RobertI

Interesting, I’ll do some proper tweaking and testing to see what I can do, it would be great to find out I can get pinpoint stars with the scope, although I think mirror flop may end up spoiling the party.

I’m not an expert on doubles by any means, but have observed a few tricky doubles of this type, with the secondary on the diffraction ring. In general I have found that really high mags will eventually reveal the secondary clearly in the diffraction ring if the conditions are right, but these higher mags are trickier to reach in my small scopes, or become too dim. I guess my results have fallen into one of the following main categories, which are still pretty subjective and probably not very useful to anyone! 😆 Not seen Suspected brightening - glimpses of slight brightening of the diffraction ring in the correct position position angle Definite brightening - obvious brightening at the correct position angle Resolved - the secondary clearly stands out as a star in the diffraction ring To address the original question, I guess in this situation where the secondary is on the diffraction ring, and there is a clear gap, the term “split” isn’t really useful anymore and the above descriptions might be more useful?

Interesting post, I’ll take your word for the logic of your analysis! I think ‘mushiness’ is too vague a term to really understand what problems people are seeing. It seems like there are many problems. My personal experience with my C8 is that bright stars are not always pinpoint and can seem a bit ‘hairy’ (I think @michael.h.f.wilkinson coined this term - I like it!). This makes certain doubles with bright primaries difficult to split and it means I tend to avoid using the scope for double splitting, probably unreasonably so. I think part of the problem is that SCTs have such long focal lengths you can often forget how high a power you are observing. I’ve also found that low contrast planetary features are not as distinct as you would hope from the aperture. But I’ve never really noticed any kind of ‘mush’ types issues on the moon or clusters. Galaxies and nebulae are mushy anyway! 🙂

Superb observing report and great read. Your carefully selected images really bring to life the experience of observing with a large scope. M13 is amazing through an 8" so it must be stunning in an 18". This is an interesting contrast to my recent observation of M13 using my 4" frac, where I could resolve a reasonable number of stars at x200, but the view was very dim and not really possible to go any higher - not really the right size scope for viewing these wonderful globs! BTW it would be useful if you added the scope details at the start of the report (I know it's on your website version). Keep them coming.

The Heritage 130P, being so light, works really well on the mini giro. It’s a lot of light gathering for such ultra-potable setup. I wouldn’t use the mini-giro for anything bigger though, although plenty of folk have. Yes, I tried to track down a cheap 130P OTA myself so I could ‘pimp’ it in the same way, but I never managed to find one. True, but the 130PDS has a bigger secondary for imaging, so you probably got better views with your 130P!

Agreed, I have had a lot of success with my Heritage 130P, usually mounted on my Mini Giro WR. It’s good for deep sky (memorable views of the Veil from a dark site), excellent doubles splitter and useful on the moon. Never really tried it with the planets but I’m confident it would acquit itself well. In fact I like the 5” Newt format so much I have considered a 130PDS - shame they don’t do a 130P specifically for visual.

Looks like it’s designed to slice through atmosphere like a hypodermic syringe (I think that’s a mixed metaphor!) 🙂

When I was a teenager into astronomy in the early 80’s, I had a Fullerscopes 6” Newtonian. But what I really wanted was a Celestron SCT. Back then the Celestron brand was considered upmarket and SCTs were aspirational scopes - at least that’s how I remember I perceived things as a teenager. So naturally when I resurrected my interest in the late 90’s I bought the scope I had always wanted - a Celestron C8 (marketed as the G8 with the non-goto CG5 mount). It has been a really good all round scope over the years, well used and twenty odd years later it is still in good condition as it’s built like a tank and has an enclosed mirror. Other scopes in my arsenal, particularly the 102ED have shown me it’s optical shortcomings in certain areas, especially doubles, but for globulars and faint fuzzies it’s still the best scope in my arsenal, and it’s no slouch on planets and luna on nights of good seeing. Mirror shift is awful and mirror flop means the collimation varies slightly as you move it around the sky but I’d never say it moves out of collimation enough to make an observable difference. But it is very portable and easy to set up. Overall a very easy scope to live with.

I always enjoy reading your posts, so thank YOU!

