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Messages - Douglas Preece

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Eyepieces Questions & Recommendations / Re: APM 18mm Ultra Flat Field
« on: February 08, 2018, 10:34:04 PM »
Put the order in on Monday night and here they are at my home here in the state of Ohio, USA.

Way to go Markus!

JeffAttached Thumbnails

JMHO, there's no such thing as a "navigation/finder" either have a well corrected low power eyepiece, or you don't.  Depending on the scope, this may or may not be expensive. A fast dob will chew up and spit out eyepieces that work great in a long fl refractor.

I tried a 15mm Agena EWA (Expanse clone) in my f/4 reflector. Not that great in a fast scope, but ok if I used a 3x barlow with it. The 15mm GSO Superview worked better for me in my f/4 scope.

That is very helpful.

Beginners Forum / Re: Another newbie eyepiece question
« on: February 02, 2018, 03:59:21 PM »
Thanks, Ed, those are great resources. Where I live is right on the border of bright orange and dark orange (changes about a half mile from my house). I'm also a little over an hour from light blue (where there is a state park!). I plan to make the drive out there at some point to do some good darker sky observation.

I really appreciate the other resources (star hopping guide, etc.). I suspect that will come in handy!

I have a ETX90RA with the three legs and have had outstanding results with it. I also have a tripod but seldom use it.

The scope is used on our patio table, which provides a very solid platform. The table is a high model as are the chairs. I move the scope around the table depending on what I want to look at. I also have a very sturdy portable wooden table which can be somewhat portable.

The setup works extremely well for me. The 90mm has limitations, but the grab n go aspect is hard to beat. The scope is kept in a sunroom for easy set up and I can be viewing within five minutes.  With the table, I have a system. I keep a notebook, red flashlight, and binoculars on the table (which is round). On an adjacent chair are my charts and a clipboard with my plan for the night. On a chair to the other side is my eyepiece case (40mm, 26mm, 20mm, 16mm....all Meade Plossels, and a 14mm Paul Rini, plus a 2x shorty barlow).

The straight thru finderscope is difficult, but I have adjusted quite well. I have a short stool which is used to sit on and view thru the finderscope. Objects directly overhead are difficult to find with the finderscope, but not impossible. I have become pretty good at aiming and locating objects without using the finderscope.

The limitations of the ETX are obviously the finderscope, but also the limiting aperature which makes deep sky objects such as galaxies and globular clusters difficult to view other than a "smudge" of light. It is very good for open clusters and doubles, which are the two items I have gravitated to. My environment is very limiting also. My best views are from Polaris to the NE, E, and S. I have no views to the west and SW due to trees. Living in a neighborhood, there is also light pollution.

Last Christmas the opportunity arose for a new scope as a present from my wife. After deliberations, I passed. This scope, with limitations provides me with enormous satisfaction in this hobby.

At some point I will go bigger, perhaps with the new ETX125 model that is being re-introduced. If it has a tabletop feature, that would be a plus.

Ed, all of my reports on the "observation thread" are made with this scope and the tabletop system.


General Astronomy & Observing / Re: Using a finder scope?
« on: January 31, 2018, 12:53:39 AM »
For those who use a lasar pointer, what is the best way to avoud inadvertantly pointing it at an aircraft?
(most aircraft these days fly direct rather than using the airways, whether flying VFR or IFR)
A lot of us pilots have had scary experiences with lasars pointed into our cockpits (hopefully inadvertantly, but just as dangerous as when deliberate)

I simply look before I turn it on. If I see any flashing lights I wait until they have cleared the area, then I turn it on just long enough to push my scope to the object I want to locate then immediately turn it off.

General Astronomy & Observing / Re: Finding Neptune
« on: January 30, 2018, 01:57:40 AM »

I caught the white stripe last year as well. I can't remember which scope it was in though. It was a fairly high power too. It struck me as odd that I could see it in the scope I did. I don't recall seeing the moons though...

Hi CN community again,

I have a son who will soon turn 5. I was planning on introducing him to the wonderful world of astronomy, and thought that it would be a wonderful way to also learn about optics. Does anyone in the community have experience with introducing kids this age to how these things actually work (I mean telelscopes etc.). What resources have you found to be useful for discussion of such topics?Update 2016-04-03:

Since I had the question in the beginning, I started looking as well. The wonderful world of the internet means that someone has thought of these things before and so ideas can spread quickly. Following, I am listing some sites I have found that may be useful for other parents who may do the same: That is to say leisurely and playfully teach optics to kids.

Websites with optics material for kids:

Khanh Academy:
This guy has never disappointed me. Hi is really good in explaining things.

Michael Biezen:
More traditional lectures which I am not sure is too kid friendly but IS cool refresher material for the grown-up kids.

To add some further confusion, Orion lists the limiting magnitude of the xx14i as 15.4. It lists the limiting magnitude of the xx12i at 15.1. Meade lists the limiting magnitude of the 16" Lightbridge at 15.5. These are all so close to me that it really makes little difference. It seems to me that for the money and reach, the best deal is the xx12i. Does the additional aperture of the xx14i and the 16" Meade add more to the observer's experience in any way other than more weight to deal with? I don't know which is why I am asking.

