Field flattener question

[ninjageezer]

I have fitted to my WO Z73 the WO adjustable field flattener.i adjusted it to the 11.7 mm as per instructions but not happy with outer parts of image (stars not perfect) i am using an astro modded canon 60d .i do know that the mod had a sensor adjustment not sure what that entailed and just wondered if this needed to be taken into account ,i have tried the adjuster down to 10mm on the scale and up to 13mm the other way but i've seen no real improvement ,any suggestions' please in case im missing something as a newbie.

[Anthonyexmouth]

Post an image, it's worth noting that fractions of a mm can make a difference, very easy to overshoot. 

[Iem1]

Not sure if this is of any relevance, but I have the same scope with a 600D.

I aim for around ~ 11.4 mm on the field flattener and to my eye at least it does the job. My 600D has an astro mod, but no sensor adjustment that I am aware of.

This is what it looks like.

 

[ninjageezer]

1 hour ago, Iem1 said:

Not sure if this is of any relevance, but I have the same scope with a 600D.

I aim for around ~ 11.4 mm on the field flattener and to my eye at least it does the job. My 600D has an astro mod, but no sensor adjustment that I am aware of.

This is what it looks like.

 

yup that's how mine is adjusted ,i will try playing with the distance, its not bad just the outer edges are not perfect.