mikeDnight

Not a good night as there was light cloud and turbulence at the time of observation.

Hi Adam, It was Prism's experience that was quoted and not mine. It confused me to initially, as it begins with "mikeDnight". Anyhow, from a personal point of view I've never seen a triplet of any make produce a visual planetary view that was meaningfully better than that produced by a good doublet. For me there are more drawbacks than gains when it comes to triplet apo's. With an FPL53 doublet, the colour correction is so well controlled that the added cost, weight & cool-down time of a triplet just isn't worth the difference. Visually a FPL53 doublet could be considered apochromatic, because the scope itself produces very little residual CA; and many older triplets, including the likes of AstroPhysics, can show more colour than a modern FPL53 doublet. Often it can be local conditions that produce colour fringing. Thin cloud or haze can cause a colour fringe around bright objects, and the UK is often cloaked in some degree of haze or cloud even on apparently clear nights. Eyepieces, particularly wide angle designs, can create a colour fringe if the eye is slightly off axis. And of course atmospheric dispersion and turbulence play their part too. So I'd happily grab a good doublet over a triplet without ever believing I've ended up with a raw deal. Conversely, if I had a good triplet, I'd use it to its full potential.

Martin, may be you should take a look at the video on the Technosky refractor thread on this forum. It's a small but impressively capable 102mm ED that could be worth considering.

That was a wonderful video Victor, and your refractor looks fantastic. Terrific image of Mars too, and the high magnification you used during observing is testement to the scopes fine optics. Watching your video and listening to your experiences with planets as well as deep sky, it seems you and your scope will have many happy years of observing to look forward to together.

I'm not a fan of the Dob mount for lunar & planetary observing, although I'm not totally aversed to using other altazimuth style mounts. I think a SW 150L F8 on some sort of gyro style mount would be a nice planetary scope. It would glide more easily than a Dob and could be set at any height for comfort. The SkyMax 127 & 150 are a good choice too, both able to show wonderful detail. Nothing quite matches a refractor for sharpness though, but there's the smaller aperture and higher price bracket to consider. A 120ED is still quite a beast, but if 102mm is an aperture you'd be happy with, there are quite a number of very nice ED's at around F7 to choose from that may not break the bank. And I didn't use the T word! ☺

Sorry your C8 is crying Steve. If it makes your C8 feel any better, it was actually a C8 that gave me one of the best views of Jupiter I've ever had. It was an old 80's Orange C8 who's owner was desperately trying to sell on. I reluctantly looked through the scope and was blown away by the view, and so was its owner. He changed his mind about selling it after that. So some can do a great job and Celestron always seemed to be better than Meade for some reason. I'd love to look through an old Takahashi SCT, but they are as rare as hen's teeth and no longer in production.

With watching TV as an alternative, I can't imagine Andrew burning the book anytime soon, matter how masochistic it may be.

You should put that back into its cell, otherwise you could void your warranty. 😭

That looks like a lovely fireside read for those cold winter nights Andrew.

Hard to imagine isnt it! 😲

For visual planetary observing I would say "yes"! From personal experience, and I've literally used hundreds of SCT's, they are the absolute worst visual scope in existence for planetary. In forty years I've only once seen an SCT give an acceptable planetary view. Everything else is a better option! As an imaging scope SCT's can be great, but visually they give the softest, definitionless view imaginable. For visual planetary definition is everything, and a Newtonian will outstrip the same aperture SCT, but so will a smaller aperture Maksutov Cassegrain. So it's not the Cassegrain design that's the problem, its the fourth order curve of the Schmidt corrector plate. They are a visual observers nightmare! If you're in any doubt, try comparing star images between the SCT and the Newtonian, Maksutov Cassegrain, classical Cassegrain and refractor. As for changing the SCT for a 102mm ED refractor, the view will be sharper but dimmer. Image scale can be increased but local seeing conditions may not always allow the use of very high powers.

