markse68

On 23/10/2023 at 21:23, i2000s said:

Where did you get your tripod? It's an interesting structure!

It’s an old military “fire control” tripod gifted me by a friend years ago. I’d hoarded it for years as i really like its construction/design and finally have a good use for it  I’ve seen a couple come up on ebay- popular with hipster lamp builders…

Mark

Sorry to hear you were ill Joe- come to the next one. It was a very good meet shifted to the Sunday due to weather but we had really good clear skies and a great turn out- in the region of 70 (!) people was the estimate and loads of scopes out. We were rushed off our feet all night! Excellent views of Jupiter and Saturn though the somewhat enhanced local light pollution from a funfair made favourites such as the Ring and Dumbbell nebula nigh on impossible for the visual observers, not so much a problem for the few robotic scopes though. Really good fun evening  

Mark

You make really beautiful things Keith 👍 Hopefully this works out and you get to use it more than that other beautiful scope you made. 

(I have that same hoover too- they’re great  )

Would be great to meet you Joe- I’ll be there 21/22nd this month- can’t make the 14/15th but yes they’ve changed it this year to twice a month meets so hopefully lots of opportunity to dodge clouds 🤞

Mark

Yes I’m Greenwich way- but not so far! If you get a chance do come along to the Flamsteed meet-ups- they’re quite regular this year but i’ll miss the next one. Always a very pleasant evening 

Mark

Haven’t bought much astro related recently but always fancied one of these but could never justify the price until this one showed up on abs. It’s got some really nice features- i like 👍 

Mark

10 hours ago, Stu said:

I could add a ‘near miss’ to this topic. In my early days of astronomy, heady with complete ignorance, I coveted a Cape Newise 8” scope as advertised in Astronomy Now, I guess. Fortunately funds would not stretch to it, so I escaped that particular nightmare!

Funnily (🤔) enough a Newise was actually my worst and most frustrating purchase  I struggled for ages to collimate the scope- it hinted at wonderful views but couldn’t make points for stars. I ended up sending the secondary assembly to a seemingly very helpful and enthusiastic Newise expert owner in the US to see if he could remove the secondary mirror which i suspected wasn’t flat. In the meantime I found the real problem was the primary- a large chip on the concealed back surface had rendered it pringle shaped. I found an optics expert who could grind me a new mirror for a seemingly reasonable price (8” f3 spherical is hard to find) and was contemplating going for it but in the meantime things got strange with the US guy- he still has my secondary assembly and keeps “forgetting” to return it more than a year later. I’ve given up now. It almost killed my astro mojo completely. But the planets are back, cobwebs dusted off my simple trusty Tal newt and life goes on. 

Mark

Interesting video about new theories for globular cluster formation. Fascinating objects and i think my favourites

Mark

cool- how much is a new draw tube with BF?

Mark

13 minutes ago, tomato said:

The Starsense unit has been transferred to the 16" SW Flextube Dob, works fine on there even though it is mounted slightly to one side of the vertical axis of the OTA.

Now looking at options to not disappoint my grand daughter when I hand over the Celestron 80mm Achro...

if you diy a phone mount for your dob then you should both be able to use it- you should have a few uses of the activation code. Several of us have diy’d mounts:

Mark

22 hours ago, JeremyS said:

Here is the light curve of Chi Cyg from the BAA Variable Star Section Database. It looks like it has just passed maximum:

Excellent stuff Tim and I wondered what the kink in the brightening phase was- if it was due to missing periods of capture or something but the light curve Jeremy posted shows it clearly and it’s a common trait on longer period variables apparently-

https://www.aavso.org/sites/default/files//publications/staff_pubs/templeton_mira_humps_bumps.pdf

Mark

The Tal 120 is a bird jones i think with a correcting optic built into the focuser. These optics are prone to  delaminating so check it well before buying. But i think they were good quality scopes and nice and compact 

Mark

Excellent find Peter. My hunch is the anodising is harder than the melamine surface of formica but like moonlight focusers, the softer foundation material (alu) will lead to eventual wear esp with abrasive dust. BUT it’s cheap enough to replace and easier to work with so looks to be most excellent! 👍 If I do ever get round to building my 12” for which i have a beautiful mirror in a box, I’ll give this a go- thank you. Nice bit of bling too

Mark

How could it work during the day if it needs to see stars to work?

