Pierre Méchain, the discoverer of Messier 101, described it as a:
"nebula without star, very obscure and pretty large, 6' to 7' in diameter, between the left hand of Bootes and the tail of the great Bear. It is difficult to distinguish when one lits the [grating] wires."
Imagine that the light, to travel acorss M101 it will take around 170'000 Years !!😲😲😲 and to reach us the Light needed around 20 milions years, at a speed of 300000m/s !
I leave here the link of Wikipedia about more information about the M101so you can take a read...
I took this picture of the M101 on 04 May '21, in a pretty cold evening up in the mountain region of central part of Switzerland in the Wägitaler valley.
Its pretty dark up there probably a Bortle 4 Sky a really beautiful lake (DAM actually) is also there.
So I prepared my setup , before driving there I collimate my RC 6" Scope as vest I could, its not difficult but it is not so easy, you need to take really small adjustment steps between the Secondary mirror, the Primary mirror and the Focuser tilt plate.
To to that I use a Howie Glatter Laser collimation tool, ad Cheshire and a set of allen key and a lot of patience...
Anyway, Its Monday evening around 10PM, Im around 890 msl so is pretty cold even now in May, after the initial setup, polar Alignement and Focusing and Pointing to the object (M101) I' m ready, to take a bounch of picture of this nice DSO. Oh yea Tuesday I work...ronf...ronf 🤦♂️🤦♂️🤷♂️🤷♂️😴😴.
S I took around 40 Light Frame RGB with my ZWO 533 camera and the TS 6" at full Focal lenght of 1370mm, I'm waiting a reducer but not yet arrived, to improve the Focal Ratio from F9 to F6.75 (x 0.75 reducer) of course the FL will be reduced as well to 1027 mm, not bad at all.
This is my second DSO with this scope I'm pretty happy with the result.
With such FL you need to be very precise in everything, Setup, Polar Alignment, Pointing, etc..et no room for error if not your pictures will be not good at all.
I use great software all open source, in particular NINA & PHD2 which are really great piece of Software, thanks to all the guys involved in the Dev. of such great utilities.
For the Post I use Pixinsight, which I'm still learning it, It is not easy especially in the beginning, but after some time you will find it very nice software.
In this particular picture I had only 2,7 Hrs of integration so it is not the best picture ever of course, but slowly I'm improving.