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Posts Made By: Robert Howe

June 11, 2011 08:36 PM Forum: Home Observatories

temperature and insulation

Posted By Robert Howe

I have a lovely roll-off with a peaked roof and eaves. The maker and original owner fit bits of insulation into the spaces under the eaves and covered the inside with soft and hard insulation. As the building ages and I perform maintenance, I find my self wondering, why try to insulate a roll-off observatory? Isn't the idea of keeping the scopes outdoors being to let them be at ambient temperature?

September 9, 2011 09:30 PM Forum: Digital SLR AstroPhotography

Questar photography

Posted By Robert Howe

Any thoughts on using a Questar for photographing the upcoming annular solar eclipse and Venus transit? I like the portability and detail of a Q, but I can't figure how to have the Canon Rebel camera attached through the eye port and still be able to use the finder function.

September 30, 2011 07:43 PM Forum: ASTRONOMY

Azimith, Transit, Hotel choice

Posted By Robert Howe

Guys, I am a little red-faced to ask this, but I need to know. I am planning to take a couple of telescopes to Kauai to photograph the Venus transit on June 5 2012. Predictions for this location (http://www.transitofvenus.nl/details.html) show solar azimuth at first through fourth contacts of 84, 77, 279 and 290 degrees. This makes no sense to me. Now if first contact is at 84 degrees, ie, 84 degrees down from north, how can the sun move backwards for second contact? And what will be the direction of the sun at fourth contact--20 degrees to the north of west? If so, the end of the transit would not be visible on a south-facing apartment, but would be from a north-facing. Again, this makes no sense.

So I ask, given these data, what directions will I have to face to witness each contact?

Thanks very much

Robert

October 13, 2011 08:13 PM Forum: Astro-Physics

mounting accessories

Posted By Robert Howe

Added a week later...

I found my answer. Larry at Universal Astronomics sells 6, 8 and 10 inch plates that fit the DOVE 15. The six inch is all that I need for the tiny little Tak, one clamp of the DOVE 15 suffices; the 10 serves for the larger scopes.

This case is closed.

RH


Hi Guys

I am getting frustrated by a mounting problem for which there must be a simple answer. My mount is a very reliable AP 900. For years I have put an AP 130 f/8.35 atop an APM 180 f/7 scope (I had an AP f/9 but it is too long for my observatory). The AP was side-by-side with a TeleVue 85, using a lateral sliding Losmandy D plate (photo).

I now wish to put a solar scope or the Televue or a Tak 60, depending upon circumstances, atop the AP130, and to eliminate the lateral sliding bar. I say atop, to minimize the need to re-balance laterally each time I swap off a scope--the solar scope is 12#, the TV is 9, the Tak only 2. With an in-line top-to-bottom system I could simply record the counterweight positions for each telescope configuration and adjust accordingly.

The large apo is held to my AP900 with their 15 inch ribbed plate, 900RP. Atop this is a DOVE15 to which the AP is attached by a 15 inch sliding bar, SB1500 (48 mm width).

I had intended to put another of these atop the AP 130 to tip in the small telescopes, but the Dove15 will not tighten enough to hold the smaller AP sliding bars, SB1000 or SB0800, which are 38 mm wide. Yet the DOVE08 saddle, which matches the SB1000 and SB0800, is too short to go atop the AP 130. There’s no common length of saddles for Losmandy D plates, AP 15 inch sliding bars and AP 7 to 10 inch sliding bars. What a nuisance.

I suppose I could fabricate a top plate for the Ap130 and apply a DOVE 08 to this, or cut some SB1500 sliding bars in half for my small scopes. Anyone have a better suggestion?

