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Posts Made By: Robert Howe

September 19, 2003 08:00 PM Forum: Telescope Making

Double scopes

Posted By Robert Howe

Hi all

One sees binoviewers, which split a single image from a telescope--say a 5 inch refractor--to both eyes. One sees binoculars, which place two tiny telescopes, say 30 or 40 mm each, one to each eye.

Why not take these observations a step farther and make a super-sized binocular, with (say) a pair of 75 or 85 mm refractors, one to each eye, on a common mount? Has anyone designed such a scope and mount assembly? Any experience on this list?

Ciao
Robert Howe

November 14, 2003 12:21 PM Forum: Telescope Making

Collimating refractors

Posted By Robert Howe

Hi,
I am posting this also to Refractor and Televue boards. After having only refractors for some time I bought a used 11 inch Newtonian for deep sky work and set to learn to collimate it. The Menard book says that refractors can be collimated using the Cheshire EP, that in ideal collimation two little donuts will exactly align when the cap is on and the Cheshire is illuminated. So I got curious and guess what, I tried my AP130 and saw the two little donuts, exactly atop one another. I tried my TV85 and got two donuts side by side, and on a TV 102, found three donuts which partially overlapped. The AP is the sharpest telescope I have ever viewed, so I believe this does reflect an accurate assessment of the collimation. However, the Televues have no means to collimate, and their images are pretty darned sharp too. Ought I take this up with Televue, (especially as the 102 is in warranty)? Is this a reliable means of assessing a refractor?

Ciao

Robert Howe

November 14, 2003 12:23 PM Forum: Refractors

Collimating refractors

Posted By Robert Howe

Hi,
I am posting this also to Refractor and Televue boards. After having only refractors for some time I bought a used 11 inch Newtonian for deep sky work and set to learn to collimate it. The Menard book says that refractors can be collimated using the Cheshire EP, that in ideal collimation two little donuts will exactly align when the cap is on and the Cheshire is illuminated. So I got curious and guess what, I tried my AP130 and saw the two little donuts, exactly atop one another. I tried my TV85 and got two donuts side by side, and on a TV 102, found three donuts which partially overlapped. The AP is the sharpest telescope I have ever viewed, so I believe this does reflect an accurate assessment of the collimation. However, the Televues have no means to collimate, and their images are pretty darned sharp too. Ought I take this up with Televue, (especially as the 102 is in warranty)? Is this a reliable means of assessing a refractor?

Ciao

Robert Howe

November 14, 2003 12:24 PM Forum: TeleVue

Collimaitng a Televue refractor

Posted By Robert Howe

Hi,
I am posting this also to Refractor and Telescope making boards. After having only refractors for some time I bought a used 11 inch Newtonian for deep sky work and set to learn to collimate it. The Menard book says that refractors can be collimated using the Cheshire EP, that in ideal collimation two little donuts will exactly align when the cap is on and the Cheshire is illuminated. So I got curious and guess what, I tried my AP130 and saw the two little donuts, exactly atop one another. I tried my TV85 and got two donuts side by side, and on a TV 102, found three donuts which partially overlapped. The AP is the sharpest telescope I have ever viewed, so I believe this does reflect an accurate assessment of the collimation. However, the Televues have no means to collimate, and their images are pretty darned sharp too. Ought I take this up with Televue, (especially as the 102 is in warranty)? Is this a reliable means of assessing a refractor?

Ciao

Robert Howe

November 28, 2003 12:02 PM Forum: Coronado-Lunt-DayStar Solar Filters

MaxScope EP Query

Posted By Robert Howe

Hi all,

I just bought a double-loaded MaxScope 40 from another fellow. First views show very impressive detail of the surface and limb, with prominences galore. But I'm a wee bit disappointed by the size, the Maxscope having only 400 mm FL my shortest FL EP (10 mm) will only give 40x (I usually have Televue 9 and 3-6 mm Nagler EPs but these are with my son this week). Anyway, what is the smallest FL EP that this scope will reasonably take? By the rule of 50x aperture, a 1.5 inch telescope ought to make about 80x, or a 5 mm EP. Has anyone experience with shorter FL EP on this scope?

Clear skies,

Robert Howe

November 28, 2003 04:08 PM Forum: Eyepieces

EP Extender

Posted By Robert Howe

Hi all,

Working with a Borg binocular telescope (ED100) most of my eyepieces, including all of the short FL ones, require placement a half inch above their resting position to come into focus. This creates annoyances in collimating the dual eyepieces. I have been all over Anacortes, but the simple device I seek--a 1.25 inch internally threaded half inch extension tube, to extend the useful length of the EP holders--seems not to exist. Any ideas? I could always get O-rings at the local hardware store but that seems inelegant...

Robert Howe

January 19, 2004 06:22 PM Forum: Deep Sky Observing

Sky Commander problem

Posted By Robert Howe

Hey guys and gals,

For deepspace viewing I have a StarMaster ELT 11 f/5.44 Dob. Installed on it are Sky Commander encoders (USDIgital S2-1000-NT). I bought the computer to use with them but cannot get it to locate accurately; I do not know what the sensitivity of the encoders is, and the USDigital website says it can be from 64-2048 steps/revolution. The Default for the Sky Commander is 4000. Neither the previous owner nor the Sky Engineering Co have answered my emails. Does any one know the correct number?

Many thanks,

Robert Howe

January 21, 2004 11:59 AM Forum: Solar System Observing

Solar Flare Jan 21

Posted By Robert Howe

Hi All

There is an enormous solar flare totay, arising in the 8:00 position as viewed through my MaxScope and with its length being about 30% the diameter of the sun.

Enjoy

Robert

January 21, 2004 12:00 PM Forum: Coronado-Lunt-DayStar Solar Filters

Solar Flare Jan 21 2004

Posted By Robert Howe

Hi All

There is an enormous solar flare today, arising in the 8:00 position as viewed through my MaxScope and with its length being about 30% the diameter of the sun.

Enjoy

Robert

March 20, 2004 09:56 PM Forum: Solar System Observing

Transit of Venus 6/8/4

Posted By Robert Howe

Hey folks,

I am thinking of going to Rome or Tel-Aviv for the Transit of Venus on June 8. The question is, what is the most effective equipment to bring? I've a lovely 130mm refractor and a Losmandy G11, which I think are too much trouble to ship; a TV 85 and a double-loaded Maxscope 30. The TV and Maxscope will go nicely on my Gibraltar mount, but this is not sufficiently stable to do the tiny little Maxscope (400 mm FL) at higher powers (I have been practicing at home), for which I usually use the Losmandy. Suggestions? Anyone got an H-alpha loaded Questar I can borrow? Ideas for a cheaper, reliable tracking mount I can get? Could I mount the HAlpha filters and diagonal on the TV 85 and bring some other telescope for white light viewing?

I am posting this also to the Equipment Talk, Questar and Coronado fora.

Ciao

Robert Howe
Wilbraham, MA