I am investigating large dobsonians for a semi-portable club telescope. Since faster scopes are shorter they are more transportable, and increase saftety due...
I'm working on a cell for an 18" f/4.2 mirror that uses 45° whiffletree supports. These should be positioned at the plane of the center of gravity, and not at...
I have been a member before and now I am back, planning to build an 18 inch Dob and of course would like to use the best design for a modern, lightweight and...
Good morning all Brian here from cloudy Montreal. Currently a 12.5" owner, (not really a big dob i realize) but i'm considering the purchase of an older...
I finally had some time to make a simulation of a star affected by seeing, in which I use the "Taylor" hypotesis. Namely I compute wavefront and then I slide...
I see that Night Sky scopes say that they center their edge support whiffletree at 30° from vertical. Contact is at 15° and 45° . Each contact point...
I've had several off-list questions about which values to use in the middle panel of the application that defines the heat exchange properties on the back and...
Here is a nice product that can be purchased at Home Depot for $29.oo dollars. Porta Mate Universal Mobile Base. you can get it in the hardware department....
THere is an excellent thread ongoing on cloudynights.com- on DIY setting circles -for those who may not have been following the tthread it has really...
Come join us at the 7th Annual Shingletown Star party from June 30 - July 7 2008! Located on an unused airstrip at an altitude of 4,000 feet in Northern ...
I would appreciate some advise on what PDA i can look for on e-bay that might possibly come with some type of installed software that converts RA/Dec to Alt/AZ...
Hello everyone, It's been quite some time since I've posted any messages here but I figured I post a link to the online construction photo journal of my ...
About a year after the start of the project, the 1100 mm (43.3") f/4 Cruxis telescope is beginning to look like a real telescope! Here's a small picture of the...
Hi Nils Olof, Browsing through the ATM archives I read that you have performed an experiment some years ago, with red, white and green leds to study the...
It seems that the vast majority of commercial dobsonians have collimation handles that extend past the bottom of the mirror box. Does this mean that the mirror...
A question for Starmaster owners: I was looking at as photo of a Starmaster primary mirror cell, and was interested in the edge support. It was difficult to...
While my friend Bill and I both still enjoy our Tele Vue Genisis SDF APO refractors we decided to go Galaxy hunting with a newly acquired pair of Starmaster...
Hi, I'm new to the group and really trying to gather as much information as I can to decided what telescope to buy. I'm interested in pretty well all facets...
Following two previous posts here is an analysis of the effect of seeing on different apertures. It is often (wrongly) said that larger scopes suffer seeing...
I'm looking for the Robert Wade who fashioned his own powered ground board as shown here: http://www.umich.edu/~lowbrows/reflections/2007/rwade.2.html The...
I can't focus with my Dob using a T-Ring and 2" adapter. I have a low profile focuser but still not enough in travel. I have read that the solution is to move...
Hey group! Thanks to all for the great response to the GoTo/Push-To/Drive thread. Now for another question. The scopes I'm considering in the 10-14.5" size...
Hello Bigdob Group! First of all - Happy New Year to all at Bigdob, and I wish 2008 to be a great year for our astronomy pursuits. I'm in a dilemma. I'm...
Does it matter which direction light passes through a UHC or OIII filter? Filters normally thread UP into an eyepiece, I have a filter slide that the filters...
I was curious if any others had applied the Peltier cooling system (such as seen in http://www.acquerra.com.au/astro/cooling/index.html) to a big dob, and if...
