Re: Meade LX200 - How to use with a DSI? Backfocus
- From: RMOLLISE <rmollise@xxxxxxxxxxx>
- Date: 17 May 2007 06:29:03 -0700
On May 16, 11:04 am, canopus56 <canopu...@xxxxxxxxx> wrote:
For this summer, I have the opportunity to use a publically available
LX200 Classic version. I would like to expand to some imaging. I have
a Meade DSI but am unsure how back focus works on a Meade LX2000 in
terms of aligning an object to a chip using a flip mirror.
My usual scopes are a 10" GEM mounted newt and a 5 1/4" refractor. For
those scopes I have backfocus and target centering problems reasonably
worked out - I have a flip mirror, a parfocal eyepiece set up, and for
the newt, a low-profile focuser. This makes getting the image on the
small DSI chip a _relatively_ easy task. A separate off-axis 70mm
refractor is used for alignment and guiding.
Looking at the Meade LX200 - and one equipped with an autofocus
controller - it is unclear to me how there is enough back focus room
on these SCTs. How much backfocus room is there? Is there enough room
to accomodate a flip mirror, a parfocal ep and a camera. Most pictures
that I see of LX200s and most people I have seen using them seem to
just stick the camera directly into the visual back with no flip-
mirror or parfocal e.p.
That setup seems like it would make targeting the feature onto a small
DSI chip quite difficult - that is aligning the feature by using the
camera view.
In reading the LX200GPS manual, there appears to be separate primary
mirror lock and adjust knob. In the LX200 classic manual, there is no
primary mirror lock knob. The scope I will be using an LX200
classic.
Specifically, what is the backfocus distance on an LX200 classic?
- Clear Skies - Canopus56
Hi:
Why do you need a flip mirror? The go-to on the Classic is usually
good enough to easily put DSOs on the DSI chip (especially if you'll
be shooting at f/6.3 or f/3.3 as most DSI users do).
The only problem you'll have is if you use a flip mirror in
conjunction with a 3.3 or 6.3 reducer. If you do indeed intend to
image with the DSI at f/10, you should have enough backfocus with a
flip mirror in place.
I'd forget flip mirrors. You don't need 'em for deep sky imaging. They
do work well for hight mag planetary imaging, and I do use the Meade
flip mirror to help for that.
Unk Rod
.
- Follow-Ups:
- Re: Meade LX200 - How to use with a DSI? Backfocus
- From: canopus56
- Re: Meade LX200 - How to use with a DSI? Backfocus
- References:
- Meade LX200 - How to use with a DSI? Backfocus
- From: canopus56
- Meade LX200 - How to use with a DSI? Backfocus
- Prev by Date: Re: S&K Page
- Next by Date: Re: Universes, was Re: Venus- why not a good planet to view?
- Previous by thread: Meade LX200 - How to use with a DSI? Backfocus
- Next by thread: Re: Meade LX200 - How to use with a DSI? Backfocus
- Index(es):
Relevant Pages
|
