melsmore

Would that include "During the favourable opposition [of Mars] of 1892, W. H. Pickering observed numerous small circular black spots occurring at every intersection or starting-point of the "canals"? 😁

Thanks, very interesting link - especially the conclusion in section 5.1.3. I've always thought that the average cell size here is fine for telescopes up to around 12" ( can't remember where I read that) and I can't say I've ever changed to my Mak127 or TS80APO because of seeing. I've often had to wait one or two hours for my C8 to stabilise thermally though, and when I had an 8" Newton, I often had to swap to one of the others due to meteorological wind. CONCLUSION What all this implies is that it is possible for a significantly smaller aperture to outperform the larger one, but it requires them to be, and remain at a specific seeing error level, generally involving compromised seeing conditions. It is only possible when D/r0 in the larger aperture is ~4, or larger, in which case a smaller aperture with D/r0~2 will have - all else equal - better resolution and contrast transfer. In other words, smaller aperture could perform better while the seeing error is large enough, but if it lessens sufficiently due to seeing fluctuations, larger aperture would rebound and perform better. Typically, seeing fluctuations are wide enough for that to happen.

Celestron Skyris cameras are Imaging Source. They say "Skyris cameras are not ASCOM compatible. However, they do work as DirectShow cameras with generic webcam software." I haven't tried it but there is an ASCOM driver for DirectShow here http://www.hristopavlov.net/ASCOM/ You could try that.

The second one looks better on my tablet too. Really good.

and Christmases too!

Dunno, on their web site page it says "Baader Colour Filter Light Blue 1¼" (470nm) " , but "blue" on the box. Looking at the spectrum, it goes well into the green, so I would say it was light blue (the filter looks light blue too). U guess it got lost in translation from German.

Think it is light blue, the dark blue filter spectrum cuts off before green.

Brilliant!

A good red light does help. I use one of these Ebook reader lights with some red cellophane over it.

I saw it too.

Tricky. The top one shows more nebulosity, while the bottom one shows the dust lanes better.

Excellent sketch, thanks for sharing.

Maybe be add another one at 90°. If my Auntie's power goes off, I'll know why!

I don't think this scope is available yet in the UK. We only seem to get the DC, DF and DL.

NOOO!! DON'T DO IT !!!!

Phew, thank goodness, I thought you'd got it to polish your Taks ?

Me too!

Absolutely. ( And Flames can be red, yellow, white, blue etc too anyway). There have been a lot of HH on SGL, this is one of my favourites.

It's superb.

Neat layout, but what do you have in there? I can't tell from the photo.

Looking good!! Where's the piccy of scope on mount??

Long case clock with glowing moon phase globe would have been awesome ........ Hand designed and printed long case clock without globe will still be awesome!

Here's my humble offering. Mostly UWANs - which I like a lot - William's Optics or Sky-watcher branded. The Vixen Lanthium 8-24mm is excellent - very underrated, in my view. There are some filters and cleaning stuff in the lid! The thing with the ring is a Celestron red-light, and the black thing at the top is a Rigel PulseGuide Illuminator for the Baader Micro Guide. The bendy thing is a red light clip on e-book illuminator. I'll replace the 25mm Celestron Plossl with a 12.5 Ortho at some point.