Posts Made By: Doug Peterson

http://www.sciencedaily.com/releases/2008/04/080407172656.htm

If the La Nina cooling is staving off global warming at least thru this year, then when will the warming pick up again?


http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2008/04/10/eaclimate110.xml

--two DVDs that kept me on the edge of my seat, IMHO much better than "No Country For Old Men" and "There Will Be Blood".

My vote:

The Mist. Unforgettable. You have to see it to know what I mean.

28 Weeks Later. Suprised me expecting a routine sequel. No family should go thru that. Rare combination of human interest and science fictional horror.

Yours?

http://www.bloomberg.com/apps/news?pid=20601087&sid=aU.evtnk6DPo&refer=worldwide

http://www.skeptic.com/eskeptic/08-05-07.html

The chromacor color corrector that turns an achromat into an APO is one of the coolest developments in amateur instruments. However I find the collimation method of futzing around till you get it right cumbersome. I want a deterministic method of collimation on the star test just like collimating an objective, that is, three pairs of push-pull screws at the focuser so adjustments and tweaks can be done live.

1) The only focuser I know that has built in collimation for refractors is the Moonlight. Excellent focusers but screws are on the inside, so you must completely remove the focuser, tweak the collimation screws then replace.

2) Another idea I have involves a collimatable diagonal, but tricky to implement because the chromacorr must come after the mirror.

3) I finally found some inexpensive commerical parts that will allow for tip-tilt at the back of the focuser.

First here is a photo of the ScopeStuff adapter ring meant for use in replacing a Synta/Orion focuser with a GSO dual speed Crayford ($39.00 - #FNCI - Adapter Ring with Hardware for 2" Crayford Focuser); the silver ring is shown between the newtonian base and a standard GSO.

But instead, if you remove your 4" OD Synta/Orion/Celestron refractor focuser body, and install the ring using its three radial screws, you now have a foundation to install the Synta/Orion collimatable 2" Crayford focuser in the Second picture.

http://www.sciencedaily.com/releases/2008/05/080507132855.htm

Two grand for a 7" Mak-Newt Astrograph? I have a used one and they are great. ITE charges upward of 3k, which is more consistent with past prices.


http://www.sciencecenter.net/hutech/intes.htm

The lens figure and internal collimation in the airspaced triplet are excellent, and the color correction is seriously superb. More important the spherical correction is nailed, so that pointlike lesser stars are simply pinholes in the background with no visible rings at 170x, i.e. 50x per inch.

The 2.7" Feathertouch focuser is set here for terrestrial, i.e. a few hundred feet away, distances.

It is about 11-12lbs loaded with rings, diagonal, extension tube (AP 1.75" here), dovetail, will not fit on the Nextstar 5SE fork mount, but perhaps the larger one used on the 6 and 8SE, for that ultimate tabletop bauble when you grow tired of your Questar.