Upgrading from 6" to 8" OTA

[PeteF]

I have a 6" Celestron Evolution 6"which I bought as my first telescope. I didn't want to commit to anything more expensive when I bought it until I could prove it wouldn't become a coat hanger in the corner of the room.

I've been really happy with it, and can observe far more than I imagined from my city location. With 9 months use or so I've therefore been considering upgrading the OTA to a C8 XLT, which I was led to believe would be a straight forward swap, both the 6 and 8" versions using the same GoTo.

I wondered if there would be a noticeable improvement between the two different OTA sizes? I'm not really quite sure what to expect and it's still quite a significant purchase.

[Camelopardalis]

Pete, the 8” packs a fair bit more mirror area over the 6” so there is an appreciable difference between the two...not night and day, but it is noticeable. However, the gains may well be swamped out by the light pollution in the city.

Many revisions of the C8 optical tube will slip straight into the dovetail clamp on your Evolution, so you might save a few $$$ by looking out for a good quality used one.

Cheapest thing I’d suggest is to take your scope out to one of the club gatherings outside of the city. You’ll get more out of any scope that way.

[PeteF]

Thanks for that. Yes I used to live in central Australia so I've been spoiled when younger.

While we get away with the telescope when we can, the reality is I take it out, it's super-quick to setup and even if I only spend an hour or so looking at something specific I wanted to see, that's an hour well spent. I've been quite surprised at how well I'm able to see, admittedly we're in a valley and while that limits the horizon significantly to views away from the city, I think it has upsides.

I hope to slowly build up quality eyepieces and upgrade my telescope as experience and finances allow. I like to see the progression in what I do. I think I will start another thread on eyepieces and keep it seperate to this one, to allow others to find it should they be interested in the same path in future. So far I've only bought one Tele Vue 2x Barlow, which sadly I never use. I find the two standard eyepieces (Celestron 13 and 40 mm Plossl) are unremarkably a good match for the OTA and the 13 mm + 2x is too much for that telescope.

My understanding is an C8 OTA is a good compromise for telescopes of this type; small enough to be able to take it out/around easily, but big enough to gather light. It would be very interesting to compare them side by side.

[Camelopardalis]

Yeah a lot of folk will pooh-pooh the idea, but a C8 on a simple goto mount (I have the Nexstar 8SE) is a convenient scope to get going with IMO.

Just set your expectations that it's not going to open up whole new field of visual astronomy from the city ;)