Today was hot and sunny. The perfect day to ATM a solar filter. I opted for a DIY filter simply because it’s cheap to make. All in all I think I spent only a couple of euro’s on double sided tape. An old member the astronomical society I am a member of gave some Baader AstroSolar ND3 and ND5 material and the rest of the materials used is cardboard from Ikea packaging and pizza boxes that were laying around. You could say the pizza we ate yesterday made me do it.
I used: a pair of scissors, double sided tape, regular packaging tape, a pencil, a hobby knife, measuring tape and the cardboard. With these tools and materials I made an easy solar filter as is described on multiple sites like here or in this Youtube video. There’s different ways to make it but they are all the same concept. Just make sure the solar filter wil NEVER come off and be sure to check the construction before every observing session.
Beware! Use the Baader AstroSolar filter or another commercial product. Looking at the sun through a CD or DVD is possible but the damaging radiation of the sun is not filtered out. You *will* damage your eyes.
I decided to go for the off-axis filter. Reasons for me were the fact that the seeing during the day usually isn’t that good and sizing down from 8″ helps getting good views. More importantly I was afraid to tear a large surface AstroSolar filter more easily than a small one. And now I can make a few more or give the AstroSolar material away since I also only got it for free.
So the hole is now the size of one large coffee mug. The views were better then expected. I had a 3″ refractor once, with a Lunt herschel wedge on it. Those views were fantastic but this filter gives me the same views. I do miss the Baader Solar Continuum filter I sold a while back. The green image is something you have to get used to but the details you can see with such a filter are much, much better! So I might just get me one of those again but only secondhand as they are quite expensive.
For now I am quite happy with this addition to my DIY telescope. I do have to give it a coat of paint. It’s probably going to be gold because I have a can in that colour somewhere. And it will look kinda cool for a solar filter too #geekjoy