A mad idea forming

[geppetto]

Just going for the ccd WH

Well, perhaps with the eyepiece adaptor screwed in

so that I can mount the IR filter.

[The Warthog]

Looking good so far. I am sure you can make this work.

[geppetto]

I am sure you can make this work

Gonna give it a dam good try

[GordonCopestake]

if anyone can geppetto can! King of the MDF!

[geppetto]

Just been thinking about how to mount the camera.

I have a visual back thingy from an ETX I think, which takes 1.25" stuff.

I could tap that and mount it on the aluminium bar atop some thin threaded rod.

Then, the nospiece adaptor on the webcam (holding the IR filter) would slot into that ring.

Also, I could put my Cheshire jobby into that for a rough siting of the mirror centre marker.

[The Warthog]

Just been thinking about how to mount the camera.

I have a visual back thingy from an ETX I think, which takes 1.25" stuff.

I could tap that and mount it on the aluminium bar atop some thin threaded rod.

Then, the nospiece adaptor on the webcam (holding the IR filter) would slot into that ring.

Also, I could put my Cheshire jobby into that for a rough siting of the mirror centre marker.

I thought about that last bit, and I don't think it will be all that rough.

I still think you should mount the camera on a ring of the right size, which would eliminate any diffraction issues, but your idea will work, too.

[geppetto]

WH

The size of this Toucam is always going to be the downfall of the mad scope.

Its a fair chunk in the way of the light path relative to the size of the mirror.

Still, with a lot of its casing out of the way, it should still work I reckon.

I'm still wondering about wether I could unsolder one row of pins of the ccd

and lift it so that it is then at 90 degrees to the board.

This would show a very small profile in line with the lightpath but then as

Arthur pointed out, extending the connections to the ccd would cause noise.

Something to think about :?

Re diffraction issues, given the odd shapes of the camera in the light path.

Would it be better to make a circular disc of card or some such to fit on the front

of the camera (with a hole cut for the ccd), the size of which would just cover all

of the camera bits and present an evenly shaped obstruction to the light path

similar to what a secondary mirror does?

[The Warthog]

Re diffraction issues, given the odd shapes of the camera in the light path.

Would it be better to make a circular disc of card or some such to fit on the front

of the camera (with a hole cut for the ccd), the size of which would just cover all

of the camera bits and present an evenly shaped obstruction to the light path

similar to what a secondary mirror does?

I would leave that until you have a working prototype. If I were to start a project like this from scratch, I'd be tempted to use one of the eyepiece cameras that are available, although the resolution may not be all you could want. They are not much more than 1.5" in diameter.

How big is the toucam?

[geppetto]

WH

This Toucam is about 1.5" wide but about 2.5" tall.

I will open it up and have a look inside, I guess I may

be able to loose some of the case to make it less long.

The mirror box is made 8)

[The Warthog]

Then it will give you about a 13% obstruction on a 6" mirror. No worse than some SCTs.

[geppetto]

Ok

A good start in the workshop today.

MDF roughed out and mirror mount sorted.

Aluminium slides nicely in the rebate so next job is to do

some measurements to find where the camera mounting rod

will go relative to the mirror and then the focus bits can go on.

Some piccies of the rough build so far

[geppetto]

IT WORKS :shock: :wav:

Long way to go yet but did a crude setup, hung it on the mount and

pointed it at the castle walls on the hill.

Everything was set up by measurement relative to the mirror centre,

slid the aluminium bar in and out to find focus and up popped a picture 8)

Now I know the focal length, I can cut the bar and make the focus control.

Here's the madscope's first image in daylght so poor contrast....

The beast on the mount...

The whole thing weighs in at just under 3Kg

More to follow

[FLO]

Well done Phil,

Top man

[The Warthog]

FAR FREAKIN' OUT!!!

Great stuff, man. Hope to see some astrophotos soon, eh?

Your finder appears to be a rifle sight? Good use for it, what are its specs?

[GordonCopestake]

Excellent phil looks great! No paint job yet?!?!?

I look forward to reading your first light report

[geppetto]

Thanks guys.... MDF rules

WH

Yep its a gun sight, a mate of mine was throwing it away so

I rescued it.

Its got nice optics and is superb for this job.

It says on the top "Nikko Stirling 4*40 Japan"

By the way, had the board out of the Toucam and it measures

1.5" * 1.75" (a lot smaller than when in its case)

I'm going to mod it to long exposure and will remount it in a small case

so I should gain more from the scopes light path...

When thats done, astro piccies will follow or maybe a moon shot or two

in the meantime....

Thanks for the encouragement WH 8)

[Kaptain Klevtsov]

Excellent job, well done mate. I love it when a plan comes together.

Captain Chaos

[MartinB]

Superb Phil. Well done. One thing you will notice when you get it modded for DSOs is the the wire becomes visible when out of focus. It can make you think the scope isn't collimated. Makes a great focus aid.

[geppetto]

Bit more done today.

Focus control is fitted, looks crude but its a suprisingly smooth slow motion control.

The camera bar is push/pulled by a 6mm threaded rod turned by a plywood wheel.

The spring offers a bit of bias to eliminate any slop in the treaded rod.

This setup gives me 1.75" of focus travel which means the camera will focus on its own

and with a barlow fitted 8)

Also fitted a baffle to the mirror box front to cut down any stray light from the sides.

The mirror box interior will be flocked when all else is complete.

[geppetto]

Just set up to test the focuser live.

Its raining so had to image through a double glazed window (not good)

Lined up on the castle flag (English Heritage) and tweaked the focuser.

Very happy to say that it works very very well. Just the right amount

of slow motion and zero image shift whilst turning the knob.

Its so good, I might sell the design to Meade

Here's a piccy of the flag about 1/3rd of a mile away

[daz]

This is a very interesting project Phil. Once finished, you could sell blueprint designs!!! Ker-ching!

[The Warthog]

That's fabulous, and very quick from conception to prototype, too! Excellent!

[geppetto]

<........very quick from conception to prototype.....>

WH

Must admit, I have a good collection of tools which helps no end.

Also, I'm lucky in that I can pop into the workshop for hours on end

without getting into bother

Roll on some nice skies with the moon up for some serious testing.

[GordonCopestake]

Is that an image there Phil? Not showing up

[geppetto]

Gordon

I pressed the image button instead of the quote button :oops:

Good job I dont work in an MOD missile bunker