Appetizing mask

[The Warthog]

OK, OK, it's an apodizing mask. I dont' know why it is so called. Its purpose is to remove the diffraction spikes caused by your spider. I dont' know how it works, either, but I pulled the window screen out of my back door today, and made one. (We're replacing the back door this winter, and we won't have a screen door with the new door in place.) Actually, I don't think you have screen doors in England, do you?

You can get an explanation of how to build one at this site, among many others: http://www.csastro.org/gallery/article4.htm

Below are pictures of the screens, and the completed mask. I suspect the measurements are less critical than they look, but it appears I cut the middle screen a little too large, so I'm going to do it again before I staple the whole thing together. I made the hard parts for this, and the Hartmann mask, out of a box that a sweater came in at Christmas. I think Mrs. Warthog was saving it to give someone a birthday present. Too bad.

[Kaptain Klevtsov]

So the spikes are bad? I thought that they gave the image more kudos.

With the DSLR there are no spikes, but the images are poorer than I would get with a telescope (I hope, or I just wasted some cash).

Captain Chaos (who thinks spikes are nice)

[The Warthog]

Apparently, the spikes make it difficult to see detail on the planets. That is why every time I mention problems seeing detail on the planets in certain places, somebody brings up apodizing masks. So, I finally got it into my thick head to make one. I just hope I can replace the back door now before Mrs. Warthog notices the screen is missing from her screen door... :?

[GazOC]

The funny thing is some refractor imagers make a "fake spider" to get defraction spikes on their pictures for effect.

[OXO]

Gaz,

I intend on doing that very thing mate, going to use some fishing wire to get the diffraction spike's i just like the look of stars with them.

James

[The Warthog]

Yeah, but I'm a visual astronomer. Spikes are just a pain in the vitreous humour.

[OXO]

Yeah true Warthog your right there a pain in the Bottie observing wise.

James

[GazOC]

Gaz,

I intend on doing that very thing mate, going to use some fishing wire to get the diffraction spike's i just like the look of stars with them.

James

Plaedies always looks better that way IMO.

[The Warthog]

Make an apodizing mask, though. It's trippy!

[The Warthog]

Here it is on the scope: