and other forums around the world. The profits on the sale of the 300 units (thanks for the correction ) will be relatively "small beer" I suspect.

I think they could have charged more and still sold them. For some that sort of money is more or less loose change. A couple of new tyres on a Lamborghini or a Ferrari for example.

Hello and welcome to the forum ! That looks similar to my situation at home. If you pick your targets and plan your sessions (use Cartes du Ciel or Stellarium) and wait for targets to get well above the horizon and into the more stable areas of seeing and / or lower light pollution you can still have a lot of fun. With the major planets so low currently I've found scopes on taller tripods (ie: refractors) easier to use because it's simply easier to point such scopes at low lying targets and refractors seem to cut through the poor seeing closer to the horizon better. For most other targets my 12 inch dob has done a great job as usual, despite the compromises of my observing location. I've always kept my scopes to a size which can be moved around fairly easily during a session to make the best of the views that I do have.

Nothing is ever 10x as good as anything else IMHO. Take a Skywatcher 102mm F/9.8 achro refractor and a Tak FC-100DL - 10x the price difference easily but is the Tak 10x better (whatever that might mean) ?. Zeiss ZAO 10mm orthos go for around £400 or more each these days on the used market. Are they 10x better than a Baader Classic 10mm ?. I sincerely doubt it. The Apollo 11 will sell because it's a limited edition and is thought to be iconic of a very well respected family company and of Al Nagler who did have a role in the Apollo programme. Many won't come out of their packaging much I suspect. The market for them will be very limited worldwide but there are only 500 eyepieces so supply will probably match demand in the end.

I'm sure they will sell well despite the price I'll be very happy to try one out if FLO would like me to

That mirror looks in good condition to me. Obviously it's optical accuracy cannot be determined until it is used. Many folks like a central spot / ring in the centre of their mirror to aid collimatiobn but that can be added later.

Yet another cloudy night here ......

You will need to budget for a suitable secondary as well then. The size of secondary you need will depend on the focal ratio of the primary mirror. You will notice if the coatings are in need of replacement. Holding the mirror up to the sky and viewing from behind it will reveal if the coatings have holes etc in them. Ideally there should be no light coming though the mirror although one or two pin hooles are OK. The top surface should look evenly bright with no flaking, odd patchas, stains etc. Often coatings start to deteriorate from the outer edges first so those are worth examining. Can the seller post you some photos of the mirror ? - you could post them on here then.

For a commercial mirror (Skywatcher, GSO, Meade, Orion Optics etc) assuming that it and it's coatings are in reasonable condition and that it has no scratches / damage, that would be a very good price. If it needs re-coating before it can be used that will add as much £100 to the cost. For a DIY mirror of undefined quality that would be about the going rate. Does that include the seconady mirror ?. They are often sold as a set.