Opinions on Upgrading My Refractor

[kz1bob]

Hi All,

I am looking to upgrade my refractor. The final candidates have come down to The Altair-Astro Starwave 102ED or the Wave Series 80mm Triplet. Both have FPL-53 glass, the 102 is a doublet and the 80 is a triplet. My question and discussion point is whether the 102mm doublet with its greater light collecting ability would be more desirable than the 80mm with its triplet APO configuration.

My intent is to get better at AP but I do like just looking sometimes. Price-wise they are about £100 apart so not a lot in it.

Any finer points from the veterans in the group would be very much appreciated. Thanks in advance for all feedback.

[rickwayne]

Upgrade from what, may I ask? And what are your criteria for getting better? Smaller rounder stars in your DSO work? I'm assuming that you're after that, and not planets, if you're looking at these scopes.

Hardly a "veteran", but I do read a fair bit, does that count? The difference in resolving power is unlikely to matter unless you live someplace where terrific seeing is common -- we're more often limited by atmospheric effects than optical ones. Light-gathering power is attractive, but you can just take more subs, or go for longer exposures, so the main advantage of the 102mm scope is that you get slightly more sleep. ? Chromatic aberration is IMHO much harder to deal with, but now I'm WELL beyond the boundaries of my own experience so I will let the vets chime in on that one.

[kz1bob]

I had a Bresser AR102s/600. It was fine for looking at things but all my photo attempts were very poor (accepting my skill level as part of the challenge). CA was a big issue and even looking at the sun and moon the images were not very well defined. I used a semi-APO filter but didn't see a lot of difference to be honest.

Like you, I do a lot of reading (I have the 'bible' so often recommended here) but find I am almost in information overload trying to keep everything straight in my head. I do live in a fairly light polluted area but can 'see' the Orion Nebulae though not in great detail. I am hoping that better glass, reducing CA, and proper filtering to help with the light pollution will make for more rewarding outings.

I am leaning towards the 80mm as it is smaller and lighter and from the things I have seen from other people, it is more than capable of producing results I would like to achieve. Also, being an APO triplet, should be better when dealing with CA.

Thanks for your input. I have a day trip planned to go speak to an actual astronomy shop this weekend so hopefully I will have a well informed purchase.

[happy-kat]

Whilst talking of CA from the cheaper perspective I've found StarTools quite good at removing it.

Enjoy your window shopping trip.

[astrosathya]

I use a 15 year old Orion 80ED doublet telescope. It has only a single ED element. I've used it both with my Mono CCD as well as my DSLR. No discernable CA. Therefore, I'd probably say that you could go for the 100mm doublet ED scope to get a better resolution than the 80mm Triplet. Also, there's nothing that software cannot do these days. Go for the 100 doublet with a field flattener. 

[kz1bob]

Thank you all for your comments, they were very helpful.

Made my trip to Tring Astro to have a chat and I must say, Neil was amazingly helpful. He was very patient with my naïve questions and fully answered them. I posed my question re: the 80mm APO v the 102mm doublet. He gave me a quick lesson on the pros and cons of each and asked for more detail about what I was looking to do. He then said, not sure if you would be interested, but I just took in as part exchange an Altair Astro Wave 102mm APO! Result! This was my 'dream' scope but just beyond my price range, however his second hand one was priced perfectly!

I got it home and set it up on the mount. The build quality of this scope is brilliant. It is rock solid in the mount and there is no flex when adjusting the guide scope. Sadly, normal weather has returned to the UK and it is currently raining, so haven't had a chance to point it at anything yet. 

If you like to actually look and feel astro equipment and are reasonably close (my drive was about 1.5 hours each way), I cannot recommend enough the folks at Tring Astro.

[PaulB]

 I can't fault Altair Astro and their high-quality Refractors. In my view, they are as good as Tak's and other premium fracs that cost double the money.

I own a AA-SW 115 EDT. I use this for CCD imaging but also visual too. Mine was an ex-demo that I brought from Altair at Kelling in 2016. I couldn't believe my luck when it was offered at a silly price.

It's your fault for the change in the weather.

But when the rains and cloud go. I am sure you will be delighted with you're purchase. You must sign up for the user group.