John

15 minutes ago, Edward Dewolf said:

I should have have maybe mentioned that I use my main scope for astrophotography with a guide scope.  Would that change much?  Would a red dot finder be good enough then?

Do you use GOTO to find your targets ?

My preference is to have both an illuminated reticule finder and an optical finder on my 12 inch dobsonian. Most of the RDF's that I have tried are too bright for deep sky hunting but the Rigel Quikfinder and Telrad are optimized for astronomy and go dimmer. On my refractors I seem to get on best with optical finders of the right angle / correct image type either 30mm or 50mm in aperture. The optical finder on my 12 inch dob is a 50mm RACI with an illuminated cross hair facility if I want to use it.

There is no right or wrong approach with finders really but it does sometimes take some experiments with different arrangements to find what works best and most successfully for you.

If you buy new, and there is an issue with quality, at least you have some redress.

The ones produced in the 12 months before Comet Halley's return in 1986 were often poor. Apparently both Meade and Celestron relaxed quality control standards to meet consumer demands at that time.

You can get lighter weights:

Rod Mollise's free guide to used CAT's is well worth a read and covers Celestron and other brand SCT's:

https://skywatch.brainiac.com/used/index.htm

The change to being produced in China didn't seem to affect the quality and maybe even improved it:

Mouthwatering stuff Gerry

I've been trying not to buy new stuff lately but I do feel a growing urge to get one of the new Tele Vue Bandmate II O-III's in my filter case for my Veil observing this Summer and Autumn

Return it straightaway.

Totally unacceptable. I expect you knew that really though ?

This is my Lumicon 2 inch O-III. I don't know when it dates from exactly - perhaps 6-7 years back ?. It's a cracking performer

10 hours ago, vineyard said:

..  I've got an old Astronomik UHC - no idea whether its type 1, 2 or 3 as per the semrock website, but I've emailed Astronomik w the serial number to find out (I suspect mine is very old - the serial number begins with 002003... which suggests 17 yrs ago...maybe filters are like fine wine & get better w age? 🤞🏾😂).

 

The serial number on my Astronomik O-III starts 003002 - perhaps it's from the future ?

@Stardaze there you go - you start a thread on the merits of £200-£300 eyepieces and end up getting recommended £1000 ones !

As Gerry / @jetstream says though - your original shortlist are hardly shabby in any way and will show fabulous views

I only bought one of my Ethos new. The 21mm cost me less than 50% of the current list price, thank goodness !

The dew shield probably screws onto the blue flange. If you can find a way to hold the flange steady you might be able to unscrew the dew shield and then you can get to the mechanism that holds the flange / dew shield in place on the tube. Probably a friction clamp / clip of some sort.

Welcome Gary

From John in North Somerset.

I only use the locking screws on my Orion Optics 12 inch when I'm transporting the scope somewhere.

Otherwise I leave them loose.

Try a good O-III on the Owl or the Veil and the difference over a UHC is quite noticable.

The Nikon NAV HW's cost around £980 each I believe. The ES 92's cost £379 each. £600 quid per eyepiece is quite a difference

I didn't mention the Ethos equivilents in this thread because I thought that their price tag would cause a stir.

I'm glad that the NAV HW's are so good

Can secondary adjustments be made with these scopes and those like them ?

2 minutes ago, wimvb said:

And how many stone is the load capacity of your mount?

Limestone or granite ?

It is odd when metric and imperial are mixed but I'm as guilty of that as anybody

I refer to 1.25 inch or 2 inch eyepieces and then give their focal lengths in mm and also to my scopes apertures in inches but their focal lengths in mm

I'm going to use cubits and palms from now on

It was a Baader UHC-S filter that 1st showed me the Veil Nebula, with a 100mm refractor. That was around 10 years ago so I think the UHC-S was quite a new product back then.

I got it because I read (from Baader) that it was designed to have a more generous band pass so would be suitable for smaller aperture scopes. As I moved up in aperture from 100mm I found that "proper" UHC's and O-III's were more effective than the UHC-S. Which is sort of what I expected.

Nothing wrong with the UHC-S though. It is good quality and does what it is designed to do.

Are there any baffles that will need re-positioning John ?

Actually, thinking of it, what are the baffling arrangements of the scope ?

I use one of these with my 12 inch F/5.3:

Cheap, simple and it works.

Hi,

The 2.3mm gives 174x magnification with the 70mm Travelscope. The scope is designed as a portable low to medium power instrument. 100x is probably about as far as you can push it really.

When I visited the Herschel Museum in Bath (highly reccommended by the way) I was struck at the really short focal length eyepieces that the Herschel's used when observing. Apparently over 6,000x magnification on some occasions

I came across this old paper, held by the RAS, on this topic by W H Steavenson for any that might be interested:

http://articles.adsabs.harvard.edu//full/1924MNRAS..84..607S/0000607.000.html