Kirby301

@Louis D

I've read the bst eyepieces have removable eye cups and 16mm eye relief, im not sure how much of that eye relief would be usable?

Thanks for your reply @Louis D

I would like to carry on with the bst range but its all going to come down to what the dioptrx fits and at what price, televue are simply out of my budget hence the meade 4000 range.

hi all,

What is the quality of the meade 4000 series eyepieces like?

I have read that the televue dioptrx fits onto these and am seriously thinking of trying this out, can anyone confirm?

Many thanks.

Thanks for all the replies.

I'm currently using the skywatcher supplied 25mm eyepiece and an 8mm bst and combine them with a 2x Barlow. I think the weakness of the 25mm is showing through with regards to eye relief.

I cant wear contact lenses, ive tried but I can't get them in my eyes, they get close and I back away.

I like the idea of the dioptrx, its an expensive option to see if it works or not, especially if its like marmite, either love it or hate it,I will look into it.

Does it fit on all eyepieces?

I would have to use the 2.5 version, shame they don't do higher 

Many thanks 

Thanks for your reply @vlaiv

I do wear glasses, however not at the eyepiece. I have tried but the view isn't as good being further away.

My dominant eye is my left eye, naturally I use this one as the right one gives a bit of a hazy view.

Unfortunately my left eye is like a "rugby ball" to quote the optician. 

hi all,

In a previous post I thought I was experiencing problems with the spider vane creating spikes, this is mostly true. However, I tried doing some observing with my binoculars and was  still experiencing the spikes.

I booked into the opticians and was told I have astigmatism. Now where do I go from here?

What can I do to overcome this problem or was make it easier?

Many thanks.

I've hopefully found a good way to do the aperature mask. I've cut down a plastic straw to the size of the stalk, then down the length of it so it will wrap around the stalk.

I've cut out 3 penny size circles out of a cereal box and stuck them onto the stalk.

Now I've just got to test it out!

I won't be keeping my telescopes in the shed from now on.

I will only be do the visual aspect of splitting doubles not the technical type!

Wow!

Thanks for explaining that, I fully understand now.

By doing the circles on the stalk I will keep most of the aperture and hide the stalk which will lose the diffraction spike, rather than one bigger hole which will hide the stalk but lose alot of aperture aswell as the diffraction spike?

I'm pretty much set on a mak 127.

I'm a curious type of person so I'm going to try the aperture mask, the way John has described on Almach and see what difference it makes.

15 hours ago, vlaiv said:

Unfortunately, this is DIY thing as far as I know.

Actually scratch that, according to this thread:

You can apparently order those online, like from here:

https://www.fpi-protostar.com/crvmnts.htm

If you want to DIY those, you'll need a thin piece of metal that you'll bend into shape (smoothly) - 180 degrees one works good.

Things to remember when choosing spider support - you need at least 180 degrees arc - less than that and you'll have only partial diffraction - only in certain directions and not evenly spread.

Length of support is related to strength of diffraction - keep the length at minimum.

Make sure all "degrees" are covered equally - having for example 270 degrees which will be 180 + 90 degrees - these 90 degrees will bias diffraction to one side.

There is a free software that will calculate resulting diffraction from central obstruction (and support) - let me see if I can find that for you.

Unfortunately I can't seem to find it, but @sharkmelley used it back in 2013 to explain some phenomena so could possibly provide a link to that?

(I found link to software in the mean time):

https://www.cloudynights.com/topic/547413-where-to-find-maskulator/

I just thought of a very quick way to remove diffraction spike on Heritage 130p - it is very easy thing to do and in principle it is "external" to scope - no modifications needed, but you will need to make aperture mask.

Take cardboard and make mask that you will place over the stalk that holds secondary mirror. Be sure that you have nice clean cut.

So it is just a series of circles (can be smaller or bigger) that you tape together to cover the stalk. Just be sure you secure them in place and they don't fall onto your primary mirror. Black cardboard works the best of course.

This will remove diffraction spike.

