Paracorr and focus travel

[scarp15]

I would like to ask users of a paracorr, what adjustments, if any they have made to accommodate correct focus travel.

Many newtonian focusers require extension tubes to achieve inward and outward focus, depending on the range of eyepieces used. So for example if your focuser was fitted with say a 2" (50mm) extension tube, which was usable for a range of 2" low power to 1.25" high power e.p's, would the addition of a paracorr require a shorter extension tube?

[crashtestdummy]

Can only tell you my results with my scope and eyepieces

16" f4.5 dob,moonlite focuser and all 2" es 100° eyepieces.for the paracorr I had to actually remove some of the base plate spacers to achieve enough inward focus with the 20mm at setting 3 on the paracorr.my 30mm es 82 at setting one works ok and my es 14mm at setting 5 is ok but quite far out but not messed fully with the 14mm and 9mm yet.if needed I would just need nothing more than a short extension tube.

Hope that makes sense

[Moonshane]

a paracorr moves the focus point in by about 18mm. www.televue.com/pdf/literature/Pacacorr%20Type-2%20Instructions.pdf

the other advantage of a paracorr is that you can use the barrel as an extension tube. e.g. with my 12" scope I need a 2" extension without the paracorr but with it I ditch the extension and just pull the paracorr out by maybe 30mm.

[scarp15]

Thanks guys for the insight, info and links.