lenscap

I tried a B-mask on Mars recently.

Instead of 3 razor-thin intersecting lines you get 3 bands, each about the width of the planetary disc, so it's not very precise and I didn't find it useful.

Near the top right of this page click on the small globe icon.

At the top of the window that appears, click on "Notification Settings".

In the large window that appears, select the type & method of notifications that you want.

1 hour ago, Mary1976 said:

or there is also a Helios locally.

Hi, do you know the model name & number of the Helios scope?

Helios scopes were rebranded as Skywatcher in 1999 so the scope would be old but should be good quality, ( but avoid the "Apollo" models.)

I have a 20 year old Helios Explorer 200p that performs almost as good as new.

Saito Optics, Japan, a division of Edmund Optics Inc ?

https://www.edmundoptics.co.uk/company/about-us/75th-timeline/

Spotted this for sale on Facebook.

Perhaps it's a new model from First Light Optics ?   Sorry ! 😀

28 minutes ago, Aquavit said:

Am I right in assuming that polar alignment and the technicalities of the EQ mount only come in to play when I want to find something using co-ordinates or tracking an object. In other words, for easily located objects, I can just point and "shoot"?

Yes you don't have to polar align an EQ for visual observing, you can just point & observe.

But doing an approximate polar alignment will make observing more relaxing since you can manually track an object for quite a long time using just the RA slow-motion knob, rather than tracking on both axes.

For an approximate PA;

      Set the latitude (which you have done)

      Level the tripod as best you can, with the N mark pointing to Polaris (if you can see it) or just approx North.

Enjoy!

Welcome to SGL.

Why settle for taking just one scope with you? 😀

This is a matter of personal preference, there is no "right" answer.

Factors favouring a manual dob;

      - if you already know your way around the sky, learning to "star-hop" will be easier.

      - are you patient, with a long attention span?

      - if you have fairly dark (rural) skies, you will have  a lot more starting points for your star-hops.

      - if you enjoy the thrill of the chase as much as observing the target.

Factors favouring a Goto dob;

      - easier to find targets for a beginner, but you will still have to recognise enough bright stars to align the scope.

     - if you will be easily distracted by having to regularly nudge the scope to keep the target in view.

     - if you have urban/suburban light pollution.

     - if you prefer observing targets to searching for  them.

I started with a manual scope and had great fun, but changed to Goto when I found myself gnashing my teeth in frustration after sometimes spending  an hour or more failing to star-hop to a target in light-polluted skies.

Perhaps you could buy a used manual dob. If it doesn't suit you could sell it for more or less what you paid for it & switch to a Goto. Good luck with whatever you decide; decent new & second-hand scopes are in very short supply at the moment.

Nice work!   Is it worth testing a scrap of the leatherette to see if it heat-shrinks?

If so, applying some local heat might help to get  it to conform to curves, or remove or reduce bubbles & creases.

14 minutes ago, banjaxed said:

It isn’t the eye guard but the bottom section that attaches to the diagonal that moves out.

Everything's relative. 😀

If you grasp the upper (largest diameter) section & twist the lower section clockwise then everything, including the eye lens, moves away from the upper section, which reduces the available eye-relief.

23 minutes ago, banjaxed said:

The barrel travels out approximately 2 cm

Mine does that, though I estimate it moves about 1cm.

I assume it is a twist-up eyeguard used to achieve a comfortable amount of eye-relief.

The eyepiece assemblies on my Skywatcher & Orion versions were screwed into the main tubes. They are easy to cross-thread though so I would put on a rubber glove & apply as much torque as possible.

Mine is   M16 x 2mm

On 30/10/2020 at 01:28, stringB said:

The mount weighs only 4.7kg so I’d like to leave it rigged by the garage door and just walk out with scope mount and tripod.

CEM25                      4.7 kg

1.5" tripod                5 kg   (2" is 8 kg)

150p     about          5  kg  

Counterweight say   5 kg

Total about 20kg and very top-heavy.   Could you lift it?    Sure, but I wouldn't call it lightweight.

Would an SCT on an Alt/Az goto be more portable?

15 minutes ago, martin__newbold said:

Does anyone now how large the SkySafari  pro android app is i have a dinasaur phone and the demo was 320MB a tight squeeze a need a version with net control for telescope is this only available in pro version now   ?   I cant find out is specification on size anywhere.

Both "6 plus" and  "6 pro" have telescope control.

Plus needs about 600MB,  Pro about 2GB.

