M51, the Whirlpool Galaxy from Okie-Tex

M51, The Whirlpool Galaxy by Jaxon Taylor, on Flickr


About 2 hours and 15 minutes of LRGB data of through my Esprit 120 at native F/7 at OTSP with my ZWO ASI294mm Pro.

Here is an up-close crop to show off the detail:


Got several other Galaxy’s in this picture. I see 3 for sure and maybe 7 total not counting M51.

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I forgot I learned from the PI class how to annotate objects in the image. Check this out, it highlights most of what I would consider a potential galaxy in the image, whether it’s an NGC/ IC object, or one of these small PGC objects. I think there are even more galaxies in the image, but this gets most of them for sure.


Great image! I’m glad you liked the PI class. The annotated information adds situational awarness to the pictures.

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Yeah, I had burned myself out with astronomy the past year, but OTSP and what I learned at the PI class really helped get me motivated again. The PI class really helped me with finding easier ways of doings things I used to work really hard on, spending a lot of time on.
The annotated image really does help you visualize how much is out there.

Well done Jaxon :+1:

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Nice job Jaxon. Lots of detail.

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Fantastic job Jaxon. Really liked your work. Keep posting.


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Lovely image. About how much magnification did you use?

Magnification with imaging isn’t usually a good metric. What if you see the image on a cell phone, or what about on a large projector screen? Magnification is a much more useful term when using eyepieces. I don’t use an eyepiece as I put the camera directly into the focus tube. A more useful metric is field of view of the entire image. Using a calculator tool, my image is about 1.3 degrees by 0.9 degrees. This is about the angular size of the tip of your pinky at arms length.

Hopefully that makes sense!


Okay I get that. So the focal length of you scope then defines the magnification. Is that correct?

Magnification is usually a term for visual Astronomy and eyepieces. If I remember right, the focal length of Jaxon’s refractor is about 850mm? If he used his ASI294 camera, that sensor is a micro 4/3rd so that “punches in” a bit more when compared to an APS-C or Full-frame sensor.

Yes, this was with the 294 camera. The main telescope focal length and eyepiece focal length will define magnification. Simply divide the telescope’s FL by the eyepiece’s. For example, a 20mm FL eyepiece on a 1000mm FL scope yields a magnification of 50x. The larger the magnification, the larger an object looks. However, for a camera inserted into the telescope, the only things that matter really are the telescope’s focal length and the physical size of the camera’s imaging sensor. The larger the focal length, the larger objects appear on the same exact camera. However, if you choose a camera with very large sensor, you will be seeing more of the imaging circle, thus, you’ll see a larger part of the sky, and thus overall the object might appear smaller. It’s kind of a weird illusion.

The big difference between what we are doing and what you are doing is that you use a camera, which takes an image that comes out of the eyepiece of the telescope. There magnification makes sense to talk about. However, we do not use an eyepiece, that’s where all of this differs.