Oldfort

3 hours ago, Tommohawk said:

Dont try this at home folks!!

It's not hard to use the shadow of the scope, by minimising it, to get a decent alignment, with final tweaking using the finder to project a large out of focus image of the sun on to something handy - such as a piece of paper or the telescope handset.

My best views are to the North and East, so an evening Venus is a challenge (plus it would be over central London).  It finally dawned on me that if I  did an alignment on the sun on my goto, then I could find Venus easily in the daytime.  OK this is not premier league imaging, but it's a start (iphone held at lens; 2.5mm Nagler with TV76).

From Bortle 8 skies, I would add the following:

M51 but only just

M63 - a faint smudge but unmistakable

M94 - relatively easy, even when M51 not visible

These were with a C8.

I also have seen M33 in a 4"refractor, with 50x magnification.  It may have helped that I had been out in the dark, relatively speaking, for quite some time  before I tried for this.

You would need to choose your spot very carefully, to avoid upsetting some of the other night time visitors.  I can't say more on a family friendly site.

It's a bit of a conundrum.  For visual work, aperture rules, but more aperture means more weight.  This is paricularly an issue in respect of portability, which is important to you.  The C8 is significantly lighter than the C9.25 and in the datk desert skies will enable you to see thousands of faint galaxies, nebulae and the like.

For photography, as others have said, stability of the (equatorial) mount and the attached telescope is what counts.  This leads to relatively bigger mounts and smaller telescopes.

And the answer to this conundrum?

More than one telescope!  What's not to like.

9 minutes ago, bomberbaz said:

Just had a eyetest 2 months since but thanks anyway. BTW I have no intention of getting my eyes done. Managed with glasses for best part of 50 years, think I can manage for whatever years god has given me to play with.

 

I wasn't more than 6 months since an eye test when my floaters (and other stuff) went mad.  Check out "Posterior Vitreous Detachment" to see some of the symptoms.

But like you, I'm in no rush for surgical intervention.

54 minutes ago, bomberbaz said:

This also cures your astigmatism but costs around £4K 😳 (per eye)

I was told by my opthalmologist that there is no guarantee of success.  My experience is that the floaters come and then fade away.  If they are a new thing, its worth getting it checked out.

I find Nightcap is OK.  Here's one I took earlier - handheld with a C8 and Nagler 22.  I could really do with something to hold my iphone - getting it lined up was the hardest part.

I'm not familiar with the Orion push to system, so this is guesswork.

C/2017 T2 is relatively close to the North Celestial pole, so  unless you approach an object along a line of right ascension (ie heading directly towards or away from Polaris), both RA and dec will move all over the place.  One way around this would be if there is an alt/az mode,  on the mount and use that.

Conversely, when using an alt-az scope, pointing near the zenith is a challenge.

Also, the nominal magnitudes shown for comets are a bit misleading, because the light is spread over a large area (a bit like the larger galaxies) and unless you have a really dark site, they can be difficult if not impossible to find.

Meade, Celestron and Televue typically use UNC and UNF threads.  I'd extrapoltae from that to guess that other US brands will the the same.  The rest of the world generally uses metric.  An exception is camera tripods which will use 1/4" or 3/8".

Threads on telescope heads don't seem to have a standard, other than UNC or metric.

17 hours ago, DaveS said:

Acme thread table

From dad's 1943 "Machinery's Handbook".

Here's the 2008 version.  Some things don't change.

And the third. Tbh I think this would be as likely to deter people from astronomy, rather than enthuse them.

Here's the second one.

I am quite partial to old star atlases.  Here's the first of 3.

This company may have what you want.  The website has changed completely since I used it last, but worth a look.

https://greentree-eng.co.uk/product/product-protection-finishing

I love my Uni 28, BC&F branded.  For something so light, it feels as solid as a rock.

It spends most of its time outside, on a balcony, so I have replaced most of the bolts and screws with stainless steel.  I'd like to varnish the legs, but I worry that they will just stick together if I do.

I was lucky enough to visit CERN a couple of years ago, whilst it was stopped for upgrading.  Here's some pictures of their first accelerator.  The red thing is the magnet.

I wonder if the problem is that Sirius and Procyon are at similar azimuth at the moment.  Perhaps try Sirius and Regulus.

You don't mention set up for your latitude and longitude.  Sometime mounts come with a default location a very long way from where you are (eg California), and it helps to have these set reasonably close to your actual location, although I think precision is not essential.

On 05/04/2020 at 04:26, George Jones said:

 

The Monthly Notices of the Royal Astronomical Society (MNRAS) is one place.

https://academic.oup.com/mnras

And there's the Astrophysical Journal

https://journals.aas.org/astrophysical-journal/

Lovely evening sky today.  Looking west from Greenwich, over the Thames.  The pointy thing on the right is the Shard, the top of which was actually blue - support for the NHS maybe.

Steinicke's book is fascinating.  You might not expect such an apparently dry subject to be so interesting, but he writes very well. 

Or perhaps I'm a premier league geek.

I too was worried that installing Bob's Knobs would make a real hash of collimation, but I bit the bullet.  I read the instructions several times and then followed them exactly.  I had no problem tweaking the collimation afterwards.  This was on a Celestron C8.

I'm not familiar with Luminos, but if they can do it, maybe Skysafari will also be able to - after all it's been on their to do list for a while.

The Televue high hat 2" to 1.25" adapter might give the extra distance you need.  Of course, being Televue, it won't be cheap.

Sadly I got rid of my Charles Frank catalogue when I downsized to an apartment.  I do have the Charles Frank Ultra Wide angle eyepiece, on an RAS thread, but i don't know its specifications.