Focal Reducer

[robindurant]

I am toying with buying a 6.3 Focal Reducer for my 8i. SCT I learn that it is an advantage for astro photography by shortening the exposure time and widening the field. It this correct and does it mean that when used it reduces the magnification.

[Albireo380]

Yes - it should increase the FOV, shorten the exposure time and reduce the magnification. But one word of caution. I and a friend both have Meade 6.3 focal reducers and LX90's. Neither of us can achieve focus on our LX90's using the FR - not enough forward focus. Haven't figured out how to get round this problem yet. problem goes away when a Barlow is also used - but then not much point on having both in the light path, is there.

Any ideas how the problem is solved???

Tom

[Kaptain Klevtsov]

Are you using a diagonal between the FR and the EP? The amount of reduction that you get from a FR depends on the distance between the EP or camera and the FR. This has a significant effect on where the focus point is as well.

With my Skywatcher Newt. and modified webcam, I had to cut down the nosepiece to move the FR closer to the chip in order to reach focus.

Captain Chaos

[FLO]

A focal reducer is primarily a photographic accessory so, as CC says, it is designed with the assumption that you are not using a diagonal.

[robindurant]

Hi CC & Steve

I will be mostly using it on Prime Focus Astro photography although I did wonder if it would be an advantage FOV wise though my diagonal and EP, obviously not from what you say.

Robin

[FLO]

I am told that Meade's own screw-in 2" diagonal will allow focus(?)