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Posts Made By: John MacDonough

October 28, 2013 01:46 PM Forum: Equipment Talk

servicing a Lomo Astele - need help!

Posted By John MacDonough
Jeremy,

Like you, I can only guess. All the mirror cells I've seen have one set of screws for actually adjusting the collimation and another set for pushing against the tip-tilt plate to "lock" the mirror position and hold collimation. Guessing again, I'd say the set of screws that feel "bottomed out" to you are the locking bolts and the other set is for adjusting collimation by tipping the primary mirror. You'll only be able to tell for sure by getting a drawing of the scope or taking it apart.

November 14, 2013 07:05 PM Forum: Equipment Talk

My favorite beginning scope is back

Posted By John MacDonough
I also posted this information in "Beginning Astronomy?" It's started a pretty good thread there. Jon Isaacs has posted some good additional information.

December 3, 2013 07:51 PM Forum: Mounts

Ioptron IEQ45-Az mount

Posted By John MacDonough
Barry,

I have no direct experience, but a fellow astronomy club member has an IEQ-xx and absolutely loves it. I think he has the IEQ-30. He replaced a Celestron CG-5 GT and says there is no comparison between the two, the I-Optron is that much better. He does some visual, but mostly DSLR photography with a C8 or an small Newtonian or refractor.

December 11, 2013 03:11 PM Forum: Astro Binoculars

Mounting 100mm binoculars on an Equatorial Mount

Posted By John MacDonough
David,

Unless your binoculars have 45 or 90 degree diagonals, then you'll have neck-breaking positions to get into, like George said. That said, if you're willing to put up with that, or can find a way around it, then it's kind of cool to have your binoculars track the sky. One of our club members did his binocular Messier list with just such a set-up. He said it was great to be able to consult a star chart without having to do his star-hopping all over from the beginning each time.

I could swear I've seen some posts here of people making a bracket that allowed them to mount binoculars to a fork mount, like a salvaged LX-90 or LX-200 or CPC mount... You'd still have some contorting to do, but not nearly so much as if you were looking in the SW sky with binoculars on an equatorial mount.

January 8, 2014 10:05 PM Forum: Mounts

Restoring a mounts finish

Posted By John MacDonough
Paul,

Anodizing can be stripped and redone. You could also have the parts powder coated. Even more color choices could be had with paint, but you'd have to select the painter carefully. You wouldn't want them to damage a machined surface when they do their prep work.

April 13, 2014 06:14 PM Forum: Eyepieces

If You Could Buy Only One TeleVue Eyepiece...

Posted By John MacDonough
I keep coming back to my 17mm Nagler and 21mm smoothie plossl.

I really enjoy using TeleVue eyepieces. I keep 4mm - 8mm Radians, 9mm - 22mm Naglers in my travel kit. I also have an almost complete set of smootie plossls in my "home" kit. The two eye pieces above are those I reach for most often, though.

May 19, 2014 12:07 AM Forum: Home Observatories

Spaceship over the 6' dome?

Posted By John MacDonough
Dave, it's unanimous, my kids say your space ship cloud is awesome.

June 12, 2014 08:55 PM Forum: Reflectors

Poll for Smaller Dob Owners

Posted By John MacDonough
"Based on my experience with the refractor and earlier times in the hobby when I stood to observe, not using a chair would be for me a show-stopper."

Based on what you said above, I think you've answered your own question, Mark. For what it's worth, I agree. If I'm sketching, taking notes, or looking at one object for several minutes, I much prefer to have a chair. I always keep a chair next to my scope when I observe. The worst that happens is I move the chair out of the way if I start hopping quickly from object to object.

Keep in mind, with a Dobsonian there will be times when you won't be able to use the chair, no matter how long you want to look, due to eye piece elevation.

August 5, 2014 01:09 PM Forum: Mounts

CGEM-DX & CGEM

Posted By John MacDonough
James,

I have a 6" f/12 that the previous owner mounted on an Orion Atlas. I was surprised how well the Atlas did with such a long scope. That said, breezes were a problem, as was damping time in general if the tripod was bumped. Anoth issue is scope balancing. The effect on balance of changing from a small eye piece (say an ortho) to a large eye piece (say a long focal length Nagler or Panoptic) is huge when you've got a long scope.

I already had a G-11, so the Atlas went up for sale here. The G-11 handles the 6" f/12 quite well, but I wouldn't try to photograph through it.

October 12, 2014 07:10 PM Forum: Beginning Astronomy?

fast scopes and planetary viewing

Posted By John MacDonough
Joe, another, minor, advantage to slower scopes is that classic eye piece designs can work well with them. I've read lots of posts by hard core planetary observers about their orthoscopic and monocentric eye pieces. Some of these eye piece designs have only a few elements and thus are capable of low light loss and scatter which improves resolution of small and low-contrast details.

Somewhat related: one of my favorite eye pieces is an Orion Optiluxe 40mm. It produces wonderful images in my 6" f/12 refractor, but terrible flocks of seagulls in my friend's 12.5" f/4.5 Newtonian (even with a Paracorr).

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