16" ATM Project Update 1

chuangyee · Post by **chuangyee** » Sat Jan 24, 2004 11:56 am

We only eyeballed the laser to the center of the primary. Need to at least accurately dot in the primary to get better collimation before I can conclude anything. Planets are really sharp at lower magnifications. above 250x focusing becomes really tricky- almost a balancing act too when standing on a stool. 10" was good but jupiter surface details were much easier with the 16".

Post by **weixing** » Sat Jan 24, 2004 12:22 pm

Hi,
I think magnification greater than 250x will surely be a problem for a 16" scope under Singapore atmospheric conditions. Remember that atmospheric condition will affect more on larger scope than a smaller aperture scope. May be you should try the high magnification in Mersing...

Have a nice day and happy Chinese New Year!

chuangyee · Post by **chuangyee** » Sat Jan 24, 2004 1:09 pm

I don't think its right to say that atmospheric conditions will affect larger scopes more - it should affect all scopes equally. Most of the time it is true that magnification above 250x can be the limit but can still try esp on moon and planets.

http://skyandtelescope.com/howto/scopes ... _505_3.asp
http://skyandtelescope.com/howto/scopes ... _505_5.asp

Post by **weixing** » Sat Jan 24, 2004 2:01 pm

Hi,
I think you get the wrong idea...

I'm not saying that the smaller aperture will out perform a larger aperture scope under unsteady atmospheric condition. What I'm trying to said is that at unsteady atmospheric condition, the effect of unsteady atmospheric condition is more obvious in the larger aperture scope than a smaller aperture scope.

Let me give an example: If under a unsteady atmospheric condition, the smaller scope can only see the Jupiter's Great Red Spot clearly, the larger aperture scope will also see the Jupiter's Great Red Spot clearly and even more details. But due to larger aperture, the atmospherice turbulence will also be more visible in the larger scope. As a result, the smaller aperture scope will generate a more pleasing view than the larger aperture scope, but will not give more detail than the larger scope.

The idea behind this is that a larger scope will gather more light and produce better contrast than the smaller scope. But under unsteady atmospheric condition, the atmospheric turbulence will also be enhance in the same way and give a more unpleasant view than a smaller scope.

Get what I mean...

Have a nice day and happy Chinese New Year!

Guest · Post by **Guest** » Thu Mar 18, 2004 8:54 pm

Thats twice the size of the cassegrain at science center.........

Where do you obtain the optics?

Post by **Airconvent** » Fri Mar 19, 2004 12:19 am

cephas wrote:Thats twice the size of the cassegrain at science center.........

Where do you obtain the optics?

Not exactly. The one at the science centre is also 16".
This "Singastro" project is 16.1", hence can claim to be bigger

The mirrors were purchased from atm manufacturers. sam from harlequinastronomics also supply such parts but building your own scope without any experience is not recommended...

Guest · Post by **Guest** » Fri Mar 19, 2004 10:36 am

Is there going to be a star party for the "opening" of the scope. I am sure a couple of cooped up singaporeans can use some r and r in malaysia.......
Don't you?

ariefm71 · Post by **ariefm71** » Sun Sep 11, 2005 8:23 pm

Hi All
Wow, after a long hiatus, Chuan Yi, Wira and I finally met again last sunday to do some final assembly of the scope. As u can see from the photo below, the scope is more or less done. We are just waiting for the glue that holds the secondary and primary mirror in place to dry. We had wanted to take it out for a spin monday nite; and i guess that explains the heavy rain tonite!!!

Anyway, once first-light is ok (keeping our fingers crossed), we will do some finishing touches like giving it a coat of (black) paint and making a shroud.

cheers
cc

CC, whatever happened to this scope? is it possible for us to borrow for the next mersing trip?

Arief

ps: from the picture, it doesn't look it "finished" yet (i don't see ebony star and teflon on the bearings, truss poles only 6 pieces and a bit undersized, etc), i can voluntarily fix that if we can borrow it for the mersing trip :-)

Post by **Airconvent** » Mon Sep 12, 2005 1:51 am

wah...now that arief mentioned it...I remember it now...heh heh
the scope should still be with a very very busy wira...
hopefully you will be able to borrow it for mersing....will give the mileage the biggest aperture scope in singapore deserves...heh

Post by **acc** » Wed Sep 14, 2005 2:08 am

Sorry missed this thread. Arief, the scope is now with Wira. It would be great if you can put the scope to good use!

cheers
cc