Quick links to various main topics in my blog

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Somebody who connected one with ScopeTronix adapters
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DrGoon

The eyepieces of the 'scope happen to be about the same diameter as an iSight body so I've bodged a sleeve to hold them close together (out of an empty spice container and a pair of jubilee clips).

This is called 'eyepiece projection'. If the iSight's lens was removable, then I could dispense with the 'scope eyepiece and do prime focus photography instead.

The bodge works OK with the 25mm eyepiece, because it has a long shank that the sleeve slips over quite nicely and the exit pupil is about 15mm diameter so it's easy to line up with the iSight's field of view.

However, the magnification of the 25mm is only x48 so the image itself is very small and only covers a dozen or so pixels on the CCD. OK for the moon, but pants for planetary work.

It was exceptionally good seeing last night, so I tried my 12.5mm and 6mm eyepieces for fun - even though they're shorter and the sleeve bodge is less precise and more wobbly. Their exit pupils are smaller by comparison - less than 10mm - so it's more difficult to get the eyepiece and the iSight axes co-linear.

The image was taken through the 6mm (x200) by starting a recording and then wiggling the bodge around until Saturn showed up on screen, at which point I tried to hold the whole thing as steady as possible to capture a few frames (most of the 40MB file is blank, or has a very blurry Saturn whizzing across from one side to the other).

Oh, and the equatorial drive on the scope is very sloppy and therefore useless - so I'm also pulling on the end of the tube to counter the Earth's rotation.

And it was bitterly cold. And I was being attacked by a herd of mad yaks.

I'm going to track down a Philips ToUCam 840K (sadly no longer made) because they're definitely more suited to this kind of work - very sensitive CCDs, their lens is removable and there are T-adaptors that screw in to allow you to do prime focus.

I did some image stacking of exposures of the Moon a while ago, which were OK but I really need to sort my equipment out if I'm going to have a proper stab at this.

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simon

On the other hand, it does movies for as long as there's room on the SD card, so with 1GB, I can do around an hour of shooting, so something ought to pass by the eyepiece eventually if I hold it in roughly the right place.

Apparently the new Philips SPC900NC uses the same sensor as the older ToUCam. Problem is that the thread is deeper inside the camera, so new mounts are needed:

Analysis of the camera from an astrocam perspective.

I intend to look into this bracket that Nikon makes for my new P1 camera. If it can be mated to a Meade Plossl, it'll rock. Hopefully I can find a local camera dealer that will let me look at the thing to determine suitability.

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DrGoon

Thanks for the pointer to the 900NC review - I'm surprised Philips would come up with something so unsuitable for mounting to a scope given that they must know how many people fell in love with the 840K. OK, astrophotography's a niche but still...

I've got a Kodak DX6490, and it too takes movies for as long as there's space on the card (512MB in my case, so about half an hour). However, my brief experience with the iSight is telling me that more, shorter movies are better than one long one - certainly when it comes to extracting the good frames for image stacking.

I've now found a place that allegedly has 840Ks in stock, so the credit card is twitching.
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simon

http://www.trutek-uk.com/toucam/toucam_pro.html

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simon

As I mentioned I just got a new camera - not for astronomy, just because I found that my Dimage 5 was too large to be at hand when I wanted to take a picture. I got one of the Nikon P1 wifi equipped cameras because the price was great (around $300) but other than the novelty thing I doubt I'll use the wifi much.

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DrGoon