Mark

14 hours ago, John said:

This sketch by a member of the CN forum might be useful. I saw a couple more stars than it shows with my 70mm refractor, but only just !

 

 

 

Hi John, do you know what fov this sketch was? It looks quite different to this sketch also from CN. I’m struggling…

edit- I see both star patterns in the chart- the ep views are just very different fov- this last one is 150x. And was through a 14” newt. So the chart and all these sketches are newt view? Edit just noticed the compass markings on the chart so these are all refractor view 🤦‍♂️ no wonder i couldn’t match the stars. This is newt view 

Pentax made a range of refractors which are very collectible now and supposed to be excellent. I believe Canon make the optics for Takahashi? Shame Canon don’t make telescopes but they focus on more mainstream consumer/professional markets.

Mark

The phone can do what your eye can’t- integrate over long exposure. So it can see more stars than your eyes can. I’m in bortle 8-9 SE London and it works well. It loses the platesolving close to the horizon but then the imu in the phone takes over and gets you close enough. I just swing it back up more vertical to re-register it every now and then.

Mark

Thanks Nik- very useful- will hopefully have another attempt tonight

Mark

4 minutes ago, Sunshine said:

Thats great, i don’t recognize that module, looks different than my module on my dob, yours seems sleeker and less bulky, is that an official starsense module? I like yours more lol

it’s a diy mount i made for my old iphone- bit less bulky than the Celestron universal mount yes

Mark

23 hours ago, Sunshine said:

You say you mounted the module at 45 degrees from top so that module sits approximately where a finder scope sits on a dob and it works fine? interesting, i know a couple of people who relocated theirs after finding it was iffy when mirror was aimed at sky off from top center. 

Yep- 45 deg from top dead centre. I have it on a tri-finder bracket with the rdf vertical. Was using it last night and it works fine. I don’t know if it would work better if it was level but it seems to work ok like this. Mark

They are lovely lovely things. I just fitted a 1.25” (for lunt i think) ft single speed focuser to my Tal newt. I didn’t want to go up to 2” as i didn’t want the added size and the scope doesn’t do well wide angle- it’s a 1.25” only scope. The focuser is more reasonably priced though still quite expensive- $280. I had it delivered to a friend in the US and picked it up last month when i visited for work. Dual speed would have doubled the price. Dual speed adds inertia and makes focusers feel smoother than they really are but after slackening the tightness of the single speed shaft against the focuser barrel this one is delightfully smooth and feather-touch. A big upgrade over the Tal r&p which had tight spots and slack.

My imaging scope came with a  2” dual speed ft and it is lovely too- I got really lucky. It supports over 1kg of camera etc rock solidly and the way the lock works is superb. it really solidly locks but 1/4 turn of the lock screw and it’s silky smooth to make fine adjustments to the focus 

Mark

so cute! 🥰 

Spent about an hour trying to identify it last night with my 6” from bortle 4-5 but gave up. I was looking in the right area- starsense got me there and confirmed with star pattern in finder/skysafari but could see no trace of M101 and struggled with star pattern in ep (20mm). So i think i probably did “see” it but couldn’t identify it. But that doesn’t really count does it haha. Goto with platesolving would have been a godsend or being better at starhopping…

Mark

My experience of vintage Pentax bins isn’t that great- in the 70s they used a weird gold metallic coating on the eyepieces to increase contrast (i think)  but it oxidises and wipes off if you try to clean it. Mechanically they were nothing special either. Haven’t tried every variant though.  I know you said don’t mention others but Nikon and Fujinon vintage bins are nicer I think 

Mark

3 hours ago, RobertI said:

It will be interesting to see what they come up with there, and also interesting to understand how restrictive Celestron’s patents are in this area (I did some research here  out of idle curiosity, but by no means comprehensive). 

they’re linked in Roberts’s post above

Mark

12 minutes ago, AstroKeith said:

The second patent is careful to restrict to manually steered scopes.

If you designed a software to guide a users phone to a target and they just happened to strap it to a telescope with some rubber bands unbeknownst to you, i wonder if that would infringe on that patent? 🤔