Spectrum of Samsung S7 phone screen taken with CCDSPEC Spectrometer 31/7/2018

Spectrum of Samsung S7 phone screen taken with CCDSPEC Spectrometer 31/7/2018 – in order from left to right, this represents the peak for blue, green and then red on right. It is similar but not quite the same as the spectrum for the iPhone X when compared to internet sources for the latter (see http://www.displaymate.com/Spectra_41a.html) – I have not checked the iPhone X myself so far.

Andy

 

Mars from the window-sill 30/07/2018

Here is another stab at Mars from the window-sill.

This time the configuration is with an Altair ADC between the X3 barlow and the camera. The extra spacing involved turns the X3 into X5-ish.

I had to “wring its neck” processing-wise to see any detail, but of course you have to bear in mind that it is only a lowly ST-80 through the double glazing!

Still, I fancy that some of the detail is real if you compare it to the Stellarium snapshot, and also with the splendid images here http://spaceweathergallery.com/indiv_upload.php?upload_id=146775&PHPSESSID=dgfiuql6dlb877kjt1fkbn4in4

All the images are rotated to put the S pole at the bottom.

Must get out more!

 

Noctilucent clouds from 2011

Roy Wood was a member of our group who used to love taking pictures of astronomical and weather phenomena with his hand held camera. His fantastic pictures used to put most of us, including me, to shame.

Damian and I recently published photos of noctilucent clouds over alichfiekd this year (2018).

Here are Roy’s photos of similar clouds from 2012 from our club’s archives.

http://www.thornett.net/Rosliston_Archive_2009-11/html/nocilucant_clouds_2-7-11.html

Andy

Dark Star Dob

Oops! I’ve accidentally bought a 10″ Dark Star Dobsonian in need of much TLC for an incredibly good price. The owner was leaving the UK and glad to see it find a good home.

Google suggests that someone not far from RAG already has one of these scopes! Unlike the one in the PDF, this mirror appears to be glued onto a wooden triangle for the mirror cell – eek!

Mirror in need of TLC
Mirror in need of TLC
Dark Star 10" Dobsonian
Dark Star 10″ Dobsonian

Calibrating CCDSPEC spectrograph 29/7/2018 @ 23:00

I tightened the screws on my CCDSPEC to ensure that the camera does not rotate and lose calibration.

Unfortunately, this led to a slight lateral movement in the position of QHY6 camera which changed the calibration of the spectrometer.

Dr Elliott had sent me the calibration process and an Excel spreadsheet to use for the process, which generates the calibration equation I need to use for the calibration file in the MySpectra software.

For the calibration, I used some compact fluorescent light bulbs in my study at home, similar to this one (closed double envelope compact fluorescent lamp):

The following is the spectrum I took 29/7/2018 @ 23:00, using Nebulosity 4 software:

From Wikipedia, I was able to obtain information on the lines seen in a fluorescent light spectrum (https://commons.wikimedia.org/wiki/File:Fluorescent_lighting_spectrum_peaks_labelled.png):

 

I used the above information to identify the lines on my own spectrum. The following is my own spectrum from 29/7/2018 @ 23:00, annotated with the frequencies of the lines from the above table (found by comparison with the typical spectrum above the table) and also with the exact frequencies of the peaks obtained using the function in MySpectra software where you can hover a mouse over the peaks on the spectrum and the measurement shows in a box below the graph.

The two variables are inserted into the calibration file – 0.6283 & 235.05

Below is screenshot from the calibration file with these variables inserted:

 

Download ZIP file of calibration files 29/7/2018 @ 23:00 by clicking on link below:

My calibration using compact fluorescent lights library 290718@2300

Andy