... (ok, ... working ... be ... I'm planning to buy Howie Glatter's new barlowed laser collimators. I understand he had a few samples at BFSP and that he is...
7059
Mike Lynch
mlynch53
Sep 3, 2003 3:59 am
Mark: You make (below) the single point I wanted to make in this discussion. All other things being equal (meaning that the mirror has cooled to the ambient...
7058
scopebuilder.1@...
john_the_tel...
Sep 3, 2003 3:11 am
I got rid of my laser and only use techtron tools now. I keep a white light flashlight handy for those rare occasions I have to collimate in the dark. John...
7057
Doug Williams
minbaritm
Sep 3, 2003 2:55 am
I currently have a cheap Orion Lasermate Clone laser collimator (ok, I should have spent the extra bucks to get the true Orion Lasermate). My clone Lasermate...
7056
Neal Galt
nealgalt
Sep 3, 2003 2:41 am
Mark...relative to isolating one quarter of the mirror which may have a better figure. I have an aperture stop that connects to the central bolt, which holds...
7055
Rick
rickbmcl
Sep 3, 2003 12:27 am
I have recently started observing with a Meade ETX70AT and have enjoyed it, but have decided to try something bigger. I saw an ad in astronomy magazine for a...
7054
scopebuilder.1@...
john_the_tel...
Sep 2, 2003 11:26 pm
a filter wont help with the light. You have a few options. 1- have a light shield put on it so the light is forced more downwards. 2-set up a laser to shine on...
7053
domin8it
Sep 2, 2003 9:29 pm
I live in a city, not downtown mind you, but the lights are only a few miles away...and I have a street light about 50-75 yards from my house. While I'm a...
7052
dbartolini2000
Sep 2, 2003 7:51 pm
Thanks everyone for your responses. Dave B. ... mask ... through ... does...
7051
mharveyww1@...
mharveyww1
Sep 2, 2003 6:37 pm
John...in response to your earlier post: The Apodizing mask is quite different from an off-axis aperture mask but, yes, I HAVE tried it with similar groups of...
7050
mharveyww1@...
mharveyww1
Sep 2, 2003 6:31 pm
Hi John... By all means....copy away! :) Mike Harvey [Non-text portions of this message have been removed]...
7049
mbungart
Sep 2, 2003 6:19 pm
Bob, An F4.5 will have much more coma than an f6, and be much more sensitive to collimation. It will have a shorter tube, and thus a bit more compact. An F6...
7048
scopebuilder.1@...
john_the_tel...
Sep 2, 2003 6:14 pm
The difference will be little between these two. The F 4.5 needing higher quailty eyepeices such as naglers to give "sharp to the edge" views, and perhaps a...
7047
usafcajun
Sep 2, 2003 5:47 pm
All, I'm looking for the pro's and con's between say and F6 and an F4.5 mirror in regards to an 8" dob I'm building. I figure this is a good place to get...
7046
mbungart
Sep 2, 2003 5:47 pm
Neal, You make a very good point. This thread is similar to one on my local astro club's Yahoo group, some of which I will paste into this message. In that...
7045
scopebuilder.1@...
john_the_tel...
Sep 2, 2003 5:35 pm
PS, mind if I copy that and upload it as a FAQ file in two of my groups? John Kagey ... ________________________________________________________________ The...
7044
Neal Galt
nealgalt
Sep 2, 2003 4:59 pm
There is also another natural mask going on....the pupil of the eye. I hear very little as to the relationship the pupil has with this thread. Observing with...
7043
scopebuilder.1@...
john_the_tel...
Sep 2, 2003 4:35 pm
Very well put !!! Have you tried this test with the aphodizing masks? Have any comments on them? John Kagey ... ...
7042
mharveyww1@...
mharveyww1
Sep 2, 2003 4:22 pm
By now you already know that your friend was wrong. An off-axis mask DOES reduce the effective aperture...regardless of whether the scope is a reflector or ...
7041
scopebuilder.1@...
john_the_tel...
Sep 2, 2003 7:45 am
the answer to your questions is a resounding yes. John Kagey On Tue, 02 Sep 2003 04:42:59 -0000 "dbartolini2000" ... ...
7040
Bob Bunge
bungerob
Sep 2, 2003 7:19 am
Without a doubt it reduces the aperture of both types of telescopes. The light beams are parallel when they enter the aperture. The short distance travelled...
7039
Jay and Liz
stargazerfamily
Sep 2, 2003 6:05 am
I found that reducing the aperture did increase the detail I could see on Mars at low altitude. It also helped to make sure that Mars wasn't too bright. I've...
7038
Attilla Danko
attilladanko
Sep 2, 2003 5:48 am
There is an interesting notion in science called empiricism, which means that you should try it and find out for yourself. If you dont want to wait for a clear...
7037
dbartolini2000
Sep 2, 2003 4:44 am
BTW, the person who says that it doesn't reduce the effective aperture of a reflector *does* agree that it reduces the effective aperture on a refractor. ... ...
7036
dbartolini2000
Sep 2, 2003 4:41 am
I'm trying to settle a disagreement. Does an off-axis aperture mask effectively reduce the aperture on a reflector, and as a result reduce the resolution? One...
7035
Harry Lewin
hml10463
Sep 2, 2003 3:28 am
Neal, My scope uses a DX-1 focuser. There are 4 allen screws at the base. I am at a bit of a loss to understand how they are supposed to function on...
7034
screamcommunications
screamcommun...
Sep 2, 2003 2:55 am
... southern ... have ... 321x can be a chore to track by hand...You'd probably be happier with the 192x ... lose?) For lunar and planetary viewing, you might...
7033
vhallfusenet
Sep 1, 2003 9:49 pm
... Try http://www.handsonoptics.com/used_equipment.html they usually have a used set in stock for $79.Bought mine there.Make sure it comes with the book....
7032
Peter
peterpekurar
Sep 1, 2003 8:43 pm
I'd go for a barlow next. A 2.5X or 2.8X is always nice to have for planets. I live at 43 degrees N Latitude so 250X is about as much power as Mars will take....
7031
gear5clock
Sep 1, 2003 1:24 pm
Hello everyone, I was outside last night here in southern New England viewing Mars with my 10.1" f4.5 and must say I had great success!! With a 12mm eyepiece...
