sun filters!!

lads,

Here ive got this into my head after going to my first astronomy clubing meeting....ever....im on the way...well its a start!! ...must say the lads in galway astronomy put on a really amazing night with Dr Peter Gallagher Talk Entitled: “Living with a Star” last monday..excellant!!! so sound out lads ,, ill be back!

But my question is does anyone know anything about sun filters...or pros or cons??? thinking of getting them.....any ideas?/

cheers

You have two options - a professionally manufactured kit, or one you can make yourself. Me? I've made loads of them myself.

The ones you can make come from Baader filter. Youcan buy A4 sheets for about €25. It looks like tinfoil, is crumple resistant, and can be easily cut with scissors to make your own solar filters. You make it to go over the aperture of your scope, not at the eyepiece.

The 'professional' ones include names like Thousand Oaks filters. These are far more expensive. They are basically like a glass cap that goes over the aperture of your scope.

Pro's and cons include durability, cost, portability, and some others like contrast and safety. Obviously, the Thousand Oaks are the way to go if you seekt o do solar observing long-term, or even professionally in any way. The Baader way is inexpensive and can be made in about 30 minutes.

If you want details on how to make your solar filter, I have some here from whence we had the Venus Transit in 2004. I still use the same filters today.

Seanie.

Gee Griffinneil i didnt know you were in the Galway astronomy club or in Galway! I think seanie summed it all up!
I have a `Thousasnd Oaks` sun filter for the 8" if you want to have a look at it! its cool you can look at the sun through it without the scope! Although they are expensive,depending on what size scope you have!

You can pick them up fairly handy on ebay or astrobuysell.com/uk

Matthew

Can you state what scope you intend putting the filter on.

As far as I'm concerned, a solar filter can never be too expensive, remember that its you eyesight you are protection here, one mistake/accident and you are permanently blinded!! there is nothing medical science can do for you if you literally burn a hole through your eye.

So get the best you can, I prefer a glass filter as they are fairly robust and have a long life short of dropping it or cleaning it with a brillow pad :lol:

I have several thousand oaks filters, they give a nice yellow/orange sun at the eyepiece, be warned that some sun filter types give you a blue sun image when looked through, they don't all give you a yellow image.

On the strenght of this thread, I am thinking of going for this filter myself. I was just looking at the website and I am a little confused about what to purchase. I am going for solar filters for my 20x80 binoculars, so is it 80mm\3.15"
101mm\4.00"
2+ Glass
129.00
4000G
that I should be going for? :oops:

Or would you recommend that I go for a solar filter for a telescope like the meade 75etx?

Hi Sean,
If you mean thousand oaks,then you'll want the type 2+ filters, they are their best for visual work.
Needless to say, be very conscious when using these on binoculars, its very easy to look up, then put your arms down, the filter falls off unknowingly to you and then you look up again and then disaster. It's much safer if you use a tripod.

BUT, if I were getting filters for binoculars, thousand oaks are a bit expensive for this, you'd need to get 2 filters at 69$ each, usually you state the diameter of the front end of the binoculars in the order, they must be it a good snug fit, they'll happily do custom jobs like that.

www.thousandoaksoptical.com/solar.html


As for binos VS ETX, 2 eyes are better then one, the stereo effect would be very pronounced, although the ETX would be able to give you a higher magnification.