"When I see your heavens, the work of your fingers, The Moon and stars that you have prepared, What is mortal man that you keep him in mind, And the son of man that you take care of him?" (King David - Psalm 8:3&4). When you take the time as you have, just to sit back and meditate on the awesomeness and history of observing the heavens, and contemplating all those who have gone before, we can't help but to be awestruck by the magnitude of everything we see. Of course many of those who went before had clearer and darker skies, but no telescopes. Which would be better? I'm not so certain!

Nice sketch Dave! This could be the start of a very slippery slope. ☺ I'm glad you enjoyed it and am looking forward to seeing more in the near future. When I get chance, I'll dig out some of my sketches from 30 or 40 years ago, and share them with you privately. You'll feel good about your first sketch after that! 😂

The best views of Mars for me were back in 2003 while using an 8.5" refractor. The detail was so intricate as it flickered in and out of view that it couldn't be drawn. After that, also in 2003 were the views through my Tak FS128, which left all other scopes standing, with the exception of the 8.5" achromat of course. The views I had in 2016, using a Tak FC100DC while Mars was skimming the roof tops here in the UK, is also highly memorable. Mars was only around 16" arc at best, yet with its northern hemisphere turned toward us, the small refractor delivered some amazing views of the planet's albedo features. So far this apparition, using a FC100DZ I've had some wonderful views, and hopefully there'll be many more to follow.

Yes it was! I'll often use a binoviewer but forgot to mention it in the write-up. I got the magnification wrong too. It should say X165 which would be nearer the mark. Sorry!

Thin cloud caused some turbulence but during clear spells I had some nice views.

Sorry, I can't help myself! 😊

Lovely sketch Lee! If youre interested, the BAA handbook indicates that if the time of your observation was UT/GMT, the CM would be 188°. If at BST it would be 173.38°.

Obviously it's not only the cloud here in Lancashire that's thick Andrew. I should have said "quite thick but not so much so as to completely block the view." 😂 I don't have the 8" any longer though, as I prefer the higher definition views through one of those mythical beasties that don't show diffraction spikes! 😈 .

I love the old Vixen's! I bought a Vixen 102mm F13 back in 1986, and to this day that scope remains one of the best refractors I've ever owned. And yes, it was an achromat! I probably didn't even get the best out of it, as back then, good eyepieces were hard to come by and relatively expensive. With what I had in way of eyepieces, that scope gave beautiful views of the Moon and planets, but at F13 some might think it would be poor on deep sky. Well theye'd be wrong, as the scope was stunning on deep sky. You may laugh, but my deep sky eyepiece was a 40mm Vixen Kellner. That eyepiece in the F13 was awesome, sharp and utterly transparent. It gave me perhaps the finest view I can recall of M81 & 82 I've had in 40 years of observing in any telescope. I knew when I sold it that I was making a big mistake, but I needed college A level text books, and at the time it seemed the only thing I could do. If I had my time to do again, I'd keep the scope and throw my time at college and university studying mathematics and the natural sciences to the wall instead.

Are they expecting you to pay for that? They after all are the ones causing the problem in the first place!

I've got a carry handle on my DZ!

Congratulations Jeremy! ☺ Wow, you sneaked this one up on us!!

In no particular order: Celestron, Skywatcher, Orion USA (not Orion Optics UK).

If I'm correct, the 150P is F5, so has a focal length of 750mm. If you divide the focal length of your scope by that of the eyepiece you're using you'll get your magnification. Eg. 750÷10 = 75X. A 2X barlow will then give you 150X and a 3X barlow 225X. Both are good powers for Mars, but your scope needs to be perfectly colimated and thermally stable. Also, the local seeing conditions need to be good with little or no turbulence. A misty night may give better results than a truly clear night. Accurate focus needs to be maintained too, and you'll need to study the tiny disk carefully for 10 or 15 mins before all the subtle detail shows itself. Sometimes an orange filter will bring out dark markings while a light blue will show ice caps, clouds and mists.