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tekkydave

DIY Bahtinov Mask

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Hi,

Decided to have a go at a Bahtinov Mask today. I used the generator at http://astrojargon.net/maskgenerator.aspx to create an image which I printed on a laser printer. This was then taped to a piece of thick black card and the slots carefully cut out using a scalpel. I left some tabs of card around the edge. I then took a strip of black card and joined the ends so it fitted around the end of the scope. The front was then attached via the tabs and it was all taped up with black insulation tape.

No stars out tonight to test it on so had to make do with a distant street light. Not ideal but it shows the principal. Very happy with this simple tool and can't wait to try it out for real.

The mask front cut-out with tabs around the edge

post-28249-0-35702100-1387043494_thumb.j

Assembled

post-28249-0-96936100-1387043514_thumb.j

In focus

post-28249-0-92801300-1387045601.jpg

Out of focus

post-28249-0-04215800-1387045576.jpg

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Lovely finish tekkydave!

Was this your first attempt?  My first one was dreadful. I like your idea of using black card!

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Yep, first attempt. I think the secret is to use a sharp scalpel for the cutting out.

Sent from my Samsung G4S using Tapatalk.

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Hi, I'm just wondering if anyone has tried printing the Bahtinov pattern onto clear actetate sheet using a laser printer? I know the acetate is not exactly an optical flat but perhaps the resulting image would be good enough. I would try it myself but unfortunately don't own a laser printer, I tried on an inkjet with woeful result :)

ChrisH

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After a year of using a home made Bahtinov  mask, one night while imaging I thought I'd try a "Y" mask - after 2 mins with a piece of card and a pair of scissors, I had a working one :) I find them much better and haven't gone back.

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