Focus Reducer Question

[austen4]

Hello all,

Bare with me . If I got a 0.5x or 0.8x focal reducer, I understand that the focus point would move into the focuser more. Now I was wondering, how much would it move into the focuser? I have a Newtonian scope and I am about to do move the mirror up the tube and I could make it for using a focal reducer but spacers can easily be added if I didn't want to use it.

Thanks in advance

[austen4]

and if anyone has any suggestions for focal reducers please enlighten me

[steelfixer]

Austin I am intrieged to know why you want to do this.

[Merlin66]

It would depend on the design of the reducer. For instance the Meade x0.63 reducer is 240mm focal length and the distance from the reducer to the CCD is designed for 110mm, but the lens needs to be about 200mm INSIDE the original prime focus.

Hope this helps.

[austen4]

Austin I am intrieged to know why you want to do this.

I wanted to lower the magnification of the scope with my DSLR as I do not have a lens and am doing a panoramic photos on the sky.

It would depend on the design of the reducer. For instance the Meade x0.63 reducer is 240mm focal length and the distance from the reducer to the CCD is designed for 110mm, but the lens needs to be about 200mm INSIDE the original prime focus.

Hope this helps.

Thanks Merlin66,

is there any other reducers that have a smaller distance that need to be in the focuser?

Thanks again all for helping

[Merlin66]

There's the Skywatcher series and others, but they are generally designed for refractors not Newtonians.

All the SCT type, Optec etc work on the same principle as the Meade/ Celestron.

[austen4]

There's the Skywatcher series and others, but they are generally designed for refractors not Newtonians.

All the SCT type, Optec etc work on the same principle as the Meade/ Celestron.

ok thanks, looks like I will not be using a reducer