Not orion this time

[Devon_Demon]

Been trying zwo 1600 cool osc with my canon 24-105 usml lens but having mixed sucess with my focus so thought i would try making a focus mask, results below.

I made a lens hood from thick cardboard tube and flocked the inside, glued a 77mm screw on filter flange to the tube and attached my old graduated filter box adapter to the lens hood (slips on if it were made for it) push on pull off , trimmed the edges off an unused bahtinov mask for a 72mm scope so would fit filter box and centred.  As it was clear i thought i would give it a try, slewed to a bright star and lo and behold nice diffraction spikes.

The time was getting on and Didn't want to miss Morse. so did one 10min sub just aimed at milky way , no calibration just cropped out amp glow bit of stretching in pixinsight.

Regards

Graham

 

[ecuador]

Hmm, I don't see a focus problem, as much as stars red above, blue below, which is a bit like atmospheric diffraction? How high above the horizon was your target when you shot this?

[Devon_Demon]

Ecuador

This was a test shot with bahtinov mask for focus which i think works rather well.

this was shot right overhead, could be lens was wide open @ F4, trouble is i have to attach to my dslr to change F stop then re attach to 1600 asi .

Im hoping to get a samyang 135mm F2 manual lens soon so will be easier to stop down.

Regards

Graham

[Devon_Demon]

Just had a thought I don't think this camera has any sort of uv/ir filtering so that's probably why the stars seem to have an aberration, this lens used with my canon 6 d the images are very clean... 

regards

graham