Creating add-ons for the Heritage 130p

[Ganymede12]

I've ordered a Sky-Watcher Heritage 130p as my portable, easy-to-move scope and I'm hoping to add to it a little. 

First and foremost is using flocking material to cover up the top half. I've ordered a roll (100x45cm) from FLO and was wondering if you had any advice on building it? 

 

The other thing I want to make is a Solar Filter. The frame doesn't look suitable for one that slides over the top (like I have with my refractor) but I'm envisioning a more plug-like design that fits into the top. Has a design like this worked before? Or is there a better design? 

 

Any thoughts would be greatly appreciated. This'll be the only scope I will be able to take to uni, so I want to make the most of it! ?

[Cornelius Varley]

6 minutes ago, Ganymede12 said:

I've ordered a Sky-Watcher Heritage 150p as my portable, easy-to-move scope and I'm hoping to add to it a little. 

First and foremost is using flocking material to cover up the top half. I've ordered a roll (100x45cm) from FLO and was wondering if you had any advice on building it? 

 

The other thing I want to make is a Solar Filter. The frame doesn't look suitable for one that slides over the top (like I have with my refractor) but I'm envisioning a more plug-like design that fits into the top. Has a design like this worked before? Or is there a better design? 

 

Any thoughts would be greatly appreciated. This'll be the only scope I will be able to take to uni, so I want to make the most of it! ?

Do you mean Heritage 130P, not 150P ?

The Heritage 130P is an semi -truss design so you can only flock the bottom half of the OTA (sold tube part). The flocking material (self adhesive) should be cut into manageable strips and used to line the solid tube from top to bottom lengthways rather than try to do it in one go. For the open truss part you can create a shroud from foam rubber sheet.

[Ganymede12]

Ah yes, It's the Heritage-130P. My mistake. 

 

Also, I completely forgot that flocking was for the inside only and I really need to cancel my order, quickly! 

[Pondus]

I`ve got the Heritage 130p and I would personally consider it way too risky for solar viewing no matter how well build

the shroud and filter would be. You really really have to know what youre doing here.

 

Rune

 

[Ganymede12]

16 minutes ago, Pondus said:

I`ve got the Heritage 130p and I would personally consider it way too risky for solar viewing no matter how well build

the shroud and filter would be. You really really have to know what youre doing here.

 

Rune

 

That's a good point, which brings me onto another idea I had. Could I use this telescope if it was collapsed? I was thinking of experimenting with  changing the focal length and if it would work then I''d use a solar filter only when it was collapsed to avoid light getting in through the sides. 

 

[Cornelius Varley]

13 minutes ago, Ganymede12 said:

That's a good point, which brings me onto another idea I had. Could I use this telescope if it was collapsed? I was thinking of experimenting with  changing the focal length and if it would work then I''d use a solar filter only when it was collapsed to avoid light getting in through the sides. 

 

That won't work. The focal length of the telescope is 650mm and this remains constant and collapsing the tube won't change the focal length.

[Ganymede12]

2 minutes ago, Cornelius Varley said:

That won't work. The focal length of the telescope is 650mm and this remains constant and collapsing the tube won't change the focal length.

But won't it make the distance between the primary and secondary mirror shorter? And in any case, won't it still protect the sides of the telescope from stray light?

[Cornelius Varley]

Just now, Ganymede12 said:

But won't it make the distance between the primary and secondary mirror shorter? And in any case, won't it still protect the sides of the telescope from stray light?

The focal length of the telescope is governed by the curvature of the primary mirror, not the distance between the primary and secondary.

[Ganymede12]

2 minutes ago, Cornelius Varley said:

The focal length of the telescope is governed by the curvature of the primary mirror, not the distance between the primary and secondary.

I see. 

So would the image be too out of focus if I tried to look through  it whilst collapsed?

[Cornelius Varley]

Just now, Ganymede12 said:

I see. 

So would the image be too out of focus if I tried to look through  it whilst collapsed?

Yes. To get an eyepiece into focus with the tube collapsed you would have to use a long extension tube to compensate for the shorter telescope tube. 

[Ganymede12]

Just now, Cornelius Varley said:

Yes. To get an eyepiece into focus with the tube collapsed you would have to use a long extension tube to compensate for the shorter telescope tube. 

I think I might have one of those? 

Isn't it just a plastic tube that puts the eyepiece further away from the OTA? 

[Cornelius Varley]

Just now, Ganymede12 said:

I think I might have one of those? 

Isn't it just a plastic tube that puts the eyepiece further away from the OTA? 

It would have to be a long extension tube and the view you would get would not be very good. The position and size of the secondary was calculated to give the perfect illumination for the eyepiece. If you move the secondary closer to the primary then it will not be in the optimum location . Even more so if the tube is almost fully collapsed.

[Ganymede12]

Just now, Cornelius Varley said:

It would have to be a long extension tube and the view you would get would not be very good. The position and size of the secondary was calculated to give the perfect illumination for the eyepiece. If you move the secondary closer to the primary then it will not be in the optimum location . Even more so if the tube is almost fully collapsed.

Okay then. Thanks for the info.

So, how have other people built there covers for the top frame? 

[Cornelius Varley]

Thin rubber sheet, camping mats.

 

[Ganymede12]

I had an idea for a design for a solar filter in which I put a large sun sheild on the front so that if the telescope moves then the sun won't pass through the sides. I'd also wrap the tube itself as well anyway. Would that work? 

Oh, and what material should I wrap the flexitube part of the OTA in? 

[cjdawson]

Just reading this thread and have a few comments.

1. using the telescope collapsed simply won't work.  The primary mirror defines the characteristics of the scope.  Size = light gathering ability. Curve = Focal length.   The Curve also defines where the secondary mirror needs to be placed,  Well partly.  The secondary mirror also has some say in that.  The secondary mirror is a balancing act, the smaller the secondary mirror, the smaller the obstruction in the light path, a small secondary needs to be further away from the scope than a larger secondary as placing it too close will mean that light will spill around the sides of it and be wasted.

2. Using a Heratige 130p for solar.

I've been thinking of getting one of these scopes for myself and frankly, it's a no go.  The open design means that you've have spillage happening all over the place, adding a shroud will help, but even then, can you trust that it'll never fail?

The end of the scope doesn't look well suited to being able to secure a solar filter.  I'm sure you could make one that would fit, but it would need to be secure. I personally wouldn't trust the open truss type design for solar.

When looking at the sun with a telescope, if the filter fails, you are talking about burning your eyeballs!   I'm not kidding, I've been known to do a demo of unfocused sunlight through my LX-90 onto the palm of someones hand, it never fails to amuse me how quickly they move their hand away.  Are you really willing to risk your eyesight?

Frankley, for solar observing there's nothing wrong with getting a small scope, and I mean tiny, then putting on a solar filter permanently.  It'll be a lot safter.