Following the good advice from this blog, I ordered the Mylar emergency blankets which arrived today. I had prepared some cardboard fixtures but as it turned out they did not seem too steady. I finally decided to go ahead affix the two sheets of Mylar with some office tape and a rubber band to a 500mm mirror lens. Prior to this I focused on the moon last night and locked the lens at infinity (hope this works).
Besides this 500mm lens, I also prepared a filter for a 250mm lens, but I am not sure that that is the correct lens for this project. The sun would not look as big, imagine Venus! The only reason why I am considering this is because the lens glass (for the 250mm) is of better quality. I don’t know which of the lenses to use, though I am leaning towards the 500mm lens regardless of quality.
I am also concerned about the correctness of the focusing procedure I used, I may acquire a very blurry image if I acquire anything viewable at all. Here is the second filter for the 250mm lens
Finally, the 7″ monitor I will most likely use to “monitor” the acquisition of images and the fine tuning of the focus.
The camera will be activated using one of these:
- wireless remote control
- iPhone App to control camera
As part of the preparations I ran a test today, Jun 4th. My 500mm lens is a “soft lens” of the type called “mirror lens”. I did not spend much on it, just wanted to photograph occasional birds and egrets, so I do not have great expectations.
At best this outcome can serve to depict what not to use in terms of lenses. Following is today’s test, that came out, as expected, too soft. Imagine Venus. I used as adviced, two sheets of Mylar as described in the paragraphs above. I wanted to perform the test at the same time of the Venus transit tomorrow but I forgot, so it was done 30 minutes past 6PM, the time at which the event will happen at my location.
If possible, I would like to hear what changes can be done to setting to improve this , I am thinking, maybe move to ISO 10o? The f stop of lens is fixed at 6.3.