As I have recently written, I have been toying around with taking pictures with my Canon DSLR camera using the an inexpensive telescope as my primary lens. My first attempt was a bit disappointing but I did learn a lot, which is a lesson of what not to do… However, my second night images are dramatically improved from the first in my humble opinion.
So, what a difference 24 hours can make. In both images, you can clearly see shadows caste from mountains and craters, however the focus in the second nights image is in better focus. The exposure and contract are better in the second nights image and most importantly and interface between the moon and darkness of space is sharp and well defined.
The First Night
The first night of imaging resulting in a full frame image which was a bit blurry and unimpressive. This images was taken using a 700 mm National Geographic entry level telescope with 2X Barlow Lens connected to a Canon EOS Rebol XS Camera connected directly using a T-ring Adapter. Due to the precarious nature of the camera attachment I opted to use a dual tripod setup to stabilize my camera and keep in secure from falls.
The 700mm telescope is equivalent to an 1120 mm when connected to my camera and the use a 2X Barlox brings us dramatically closer. The telescope was mounted on a lightweight tripod with height or roughly 40 inches. When everything was connected, I was attempting to compose and manually focus a camera with at a moving object with a relative local length of 2240 mm while manually manipulating two camera tripods. This was compounded by the camera eye piece being roughly 18 inches off the ground an my height being over six foot.
The final results of my first lunar photographs where large blurry images that did not really do anything for me. However, I did something very wise in hindsight. I set a benchmark and the imaging threshold was rather low.
The Second Nights
So, why the difference between the two nights photography. The answer is undoubtedly user error on my part. Although I am using inexpensive equipment, the user error in my first night was very high. There was no way I was going to be able to get a decent image with the technique I was using on the first night. In order to resolve this problem I made two essential changes.
The first item on my list was to remove the Barlow lens. In my imaging system, the system contained the moon the the atmosphere, primary lens, 2X Barlow lens, eye piece lens and then my eye, which is contorted below knee level. I know that the atmosphere can be an issue, however both nights where cloud free and there is nothing I can do about that atmosphere. The primary lens is from an inexpensive telescope but appears to be constructed from glass. However, the 2X Barlow lens is a weak link.
This 2X Barlow lens came included in a Kit from National Geographic. The entire kit retails for just over 100 dollars and includes the telescope, trip and trip head along with two eye pieces and this 2X Barlow lens. I do not want to destroy the good people at National Geographic, however I am pretty sure the protective covers for the 2X Barlow lens are of higher quality. You know it is quality item when there is no manufacturer label and simply a sticker to tell you the devices function.
Removing the 2X Barlow lens made an improvement in three distinct ways. The first is that the low quality lens does not introduce any noise into the system simply because it is inline with the light. Secondly, the 2X magnification also magnifies any errors. I suspect that the blue hue seen in my first image was caused by the low quality lens focusing the blue and yellow light at different distances.
The final benefit to removing this lens is that it bought me time. The moon no longer filled my viewfinder. This reduction in magnification allowed me to take several images before the earth rotated the moon outside of the view finder. This time allowed for better focus, exposure, etc…
The second improvement I made on the second night was to address my own limitations. On the first night, I was manually focusing while moving and adjust tripods. The view finder of the camera was well below my waist. This was just an uncomfortable position to be in and the time crunch was daunting.
For the first 100 years of photography, a camera was a box with a hole in it. In the age of digital photography, that is no longer true. ISO is no longer limited by the chemicals on the film and with computer chips embedded in modern digital camera allow for a variety of new features. One such feature is live remote shooting. This feature allows the camera operator to connect the Canon camera body to a computer and control the camera remotely with a computer.
On my second night of imaging, I connected my Canon camera to my Lenovo laptop and instantly, I have a 10 inch remote view finder which I could use to bring the moon into clear focus and experiment with different exposures. Additionally, it allowed me to share the experience with my wife and son at the same time, which I hope will continue to evolve as we look deeper into the solar system.
On my second night of lunar photography, I have partially address the focus issue discovered in my first attempt. I have much happier with my results, however, there is still sharpness available within this primitive imaging platform.
While I was taking photographs using my laptop, I noticed some shaking. At no point during this shaking was a touching either the tripods, camera or the telescope. The platform was setup on our concrete patio so we were as solid as can be. The answer is simply the wind, as a very slight breeze and I mean very slight breeze was catching on the telescope at it’s tripod. This caused a very slight vibration which was then magnified by the 1120 mm telescope into the camera.
The National Geographic telescope which I am using included a very light weight tripod. The tripod head was never very good at locking the telescope down to be free from movement and a camera connected to this configuration only exacerbates the problem. So the next step beyond more photography is to address the dual trip setup and develop an stable telescope tripod with a heavier duty tripod, tripod head and telescope imaging system. If nothing else solving this problem should make it easier to use the platform and perhaps image objects such as Jupiter, Saturn and Mars.