Hello... Can anyone tell me what the 75% "cone" or "field" is? I'm not sure I'm grasping it. I require detailed explainations in order to understand things. ...
I can understand your reluctance to stay with this group... after all, you joined yesterday and I approved all of your messages as soon as I saw them and spent...
Hey folks, It kills me to see Ken Hunter struggling and having to sell off his hard fought ATM Gems just to cover medical bills. Is anyone on this list...
Good morning James, I've uploaded the latest k.e. and ronchi images dated 1-29-05. I also reloaded the surface error graphs with the CORRECT titles and dates...
What if you construct a plane through the center of mass of the mirror and bond the silicone pads to the glass in that plane? Then there is NO moment to...
Greetings, In line with recent discussions I've posted a simple drawing on the Groups Home Page for a way to eliminate edge supports and Richard's "always too...
I think I know how I got on this spam list. Has anybody else received this one? My reply is always the same: I am hapy to launder their money, protection of...
A few days ago I was asked if the 26+ inch mirror blank was stress tested. I have tested it before but didn't take any photos. Today I took some photo's of the...
... From: Mark Suchting James New version looks great. Thanks Mark There is some unreliable result on the calculation of mirror to lens space error for +-...
Greetings All, I've been working on a re-write of Doug George's original Ross Null calculation software. I think it is finally ready. What does it do? A)...
I've put up a simple website showing the tip of the IceBerg at: http://www.geocities.com/atm_ken_hunter Was spending too much time answering questions and...
Hello All, Got some question... Is the enhanced coating harder to remove then the regular coating. Will the regular solutions remove it? Is ferris cloride the...
Unfortunately for me, I find myself in a bit of a financial shortcoming. If anyone is SERIOUSLY interested in purchasing a 26+ inch diameter X 1- 5/8 thick...
Just last night I checked the focal length of my new lens. I cradled the lens at one end of a appropriate length 4 X 4 angle iron. I then slid a focusing block...
I have a refractor lens I don't know the exact focal length on, so: What's the easiest way to find the focal length on a lens? What's the best way to find the...
A number of people asked for or hinted at the desirability of an animated version of the zone one challenge to try to capture some of the qualities of an ...
ATM and atm_free, I'm going to make a group response to the many responses I got on the zone one challenge. Thanks for everyone's interest in this. Also,...
Here's another attempt to make sure everyone sees the odd brightness profile I see in my zone one example. I have posted two more graphs, one for zone 1 and ...
Hello everybody ! Does anyone has some good advices and / or links referring to building a good equatorial platform for a Dobsonian telescope ? I`m only ...
I believe I have found a possible source of bias in reading zone one in an 8-zone test of an 18" f/4.5. I have written up my ideas in the following report,...
Greetings All, I've been working on an OSLO model of a Hindle sphere null test for a convex hyperboloid (a some day RC Cass, maybe).. Anyway, If I modeled it...
Hello A friend who just joined our ATM group in Durban, South Africa, has found a new source of CeO (Cerium Oxide). It is very pale almost white in comparison...
IMHO, then new Yahoo look is worse than it was before. So much so that I am immediately dissolving all groups owned, and withdrawing membership from all other...
ATM and atm_free, I put together a report that presents eight examples I have collected of cases where Foucault and interferometry don't agree. The heart of...
Mike, I have been doing similar simulations, although I'm not trying to follow Linfoot. I have been using an 10" f/5 tested with six zones. I have a manual ...
I think I have found a significant improvement to the usual manual Foucault test that I will call full-slit Foucault (as opposed to slitless) or the inverse...
Arrrrggghhh, science projects! My son, now in 9th grade, has participated in several and it never ceases to amaze me how watered down the judging is. It's...
Steve Koehler has been kind enough to reduce and organize the wavefront profile data from the two examples I gave in my recent report. These data can now be...
FINALLY, my science project is done. I presented it yesterday. I don't want to be mean but compared to some other kids my was excellent. a kid did, which type...
Does anyone know the formula for % illumination at field of view edge. It's the one that Peters & Pike derived. I have found it in two places, but one was...