Amazing! We astronomers live for those special moments don’t we? Sounds like Zeta Hercules was the perfect test for the 4” - truly memorable by the sound of it. 🙂 Checking back on my observing log, I have also struggled to see this with my 4” refractor with nothing more than a suspected brightening of the diffraction ring. With my 150 Newt I had more success, getting a clear view of the secondary, but it took excellent seeing and a magnification of 540x to achieve it! I will persevere with the refractor….

That’s the best one yet! 😂😂 Although to be fair the finder is pointing in the right direction even if the rest of the scope is not! I think this “top of the line” scope (see description) is wasted on them.

….. and then you woke up. 😁 Seriously, certainly sounds like you witnessed the Starlink deployment and you describe it perfectly. It’s lucky we have such a wealth of knowledge here on SGL, this would be fodder for a panic over an alien invasion anywhere else!

Nice comparison, although admittedly on premium scopes. So basically (spoiler alert) the 5” apo refractor and the 7” premium Newtonian gave similar performance overall, beating the Intes 6” compound scope. Kind of backs up the traditional wisdom about 4” fracs and 6” Newts being similar performance. But the article also makes the point that you can enjoy whatever scope you happen to possess!

I’m sure this question will generate a lot of answers! My understanding is that unobstructed aperture of the refractor allows for greater contrast and cleaner images which can make up for its lack of aperture and potentially provide better views certain objects such as planets. I would have thought greater resolution of a 6” Newtonian will always give better views of objects such as globular clusters and should reveal fainter DSOs. So as a very general statement it is probably true but depends a lot on what you enjoy looking at.

Just to add another perspective to this thread (and hopefully not confuse the the OP!) it is possible to do basic astrophotography with a lightweight altaz mount. Below is a recent EEVA (Electronically Enhanced Visual Astronomy) session with my 66mm refractor on a SkyProdigy mount - very similar to the AZ-GTI or Virtuoso class mount I would think in terms of accuracy and load capacity. Exposures are typically 20 seconds. So you can do basic Astro Photography (AP) with modest altaz setups and get results which are better than eyeballing through a much larger visual scope. So as an alternative, how about a 150P Virtuoso for visual and then add a 60mm frac for basic AP? And just a quick plug for EEVA, it's so quick and simple compared to traditional AP and shows you much more than visual. It's quite addictive....and cheap!

Had a brief session to see how wide a view I could get with my Zenithstar 66 and binoviewers. The result was a respectable 1.7 degrees at 39x. Stars were beautiful pinpoints and I had some nice views of the clusters in Cassiopeia and Cygnus and some doubles. Jupiter and Saturn looked good even at this low magnification - low power views of Jupiter really highlight the Jovian system with its satellites.

Interesting to see the ZS66 outperforming the C6 so much on Saturn. I also use a prism diagonal on my ZS66 and I haven't noticed any CA at all - it might be there if I were to look really hard, but if it's not obvious and is not interfering with the observing, then it's effectively absent for me! I find orange and red stars stand out really nicely with this scope, perhaps the 'semi-apo' glass helps there.

Great report Stu, it must have been good for the soul to observe pre-dawn and then watch the sky brightening. Good tip about the bright light stimulating the cones - I will try this. 👍

Fascinating report! I found similar when comparing my 102ED refractor and my C8 on Mars a couple of years ago, although the smaller scope had binoviewers. The full report is here for your interest. I also tried my ZS66 with binoviewers on Jupiter and was suitably amazed at the detail it showed. 🙂

That’s a great idea, think I might do that next time I have a decent session to report on in detail.

Hi and welcome. Great choice of scope, you’ll see some wonderful sights with that. 🙂

Vintage Vixen heaven in matching hammered green livery. Lovely stuff, should be a joy to use 🙂

Lovely report. SVBony do seem to be producing some nice products, this scope sounds great. I too have struggled with the Crescen over the years. The best I have managed is seeing the upper part of the crescent, with my C8 and a UHC filter I think. I did also see an oval smudge in the right place in my 130P, this time with an OIII, but no crescent shape. But I’ve never felt like I’ve really ‘nailed’ the view, and I feel that you need the right combination of aperture, magnification, filter and dark sky to really get it. One day……

Well, hey, that’s more reaction than I’ve ever got from my wife! You sure that’s not the headphones nebula?

Totally agree, I love simple, tech free observing. Sometimes I re-live the excitement that I felt when I first viewed objects like the Ring nebula, Orion nebula, Hercules cluster and Jupiter and Saturn, over forty years ago. It’s also good for your mental health!