known as the Seven Sisters and Messier 45, are an open star cluster
containing middle-aged, hot B-type stars located in the constellation
of Taurus. It is among the
star clusters nearest Earth and is the cluster most obvious to the
naked eye in the night sky.
The cluster is dominated by hot blue and luminous stars that have
formed within the last 100 million years. Reflection nebulae around
the brightest stars were once thought to be left over material from
the formation of the cluster, but are now considered likely to be an
unrelated dust cloud in the interstellar medium through which the
stars are currently passing.
Computer simulations have shown that the Pleiades were probably formed from a compact configuration that resembled the Orion Nebula. Astronomers estimate that the cluster will survive for about another 250 million years, after which it will disperse due to gravitational interactions with its galactic neighborhood.
are my first Pleiades for a just modified NEQ6Pro, assembly with belt
drive instead of gears and new bearings. I modified the mount myself
and after this photo session I see what else I need to improve and
what activities I did not take to know and what mistakes I made.
first night I realized, that I had not aligned the polar scope axis
with the mount, which practically prevented me from setting the mount
to polar correctly. I had no idea that this should be done. Because
of that the first photo session is just only 90 [s] exposure. That’s
all I could get without the correct align of mount to polar. The next
day I did my “lessons” and in the evening when the polar
appeared in the sky, I aligned the mount axis as much as possible at
-10 ° [C] degree by turning three tiny screws with a tiny allen key,
in poor light, without winter gloves on my hands, until I was able to
keep the key in this freeze night.
aligned the mount as it was possible to carry out exposure of about
150 [s] at 1000/200 [mm] focal length of my telescope without guidng,
but every second / third frame was still with traveling stars. I
reduced the exposure time to 2 [min] to reduce the amount of waste
material, still I had every 4-6 frame broken. I determined that the
axle clearance pressure was set incorrectly in one of axis, which
caused a noticeable small play, which I still have to cancel by
adjusting the pressure.
I will refine the assembly and improve the results. When my Mgen Lacerta II comes back to me, then this assembly with this tube will show a what deserve. I hope.
Photos taken on 23-25.1.2020 at Żabnica with company of a friend Tomasz Siekiera, who made the square available for astrophotography. Thanks Tomek! 🙂
- Canon EOS 6D (no mod.),
- SkyWatcher Newton 1000/200 [mm] F5,
- Coma corrector,
- NEQ6Pro modification with some mistakes in the calibration process I’ve made due to my knowledge gaps. I’ll work on it in the near future.
Stacking, composition and data:
- Astro Pixel Processor
- GIMP v2.10.14 + plug-ins (Linux)
- Lights in the two session: 175 x 90[s] ISO 1600 + 32 x 120[s] ISO 1600 = 207 – 10% bad quality rejected frames = 186 best frames with different time exposure,
- Flats: 35 ISO-1600,
- Dark Flats: 42 ISO-1600,
- Darks: 42 ISO-1600,
- Bias: 20 ISO-1600