Tarantula prime focus ED110

[skysurfer]

Yesterday night I made a picture of this nebula using the ED 110 with a Canon EOS 6.
Used a Flattener, ISO 1600 and 25 frames of 2 minutes.
The weird thing is is that the left edge of the image is blurred, but not the right edge and the rest, which are sharp.

[RickS (Rick)]

Sensor tilt, perhaps?

[Octane (Humayun)]

I used to have the same issues when imaging with my first refractor. The focuser had slop in it, which tended to do that.

The other thing is that you're using a 6D. You might need to get the spacing correct between the flattener, the scope and the camera.

H

[skysurfer]

Originally Posted by RickS

Sensor tilt, perhaps?

No, definitely not in the camera itself. The issue is only with the ED110. Probably there is some play in the three screws to hold the focuser on the tube which may tilt the sensor relatively to the optical axis.

[skysurfer]

The picture I made on 4 March was too blue.

I restacked all frames with Photoshop CS6 and postprocessed it.

Now the red Halpha nebulas are shown.

https://www.skysurfer.eu/skypics1/Ta...n-20170304.jpg

[Atmos (Colin)]