517 replies to this topic

[William Mc]

If someone doesn't take advantange of this opertunuty, i'm buying a water jet, and setting up shop!

[MtnGoat]

Heck, a laser engraver can do fairly thick plastic and I'm sure there's a decent plastic for this kind of thing

[Jerry3672]

Here is one formula from Pavel. I don't read Russian, but you'll see the calculus formula is universal.

Dennis- Do you know how fogiving this is? My 200mm aperture F4 scope worked well with a 6.7 mm horizontal slot, and 21.4 degree angle.

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[Dennis Sakva]

Jerry, the mask is very forgiving to both cut's size and angle between cuts. But the sizes determined by Pavel work really good for CCD chips with 7.4um pixels or close to that (DSLRs).

[John Wunderlin]

It is too bad that no one is making these for sale!
Blueman

Hopefully this isn't bad form... I've requested my status to be changed as a vendor, but I can't wait to share this. I officially unveiled the Spike-a mask at the Iowa Star Party this weekend.

Spike-a Focusing Mask

It took a few weeks to get the manufacturing kinks worked out, legal pieces in place, etc, but we're ready to start selling these now!

[Dennis Sakva]

Did you contact Pavel Bahtinov - the inventor of this? I see no mention of his name on your page.

[jimguy08]

Yes, I too would be interested if Pavel Bahitnov was contacted prior to launching a commercial venture of this sort. He deserves to be mentioned as the originator, yes?

[JAT Observatory]

John,
Unless you talked to Pavel I think what you did was while maybe legally OK was ethically wrong, but that is just my opinion.

This is why people shouldn't post ideas without them being patented. As you can see others will take the idea and make money off of someones else's work. Having said that maybe Pavel really wouldn't mind and maybe even hopes that someone will put his idea to good use. If it was me I would have talked to him first.

As a minimum your post should be moved to the vendors forum.

[John Wunderlin]

Sorry guys- I'm in new territory here. When lawyers are in the mix, things can get complicated. They told us since this was posted in a public area more than 1 year ago, the information is considered public domain. However, I agree that there should be recognition of the original inventor. I will follow up on this to get it corrected.

[Jerry3672]

I don't think I can comment on this due to the Cloudy nights terms of service and disclosure we all signed up for when becoming a member. I have contacted the Mods and explained that I should be listed as a vendor. If the Mods want to move my comments to the vendor forum, then I'm all for it.

The legal stuff is being handled by a patent attorney. So I can't comment on any of those issues.

Now back to the original idea of the thread that Dennis started. Everyone is welcome to make their own mask based off of the design that Dennis has described.

[Dennis Sakva]

I don't think anyone here is questioning the legality of you making the masks available for sale. And yes, anyone can do it. It's just seem fair that you mention inventor's name and probably share some profits with him.

Just in case.
By no way I'm financially associated with Pavel. I know him only as a very knowledgeable person always willing to help.

[Tomvictor]

Let me see if I got it right. Can I use the same mask on my FSQ at f/3.6 - f/5 and f/8?

[John Wunderlin]

I tested the 12" version with an F4.7 XT10 and and F10 LX50-10" - it worked well in both scopes.

[Tomvictor]

Thanks John.

[snowdragonusa]

Dennis,

What did you make your mask out of? $150 ++ is a little steep for me so I am going to make my own.

[Dennis Sakva]

I didn't do it by myself. I ordered one at local shop that specializes on advertisement materials. They sell lots of self gluing films, light boxes, etc. They also offer laser cutting services. The 10" one made of 3mm acrylic cost me around $30 to cut. You can also cut one from thick plastic sheet with x-acto knife, but that's not very easy. Though my friend cut 150mm one without too much trouble (he is very diligent). You can also glue black stripes of paper over the mask instead of cutting them.

[Tomal]

Adam, how do you plan to make this mask ?

[snowdragonusa]

Thanks Dennis for the info. I'll call around to some of our local shops to see if they also offer this service. Otherwise I'll look into making my own out of a sturdy plastic.

[snowdragonusa]

I downloaded the InkScape opensource software Dennis had mentioned and worked my way through how to use it. I finally came up with this design.
I have calls out to various laser cutters in town for quotes. I will most likely go with a black opaque acrylic rather than aluminum unless I can find a place that has the anodized. I don't want to be placing spray painted surfaces next to my optics. My size is for the 12" SCT so the slats are 10mm wide and spaced 10mm. The central obstruction is 10cm and the entire diameter for the full disc is 35cm.

I really like the way it turned out and can't wait to try it out!

I named it the Pavel Mask.. I thought it was a fitting name.

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[snowdragonusa]

I just placed an order with a local company that will cut it out of a 3mm black opaque acrylic for me for $37. I think I will bond a couple of acrylic "hangers" on it so it will not fall off.

[Jerry3672]

Nice Drawing Adam. That looks like it will work just fine.

With your 12" LX200 and a DSI pro you should be able to focus on a Mag 6 or 7 star with no problem.

Keep us posted on how it works.

[mikefulb]

Saw this article the other day and I had to try it out. I went low tech and cut out a mask from some heavy felt-like material I found at a craft store and built a simple wooden frame. Going to try it out tonight!

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[snowdragonusa]

Nice Michael! Let us know how it works. If I wasn't able to find a place here in Denver that could cut my drawing for my I was going to go that very route.

Good luck mate!

[Nocturnal]

I would also like to make mine out of flexible material so I'm curious to read how this works for you!

[snowdragonusa]

I started thining about it a little more and decided to have the shop cut a smaller one for my 80mm scope. I tried just scaling it first and it worked perfectly according to the equation and my particular scopes. I also added a few extra pieces that I can fashion into 'hangers'.

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