dweller25

No mirrors ??? That’s a shame

Jupiter and Saturn are both well past closest approach and very low too, so you will not get great views now But your scope is more capable than what you are seeing - as said above the scope may need collimating And it needs more time than your refactor to cool

Well done

Wonderful video and writeup, thanks for sharing

My favourite scope type is a refractor

I like Orthos but started to find the eye-relief on the 12.5mm too tight so changed to a Pentax XF 12mm. Really like the comfort and they are just as sharp on the planets as the Orthos

Hello Paul, It sounds like you have a similar issue to me - I generally struggle with "poor seeing" - now this can be a number of factors :- 1. The Jetstream - nothing you can do about that except wait for another night. 2. Scope not cooled - best way to cool your Mak is take off the front and rear caps and point the OTA towards the ground to allow any warm air to escape OR insulate the OTA so cool down is not an issue at all. 3. Thermals from the concrete ground or buildings in the direction you are looking - if you observe on concrete spray it with water to cool it down - better still change to a grass location and away from looking over buildings. The 100ED refractor will be very close to the 150mm Mak for planetary and lunar views and will thermally stabilise faster, giving sharper images and will be good for solar too, so it's probably a more suitable scope for you. Personally I would avoid the 120mm Achromat as it will have chromatic Aberration. At the moment the planets are very low - at least in the UK - not sure where you are?? - so that will always compromise the quality of views. Good luck

Have you tried insulating the Mak with a couple of layers of Reflectix ?? You may be pleasantly surprised.....

Actually - YES - I have a Baader prism that will accept this - thanks for the idea

Thanks for the excellent feedback John.

My TSA102 despite numerous attempts to tune the focuser annoyingly still has a little image shift when trying to get fine focus on the planets at high magnifications and is quite stiff ( the best option for the least image shift !) Putting a Feathertouch on would sort it out but they are very expensive so I am thinking about putting this Borg helical focuser on the back of the scope for fine focus....... https://www.firstlightoptics.com/borg-helical/borg-helical-focuser-s-7315.html I am wondering if anyone else has tried this and if so how did it work out ??

Fantastic, thanks for sharing

As mentioned above , if nudging a Dob consider Vixen SLV’s

Sorry - That’s not an option

It's easier to nudge an EQ - once on target you only need to move the RA - and you can use a slo-mo cable for that.