Bahtinov Style Focus Masks

[cwlail]

has anyone tried a

Bahtinov Style Focus Masks

and if you have is it worth purchasing one

[themos]

You can make one yourself in one evening.

[steppenwolf]

I have only ever made my own but I can confirm that they work very very well indeed!

[steppenwolf]

I have been asked by Psychobilly to point out that in fact it is not true that I have only ever used my own home made Bahtinov Masks but in fact I have also used two made by Psychobilly himself and supplied to me free of charge. These two also worked very well indeed.

I am grateful to Psychobilly for reminding me of this fact.

[Leegsi]

For how much they cost and the time it would take its probably quicker and esier to buy one: Bahtinov, Photography, Meade items at low prices on eBay.co.uk

[MartinB]

For how much they cost and the time it would take its probably quicker and esier to buy one: Bahtinov, Photography, Meade items at low prices on eBay.co.uk

Depends whether you were the sort of kid who enjoyed playing with Meccano and always made the things shown in the Blue Peter annual using used washing up bottles and sticky back plastic.

[steppenwolf]

Ahh, sticky backed plastic, I use that on my masks to keep the moisture out!

[MartinB]

Ahh, sticky backed plastic, I use that on my masks to keep the moisture out!

There you are Cwlail

[dazza1639]

if you fancy having a go at making your own Bahtinov mask go here (Bahtinov Mask Templates) for a few free templates

Regards

Darren

[Jupiter Martin]

I was just going to add that link ive printed one of and have made the template from cardboard what material would you suggest to make one out off

[steppenwolf]

I just print mine off on ordinary laser printer paper but then affix 'sticky-backed' transparent plastic to both side to seal and strengthen. I then attach the mask to a cardboard collar which is a loose fit on the dewshield/end of the 'scope. Here is one I prepared earlier:-

There was a rather good article in the August 2009 issue of S @ N magazine that revealed all and produced a much smarter one that copyright restrictions won't allow me to display here

[rwg]

I made one last night, but haven't had a chance to test it out yet due to the clouds

This site generates a custom mask to match your scope's diameter and focal length : astrojargon - Bahtinov Focusing Mask Generator: Overview . You need an SVG viewer (like InkScape - Inkscape. Draw Freely.) to view and print the generated file.

I made mine by sticking the printout onto card, but the I might have a try using 'plasticard' as the underlay instead - should be more durable and probably easier to cut. I was thinking of making a dew shield out of this stuff too.

Robin

[michael.h.f.wilkinson]

Thanks for the info, I will make one later today!

[themos]

I used the plastic from a large art-portfolio folder.

[Dave]

Print off a mask from the online Mask Generator.

(A Web browser can open the files, but you may need an A3 printer if scope is 10" or over).

Laminate it, then cut it out.

Just tape over the end of the telescope to focus. Remove.

Job done.

You can now take images that are always in focus.

[sgazer]

I made one using the online generator for a Canon camera lens, only 60mm diameter and it works like a dream!

[Jupiter Martin]

For small scopes I just used a old plastic plate for a 90mm one super job

[Merlin66]

Most if not all the replies so far focus on making one...

To answer the question... yes... they are very good and provide an easy method of getting very accurate focus on any telescope.

Can be used visually and with CCD's.

A great innovation!

Ken

[Jupiter Martin]

Heres one I made out of a plastic party plate took 20mins I guess

[arad85]

And you can get ready made ones from a perspex sheet from here: Stay Focused Bahtinov masks from £9 (Powered by CubeCart) Quite reasonably priced, sturdy and no DIY needed....

[Helen]

They are a great investment of time/or money. I've got a metal one that Peter (Billy) supplied for my ZS66, one from Stay focussed for my Megrez 90, and an Astrozap one for the C8 (I did make myself one for this, spent ages cutting it, only to find I got the secondary mirror hole too small ). All work very well. I'm now going to try a DIY job for the camera lens for wide field.

Helen