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Messages - enmofinwins

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Reflectors Telescopes Forum / Re: Why no more sub f/4 opticians?
« on: February 09, 2018, 10:51:11 AM »
I think the market for large dobs has been shrinking for years. See fewer every year at most star parties as the baby boomers are getting older, switching to smaller scopes and imaging. Also resale on large dobs is horrible in many cases, your going to take a large hit when you decide to down size.

Sure there are still the die hards that are willing to set up, climb ladders, and transport these beasts, but they are becoming a minority. Peak dob was sometime in the late 1990s early 2000s.....

Beginners Forum / Re: Are there any real American telescope makers left?
« on: February 09, 2018, 10:15:50 AM »
Dennis Steele makes scopes and kits under the Dob Stuff label, TD.

General Astronomy & Observing / Re: Top things to obeserve in the sky
« on: February 09, 2018, 10:03:52 AM »
I never had any luck finding M1. Geez, what kind of astronomer am I, if I can't even find the 1st Messier object! M57 the Ring was much easier to find. M76 the Little Dumbbell is near Perseus. Found it by accident one night star hopping from Cassiopeia to Andromeda. M76 wasn't very impressive in my small scope, but it was still pretty cool to find it.

Keep trying, you'll find it, but stick to the clearest Moonless nights when it is on the meridian. And eat your carrots.

« on: February 09, 2018, 08:22:12 AM »
I didn't know that, Chuck! They appeared and then vanished just as quickly after being available for about 3-4 years.

I love the finish on yours! and an excellent set-up!

ATM, Optics and DIY Forum / Re: Building a 4" F15 Dall-Kirkham Cassegrain
« on: February 09, 2018, 06:17:10 AM »
The mirror set that I used in my 6" F20 Tinsley Cass had no documentation. So, I built a wooden test bench, a temporary secondary holder, and used a painter's bucket to balance & tilt the contraption at the Sun. That got me close enough to the spacing to build the permanent holder pictured earlier. The original Tinsley spider has a 3" long cylinder with thumbscrew, and I slid the long bolt back & forth to fine-tune the spacing -- lots of trial & error! The spacing is critical for the best view. I can increase the BFL, but at a cost in sharpness & resolution. Changes greater than +/- 3mm are obvious at the eyepiece.

ATM, Optics and DIY Forum / Re: A SOLID 30 mm F/10 Schmidt Cassegrain
« on: February 08, 2018, 12:46:07 AM »
Very out of the box thinking, pretty cool !I love it !How fast does it cool down ?What Glass is it made off ?Thanks for sharing

Cover them.Phil

ATM, Optics and DIY Forum / Re: Newport Glassworks
« on: February 03, 2018, 08:06:10 AM »
Believe it or not - there are many very successful businesses that don't need more business or business with individuals that want "one off" work. They make a choice as to how they communicate with small users.

I have no idea if this is the case with Newport.

In my own business, I get constantly irritated by companies wanting to advertise my company or wanting to put my business in various trade and business publications. I have never advertised nor have I needed to. I know my customer base well, and have a good relationship with it. New customers come from reputation and word of mouth. I don't advertise to the public and really don't want my phone and inbox full of requests that I don't want to fulfill.

As for Newport - they have always delivered what I have paid for - and I have always called them.

Saw these CNN stories today:

It would seem a good time to follow up with further LP info for the public.

Such discussions about health effects of lighting ignore the problem of light pollution's effects on astronomy, so the CNN articles don't really help very much.

What is needed is to keep both healthy light and unhealthy light away from where it's NOT wanted.

Mounts Questions & Expirience / Re: MyT Carry Case recommendations?
« on: February 02, 2018, 07:33:48 PM »
Yeah I worry about it too, so I take it off and put it in my little tool bag I take with me. Its not such a big deal.

Eyepieces Questions & Recommendations / Re: To Barlow or Not ?
« on: February 02, 2018, 06:34:42 PM »
A Barlow effectively increases the magnification while retaining the eye relief of the original eyepiece focal length. There is absolutely no image degradation attributable to the Barlow.
Increases the magnification and the eye relief, you meant.

Well, I took it out on jupiter. Yup, soft views due to not great collimation... I hope. I have no way of knowing if the mirror is good or a dud, I guess.

I also notice coma even at high magnifications

I've never measured it exactly but, from the moment I open the hatchback door of the car, start dissassembling and finish loading my 20 inch ball scope is about 5 minutes:
The result, once in the back of my small Toyota Matrix hatchback car, with seats folded down looks like this:
In that picture the whole scope is in the car, along with a 4 foot step lader, the ramps and the truss tubes. There would be enough room in the car for a second 20 inch.

I need about the same time when I setup. My scope is permanently mounted on a tracking platform which doubles as the wheeled transport base. My scope does not use digital setting circles (I have to star hop) but it does track. Because it's used for visual only, I never bother to accurately align it on the pole. I just eyball it and the tracking platform does the rest. A tracking platform saves a lot of setup time. As a matter of fact, when I need to move the scope around the observing field because a tree is obstructing the view, for example, I just pull the carry handles out of their base, lift the scope on its wheels, and away I go! I don't even need to turn off the drive platform motors or dissassemble the scope in any way.

When I designed the telescope I deliberatly incorporated features that make setup and take down by one person fast and easy. Things like the transport handles, that retract into the base and the freedom from using any tools whatsoever during setup and take down.

See herefor lots more information on how I setup, take down and transport my 20 inch.

ATM, Optics and DIY Forum / Re: GOTO Dob - ideas being sought
« on: January 31, 2018, 05:42:03 AM »
I help a professor every weekend with making two 8" GoTo Dobs to be used for astrophotography, and he has a very DIY system:

Both axes are driven by 3d-printed gears with several hundred teeth to achieve accuracy within a few arcseconds, and there are smaller, motorized gears to turn the larger ones on both sides. The motorized gears are driven by a Raspberry Pi.

Fancy? No. Simple and cheap? Yes. The entire system costs maybe $100. Furthermore, you can reprogram the Pi for using the Dob on a wedge.

ATM, Optics and DIY Forum / Re: Circle inscribed in a dodecagon
« on: January 31, 2018, 05:36:34 AM »
Have not had time to update this thread (or work on the project) until today. Here's a shot of the tube now with two coats of spar urethane on it. One more to go.
Also made a Gary Seronik style plywood mirror cell for the GSO 8" f/4 mirror I just received.
This was very easy to make (as GS claims it is); we'll see how precisely it allows me to collimate. For this light mirror I think it will provide adequate support (plan is to attach w/silcone); not sure I'd try this approach with anything bigger than an 8" however.

I have a secondary mirror and hardware on order from Randy at Astrosystems. Next steps are to make the front and back trim rings, and the rear plate that will feature three 40mm fans to waft air through that mirror cell.

Then to work on the mount.

Should be done sometime next spring, at the rate I'm going ;-)

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