Robert Howe

November 27, 2011 02:06 PM Forum: Astro-Physics

Travel with 5 inch apo

Posted By Robert Howe

The May 21 annular eclipse will be in very attractive astronomy country, the southwest USA. I'll be going to Utah alone (or perhaps with a lovely lady) to photograph it. It makes sense to me to bring a substantial refractor to observe the very dark night sky before and after the eclipse. Usually I use my Traveler for travel, but for this small a jaunt (Newark--> Las Vegas non stop) I am contemplating using my AP 130 f/8.35. To avoid shipping or having Southwest Airlines manhandle it in cargo, I am thinking of turning it into a Doubly Gran Turismo by removing the focuser and lens assembly, carrying the latter in my carry on and putting the tube and focuser in my luggage. Heck, I'll only need two changes of clothing. Does any one have any experience, cautions or thoughts on such a practice?

Thanks

Robert

December 26, 2011 03:37 PM Forum: Solar System Observing

Conjunction 12/26/11

Posted By Robert Howe

A nice conjunction to end the astronomical year.

January 8, 2012 09:34 AM Forum: Solar System Observing

Trouble with Coronado/Canon interface

Posted By Robert Howe

I am gearing up for the impending annular eclipse and Venus transit. I find myself unable to connect a Canon EF Rebel camera to my beloved Coronado 60. The Coronado requires use of the diagonal for proper filtration of the sunlight, so one is obliged to use a 1.25 inch camera nosepiece plugged into the Coronado diagonal. When I replace the lens with such a nosepiece for prime focus photography the Coronado does not have adequate in-focus to give a proper image. I got around this by adding the Cemax 2x barlow, with this I can get a focused image, but the sun laps at the edges of the image frame. This is not suitable to use in the field (at the Grand Canyon, yet) and there does not seem to be such a thing as a 1.5 x Barlow.

Ideas?

January 8, 2012 09:36 AM Forum: Digital SLR AstroPhotography

Canon/Coronado interface

Posted By Robert Howe

I am gearing up for the impending annular eclipse and Venus transit. I find myself unable to connect a Canon EF Rebel camera to my beloved Coronado 60. The Coronado requires use of the diagonal for proper filtration of the sunlight, so one is obliged to use a 1.25 inch camera nosepiece plugged into the Coronado diagonal. When I replace the lens with such a nosepiece for prime focus photography the Coronado does not have adequate in-focus to give a proper image. I got around this by adding the Cemax 2x barlow, with this I can get a focused image, but the sun laps at the edges of the image frame. This is not suitable to use in the field (at the Grand Canyon, yet) and there does not seem to be such a thing as a 1.5 x Barlow.

Ideas?

January 8, 2012 09:38 AM Forum: Coronado-Lunt-DayStar Solar Filters

Coronado-Canon interface

Posted By Robert Howe

I am gearing up for the impending annular eclipse and Venus transit. I find myself unable to connect a Canon EF Rebel camera to my beloved Coronado 60, a very fine scope which outperformed a Lunt 60. The Coronado requires use of the diagonal for proper filtration of the sunlight, so one is obliged to use a 1.25 inch camera nosepiece plugged into the Coronado diagonal. When I replace the lens with such a nosepiece for prime focus photography the Coronado does not have adequate in-focus to give a proper image. I got around this by adding the Cemax 2x barlow, with this I can get a focused image, but the sun laps at the edges of the image frame. This is not suitable to use in the field (at the Grand Canyon, yet) and there does not seem to be such a thing as a 1.5 x Barlow.

Ideas?

May 27, 2012 10:01 PM Forum: ASTRONOMY

Upcoming transit

Posted By Robert Howe

Hi all,

For the upcoming Venus transit, I am having trouble determining where in the telescope field the first contact will appear. Transit web sites show illustrations but are these reversed for a telescope, flipped for a diagonal, etc? I will be viewing nearly straight up to the zenith from Waimea, HI, using a Televue 85 and a Coronado 60 each with a Canon DSLR attached. A large website is giving what I think are nonsense data for my location

http://transitofvenus.nl/wp/where-when/local-transit-times/

Cheers

RH