Going to take the plunge...

[Carl M]

and get an 8" quattro for my birthday next month to replace my 200P dob OTA as its focal length is too long and is quite slow at f/6. Many benefits of the quattro over the current OTA with shorter focal length and faster focal ratio but with the challenge of keeping good collimation I want to keep my DSLR unmodded which is another reason why I'm opting for f/4 instead of a PDS, until of course I leave 6th form, get a job and hopefully get a proper CCD.

So, I know I will be needing a coma corrector but which is best out of the Baader and Skywatcher correctors? Are there any benefits or drawbacks between the two?

Thanks in advance,

Carl

[Tim]

Hi Carl.

Good luck with the Quattro. They perform very well, but as with any F4 reflector they do need to be set up correctly.

I have had good results using a Baader MPCC. It wont quite give you perfectly round stars right to the edge of the corners, but if you squared the image in line with the original height of the image, then you'd be pushed to notice the increase in size of the stars away from the coma free zone.

Apparently the Skywatcher corrector acts a slight reducer. I haven't used one of those though.

Cheers

Tim

[SamAndrew]

Good choice

I'm very happy with the Baader MPCC, but I don't think there's much in it between the two.

[Carl M]

Thanks for the comments. Think I will get the Baader MPCC then once FLO gets some more in stock. It also has a T-thread on it I believe so I can connect DSLR straight to it with a T-ring? Reguarding the SW one I dont think I'll want the quattro any faster than it already is until I'm comfortable with its mechanics. I've seen Dion's tutorial on youtube about advanced collimation which I assume will need to be performed on the quattro frequently to keep it in good collimation.

Thanks,

Carl

[SamAndrew]

Yes there is a T-thread on it to make things nice and easy

As for collimation, I don't check every time as I find it doesn't usually need adjusting; I'm reasonably careful not to bash the scope against anything when I put it back in the box, so it stays collimated eneough to keep me happy.

[ollypenrice]

You're dead right that DSLRs thrive on fast optics. The 'CCD-like' DSLR images (and you do see them) are always taken in fast optics. Get the collimation right and you'll be flying.

Olly