Ok, this may have been done before but i haven't come across it, but for what it’s worth and considering the good will of member’s festive seasonal tolerances, I thought I’d share my experiment with you. If you have already successfully increased magnification for photography by more simple means read no further, or let me know.
I have just purchased a Skywatcher ed120 APO and from initial tests am very impressed. But having just sold a Celestron C8 to appropriate the funds I am some what missing the additional luxury and warm fuzzy feeling of the additional focal length, especially for lunar imaging.
So how do you beef up the magnification for DSLR photography on a scope with 900ml focal length if you do not have special adapters or lenses? (Incidentally, if you do know what adapters or eye pieces are required I would be grateful for your replies)
Try the following if you have the same equipment as I have:
- Insert your 2” diagonal into the rear of your focuser
- Unscrew the bottom lens thingy at the end of your 2” 2x Barlow so all you have is the Barlow lens itself
- Screw the Barlow lens on to the front filter thread of your 2” field flattener; I have an Astrotech and Hotech flattener so the choice is optional
- Attach the Barlow lens and Flattener to your DSLR camera via the appropriate T ring
- Insert the whole lot into your 2” diagonal
- Turn the focus knobs until you have focus
It actually works. My shots of the moon were equal to the Barlow magnification and the image was sharp. I did a further test simply inserting the entire Barlow piece in to the diagonal and simply could not get focus. Also I tried the whole experiment again without the diagonal and could not get focus. I set the capture speed on Nebulosity to between .0100 and .0400 and started to take sharp images of the moon with success.
Now I know many of you out there probably have projection eyepieces of some kind or means of increasing magnification, but at this stage I do not; I simply borrowed a mates Barlow and got bored watching TV over the Christmas break and decided to have a play with things in the shed.
Anyway I thought I’d just share my thoughts. If someone out there can steer me in the right direction to increase magnification for photography with a short focal length scope just let me know.
Best Regards
Carl Rainer