Posts Made By: Dan Huang

July 22, 2003 01:29 AM Forum: Eyepieces

Monocentric Update

Posted By Dan Huang

Just got mine today. Can't wait for it to get dark.

October 13, 2003 01:04 AM Forum: Equipment Talk

AFOV and true field, what is the diff?

Posted By Dan Huang

According to Orion Binocular and Telescope

An eyepiece's apparent field of view is the angular diameter, expressed in degrees (°), of the circle of light that the eye sees. It is analogous to the screen of a television (not the picture seen through it). Eyepiece apparent fields range from narrow (25° - 30°) to extra-wide angle (80° or more). The true field (or real field) of view is the angle of sky seen through the eyepiece when it's attached to the telescope. The true field can be approximated using the formula:

True Field = Apparent Field ÷ Magnification

For example, suppose you have an 8" Schmidt-Cassegrain telescope with a 2000mm focal length, and a 20mm eyepiece with a 50° apparent field. The magnification would be 100 x (2000mm ÷ 20mm). The true field would be 50 ÷ 100, or 0.5° - about the same apparent diameter as the full Moon.


October 24, 2003 10:39 PM Forum: Equipment Talk

Best source for Philips ToUcam Pro

Posted By Dan Huang

Search for ADIRONDACK VIDEO ASTRONOMY on google (click on the first result that pops up). They have TOUCAM PRO II for 129.95

BTW, you were probably looking for the original toucam pro, which was no longer available in the US. Most of the toucam pros floating around are imported from Europe.

November 26, 2003 06:40 PM Forum: Coronado-Lunt-DayStar Solar Filters

More scope scoop on the new Coronado PST!

Posted By Dan Huang

I think I know what I want for my birthday ;-)

And to think sub-angstrom filters just several years ago were outrageous.

February 18, 2004 12:06 AM Forum: Coronado-Lunt-DayStar Solar Filters

PST's

Posted By Dan Huang

I heard the first batch is coming out early March...

February 21, 2004 03:04 AM Forum: Coronado-Lunt-DayStar Solar Filters

The June 8th Venus Transit

Posted By Dan Huang

Yeah, over here in Cali...none of the transit will be available. I weighed the options (weather, airfare, how much of transit I'll actually see)...picked Baltimore, right on the Chesapeake (guarentee no trees or hills or buildings get in the way of the horizon). With the new PST tucked in hand it should be fun...

February 22, 2004 10:47 PM Forum: Digital SLR AstroPhotography

Best Camera for Digi-Scopeing

Posted By Dan Huang

Some of the Canon cameras look really appealing...the G5 or the Powershot S50. Full manual, five megapixel, RAW format...$450 or 350 respectively (similar pricing to the 4500)

April 5, 2004 03:54 PM Forum: Coronado-Lunt-DayStar Solar Filters

Ordered my PST today...

Posted By Dan Huang

According to Coronado, the limited focus travel of the PST may inhibit prime focus astrophotography. It's probably just going to be digicam images from the little scope.

May 5, 2004 02:46 PM Forum: Coronado-Lunt-DayStar Solar Filters

Transit of Venus - eastern US viewing?

Posted By Dan Huang

Alaska?

I'm flying from Sacramento to Baltimore/DC area for the transit. Weather prospects are decent for June...obviously you want to get as far east as you can...sun rises earlier (by a tiny bit, but hey ever minute counts) when you head north (but of course too far north and the weather prospects get grim)...viewing over the Chesapeake Bay guarantees an unobstructed view of the east...

I thought the DC area provided the best compromise of all those factors...and for only $200 for airfare, it was a bargain compared to going to Europe. There's also sighseeing :-)

July 9, 2004 04:20 PM Forum: Equipment Talk

Ever Wonder....???

Posted By Dan Huang

Well I assume the companies have to send their ads months in advance to Sky & Telescope. Maybe back then, it was new... I dunno. Maybe they are advertizing that they are NIB not used.