26 inch Cassegrain Telescope

chanlunlun

Dear Star Lovers,

After more than 2years of struggling, the 26 inch telescope is officially declared completedtoday, on the day of annual Open Day of our school.

The whole telescopewill be displayed on the roof of Queen’s College on Saturday (30 Jan 2016) andyou are cordially invited to come and have a glance and offer comments on this bigtelescope. According to weather forecast the weather will be fine on Saturday.

At its Cassegrainfocus the telescope offers a focal length of 260 inches at f/10. The telescopeis very long, has a length of about 11 feet, which makes it an impossibilityfor a portable instrument. It will stay forever on roof of QC to promoteastronomy among students, and any persons who are interested.

The total weight ofthe instrument is over 100 kg, the giant weight is a must for its stability atour roof, since our school is in constant vibration originating from the next doorMTR tunnels.

Below gives a brieffinal technical specification of this newly finished telescope:-

Aperture :- 26 inches

Type :- NaysmithCassegrain

Zenith eyepiece height:- about 5 feet, a junior form student’s height.

Secondary mirrordiameter :- 10 inches.

Secondary blockage :-38%, a little bit high. ( C8 is 33%)

Mounting :- alt-azmmount with ServoCAT GOTO and tracking + Argo Navis navigator.

Total weight :- >100 kg.

Why we make it? :- toexperiment if we can see DSO at center of city.

Our student are ofcourse very pleased with what they have accomplished. Please come and share theenjoyment with us.

Best regards

Chan Yuk Lun

30 January 2016