Re: very newbie question re: declination

On Feb 29, 11:33 am, AstroSketc...@xxxxxxxxx wrote:
On Feb 29, 8:22 am, Tunderbar <tdcom...@xxxxxxxxx> wrote (with a bit
of snipping here and there):

According to your description, the mount and scope are set up is
correctly. But the declination circle still says 0.
. . . the manual:http://www.zhumell.com/manuals/Eclipse_user_guide.pdf

I looked at the manual.  There are several flaws contained therein.  I
started to provide corrections here, but someone other than me
received payment to write that manual;-)

Does this make sense? I do have it set up so the OTA is pointing at
Polaris, as is the mount, and the scale says 0 as per the
instructions. Is this a manufacturers "feature" that will cause me to
have to mentally calculate the correct declination from the
incorrectly set declination scale 0 degree point every time?

It's nonsense!! It appears that an error was made in manufacture, and
an unsuccessful attempt to correct it was made via the manual.

The good news is:  Almost no one (*seriously!*) uses the RA and Dec
circles on mounts similar to yours -- not even when the readings are
correct!  Most of the time there are better, more accurate methods to
point a telescope at celestial targets (such as utilizing the visible
stars, the eye, the finder, and star charts).

Some options you might consider: a) keep the scope, but ignore the
Dec. circle entirely, b) if possible (not real likely to succeed
though) try re-positioning the Dec. circle, c) improvise a second
arrow that points to the correct value on the Dec. circle. d) return
the telescope (though I would suggest checking out its optical
performance first.  If it performs sufficiently well it may still be
worth keeping), e) . . . f) . . ., etc.

You might also try contacting the manufacturer (or distributer) via
the contact information provided in the pdf document you linked to
earlier.  It would be interesting to hear what they would have to say!

Bill Greer
To sketch is to see.

Thanks. I was thinking that maybe I was seeing something that wasn't
there. Being new to the field, I'm very early on a steep learning
curve.

I've contacted the manufacturer by email asking why their mount puts
Polaris at 0 degrees and not 90. I'll report on the reply.

Having said that, it is my intent to learn and become well acquainted
with all the techniques used in astronomy, including making full use
of the equatorial mount and the RA/declination approach to finding
objects. It is no help at all that I will have to re-scale the
declination circle either physically be moving it or moving the
pointer arrow or mentally by having to do added calculations in my
head to get the true declination for any given point in the sky.

It is very sad that Zhumell would pull that kind of thing with an
entry level telescope. It is bound to frustrate the hell out people
new to the field and may discourage them from pursuing their interest.
.

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