Vixen 102M

[bosun21]

I feel more confident with this lens arrangement than the previous one. I'll keep my fingers and toes crossed for a positive outcome 🤞.

[inedible_hulk]

Good luck 🤞 

[wookie1965]

Would this fit my Vixen 102M so I can put a finder scope on. 

The original bracket is like this in the photo thank you for your help. 

[wookie1965]

Well ladies and gentleman the scope is fixed. I am very surprised that the arrows both point the same way on the glass but its working now.

Thank you everyone that has replied and helped really appreciate it.

Paul 

[dweller25]

Result 👍🙂

[PeterStudz]

This is excellent! Although I don’t have the experience here I’ve been following this hoping for a positive outcome. Well done and all the best. 

[wookie1965]

3 hours ago, dweller25 said:

Result 👍🙂

It was you who suggested flipping the mirror over so both arrows point out not the way I would of marked it but there it is, it was the only configuration left. the person who had it before cut  the back off the little cap on the dust cap  and put solar film in so before I got the wedge out I pointed it at the Sun and just looked through all blurred but when I started to focus I could see the spots I was doing a jig all around the garden.

Put the wedge in and the celestron zoom focused I could not believe how good it looked went down to 8mm and was still focused there were a few whoops of joy I must say.

Cannot wait now get a session in the dark.

Edited March 18 by wookie1965

[inedible_hulk]

26 minutes ago, PeterStudz said:

This is excellent! Although I don’t have the experience here I’ve been following this hoping for a positive outcome. Well done and all the best. 

Likewise. I’m really chuffed for you @wookie1965 😊

[Stu]

Excellent news Paul. Images look good! 👍 

[Littleguy80]

So happy for you, Paul. Like a lot of others I was following this thread with my fingers crossed for you. Thank goodness for the SGL experts!

[Peter Drew]

Perfectly reasonable to have the markings pointing outwards as that is the direction they face.  However, the convention is usually to have the arrows facing each other as the apex of both then also determines the radial location.     🙂

[wookie1965]

31 minutes ago, Peter Drew said:

Perfectly reasonable to have the markings pointing outwards as that is the direction they face.  However, the convention is usually to have the arrows facing each other as the apex of both then also determines the radial location.     🙂

It was dweller25 who said try it and I thought someone else may have marked them that way it was worth a try. 

[callisto]

excellent 

[Rob]

Great stuff Paul. Really good to hear!.

[bosun21]

Great news Paul 👍. Hopefully the clouds will clear allowing you to put it through its paces.

[mikeDnight]

On 16/03/2024 at 18:19, wookie1965 said:

I was thinking that worth a try I dont know how the person marked it up, I would have put the arrows pointing together but someone else could have done just what you said point them the same way.

 In a Fraunhoffer it's usual for the front Crown element to be convex on both surfaces, while the rear Flint element has a concave surface facing forward while the rear facing surface looks almost Flat, though it isn't. If the flint is forward you may have spherical aberration.

[wookie1965]

3 minutes ago, mikeDnight said:

 In a Fraunhoffer it's usual for the front Crown element to be convex on both surfaces, while the rear Flint element has a concave surface facing forward while the rear facing surface looks almost Flat, though it isn't. If the flint is forward you may have spherical aberration.

The flint has a flat back and concave front pointing forward the crown to be honest does have two convex surfaces one more so than the other, what flummoxed me was the lens where marked and as most people would do I had the arrows pointing at each other.

Whoever opened it must not be an astronomer as I would think 99.9% would mark them up pointing at each other not both the same way. 

[dweller25]

@wookie1965

Just for clarity here is a diagram of how the lens arrangement should be, with the crown facing the stars…..

[wookie1965]

11 minutes ago, dweller25 said:

@wookie1965

Just for clarity here is a diagram of how the lens arrangement should be, with the crown facing the stars…..

Yes that is what I have now, the flint has 2 pieces of scotch magic tape the third position looks like a piece of tinfoil. 

A devil to keep in place but managed it. 

[dweller25]

5 minutes ago, wookie1965 said:

Yes that is what I have now, the flint has 2 pieces of scotch magic tape the third position looks like a piece of tinfoil. 

A devil to keep in place but managed it. 

Is the crown at the front of the scope, facing incoming light ?

Edited March 18 by dweller25

[wookie1965]

1 minute ago, dweller25 said:

Is the crown at the front of the scope, facing incoming light ?

Yes it is the light will hit the crown first before going into the flint on its way to the focuser. 

[dweller25]

Perfect, enjoy your scope 👍