British Astronomical Association
Supporting amateur astronomers since 1890

Secondary menu

Main menu

BAA Community Member Pages John Hughes
Image search



Expand image

About this observation
John Hughes
Time of observation
23/02/2019 - 23:04
Observing location
North Essex, UK
William Optics Z61 with flattener
Celestron AVX mount
Canon T3i DSLR
Orion 50mm guide scope
ZWO ASI120mm-s guide camera
ISO 800, 25 x 100 second exposures plus flats, bias and darks
Like This Image

Always enjoy looking at M45 through binoculars and so decided to see if I could capture this with my WO Z61. The image called for 100 second exposures so this required me to guide, something I have never done before. There were a few teething problems at the start but eventually I got down to capturing some images but it became clear that some proper planning would have been beneficial. 

As we approach Spring, M45 isn't ideally placed and it was made worse as throughout the session it sat above street lights! In the end 25 light frames was all I could capture as I am embarrassed to say that my house then conspired against me and got in the way!

All part of a steep learning curve.


rotty's picture

Despite all the odds, you've produced a superb image with nice round stars indicating superb guiding. I'd say you're a good way along that learning curve.

How did you perform the guiding in the end?

Hughsie's picture

Guiding was achieved through PHD2 but the biggest challenge was the guide scope and attaching it to the WO Z61. The guide scope is 50mm and when compared to the Z61 at 60mm it was really important to have the scope balanced. To help with this I upgraded the stock Celestron saddle on my AVX mount to the ADM dual saddle upgrade. 

As the dovetail bar which the WO Z61 attaches to is quite short, balancing on a stock saddle would not have been possible as I needed to push the scope way forward to compensate for the weight on the back. As the ADM dual saddle grips along its length rather than via two bolts I was able to achieve this.

Other than that I spent the day before checking the settings on PHD2 and Astrophotography Tool to make sure all my guide scope apertures, pixel sizes etc were inputted before I committed to the session and made sure the guide scope was in focus with the ZWO ASI120mm attached.

Copyright of all images and other observations submitted to the BAA remains with the owner of the work. Reproduction of the work by third-parties is expressly forbidden without the consent of the copyright holder. For more information, please contact the webmaster.