Detailed comparison here; https://www.skysafariastronomy.com/

Discussion of storage requirements here;

https://support.simulationcurriculum.com/hc/en-us/community/posts/360015877874-Storage-requirements-for-SkySafari-6-versions-

Clear skies.

In the UK you can tell that Christmas is coming when the supermarket aisles are blocked by pallet-loads of Quality Street, Cadbury's Roses & other confections.

Inspired by this thread, I decided to make a Bahtinov mask for my Helios (Skywatcher) 200p F5 ; 

The Roses lid is almost the same size as the 200p dustcap.

I downloaded a template from here;   http://www.deepskywatch.com/Articles/make-bahtinov-mask.html

The 8" template prints on  2 sheets of paper ,which is a nuisance, so I used the 6" and enlarged it to just fill 1 sheet of A4.

I stuck the print to the lid of the Roses tub with a few bits of double-sided tape and used a bradawl to pierce the lid at each corner of each slot, then removed the paper and cut out the slots with a craft knife. A couple of coats of grey primer and one of matt black and here is the mask.

It works a treat , (with or without the paint ) on the 200p and on my 6" Newt as well. If you prefer Celebrations to Roses  I think that lid is a bit bigger so you might not need the rubber bands.

Now that I've ruined the lid, we will just have to scoff all the chocolates double-quick. Yum Yum!  😀

16 minutes ago, johninderby said:

Bet they have ruby coated lenses. 😁😁

They must be good John, even Bresser list them.  😉

https://www.bresser.de/en/Discontinued/Yukon-NRB-30x50-Binoculars.html

14 minutes ago, tomato said:

can you have such a thing as a triangular black hole?

I think Roger Penrose could probably prove mathematically that triangular black holes are  not only possible but are an inevitable consequence of General Relativity.  😄

If you don't already have a celestial guide-book I suggest you get;  

https://www.firstlightoptics.com/books/turn-left-at-orion-book.html

It will show you how to find hundreds of interesting objects by "Star Hopping"

45 minutes ago, neiil phillips said:

Hi lenscap What tripod would fit the old eq3 head do you know ?

The ally tripod that comes with the current EQ3-2 also fits the old black EQ3.

https://www.firstlightoptics.com/equatorial-astronomy-mounts/skywatcher-eq3-2-deluxe.html

The 1.75" tubular steel (EQ5) tripods also fit, though more  expensive of course.

Hi Neiil, and welcome to SGL.

The EQ3 head is far superior to the EQ1, but you will get no benefit by mounting it on an EQ1 tripod which is just too flimsy.

As said, I suggest you try to find a second-hand EQ3 tripod. Although it is also extruded Aluminium it is a much more substantial affair than the EQ1 version & will easily cope with a 4.5" Newt.

Couple of years ago I was  doing a first night-time test of my DIY Onstep GOTO system. (200p on EQ3-2) The scope was chugging steadily  towards its target with me nervous as a kitten checking for tripod collisons, cable snags ,overheating, while trying not to trip over the laptop.

Suddenly there's a loud THUMP.  Panic!   Scope must have crashed into something. Where's  the abort button?  Stop everything.

Couldn't find anything wrong. Next morning I found a pigeon on the patio, or as Monty Python would say, an "ex-pigeon", but what had it crashed into? Upstairs a bit later I noticed the back bedroom window;

And there was the ghostly image of the former pigeon in full flight. It must have hit at maximum airspeed & just dropped stone dead.

25 minutes ago, Grumoyjock said:

recently fitted a telrad as I'm terrible at finding stuff and thought it would help however I'm clearly just incompetent

Hi George, and welcome to SGL.

I think you may need a Celestial guidebook. This one will help you find lots of interesting objects by "Star Hopping."

https://www.firstlightoptics.com/books/turn-left-at-orion-book.html

Even if it's the current model with the hex focuser your seller is asking 87% of the new price!

Around here we would say he's "having a laugh."

In your position I would offer £200 & go to £220 if necessary.

If he agreed I would have a worthwhile discount on the new price.

If not I would buy new and get the dealer support, extended warranty and no quibble returns policy.

37 minutes ago, glennbech said:

Can I hack or make something? I am proficient with a solder iron, arduino and my 3D printer. 

Hi glennbech,

You could build a goto system (which includes tracking of course) for your dob using Onstep;    https://onstep.groups.io/g/main/wiki/3860

Select the "Showcase, built with Onstep" link & scroll down to "Dobsonian Mounts"

Good luck.