Chris

You're absolutely right John, I once had a Synta 102 f10 with bad SA and you just couldn't get a sharp image. This is a worry at this price point and focal ratio, I just hope I'm lucky enough to get a good one. If not there probably isn't much I can do to correct it. CA is something I can control to some extent hence the thread, but I should should probably check that the SA is reasonably controlled first. If I remember rightly you just check for any difference between the fresnel rings in and outside focus, but is there any thing specific to look out for?

I hope so, it would be a shame to have my hands on a short achro and not give it a go. I'll look out for these filters second hand and start experimenting with them as and when I find them. Might be a little while as I've just started working on two video series- An up cycle obsy build series, and a £200 to £2k telescope series, starting with my choice of astrographs. My channel is here if you want to keep an eye out? https://www.youtube.com/channel/UCBTXZYuFWQ6lx51L4GeY0Lw?view_as=subscriber I'll keep my eyes peeled for your review! but no pressure

A very useful chart John. I remember I used to have this on my drive somewhere. Thanks for the reminder

I would be interested in reading your thoughts. No rush

A bit of everything which is why I'm after something which will improve the CA without making the view too un natural. It's not the ideal scope for a do it all scope I know, but needed something I can use as part of the obsy setup once built and big scope installed. The ST102 can be piggybacked as a super finder guide scope.

Ah very interesting, maybe this is more of a subjective rather than a quantitative thing then. Maybe I should try and do my own shoot out then! I'll add this test to my list of youtube video ideas. Thanks

Thanks John, it's interesting that the 102 f5 should show similar levels of CA as the 150 f8 as the later is a scope I've always been curious about and intended to try at some point. I've used the ST120 before and thought the CA was a little too much without intervention so I'm looking forward to playing with the 102.

Cool thanks, I've owned a number of achro's but never a ST102 so I was trying to gauge the CA. In summary then, an aperture mask is probably a better bet than any of the minus violet filters, Cheers I guess I could stop it down to 80mm f/6.25 thus still keeping some image brightness.

Hi all, I've ordered this short achromat as a grab n go, and I'm looking for filter advice please. https://www.firstlightoptics.com/sky-watcher-starquest/sky-watcher-starquest-102r-f49-achromatic-refractor-telescope.html Alas I can't afford the dream 4" Apo and an obsy build, so I was wondering which is the best filter I can use to try and undo some of the chromatic aberration without making the view appear too 'funky' and unnatural? Looking at the good old FLO site there's a number of Baader filters which all seem to be variations on a minus violet filter. Which one would people recommend? https://www.firstlightoptics.com/achromat-semi-apo-filters.html Or any other? Thanks

I think the comment section would light up for that subject, go for it! It would defo get the views. Although, aren't dark matter and energy just labels to explain our observations e.g. why do galaxies hold together when spinning so quickly when the centripetal force should outweigh gravity? Would you be suggesting that it may not be either matter or energy? Anyway, I would like to see your video on that, you've absolutely next levelled all the vids I've watched so far! I guess you've learnt a lot working in the television industry.

The only thing I can add to the above comments is that a dew shield is a must for SCT's and Maks, but on the plus side you can wave good bye to diffraction spikes on planets and stars!

That's a lovely looking scope Stu. I didn't know you had this one. New purchase?

Beautifully processed image, nice one!

Indeed! If you're mainly interested in the Moon, planets, and the odd double star and glob visually, it could be all you need!

They 're expensive but blooming compact, light and versatile for their aperture. small Maks are cool too for grab n go Lunar and planetary, but I could never have a small Mak as an only scope, whereas I could cope with a C8 as an only scope. Or even a C6 if I had enough little goodies to get the most out of it! The problem is you can get a semi decent 4" f7 ED frac for C8 money and that I'd take over a C8. As for price, I have a totally new respect for optics since 'trying' to grind my own mirror. Shelved at the moment, but I've put enough money and time into that little franchise to realise how spoilt we are with today's prices for optics. SCT's are only relatively expensive but at the same time cheap!

Nice one Mick, I can't see any clipping but wondering if there might be a slight red cast? Anyway, it's a cool PN either way.

I think you might be the first man to virtually land on the Moon using an Earth based telescope!

This video was also fun

What brilliant production values and humour! This guys brilliant, I'm off to subscribe to his channel.

I didn't know a Venus image like this was possible for an amateur! really exceptional, well done!

I could be wrong but I think small aperture telescopes produce larger airy disks around stars (larger stars!)

I'm guessing it got put on hold for the winter? but hope he got the outside clad at least.

I see that the 10" version is available for 1-2 day delivery as well just to rub it in.

That Rainbow mount looks fantastic! At the IAS2019 I saw one throwing an Esprit 120 around like it wasn't there, and the mount didn't even have a counter weight on!

You're not selling this design to me Dave lol