BRESSER 4964131 Polar Finderscope for PM-100 Instruction Manual
- June 3, 2024
- BRESSER
Table of Contents
BRESSER 4964131 Polar Finderscope for PM-100 Instruction Manual
Scope of delivery
Polar finder scope with illuminated reticle
Additionally needed tools (not included):
Hex key 8mm and Phillips screwdriver
Illumination
Before you can switch on the illuminator (1; Figure 1), you have to remove
the battery strip. Unscrew the cap with the knurling (2; Figure 1). Remove
the security strip and screw the cap back on. Locate the ON/OFF switch on
the upper end of the illuminator (3; Figure 1). It also enables you to
adjust the brightness.
Focusing the polar finder scope
Focusing can be done before the installation of the finder scope. Look through the scope at an object that is at least 100m away. If the image is not sharp, look through the scope while turning the eyepiece (5; Figure 1) until the image is sharp.
Mounting the polar finder scope
Remove the LED illuminator from the finder scope (1, Fig. 1).
Insert the O-ring from the front onto the finder scope (1, Fig. 3).
Put the retaining ring (2,Fig.3) on the pole viewfinder and fix it with
the 3 small cross-head screws. Tighten the screws evenly so that the pole
finder can still be turned in the holder with some resistance.
Now screw on the LED illuminator again.
Now fix the pole viewfinder to the photo mount (Fig.2) using the 8mm
fixing screw (6,Fig.1) included in the scope of delivery.
Using the polar finder scope
Orient yourself towards the sky. To align your mount to the celestial pole
with the help of your polar finder scope, you need unobstructed view towards
the northern part of the sky (or to the south, if you are using the telescope
in the southern hemisphere, such as Australia).
The following procedure applies to aligning the telescope for the use on the northern hemisphere, such as Europe or North America. Look for the constellation „Big Dipper“. The Big Dipper represents a part oft he constellation „Big Bear (Ursa Major)“. Depending on the season you can see the constellation at different locations at dusk: in the winter it can be seen just above the northern horizon, in spring halfway up in the north east, in the summer almost directly above in the north, and in the autumn in the north west. Figure 4 shows you the northern part oft he sky at dusk in the beginning of January.
The Big Dipper /Big Bear is located directly above the northern horizon. We
can spot the three stars that form the handle of the Big Dipper at the middle
left and two bright stars at the other end of the constellation (Fig. 6),
one of them being the star „Dubhe“ in the upper right. We need those „rear“
stars to get tot he North Star (Polaris). If you prolong the line that is
formed by those two yellow stars oft he Big Dipper you will get tot he
brightest star in the constellation Little Dipper/Little Bear (Ursa Minor).
This is the North Star (Polaris).
The North Star may be located in the immediate vicinity oft he north celestial
pole, but it is not located directly at the pole. For this reason it does
circle the pole during the day/year like any other star that circle the
celestial pole.
We now have to find out on which position on this circle the star is located
at this very moment. For this, let us refer to **figure 5.
**
Figure 5 shows the engraving on the reticle of the polar finder scope.
You may notice three figures with little circles that are connected with
lines.
These symbols represent constellations.. To align the mount onto the north
celestial pole we need the constellation in the upper left and the
constellation below the middle at the right.
You may have recognized the left constellation already – it ist he Big Dipper,
that we already located successfully.
The other constellation is Cassiopeia which we have to locate now. To do this,
let us have a look onto figure 6, which is simply showing a bigger part of the
sky then figure 4 above:
We recognize the Big Dipper at the lower part in the middle of the field of view, the North Star almost in the middle oft he picture and a constellation at the upper end of the picture just slightly to the right of the middle. This constellation looks like a W turned upside down – Cassiopeia. We have marked stars in each of the constellations for you: the first star in the Big Dippers handle (Alkaid), Polaris and the star at the lower right in the constellation Cassiopeia (Epsilon Cassiopeia). These three stars are forming a line.
Now we are moving the polar finder scope in it´s bracket until the line in the
reticle aligns with the orientation of the corresponding line at the sky
(Fig. 7).
Please notice the difference tot he image oft he reticle in the beginning of this manual (figure 5): the position oft he constellation symbols in the reticle now aligns with the orientation oft he real constellations at the sky. Now you move the mount only with the fine adjustment knobs for azimuth and altitude until Polaris is positioned at the right place in the line in the reticle – we have marked this position already for you with a white dot star. Your mount is now aligned to the North Celestial Pole.
Aligning the mount to the Southern Celestial Pole is analogous to the
alignment described above. The constellations that help us orient the reticle
are the Southern Cross (or, more precisely its brightest star, Acrux) and the
brightest
star in the constellation Eridanus (Achene). The star that has to be
positioned into the right place in the reticle is Polaris Australis (Sigma
Octans).
Customer Support
Bresser GmbH
D-46414 Rhede Gutenbergstr.
Germany
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www.bresser.de
