Alan Rogers

Microscopy of diatom in water from canal @ Samuel Barlow @ Alvecote

Alan and Angella took me out for lunch to the Samuel Barlow @ Alvecote – a lovely little pub next to the canal. Before we left, we took a water sample from the canal. The sample proved to be relatively sterile – I suspect due to oil from the multiple boats in local marina.

Andy

On analysing the specimen, this diatom could be seen, viewed through my Zeiss IM35 microscope. I concentrated the specimen first using a centrifuge. Otherwise the following are live unstained views. Colours on the diatom are due to refraction as the organism’s shell is crenulated, refracting light, and has depth making it impossible to focus precisely upon it, worse when magnification increased.

 

Photo x20 objective:

Photo x32 objective:

Video (various objectives):

https://youtu.be/HMyUq8tKuuw

https://youtu.be/QveTzCODOSM

 

Spectroscopy of Vega, Polaris and Deneb with Angella, Alan and Chris Ford 28-29/5/2019

Angela, Alan and Chris Ford came to my house tonight and did a brilliant job calibrating CCDSPEC spectrometer on Equinox Pro 80mm, and hand guiding it to obtain three spectra. Amazing for first ever try!

Andy

The team (Chris Ford, Angella, Alan, Andrew):

Angella controls the imaging software while Alan hand guides the scope:

Calibrating the CCDSPEC (Angella, Alan and Chris):

The image below taken with Samsung S7 phone hand held at eyepiece of CCDSPEC spectrometer shows compact fluorescent bulb with spectrometer slit and cross-hairs of illuminated eyepiece:

Compact fluorescent bulb spectrum:

Compact fluorescent bulb spectrum profile in RSPEC after calibration (after calibration shows angstroms of wavelength rather than pixels on x-axis):

Angella used the following graph to calibrate the spectrum of the compact fluorescent bulb – it shows known wavelengths of specific lines in the length (prepared using data in Wikipedia):

Vega (Angella and Alan) – the profile showing the Vega spectrum compared to that of reference library A0V spectrum shows close match with hydrogen Balmer lines:

Polaris (Angella and Alan) – much fainter and more difficult to obtain high quality spectrum tonight – nevertheless some significant lines can be seen to match on the rather noisy spectrum obtained tonight:

Deneb (Angella and Alan):