Saturday, 20 February 2016

Lunar Observations and Photography

Good day to you.  There have been two chances to observe in the last week.  Winter is at last beginning to grit it's teeth and produce the cold, still and perhaps most importantly, clear skies that we can usually expect.  My plans for packing the car up with kit and driving to a dark spot for Monday evening were somewhat scuppered by events in work.  But, I was presented with another chance to get out under a clear sky on Thursday evening.
The moon phase at the moment, is approaching full moon, so, as you can imagine, not ideal conditions for looking out the feint fuzzies.  Nevertheless, it was a clear sky, and not one that I wanted to miss.  I decided that it would be a night for moon observations, and perhaps with a little bit of lunar photography thrown in for good measure.
This sounded like a good plan, and a job for the 150p.  When I got home, I took out the 150p and set it up on the EQ mount, when I thought that I might as well take out the SBT as well.  So, with both scopes out and the last of the late evening cloud disappearing, I made sure the battery on my Canon EOS 1100D was fully charged.  Previous attempts at prime focus photography with the SW 150p have always resulted in me struggling to achieve focus.  I've always had to resort to attached a X2 barlow, at which point, sometimes, the image has been too big for the frame of the camera.  I did a bit of reading up on this on a couple of forums, and I still struggled to understand how people got to achieve focus until I saw a photo that someone had posted showing what parts they used.  It all boiled down to 2 parts.  The T-ring adapter for the camera, which is mandatory.  They, the eyepiece holder that fits into the focuser of the telescope and accommodated the eyepieces you wish to use.  I noticed that in the picture on the forum, the eyepiece hold that was being used was different to the one I had with my own scope, but then I noticed that the unit unscrewed leaving the larger part that fitted into the focuser on the telescope, and then the 1.25" section where you would usually insert the eyepiece.  The internal thread of the larger piece was the reciprocal size of the thread on the T ring adapter.  I could see almost straight away that this would improve the amount of inward travel available to me when everything was mounted together.  With a quick check, I could see that I could achieve perfect prime focus with the camera inserted directly into the scope.  This means that with the 750mm focal length of the SW 150p telescope, I had, in effect, a 750mm lens on the front of my camera.  Now, time to shoot the moon!
There are many great advantages to digital photography, but one of the main advantages for beginners like me is that there is no end to the amount of fiddling with different settings you can do to achieve the results you want.  I started with a guess as to what ISO and exposure time to use.  After all, I was photographing a very bright object in the night sky.  My notes from previous sessions using the iOptron Skytracker to photograph DSOs were quite useless.
During the course of the session, I took quite a few photos with all sorts of different settings.  I've put a selection of them together in the following slide show.

Finally, after copying the evenings photos onto the computer, I selected one and posted it on social media to share with my friends and followers.  I received some feedback from one of my followers which simply said "it is a bit to Bright" spelling mistakes and all.  I could understand what this person was getting that, even if it was a bit blunt.  I know editing of astrophotography pictures is heavily relied on to produce a final image,  All the pictures thus far were as they come from the camera.  I've taken that photo that I shared, and I put it into the free processing program called GIMP 2 for some processing.  I find this quite tricky because I don't know what most of the settings do, but I have managed to pick up a few tips and hints over the last 12 months.  So, finally, I want to show two pictures.  One before processing, and the second after processing.  Remember, they are the same picture shot at 1/2500 shutter speed and ISO 800.

Unprocessed.
Processed