 

 

I've been reading and watching YouTube regarding the aperature masks. I like the idea alot. They all seem to do a single hole though. Could you explain in simple terms for a simple mind the way you mean please?

I think the mak is going to be the best option too.

How long does the 127 take to cool? I'll be keeping it in a wooden shed.

On 04/01/2020 at 17:10, fiestazetecmk2 said:

Slow motion controls for a dobsonion. 

Built not bought.and works very well.

 

That looks very professional @fiestazetecmk2

You should put up some plans/parts list

OR 

Start taking orders and start selling them

Unfortunately I would have to include a mount in the budget too 🙁

I will have to try the aperture mask on the 130p.

So so much to consider! 

I can narrow down easily with budget.

I would say around £500.

No apos or big maks then 😆

I saw the cr6 in the for sale section and immediately liked it, only problem is with a big refractor comes a heavy mount, im used to a heritage 130p!  and its in Wales!

This brings me onto the maks and the portability of them.  I was looking at the skymax 127 but then heard about the long cool down times.

Ideally I would like something easy to grab and go, not have to wait too long for cooling down and to see a good amount of doubles with  and for £500 🤣

Unfortunately I know there's not something like that unless I do go down the newtonian route, @vlaiv any good links to curved secondary support I will have a look into it.

After learning about diffraction spikes on reflectors I'm left wondering what telescopes everbody else uses for the doubles, the diffraction spikes annoy me so I'm looking for ideas for my next telescope.

Thanks for everyone's help. After reading all the replies it seems it is obviously a diffraction spike from the single spider vane. 

hi all,

I want to start splitting double stars.

However, I've encountered something that may become a problem on my first star!

I have a skywatcher heritage 130p and I decided to split Almach. I used my standard 25mm and then my 8mm bst eyepiece.

I split it, but I had a spike coming off of the primary that was close to blocking the view of the companion star.

What causes this to happen?

The telescope is stored in the shed and is the first thing bought out to cool down.

The eyepieces are left with it to cool down.

 As I wanted to do double star work I know I needed to be accurate with my collimation, I followed the astrobaby collimation guide to a tee, i also collimated my laser collimator and checked it against my own collimation. I did a star test and with the star fully defocused I can see the 3 clips around the edge of the mirror the vein and the secondary mirror. Everything was centred and evenly spaced. I'm 99.9% accurately collimated.

The only other things I can think of is its either my eyes or maybe its not the best telescope for splitting doubles.

Any advice would be greatly appreciated.

Many thanks.

The video grabber came yesterday so I decided to see if it worked.

I managed to find the scb2000 under the OEM camera, after playing in the side bar I managed to get a view of the setting menu on the screen.

However, I put the scb2000 in the scope but no stars came up onto the screen, I centralized stars into the middle of the eyepiece, I tried to focus using the truss of the heritage 130p, all to no avail.

Any ideas?

Hi all, 

I bought a Samsung scb2000 to use as an eaa observing aid. Last night I got to try it out and the amount of setting up it took was a bit tedious, infact I gave up and just did visual observing instead.

However, I saw a meteor and thought how about a more permanent setup for the camera to capture such events.

What camera settings would be best to use for this kind of setup and what software would be best to use?

Many thanks.

Oh yes, I ordered one of them, I'm still waiting for it to arrive.

I remember reading something about a flip mirror a while ago, i could of done with one last night!

I'll put it on my ever growing list.

Yeah it was definitely vega, Venus was around the side of the house at the time. It's a nice clear night now, shame I can't take advantage of it!

A little clear when I got home with Vega sitting a little above the tree line.

I decided to try out the samsung scb2000 on my heritage 130p. No tracking yet.

Put the settings in for planetary nebula and globular clusters from a list that was given to me in another thread.

Now, with no tracking and no focus it took a while to find Vega. I found it in the rdf and then the eye piece,  then in went the camera, out went the camera, in went the eyepiece, out went the eyepiece etc, etc.

A lot of jigging about later and it kind of looks like a star, if you squint your eyes!

However, just as it looked like I was starting to get somewhere the clouds have come over.

Thanks Davy,

I shall keep in mind the removal of the ir.