Thanks Nils I checked the filter set. My observations on the points made are below Ulhas ... yellowish ... emit a wide ... you can ... more ... I guess we have...
A little puzzle: The average stepper from a 5.25" floppy drive has a holding torque of 0.9 lbs.in, or in SI: 0.1 Nm (Newton.meter). Gearing it down with 1:1000...
Do you think this will have a significant contribution? Imagine for example a worm connected to the stepper axis and a worm wheel to the scope axis. The...
... No, the motor does not contribute significantly to the inertial loading. Yes, the gearing directly in front of the motor adds a great deal of inertial...
Mel, ... Even if it is just a worm, directly driving the OTA or rocker? I don't think a worm adds much to inertia, since it is proportional to the square of...
... Ok, this is the problem - you're (incorrectly) modeling the worm as if it were a simple cylinder or rod. A worm is many times (100-1000x) more inertial...
This a question to the Aussies on the lists. If I was to make available a number of 10 to 16” slumped plate glass mirror blanks would there be any takers? I...
... Steve, I wasn't referring to that, I saw the rise at the edge in the Foucault data as well. What I was asking about was where the points all fall off the...
Ok, one more post and I'll go back to whatever I was doing before - I've uploaded a screen shot (fringe_profile.gif) of the FringeXP analysis for this mirror,...
Arjan, I guess the holding torque is not necessarily representative of the torque during acceleration. But it would be interesting to see if you can...
Hello Mr.Ukyo Chen I found Your email from August 2005 where you offered to order for those interested in making a L.H. telescope, some 5" L.H. lens sets. Is...
hello Ulhas, ... yellowish ... emit a wide ... you can ... more ... I guess we have the low pressure type lighting -So much the better - it is a bit more...
Dear Peter, The offer is still validate. The sample set is waiting for the last piece of lens, will update my website http://ukyochen.lamost.org once it...
Ukyo Chen
ukyochen888@...
Nov 6, 2006 1:44 am
9984
Mark, I'm sorry to take so long to get back to you on your last message. Here are some commetns. ... I think I see what you mean. The QuickFringe test report...
Steve, thanks for the clarification. I realized after a while that it should indeed be .5 fringe/wave (on the wavefront) for double-pass autocollimation. My...
Mark, ... I have done this many times. It is instructive. You can use averages of different subsets to come to some conclusions about how many interferograms...
For several years I have been trying to compare interferometry analysis with my high resolution Robo Foucault analysis. I have discussed my robo system on the...
I'm not sure what you are looking for but if it is how to compensate for mount fabrication errors see here: http://www.asahi-net.or.jp/~zs3t-tk/ Dale Eason...
Dale, this is really interesting. My testing applications only want to handle errors that are symmetric, so I'm quite encouraged by what you're showing, for a...
Hi All, Maybe someone could give me some feedback on machine work of a sphere. I've polished a couple of different mirror blanks on my machine. It is of an...
Mark, I'm not sure what you are saying. The measured foucault profile is indeed symetric allthough the actual optic is not. Those graphs do not show the...
John: It's tough to make a perfect sphere without having to resort to sub-diameter lap work. To get a little closer try bumping your tool post offset a little ...
I agree, to expect a perfect sphere off a machine in anything over 6" probubly isn't realistic. I know I can't do it. Still, it does most of the work and any...
Hi John, I Machine polished with a net 10" Acculap tool with 1/8" groves on a 14" mirror with 7.5 lb weight (2ounce p/sq.inch) Both speeds about half as wat...
... It is usually the error in the angular seperation between the two alignment stars. i.e. the difference between what your telescope measured and what can be...
... sub-diameter ... little ... way back. ... Hi James, Its nice to see you still lurk in the group. I check in every couple of days to see what's going on....
... tde. ... Hi Peter and thanks, It's interesting your mention of cold water before polishing. I was always under the impression we wanted the pitch to...
If found an interesting surprise in this interferometry analysis of my 16 inch F5 plate glass mirror. http://home.comcast.net/~doeason/ding.jpg Notice the...
