Eyepiece Projection Webcam Imaging

[Holliday]

After seeing the moons surface for the first time tonight and being blown away with the detail I of course want to take pictures of it!

I've played with the idea of using my DSLR but since it's a 400D and has no video capabilities I figure webcam imaging will be the way to go.

So my question is, what would I need to attach a webcam (for instance a SPC900NC) to a EP projection adapter? The other problem being I want to use my TMB 6mm which has a diameter of about 48mm which I believe is too big for normal 1.25" EP projection adapters.

Cheers for any help

[brianb]

what would I need to attach a webcam (for instance a SPC900NC) to a EP projection adapter? The other problem being I want to use my TMB 6mm which has a diameter of about 48mm which I believe is too big for normal 1.25" EP projection adapters.

You can obtain T mount threaded eyepiece adapters in either 1.25" or 2" fittings. Sorry but you're going to have to get a "thin" EP to use with an EP projection adapter.

But I think you're asking the wrong questions. It's much easier to use a barlow and no eyepiece or projection adapter to increase the image scale, solves the problem of the EP being too fat and eliminates the need for 2 extra adapters! In any case you will likely find that a 6mm EP in a projection adapter gives a focal length extension of ~ x8 which is far, far too much.

Try prime focus to start off with, then move up to a 2x barlow.

There's an example of the sort of image scale you can get with a small telescope (110 mm f/7 refractor) and a 2x barlow here: http://www.bbhvig.uklinux.net/Moon/Moon-100522-2015-FLTX2-large.jpg (23 frame mosaic; 1 MB JPEG image)

OK, it's a better camera than a standard webcam, but the difference is not that much!

[Holliday]

Well going with your advice I ordered a T-ring adapter for my Canon 400D for prime focus, sadly it doesn't have live view so I assume focussing and getting an object in view is going to be a pain, alas it wouldn't be fun without a challenge.

[Nermal]

If you do decide to go down the EP projection route there is this one - Hutech Astronomical Products - Borg Telescopes - that has an internal diameter of 54mm so should fit your 6mm EP

[Psychobilly]

Well going with your advice I ordered a T-ring adapter for my Canon 400D for prime focus, sadly it doesn't have live view so I assume focussing and getting an object in view is going to be a pain, alas it wouldn't be fun without a challenge.

If you can use the 400D "tethered" to a laptop or netbook you can review the images as you take them ... use Eos_utils to control the camera or another option is Yoddahs APT app...

Peter...

[Holliday]

If you do decide to go down the EP projection route there is this one - Hutech Astronomical Products - Borg Telescopes - that has an internal diameter of 54mm so should fit your 6mm EP

A cheers mate, will bookmark it in case I try that route in the future.

If you can use the 400D "tethered" to a laptop or netbook you can review the images as you take them ... use Eos_utils to control the camera or another option is Yoddahs APT app...

Peter...

I do have an NC10 and extension cable for my 400D since I was going to use that method when I used to do some fashion shoots but never got round to it. Will deffo give it a shot.

Got my T ring through today. If I was to use a barlow, would you suggest a x2 or x3 for lunar/planetary work, also would a 1.25" barlow produce vignetting and the 2" not?

And the final question, How would I go about attaching the barlow between the scope and camera?

Cheers again

[brantuk]

For focusing you'll find a bhatinov mask is a great accessory - and you can knock one up yourself for next to nothing

[Psychobilly]

With the DSLR's you can use teleconvertors rather than barlows... I use T mount ones but only rarely...

If you do go down the barlow route the you ideally want to go 2" ...

Have you installed the Eos utils on the NC10 - I had to use an external monitor to get it to install but once it has it will run without it...

DPP wont run though...

Peter...

[Cornelius Varley]

Got my T ring through today. If I was to use a barlow, would you suggest a x2 or x3 for lunar/planetary work, also would a 1.25" barlow produce vignetting and the 2" not?

And the final question, How would I go about attaching the barlow between the scope and camera?

You can work out the diameter of the moon,in millimetres, on the camera's sensor by dividing the focal length of the telescope (factoring in any barlow) in millimetres by 110.

This Astro exposure calculator can be used to calculate the size of the moon for afocal and eyepiece projection photography as well as determining an approximate exposure time.

Using a DSLR for planetary photography is difficult especially as the 400D cannot take videos. Also the sensor size makes it unsuitable.

The barlow lens you would attach to the focusser as normal and the t ring would be attached to a nose piece such this 1.25" adapter or directly to a barlow that has a t thread on the barlow barrel such as this one Skywatcher 1.25" 2x barlow

Peter

[Holliday]

With the DSLR's you can use teleconvertors rather than barlows... I use T mount ones but only rarely...

If you do go down the barlow route the you ideally want to go 2" ...

Have you installed the Eos utils on the NC10 - I had to use an external monitor to get it to install but once it has it will run without it...

DPP wont run though...

Peter...

I have a program called DSLR Remote Pro I think, will have to check later.

Why the extender option may I ask? Surely that's then limited to camera use, where as a barlow can be used for astro- photography as well as normal viewing?

[Merlin66]

Holliday,

You mentioned in your first post using a webcam -SPC900.

If you remove the lens on this camera and fit a 1.25" nosepiece, this can be used to give good AVI's of the moon and planets.

[Holliday]

Also took the plunge and got an Microsoft Lifecam HD from amazon for webcam imaging since the Toucam and SPC900NC seem very hard to come by.

Got a tutorial here how to mod it for astro use;

Instructions for Converting Microsoft Lifecam Cinema HD Webcam for Telescope Use -by Gary Honis

For £35 it's worth a punt I suppose!

[Psychobilly]

Have a look what Neil Philps has been doing with a a Microsoft Lifecam HD that I modded for him...

http://stargazerslounge.com/imaging-lunar/103431-dark-moody-lifecam.html

The T mount teleconvertors fit betweeh a 2" Push fit T adaptor and the Camera T adaptor...

Peter...

[Holliday]

Have a look what Neil Philps has been doing with a a Microsoft Lifecam HD that I modded for him...

http://stargazerslounge.com/imaging-lunar/103431-dark-moody-lifecam.html

The T mount teleconvertors fit betweeh a 2" Push fit T adaptor and the Camera T adaptor...

Peter...

Looking good, I definitely want to focus on lunar first off, so that link is encouraging.

Did you mod the cam in the same manner as the chap who did the tutorial I linked?

I did order some stuff off Astroboot to connect it to my scope, probably the wrong stuff but hey!

If i remember correctly, it was a 1.25" EP holder with a lock screw midway with a female T thread one end and male the other. With that I ordered a t-thread to 1.25" nose piece adapter also. So If all is correct I can use this as a normal EP or whack it into a barlow... I think?

[Psychobilly]

Yeah followed the mod scheme...

Peter...

[Holliday]

Probably a silly question but there's a point which you have to de-solder two leads, would I be able to just cut these instead, or would it be a safer bet to buy a cheap soldering iron and do as instructed?

Apologies for all these questions, really appreciate your help so far.

[Psychobilly]

they are the two leads to the AF mechanism.. you should be able to cut them "Carefully" watch you dont damage ayhing else around there... although this become a totally irreversible mod...

There is one other stage to watch step 6 where you try and get the srews out that hold the mount on if your not careful you can damage components on the pcb...

Peter...