Coma Corrector Skywatcher 150pds

[Gerry Casa Christiana]

Hello

Hopefully tomorrow I'm going to be ordering a eq6 with a SW150pds. I've noticed one review on the FLO website that says the coma corrector for this telescope causes a problem with the focuser as there is not much leeway. Has anyone else had this problem? If so should I buy another make for my skywatcher?

Here is the review which mentions the problem

Read this if you Have a 150Pds!
Wednesday, 3 June 2015  |  Stephen
Corrects the coma on my Explorer 150Pds almost perfectly across the field of view of my Canon 450D.
I was however disappointed to find that because it also acts as .9x reducer the focuser has to be wound in so there's only 7mm of inward travel left. The problem with this is that the inside edge of the focus tube protrudes in front of the primary mirror causing images of bright stars to have bite marks in them and all stars are slightly D shaped. This would be forgivable if it was made by anyone other than Skywatcher but because the 150Pds is one of the scopes this CC is specifically designed for I find it very poor.
The problem can be fixed by cutting the inside end of the focus tube to make it shorter but this does mean its possible to wind the focuser too far out so that it comes off its mounting wheels.

[StamosP]

I would recommend to stay away from the SW coma corrector.

It's a fact that it causes bite marks in stars but that's "easily" fixed with a little diy. You can cut the focuser's tube (i have shortened my 130pds' drawtube by 2cm) or you can move the primary mirror up by 1-2cm (that's a lot easier and reversible).

The corrector's biggest problem is that it produces reflections and chromatic aberration. So you end up with a newtonian scope which has CA! Totally unacceptable...

Here is my review: http://www.astroshop.eu/field-flatteners-other-photo-accessories/skywatcher-2-coma-corrector-for-newtonian-telescopes/p,18852#tab_bar_2_select

Notice that i don't mention the CA, back then i didn't have the knowledge, i was taking my first steps in imaging...

Now i would rate it 0/5.

[Thalestris24]

Hi

Yeah, I believe there can be a problem when using it with a dslr. It's possible to work around it either by cutting the end off the focus tube or by moving the main mirror up the tube a little. An alternative is the TS CC which doesn't have the problem but increases the focal length somewhat. This also applies to the 130pds. If you do a search on here I'm sure you will find references and fixes

Louise