Solar observing - how to line up scope

[Sparrow]

Yes I will be using a solar filter (don't fancy setting fire to my eyeballs just yet )

So the question is, with the nights getting shorter I thought I'd turn my attentions to the sun. What I'm unsure of is how to line the scope up to it - obviously I can't use the red dot pointer and the only way I can think of doing it is to roughly aim the scope and look at the shadow it casts and use the shadow to line it up - is there a better/easier way to do it?

[Kaptain Klevtsov]

The minimal shadow method works OK, as does watching for the light passing along the 'scope ring ends where the thumbscrews are. I used to have a square of cardboard to project the shadow onto as the grass wasn't very clear.

The other way is to buy / make a solar finder. This is a U shaped thing about 100mm long which you stick to your 'scope. The front riser has a hole in it and the back riser has a crosshair drawn on it. Once aligned, move the 'scope until the light from the sun hits the crosshairs and you're away.

BTW its the full aperture solar filter on the big end that you're using right? Not the Russian Roulette eyepiece filter.

Kaptain Klevtsov

[Macavity]

Yeah, KK. I found the practicalities of projecting "random" parts of the scope onto my (curved!) stomach a bit hit or miss. For some other sources of inspiration:

http://www.dd1us.de/Downloads/a%20collection%20of%20solar%20finder%20designs%200v4.pdf

For me anyway, just soooooo much easier.

[Sparrow]

Thanks chaps - I like the idea of the pin hole and cross hair method - I feel a bit of DIY construction coming on - Yes I'll be using a full solar filter at the "big end" - I was going to buy the pre-made filter from David Hinds - Celestron UK but it's £55 for my scope (Celestron Nexstar 6SE) - but I notice that in his section of Baader Planetarium products, there is a sheet of AstroSolar material with instructions for £15 so I may get that and make up my own filter.

Macavity - thanks for the excellent link - I'll make one of those to fit in the mount for the red dot finder scope (I like the simplicity of the first one shown so I think mine will be based on that)

[Macavity]

Know what you mean re. solar filters - Each time I look at my credit card statement. (Much as my glass filter seems a "good thing"). By trial and error, I found creating an initial "circular sandwich" of the film between a pair of annular rings of "whatever" worked rather well - And take it from there!

[Sparrow]

Thanks for the tip - I think I'll do what you say. To create a secure hold I think I'll do what I did when I created a Hartmann Mask, which is to make a circle (two this time for the sandwich) larger than the diameter of the scope, and then cut many cuts in to the card up to the circumference of the scope, then fold the small flaps over and attach a strip of card to them to make a collar (if that makes sense) - when I did this for the Hartmann mask it fitted really snug on the scope.

[Casus belli]

Yeah the sun is a surprisingly small target when trying to find it by the hit or miss method.

Many thanks for the links Macavity. I've saved it on my wifes favorates folder under "Hints for birthday prezzies"

[SteelRat]

Didn't get to do any solar viewing last year other than the odd scan with my binoculars, but before that have always just used the shadow of the scope and then a low power ep to start. Will make a finder this year - some of those in the link look like fun. Got to get some new film for my scope first

Cheers

Matthew(SR)

[Vega]

Another way is to use the finderscope (with lens cap off) to cast the suns light on the ground then line up this light with the finderscopes actual shadow on the ground. It lines up the sun perfectly (as long as the finderscope is aligned with the scope). Then immediately put the lens cap back on the finderscope. Only problem is, DONT SPEND TOO LONG DOING IT! as if you allow suns rays to shine through the finderscope too long, you could melt the crosshairs inside. You've been warned.

Matt

[Kaptain Klevtsov]

Just remembered another way. When you're close, take the EP out of the 'scope and look up the back. Where the sun is should be obvious as one side of the inside of the 'scope will be lit up. Obviously this is with solar film over the front.

Kaptain Klevtsov

[beamish]

Just remembered another way. When you're close, take the EP out of the 'scope and look up the back. Where the sun is should be obvious as one side of the inside of the 'scope will be lit up. Obviously this is with solar film over the front.

Kaptain Klevtsov

Now you tell me !