Bahtinov mask generator

[Fred eric]

Hi

I find your generator very interesting but would propose some improvements:

1. being able to round the corners at each slit end, so that the parasitic spikes will disappear;
2. being able to choose the width of the vertical bar (the one that separates the half circle slits to the quarter inclined slits)
3. the F/S factor can be easily calculated. Its value for +/-20° inclined slits is 27.5*N where N is the telescope aperture. I explain how it is calculated here: https://sahavre.fr/wp/masque-de-bahtinov

Clear sky

Fred

[Harshad RJ]

Hello Fred,

Thanks for the suggestions and sorry for the late reply. Some notes below:

On Thu, May 25, 2023 at 12:35 AM 'Fred eric' via SkEye Discussions + Announcements <sk...@googlegroups.com> wrote:

being able to round the corners at each slit end, so that the parasitic spikes will disappear;

This will be tough but I will try to do it. If I understand correctly, what you are suggesting is this:

Before:

After:

Is that correct?

 

being able to choose the width of the vertical bar (the one that separates the half circle slits to the quarter inclined slits)

Sure, this will be easy.

the F/S factor can be easily calculated. Its value for +/-20° inclined slits is 27.5*N where N is the telescope aperture. I explain how it is calculated here: https://sahavre.fr/wp/masque-de-bahtinov

Thanks for the excellent explanation. I will show the suggested value in the next update.

best,

--

Harshad RJ

[Harshad RJ]

I made a couple of updates to https://skeye.rocks/tools/mask/

• Ability to Pan & Zoom the 3D view of the mask
• Ability to change the size of the partition between the different parts of the mask
• Compute recommended F/S ratio as per Fred's suggestion (25.7 * Aperture)

--

Harshad RJ

[Harshad RJ]

The Bahtinov Mask Generator now has the rounding feature.

Also, I just noticed that I missed copying the group in the previous message (back in 2023), which I include below:

On Fri, Dec 22, 2023 at 10:02 AM Harshad RJ <harsh...@gmail.com> wrote:

Some more updates to the mask generator:

* The UI was re-worked after feedback from CloudyNights forum

* There is a help button now which shows a diagram and more information about the measurements

* The aperture field is pulled out to the top level

* The F/S ratio is now not modifiable. Instead you can modify the slit pitch directly, if you wish to.

* Fixed a bug. The slit pitch was being wrongly calculated to twice its recommended value!

* Improved the design of the Tri-Bahtinov mask. The outer and inner segments are now equally sized.

* Fixed some bugs with the 3D library causing distortions or crashes.

--

Harshad RJ