First pics with 12" lx90 & Nikon D5300 ... flared stars.

[Paul-F]

Hi,

I have a 2007 vintage 12" LX90 LNT and have only used it for visual till now and have been pretty happy with appropriate collimation/sharpness.

Recently, I have got myself a DSLR so have taken some images of Lovejoy and M42 ... I was not impressed with sharpness/focus on the sensor so researched and made myself a Bahtinov Mask which gave me confidence I had got proper focus. Last night's seeing was not the best and I took the attached star image, (2 secs @ iso 6400) when the mask indicated good focus.

The stars are asymmetric with the flare more pronounced on the top (in this case) and there is this flare in all of my images (1s to 10s exp) which leads me to think its at the opitcs level. The comet is a 6s exposure:

Scope is mounted on the stock alt/az setup. My first aim is to get better star images (will improve visual use too) so wondering what I should look at to fix this (eg, collimation, optical path alignment, technique, camera). Suggestions please ..! I want to get the best I can with what I have now before spending more money

Bahtinov m

[Paul-F]

Here's an image of M42 showing that flaring evident on the top of the stars .... 2 sec exposure @ iso 6400:

[ronin]

The camera may not be sat correctly, the focuser was made before hanging about 1Kg of DSLR on it was common or maybe even considered. My first guess is that the focuser cannot hold the DSLR and that the DSLR is not sat orthogonal to the optical axis.

[Paul-F]

The camera may not be sat correctly, the focuser was made before hanging about 1Kg of DSLR on it was common or maybe even considered. My first guess is that the focuser cannot hold the DSLR and that the DSLR is not sat orthogonal to the optical axis.

I did have the camera in the diagonal - gonna try without the diagonal next ....