dweller25

Hello Charles I am also a spectacle wearer and observe with them on as I like to draw at the eyepiece. I look for eyepiece with a long eye relief, typically around 20mm eye relief is good for me. Roughly, roughly Longer focal length eyepieces like your 20,35 and 32mm will have lots of eye relief, the 15mm and below is where you may struggle ? One solution is to take your specs off but I prefer to leave them on and then Barlow the longer focal length eyepieces, so with a x2 Barlow your 20mm eyepiece would become a 10mm but still have long eye relief 🙂 You have a good scope, for the planets you need a magnification of around x180 which is a 4mm eyepiece or an 8mm eyepiece with a x2 Barlow. The eyepiece magnification formula is : magnification = focal length of telescope/focal length of eyepiece. Your scope has a focal length of 750mm, so magnification for a 4mm eyepiece = 750/4, which is x187 Apologies if you know all this 👍

@SwiMatt I see you are using your Skymax 127 on a light weight alt-az setup. Is this because you need to travel to an observing site and need a small light setup ?

Hello @SwiMatt One factor that can drastically effect planetary views is thermal equilibrium of the primary mirror. It can take a long time for the thin boundary layer of residual heat to disappear from the surface of the primary. To overcome this you could try putting a couple of layers of reflectix around the OTA. This will effectively lag the scope preventing the temperature gradient between the optics and the cooler OTA walls. This will allow you to use scope immediately when you take it out and will prevent dew formation on the corrector for much longer.

And the Vixen 115mm at 4.4Kg https://www.harrisontelescopes.co.uk/acatalog/vixen-sd115-.html

And here is a 120mm doublet Fluorite from Agema https://www.agemaoptics.com/telescopes/agema-sd-120/

The Askar 120 triplet OTA is 5.7Kg Including tube rings and dovetail it’s 6.5Kg https://www.firstlightoptics.com/askar-telescopes/askar-120-apo-triplet-refractor.html

Sorry, No, I am visual only

Hello @Hellfire and welcome to SGL. You have a great scope - try to get it on Jupiter ASAP as it’s past closest approach now. What eyepieces do you have ?

I had an OK C6, an excellent C8 and a bad C9.25, in my opinion optical quality does vary with SCT’s. I now have a Mewlon 180 which is superb, it’s very sharp and it’s high contrast continues to amaze me compared to the SCT’s.

Sadly my C9.25 was a lemon, easily beaten by a 4” refractor

@Flame Nebula I know you only asked about the C9.25 but for similar money you can get one of these which will be much more useable on more nights. Cools quicker and does not need collimating too… https://www.firstlightoptics.com/askar-telescopes/askar-140-apo-triplet-refractor.html

The C9.25 can be a very good scope, it will need at least an EQ6 to support it. Thermal stability issues can be avoided by wrapping the OTA with Reflectix.

That fall could will get expensive 😱

Yes, as others have said, you have already reached the maximum useful limit at x170. So your next eyepiece should have a 4” refractor attached to it 🙂👍

Good decision 👍

He’s dead

Welcome to SGL, this is a UK based site but see the post made by bosun21 above 👍

Excellent image 👍

They are not magic enough to overcome big high quality mirrors 👍 Lights touch paper and steps back 🤣

OK for planetary though ??

This may fit, but check with FLO first…. https://www.firstlightoptics.com/sky-watcher-mount-accessories/sky-watcher-stainless-steel-175-tripod-for-heq5-eq5.html

Where do you live ?

Just mulling things over @vlaiv on a cloudy day/week/month. But thanks for the considerations 👍

Well the Newt seems to be winning, but those refractors do look good…..

I tend to match my scope aperture to the average seeing conditions where I live which is around 1 arc second. So I have a 120mm refractor with a resolution of 0.96 arc seconds. But I do mostly planetary viewing. IF I did DSO I would buy a light 10” Newtonian for the light grasp.