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How to Build a Simple Piggyback Telescope Camera Mount

Astronomyhints Astro Equipment


Be Ready For The Next Celestial Event

Don't get caught unprepared when then next great comet comes by.

You can make the simple piggyback camera mount described on this web page for your telescope and get some great astro images of the next comet, or many of your favorite wide-field stellar objects like galaxies and star clusters. If the concept of astrophotography is new to you, check out the introductory book Getting Started: Budget Astrophotography. It will give you the essentials. The accessory described on this page is one of the more basic ways to get into astrophotography.

While commercial piggyback mounts are available, they tend to be specific for some of the popular telescopes. But the build it yourself mount on this page will work with any 35mm camera (SLR's are best) or any digital camera capable of taking time exposures. The mount described on this page clamps around the telescope tube, so can likely be tailored (by selecting the right sized hose clamps) to find almost any telescope. However, check out the tailored mounts if you have a popular telescope design. It'll save you some work and maybe mount easier.

For long exposures, you'll need a telescope with a clock drive. It doesn't need to be a giant telescope. One whose drive could handle the additional weight of a camera is all.





Start with a 2 by 4 (No Kidding)

Piggyback Camera Mount Bottom View

The piggyback camera mount shown above is nothing more than a specially cut piece of 2 by 4. Cut off about a 3 1/2 inch length of 2 by 4, giving a square block.

Using a table saw, radial arm saw, or a circle saw, cut out the center section to a depth suitable for your sized telescope.

It's best to make these cuts with the grain of the wood.

The idea is to have a block that will sit on its side rails with the middle (cut out) area not touching your telescope.



Add a Camera Mounting Screw

Piggyback Mount with Mounting Screw

Using the above illustration as an example, drill a 1/4 inch diameter hole through the center of the block.

Run a 1/4 inch screw through the block and tighten on a nut to hold it securely. This screw will be used to hold your 35mm camera or digital camera.

Be sure the screw is long enough to go through the block, a wing nut, and still have a 1/2 inch or so of threads left to mount to your camera.

Thread on a wing-nut in an upside-down configuration. This wing-nut will be tightened against the bottom of the camera.



Finish Off with a Hose Clamp

Piggyback Camera Mount with Hose Clamp

Go to a hardware store and purchase a hose clamp, shown above, that is long enough to go around your telescope. You can likely use a single clamp to go around a small Maksutov cassegrain or refractor.

If you can't find one long enough because you use a bigger telescope, such as an SCT or Newtonian, you can by two or three and fasten the ends together. Just thread the tongue of one clamp into the screw of another.

Cut the clamp and drill a hole through the ends (or one end of each of your numerous clamps).

Mount the non-tongue ends of the clamp(s) to the wood block with screws. Now you can run the clamp around your telescope and tighten the hose-clamp screw whenever you want to take star photographs.



The Piggyback Camera Mount Fastened to Telescope

Piggyback Camera Mount on Telescope

Above is an image of my piggyback mount on my 6 inch f/5 Newonian telescope.

You can see the hose clamp band going around the telescope tube, securely holding the specially cut 2 by 4.

The 35mm camera camera is turned several times onto the protruding screw, and then the inverted wing-nut is tightened against the bottom of the camera, allowing me to align the camera lens with the telescope.

This telescope doesn't have electronic controls in the RA and Declination axes. It uses manual screw controls.

To get the best pictures, I use a reticle eyepiece and defocus on a moderate to bright star in the field near my object of choice (or the center of a comet). If a guide star is bright enough, defocusing it slightly lets it better illuminate the reticle lines.

If I need to make a tracking adjustment with the manual controls, I cap the lens of the shutter-locked camera while I make a pointing adjustment, then uncap the lens when finished. This ensures that any vibrations I cause or mistakes I make in adjusting do not affect my photograph.





And Finally, the Proof

Hale Bopp Time Exposure

Above you see an image of Hale Bopp that was taken with the camera and 135mm telephoto lens shown in the previous picture. I had a different telescope then, but the setup was the same.

How long an exposure is necessary? For comets not that much. 5 minutes will do wonders.

For some of your favorite star objects you may need to go up to 15 or 20 minutes.

This Hale Bopp image is also shown on the 2 Inch Photography page of this site.



Personal Notes

Obviously, to make use of this simple mount you will need a clock driven telescope on an equatorial mount. Almost any will do, though if you use 35mm camera equipment as I do, you may not be able to use a small telescope because of the weight of the camera.

For example, I'm not sure my ETX 90M mount would handle the weight of a 35mm camera and telephoto lens.

But any telescope of 5 inch diameter or bigger will likely have a beefy enough mount to do the job. You need the equatorial mount for several minute time exposures because such exposures on a computerized altazimuth mount would lead to a rotating field of view. A telescope much like the one I use is the Celestron Omni XLT 150mm Telescope Newtonian Reflector 31057. It is large enough to handle the weight of the camera, and large enough in aperture to be able to find adequate guide stars near your targets of interest.

If you want to go digital, be sure you choose a camera than can do time exposers of at least a few minutes.

Once the camera is attached to the telescope, the procedure I use is as follows:

  • Cap the camera lens.

  • Set lens for infinite focus, open aperture.

  • Set shutter on B (bulb) setting.

  • Lock shutter open. Some cameras, like my Exa and Zenit allow this. For others, use a shutter cable with lock.

  • Get the closest guide star in the telescope view.

  • Defocus telescope to let guide star illuminate reticle, then center.

  • Uncap the lens.

  • If I see a guiding adjustment is necessary, I cap the lens, make the adjustment, then uncap the lens.