May 5, 2011

M101 (5-3-2011)

I've imaged this mammoth galaxy before, here.  But at only, roughly, 23 million light years away and stretching approximately 170,000 light years from side to side, this face-on spiral giant is always a welcome sight.  This is partly why I wanted to use the 10": the scope is big enough to hint at galactic details.  M101 is always a challenging target, though.  The dynamic range is massive.  The galaxy in fact has other spiral arms that I have not pictured here.  Because the image was taken from the suburbs, light pollution washes out the fainter parts.  Just for comparison, I have included below a version with the light pollution left in.  Also, this is just 14x10', not enough time to pick up these fainter portions even if I was at a darker site.  Even my earlier image of M101 is a bit deeper.  It was over 50% longer exposure time from the same site with the same camera at about the same focal ratio.

Telescope: Orion 10" f/4.7 Newtonian
Camera & Exposure: SXVF-H9C, 14x10'
Coma Corrector: Baader RCC I
Filter: IDAS-LPS2
Guiding: Orion Deluxe OAG, Meade DSI Pro, PHD
Mount: Takahashi NJP
Software: Nebulosity, Maxim DL, Photoshop CS3
Location: The Woodlands, TX

6 comments:

RoryG said...

I really like the detail of the dust lanes and the colors of the star forming regions in this one. I'm no expert, but I understand the difficulties inherent in imaging this object.

Polaris B said...

Thanks, Rory! Yes, this is a tough one. All the blacked out parts of my image actually contain galactic arms. The galaxy is larger than my camera's field of view on this scope. So all the while I'm cutting out skyglow I also know I'm cutting out signal from the galaxy. M101 forces tough choices on anyone not willing or able to image from the desert for 18 hours.

Phil said...

This picture knocked my socks off! Amazing!

Polaris B said...

Thanks, Phil! I was able to get some good subs.

JaNae said...

keep posted, these are so cool!!!

Polaris B said...

Thanks, JaNae!