Wide Field Imaging Kit

Step 1: play around with the lens during the daytime. Firstly, this is a manual focus lens when connected to a Canon EOS. A few shots using the focus scale on the lens didn’t produce sharp images. I looked online to find numerous reports that this lens is often shipped with a badly calibrated focus ring; good to know. So I tried a star test using Live View to focus on a bright star. And here is the result: the lens is actually focused at infinity when the lens scale is set to a distance of 3 feet! Now I have an Astronomik CLS filter added, which will affect the focus a little, but still, however you look at it the focus ring was incorrectly set in the factory:

Samyang 14mm F2.8 focussed on infinity!
Samyang 14mm F2.8 focused on infinity!

Step 2: test the new lens ¬†without guiding. Here is the first result, a stack of 8 x 2min exposures with the lens pointing towards Polaris. A speed of ISO100 was used, with the lens wide open at F2.8. I stacked the images using the “Startrails” program. Dew ultimately coated the expanse of exposure lens.

First light over Winscombe, Somerset.

Step 3: try out the same process capturing more frames. This time I shot 41 frames of 2 minutes at ISO 2.8/F2.8. Streaks of cloud came and went during the exposures so I eventually chose to stack 35 frames, having wrapped a Kendrick Dew strap around the lens to keep the moisture away.

Startrails in August as a meteor skirts the pole.
The Earth turns for 2 hours on a clear August night, as a meteor skirts the Pole.

Step 4: try the new IOptron Skytracker:

iOptron Skytracker mounted on top of a Vixen Porta II tripod.
The skytracker mounted on top of a Vixen Porta II tripod. An adaptor to allow the Porta’s M10 bolt to mate with the 3/8″ thread on the iOptron was needed. There is probably a simpler solution than mine! Answers on a postcard…
iOptron Skytracker with a Canon EOS and Samyang 14mm lens
The polar scope and the ball head are shown here.
iOptron Skytracker showing the controls
Underside view showing the N-S switch, the 1x/0.5x switch and the on-off switch. 4 AA batteries live inside.