Afocal photography using your Telescope.
Camera’s I am currently using are: Canon 350D DSLR, Nikon s220 CoolPix and the Iphone 3gs.
My Current scope the SkyWatcher 200p is excellent build quality and is capable of handling a DSLR at prime focus. My previous OTA the SkyWatcher 130pm was not capable of handling such weight at the focus tube.
This is why I started in Afocal Photography.
Where to start:
I suppose apart from the OTA, the other considerations should be the camera and eyepiece, from my experience the camera needs to be light and easy to handle at night.
Nikon s220 Camera
I specifically chose the Nikon s220 because of its small size, 10MegaPixel quality, Video, Zoom lens and of course it’s very light.
Iphone 3gs
Small, light and it’s an Iphone, what more can you say.
One of the considerations with an Iphone is the position of the camera lens sometimes difficult to angle it right. Now you could just hold it up to the eyepiece and hope for the best? I found this very frustrating and unusable and another method had to be found.
Canon 350D
Medium weight Camera, my first real DSLR.
Eyepieces.
The main thing with eyepieces and Afocal photography is the eye relief if it’s to small it’s difficult to get the camera to focus through the eyepiece this is why I prefer wider eye relief eyepieces for Afocal photography. When using my Iphone I always prefer my SkyWatcher 7-21mm Zoom eyepiece usually set to about 11-21mm this allows the Iphone to be able to view objects through the eyepiece.
When using the Nikon s220 camera a standard telescope mount is used (these are available from most dealers).
This is my camera mount:
And these 2 eyepieces are my favourites when using the Nikon s220 camera.
A 32mm camera projection eyepiece and a 25mm wide-angle long eye relief eyepiece.
The Iphone 3gs
The phone proved difficult to use at the scope until I came across Mike Weasners site on Afocal Iphone Photography: You should check out Mikes site, it’s full of very useful information and you may get some ideas for your own version, this one is mine.
My Iphone adaptor is made from an old camera adaptor and an Iphone holder.
The most important part is getting the holder in the correct position to allow the Iphone camera to look through the eyepiece at the correct angle.
I have looked at exit pupil and measurements for Iphone camera but I think this is beyond the scope of the small starter article, and to be honest trial and error is a great way to learn the basics.
Whatever you use bear in mind that it has to be used at night and usually illuminated by a red torch, so it has to be easy to set up and easy to use.
Another consideration is focussing the telescope correctly, there is no point in taking an out of focus photograph, do your best while at the scope to get correct focus, I have lost track of the number of pictures I’ve deleted once I’m back home, through poor focus. I always ask myself now, (a) What’s in the picture (b) is it focussed correctly (c) will I keep this picture once I’m home?
