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M33 in Triangulum

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Posts Made By: Thomas Dey

March 15, 2016 04:23 AM Forum: A Day in the Life of the Administrator

Am I stupid? Am I missing something?

Posted By Thomas Dey
Thanx for the chuckle! I can see where the guy is upset but apparently otherwise clueless. For sure, he should jump right on CN; expect they would immediately crash the scammer's account (as would you if it happened here!) PS the Amart rating and history are very reliable indicators for transactions here.

March 20, 2016 01:02 AM Forum: CCD Imaging and Processing/Deep Sky

Leo duo

Posted By Thomas Dey
Wonderful! And nice to know you can pull that quality out of the light pollution. I labored oved those targest decades ago with 2h exposures on TP2415 home-hypered film and got what was good for that era = relatively pathetic! I love galaxies, monochrome most of all. Tom Dey

March 23, 2016 03:50 PM Forum: Beginning Astronomy?

Would this be a good telescope for a beginner?

Posted By Thomas Dey
You can probably get pleasing snapshots of the moon with that combo - but little else. Planets would be way way too small; needs a bigger scope and experience. A great book would be The Backyard Astronomer's Guide by Terence Dickenson. This would answer your question and hundreds more! It's slightly outdated, but the most informative / least intimidating that I have come across. Enjoy the hobby! Tom Dey

March 27, 2016 10:05 PM Forum: CCD Imaging and Processing/Solar System

Jupiter 3/22/2016

Posted By Thomas Dey
Nice! It continues to impress me what quality folks are getting with CCD and digital processing. I did film way back when and it was excruciating.
Tom Dey

March 29, 2016 03:44 AM Forum: Off Topic Discussions

They Cracked It...

Posted By Thomas Dey
I figured they would...with or without apple's help. Despite the common (and sometimes justified) accusations of govt incompetence ... Uncle Sam has most commonly been a decade or two ahead of the civilian techno curve. And one more reason mishandling of class info is SO frowned upon. Ironically, this may put apple in a worse position than if they had played along "just this one time" because it shows that their "unbreakable" lock just took a month to pick --- and now probably a few minutes!

March 29, 2016 11:43 PM Forum: CCD Imaging and Processing/Deep Sky

Leo Duo in color

Posted By Thomas Dey
Nice! I esp like the "little" galaxies in the field too, which 16-bit and processing accommodate. Olden EK TP2415 film either got the arms or the core but impossible both. I think that nearly graphic arts contrast was equiv to 4 bits! Tom

March 31, 2016 02:48 AM Forum: Equipment Talk

short catadioptric once advertised in S&T

Posted By Thomas Dey
I recall being mesmerized by the thing - electric-colored exterior with a rounded glossy brilliant finish and looking like giant ceramic crock pot?! - also think one was offered on Amart Classifieds by someone in Europe about a year ago? It appeared the obstruction was HUGE though so I lost interest. If telescopes were PCs --- this would be a pastel Apple. It apparently never caught on though --- not sure why. Tom

April 2, 2016 11:08 PM Forum: After Dark

Viewing the CRAB PULSAR

Posted By Thomas Dey
Oh well - the weather here has been typical = not cooperating. And especially at this latitude the Crab is speeding toward the sun/daylight. Anyway, the 36 I have the mirrors and all the parts are ordered to build it in as a giant GOTO/Track Dob in the Dome. Advantage of building it also that I will optimize it for permanent installation use and even have a separate focuser board that incorporates the Night Vision with the chopper as close to focal plane as possible. The tracking might also allow me to try to do high-speed radiometry if the looking at it fails. I'm stubborn, so unlikely to give up on this until I knock myself out... Tom Quixote

April 5, 2016 11:22 AM Forum: Equipment Talk

Collimating question about centering the star imag

Posted By Thomas Dey
This scope is a "regular" Newtonian, NOT a Bird Jones, right?! If it's better at some off-center point than at center, and the opposite off-center point is even (4x) worse - than yes, that best point is the optical field center. If this is a Newtonian telescope (main mirror and a folding flat), you tilt the main mirror along that vector toward center until it is cured. BTW, the amount of tilt is given by: T = (0.14 x % x afov / mag), where % is how far out from center to edge best focused dot is found, afov is the eyepiece aparent full field of view (deg), mag is the telescope magnification using that eyepiece, and T is the needed tilt of the primary mirror (deg). In practice, you just fiddle with the knobs until it is cured. This assumes that it is indeed Only a collimation (alignment) problem. The Bird/Jones would be a different beast! Tom Dey

April 6, 2016 11:43 AM Forum: Astro Binoculars

bino-power??

Posted By Thomas Dey
Yes, there are many easy ways; try this one: Grab a clear mm ruler. Aim the binos down at a bright floor and see that bright circle of light behind one eyepiece. Measure its diameter "D." Your mag is 50/D. If the binos are 7x50s, that circle will be 7mm. If they are 30x50s, it will be 1.7mm. I just grabbed my 7x42 binos here and did that. I measure 6mm. 42/6 = 7. This method never fails. The Russians actually make a "pupil scale" instrument that measures that very accurately! Tom

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