About Kevin

Cadsas webmaster

Resilvering The BIG Mirror

This morning, Rod and Ted of the CADSAS committee dismantled parts of the Alan Young telescope to remove the big 22.5″ primary mirror and the smaller secondary mirror.

The mirrors will be sent to Orion Optics very soon.

Orion will re-coat both mirrors.  We are hopeful their service will greatly improve the mirrors’ reflectance of light and therefore our imaging results.

Although often still referred to as “silvering”, the Orion recoating does not use silver. The modern and widely accepted Hilux coating, uses aluminium in the mirror coating process.

Come and visit in the Autumn when it’s dark again and see the results.

Contributing to the Citizen Science Project on Variable Stars

Over the last few months, CADSAS has been contributing to this Citizen Science project on variable stars.

We capture images of specific night sky objects, process those images using dark and flat frames and then send them to the project leader Dr Dirk Froebrich of the University of Kent.

The project is studying newly-formed, blue stars. Our target winter objects are currently NGC 2244, NGC2264 and NGC1333. We have submitted 8 images so far.

CADSAS are one of a small number of amateur contributers to this project.

Lunar Images From Our Recent Autumn Skywatch Public Meeting

We held an Autumn Skywatch on 10th October for our members and the general public who wanted to come along. The clouds did not look promising that afternoon, but cleared pretty well by 8pm.

Many of our telescopes were set up outside and a good range of astronomical targets were observed, guided by our more knowledgeable members.

Here are three images captured that night with our big telescope, the Alan Young. They have been reduced in resolution for the web.

Clvius and Tycho

Clavius and Tycho

Archimedes and Plato

Archimedes and Plato

Monte Apenninus and Caucasus

Monte Apenninus and Caucasus

Jupiter and big Moon close approach tonight 23 Feb 16

Our member reports…

Captured this picture tonight at home. My Canon SLR did not want to take it, though I tried. (Could be operator faultiness)

However, the mobile phone camera came up with this below. Jupiter close to the Moon. Very bright and splendid. I hoped to dim the full Moon’s brilliance with a bush. Not sure it worked that well. I’ll get my coat..

Jupiter and Moon conjuction by cell phone

Jupiter and Moon conjuction by cell phone

Digital Photo Magazine Star Field Tutorial

One of our members tried the interesting Photoshop tutorial about star field images, in the March issue of Digital Photo magazine. It’s all about capturing a night sky image in RAW file format and then processing it, so you can use it as background in a finished composition, or just as an astronomy night sky image.

First step was to download the (free) Adobe RAW file plugin for Photoshop, together with their DNG (digital negative converter) to convert the .CR2 files from the Canon camera. Some version juggling and a couple of hours, was needed to make it work with an older version of Photoshop. But it did!

Applying the suggestions from the magazine to a night sky image already taken and already on the laptop, it was encouraging. First stage only, but below is the star field image produced, ready for use in an image composition.

And below the processed image, there is a small section cropped from the BEFORE version of the same image, to the same scale.

AFTER

Processed Star Field Image

Processed Star Field Image

BEFORE

Section of the  same image BEFORE processing

Section of the same image BEFORE processing