First spectrum of daylight with CCDSPEC Spectrometer

Posted by Andrew Thornett

First spectrum with CCDSPEC Spectrometer “First Light” – taken with cap off and QHY6 camera – no telescope – I just pointed it out of the window yesterday afternoon 19/7/2018. I have compared it to Dr Elliott’s sample daylight spectrum that was included with the device.

I am pleased to see that my daylight spectrum (bottom one of pair in picture below – taken 19/7/2018 and not 20/7/2018 as it says in the caption) is very similar to the sample one (top of pair in picture below).

Andy

I asked Dr Elliott who made the CCDSPEC what the horizontal lines in the spectra above were. His response was:

Hi Andrew

The slit is only 50 microns wide which is thinner than a human hair.

The horizontal lines are dust particles on the slit and don’t actually affect the spectrum as you normally add up all the horizontal rows to produce a 1 dimensional spectrum

It might be worth using an aerosol air cleaner but I wouldn’t touch the slit with anything

Pleased  you got a spectrum

Ken

Drawing of Comet C/2017 S3 in Camelopardalis by Nick Cox 20/7/2018

Posted by Andrew Thornett

Really bright in Camelopardalis. Caught this at x50 at 1am.

https://www.skyandtelescope.com/observing/panstarrs-comet-rocked-by-outburst-now-binocular-bright/

Wonderfully bright and easy . Just put in you details here to get coordinates,

https://www.heavens-above.com/comet.aspx?cid=C%2F2017%20S3&lat=0&lng=0&loc=Unspecified&alt=0&tz=UCT&cul=en

Nicko.

Solar Images in H alpha, Calcium K and Visible

Posted by Peter Hill

Most of my solar images have been taken in visible or H alpha , the Baader CaK filter in conjunction with a Herschel wedge provides a relatively “cheap” way of imaging in CaK.

Images in Visible light give detail of the photosphere , which we can consider as the Suns “surface”, above this is the chromosphere, the upper part of which is viewed in H alpha and mid section can be viewed in Ca K wavelengths. (Not quite this simple as there is some overlap, but broadly works this way) The Cak is sensitive to magnetic fields and the stronger the magnetic filed the brighter the image, this gives more detail of the plages around sunspots and more detail of how magnetic field varies in these areas.

After some time setting up a system to image in all 3 wavelengths a fine clear day arrived on Friday 22nd June and I imaged the sunspots and prominences , then went away, which is why I’ve only just finished processing images.

All images were taken using a mono CCD camera : Imaging Source DMK41, the H alpha images were taken using a Coronado PST, the Visual White light images with a Herschel wedge with a ND.3 filter and Baader continuum filter on the camera, using a Skywatcher Evostar 120 refractor. The Cak images were taken with a Baader Cak filter attached to DMK41 and using a Herschel wedge with either a ND.3 or ND 0.6 filter on Skywatcher  ST102 ( for full disc) and / or Skywatcher Evostar 120. All Images were 600 frame avi’s stacked in AutoStakkert, wavelets tweaked in Registax 6 and final processing in Photoshop CS6. Not having imaged for a while I soon realised that I needed to do some cleaning before the next session as the “dust bunnies”  were more numerous than usual, luckily I was either able to manipulate image to avoid most of them or eliminate them in processing.

I have left the images as mono as features show up better for comparison rather than processing in false colour.

Whole disc in CaK and H alpha, no prominences visible in CaK.

 

 

 

 

 

 

 

 

 

 

 

 

 

Main surface features in Cak in Evostar 120, left to right : faculae, AR2715, AR2713

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Faculae in Halpha x2 barlow

 

 

AR2715 In Cak, Vis,  H alpha (x2 Barlow)

 

 

 

 

 

 

 

 

AR2713 in Cak, Vis , H alpha (x2 Barlow)

 

 

 

 

 

 

 

 

Prominences x2 Barlow

 

 

 

 

 

Moon and Venus 15/07/18

Posted by Peter Hill

Now 2 days old the moon at 11% illumination presented it self in the evening sky at an elevation of approx. 12 degrees at 21:30, easily visible, unlike yesterday when I could only pick it out using binoculars.

Its companion this evening was Venus, easily visible unlike mercury of the previous evening. Didn’t have to travel any further than front lawn for these shots.