22.05.2020 Centering collar for the digiscoping camera lens.

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Friday 22nd May overcast with light rain: Removing the camera from the Vortex digiscoping adapter means careful realignment every single time the camera is fixed back on. This is true of all base plate type adapters for cameras without filter threads on the camera lens.

You can't cheat somehow and leave the camera on there permanently. Because you can't [usually] remove the battery to place it in the supplied charger. The slotted, camera base plate completely prevents removal. Unless, of course, you cut away the base plate locally to allow the little battery door to be accessed and opened. That may not leave you enough material to support the camera properly.

It follows that digiscoping is best applied to cameras with a threaded "nose" to their lenses. This would allow instant alignment every single time it was placed on the telescope eyepiece. Without all the "fuss" of re-aligning a base plate type adapter.

Some short zoom, compact, digital cameras do have these filter threads, but by no means all. You may wish to purchase a camera better suited to digiscoping using a threaded lens adapter. Rather than using one of those horrible and hideously clumsy "universal" digiscoping adapters. I bought one of those first and soon gave it up as completely hopeless.

Since I was being forced to remove my own camera, so often, I thought I ought to seriously consider all other alternatives. A new camera would certainly be the most expensive option and was discounted for the moment. I needed a far more affordable idea after my considerable expenditure on the tripod and telescope!

It occurred to me that I could more easily center the camera lens in the PS-100 digiscoping adapter. All I needed was a suitable, tubular collar. One which fitted the outside of camera lens base when it was switched on and the lens protruding as normal.

Meanwhile, the outside of the collar must fit closely, but  not tightly, inside the 37mm, threaded hole in the Vortex adapter's, adjustable, front plate. BTW: A 50mm threaded version of the front plate is still available from some Vortex stockists if that helps with your own particular camera.

By the most amazing coincidence I had some white, PVC, plumping pipe hanging around. This was of exactly the correct size both inside and out. Plastic has the distinct advantage of not cosmetically damaging the camera or the adapter. Metal almost certainly would cause damage! So be warned!

I cut a short length off the pipe and carefully smoothed it inside and out with sandpaper. This was important to avoid any burrs from catching on the delicate camera lens housing. A free fit is far more desirable than tight! If you have a tight fit the camera will probably malfunction or might even be damaged! Consider yourself doubly warned! Don't blame the messenger for your own clumsiness and/or idiocy!

Now I just needed to slacken off the clamping screw at the base of  the front mounting plate of the Vortex PS-100 digiscoping, camera adapter.

Once it was loose enough I slipped the piece of white pipe through the hole in the front plate and over the protruding camera lens base. I had to be very careful that the camera was square to the adapter. Or the centering pipe would be at an angle. It might even do serious damage by causing the lens to jam inside the collar!

Once I was happy with the fit and squareness I could tighten the [front plate] clamping bolt. A far easier method of aligning the camera than judging it by eye.  When I first switched on the camera I was greeted by a slightly offset bright circle on the camera screen. Some more fiddling produced a more centralized image on the camera screen.

It would seem that it would be best to check the camera's focusing screen during final alignment on the telescope. The stub of white pipe still helps a lot. Because it doesn't allow the front plate to move very far. Without it, the front plate slides all over the place. So you can only judge the centering by eye! 

Now it just required that I zoom enough to lose the dark corners [vignetting.]  Then I set the self-timer to 2 seconds and took some pictures through the system. Not an ideal day because it was anything but bright. I was down to 1/80th of a second exposure at f5.6. Which does not protect the images much from movement. Neither the camera itself moving nor the subject. [Both?] The tree shown in the image here was moving in the wind.

The other day, in bright sunshine, I was getting 1/1000 second. Sunshine is usually desirable for a crisp and interesting image. Though overcast skies have the advantage of very even lighting. With much less risk of burnt out highlights and very dark shadows.

The DIY alignment collar provides a bright image circle in the camera screen. So camera alignment can take place even without the telescope. See images above. The red arrow shows sideways misalignment of the image circle. The "up and down" adjustment isn't too bad. The length of the alignment collar affects the diameter of the bright circle you see on the camera screen. 

Some fine adjustment might be possible, or even necessary, on the telescope. This will depend on the fit of your eyepiece adapter clamping ring.

I had fitted the medium thickness, self adhesive, rubber packing material supplied with my Telescope-Service camera adapter. This provided a nice but not tight fit on the Vortex eyepiece rubber. The four, clamping, thumbscrews cause some slight change in alignment on the rubber eyepiece ring when tightened.

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