ATM, Optics and DIY Forum / Re: New dedicated topic on wire spiders
« on: January 26, 2018, 07:08:43 AM »
This topic was created to move good info on wire spiders from the hexapod topic where the discussion was off topic.

Asking partly out of nostalgia; partly thinking about scopes that got away.

I have a wonderful 7" Starmaster dob, which has a tube cradle, large side bearings, and its focuser on the *right* side (as you look from the back). It works superbly-- it is simply a matter of placing the scope onto the mount; nothing to watch out for; just "plop-and-drop" into place. It swiftly and confidently moves right into place on the cutouts of the top sides of the rocker box -- and you are good to go!

The focuser location is especially good for me as I am left-eye dominant.

Used to own -- and remember well -- Discovery dobs which had the right-side focuser, too, but almost everything I see advertised these days has a *left*-side focuser, along with tiny bearings (which Discovery also suffered from. though strategically placed felt solved that problem), and the dobs almost all have things to fiddle with just to get the scope in place -- tension bolts, washers to thread, etc. and things to beware of -- hitting encoders, tension bolts askew blocking the lowering of the tube into position, etc.

Wonder why the tube cradle seems to have gone the way of the Dodo... it's great for tweaking the rotation and the scope's balance, though that's rarely needed.  The tube cradle and large bearings mean that there is a large sweet spot for the tube's position and there isn't a need for rebalancing even with 3x Barlow, large eyepiece, and camera in the focuser! Focusing is rock solid, too.

Also, wonder why makers switched the focusers to the left side! While a 10" dob looks tempting, not sure if I could buy a current dob without large bearings and a right-side focuser!

Oh, well! Next, I'll start reminiscing about when we used to walk five miles to school through 2 feet of snow; the Great Red Spot was actually RED; milk was delivered fresh daily in returnable bottles, a 6" scope was considered a LARGE one; Norton's Star Atlas was the cat's' meow (and still is great to look at); and Edmund Scientific made a great adjustable Barlow that one simply pushed the lens up or down in its tube to change the magnification!

Beginners Forum / Re: Can I use a Celestron 5se Nexstar on a Versago II ?
« on: January 26, 2018, 12:45:11 AM »
Dang auto correct!
I found it on Amazon. Looks great and would work on my refractor as well, if I get an extra mounting base.
One more question: I like the versago II and will check out the ES Twilight too. Any other simple, light manual mounts under $200 I should consider?

Having owned both at some point I would say do not buy Versa Go. Lack of slow motion controls was an issue for me. Another advantage of twlight is that you can change the orientation of the arm to suit your needs.

Also, before spending most of your money, it's worth answering, specifically (to yourself, at least, not necessarily to us) what it is exactly you want to do/improve. When I can answer that question, I find my purchases are usually good. When I buy without being able to answer that question, I end up regretting it.

Not a bad idea, but it's necessary to distinguish between imaging and learning to image. When you're starting out, the latter is an unavoidable goal.

Beginners Forum / Re: What is the benefit of joining an Astronomy Club?
« on: January 23, 2018, 05:35:03 PM »
I joined a club a little over two years ago when I retired, mostly for the
purpose of having something interesting to do. I have been a loner in
the hobby since my teenage years so I have my equipment and style
built from my own experience and preferences. I also live at a dark site
so don't need to travel. Having others to talk to inside the hobby is a novelty
for me, same thing as when I joined Cloudy Nights, so hearing or reading
about the experience of others is pretty fascinating to me. That has been
the big pay off for me, just seeing how others do it. One thing I noticed is that
we on Cloudy Nights seem to like to nitpick the minutia while in a club that
meets face to face, the emphasis is more on just having fun. Sometimes the
most important things are easily overlooked or hidden fromnewbies when experienced
observers argue over the details by point and counter-point.

At my club we have a lot of members who can offer hands-on help within their expertize.
No one comes to me for anything involving astrophotography or technology in
general because I know very little but I get lots of requests to help collimate and also how to find things manually.
Those are my strengths and they get pooled with everyone elses strengths. Everyone
learns and everyone has fun. Cloudy Nights really is not that much different.

Light Pollution Topics / Re: Senior home light behind my house
« on: January 23, 2018, 04:31:30 PM »

Is there anything I can do to get that light to stop shining onto our property without having to have an annoying screen or shield two feet in front of me all the time while observing?

The OP can probably reconfigure his tarps for better results. For any kind of semi-permanent tarp, much will depend on what his parents will allow and what the local ordinances are (and those ordinances can be WEIRD!)[/quote]
Take your pick, and take it with you.

Truth is to find your own ways around it, because it is NOT going away.
It IS going to get worse.

Maybe when Augustus begins driving, he can travel to darker sites and enjoy more.[/quote]
Some of us would like to observe now, in our yards, that we pay for, without having to drive in order to observe at all.

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