DevonSkies

Thanks for all the comments in this thread. I think from what I've heard I can conclude that, although the Mak is a good little scope, the 100ED is worth the extra for the best planetary views. I think, deep down, I knew this all along. If I'm lucky I might find a used 100ED near me; otherwise I'll scrape together the cash for a new one. I don't want to plump for the mak and then wish I'd got the ED all along.

I already have a 250 Dob, so I don't really want another dob cluttering up the garage!

Plenty of food for thought. I've also been considering the Altair 102mm f/11 achromat as an other option. It's a lot cheaper than the 100ED, but obviously will exhibit a certain amount of CA on bright targets. Whether the CA would be bad enough to justify spending the extra on ED glass is not clear to me. The longer tube of the f11 scope also makes mounting more of a problem.

Thanks for that - I hear what you're saying about contrast. I agree the ED100 is great value for an ED refractor.

I can keep it in an unheated garage. It's still a bit warmer than outside this time of year though. My 10" Dob takes at least an hour to cool, maybe two hours before the star test really settles down.

Thanks, that's really useful information. It's a tough choice. I can afford the Mak 127 right now, but I'd have to save a bit longer to buy the 100ED. I've also got a feeling I would eventually need to upgrade my mount for the 100ED, as the Porta II suffers from the wobbles at high magnifications, which will only get worse with a longer tube. On the other hand, cool-down is a concern with the Mak, as I tend to have limited opportunities to observe, except on those rare clear, still nights.

Aside from the goto issue, do you find the mount tracks well enough when it's aligned with the target?

Thanks for that. The Mak appeals both for the price and because it should behave better on my Porta II mount than an f/9 refractor. I have some decent EPs already, so that shouldn't be a problem. Does it take a 'normal' (i.e. push fit) 1.25" diagonal?

Yes, I saw that one. Local collection only though, and Cambridgeshire is too far for me!

Thanks, it's good to hear from someone who has had both. In what ways was the 100ED better specifically? And do you feel it was £300 better?

I'm still on the lookout for a relatively lightweight scope for lunar, planetary and double star observations. I have a 10" Dob which will obviously wipe the floor with most small scopes, but I often can't be bothered with lugging it out to the garden for a quick look at the moon or Jupiter. It sounds like the SW Evostar 100ED would be a nice scope for this purpose. But at over £600 for the OTA it would be a major investment for me. So, I wonder whether the Skymax 127 Maksutov would be a worthy alternative, given the much lower cost (around £350 including a goto mount). I understand the Mak will have a narrower field of view, but that's OK as I already have an ST102 for wide field. What I'm looking for is nice sharp, contrasty views of planets and the moon, as well as good performance on double stars. Any thoughts? How different will the view be between these two scopes? Thanks, Ed

Yes, the Starwave 102 f11 does look like a good alternative (maybe even better). I notice Astroboot have a TAL 125 Apo in their Bargain Zone at the moment - out of my price range though! Optical Vision (the importers) still list the 125 on their website, but maybe they are just clearing out remaining stock.

I contacted a couple of dealers today (Rother Valley Optics and Harrison Telescopes) who recently listed the TAL 100RS on their websites. Both told me that the TAL is no longer being imported! Sounds like bad news for anyone looking for one of these highly-regarded achromats. Guess I'll have to save my pennies for a SW 100ED instead.

Thanks, that's good info. I have this padded bag for my ST102: http://www.rothervalleyoptics.co.uk/geoptik-padded-case-for-100mm-refractors-f750.html and it's actually oversized for the scope - in fact I'm sure an ST120 would fit. I'm wondering if I'm taking that bag on holiday anyway, I might as well fill it up and put an ST120 in it!

Looks good. How do you find the size/weight compared to the ST102? Does it still make a good grab-and-go?