Before you rush into your backyard and expect to see a big, bright new star in the sky, my suggestion is to instead head over to spaceweathergallery.com/index.html
While you browse these images, look at the EXIF/exposure information the astronomers provide. When they compare their telescopes, they first mention the DIAMETER, not the focal length.


Say a 304mm, is 30cm in diameter, compared to 7...8cm diameter of your SLR's lens. f-ratios are not always mentioned and typically are between f/5...f/10, thus this 304mm telescope will have a focal length somewhere between 1500....3000mm
www.spaceweathergallery.com/indiv_upload.php?upload_id=93207&PHPSESSID=q95qo80ir5nekgo82k74mp58a5
www.spaceweathergallery.com/indiv_upload.php?upload_id=93205&PHPSESSID=q95qo80ir5nekgo82k74mp58a5
The discovery of SN2014J was made with a Celestron C14 : 14" f/11= 3910 mm focal length
You can enter your camera's sensor size and details about your SLR lenses & telescope-wishlist into Stellarium and have it plot the FOV for your combination.


To start astronomy and especially astrophotography, a good GOTO mount is more useful than a huge telescope (I have suggested that before) and here is a good example why : finding the dim M82 galaxy will be a lot easier with the help of precise controls and the GOTO-capabilities of a well-aligned mount than poking around the black sky with your camera on a tripod head. That tripod approach still works, it just more tedious. Some trick that can help you accomplish that faster :

• level the base below the tripod head ==> you want the camera stay leveled with respect to the horizon as you turn left & right
• if you have, better use a head with two separate axis instead of a ballhead. Geared adjustments are even better to make these tiny changes.
• invest $5 for an angle meter -- compare the measurements with the altitude information in Stellarium
• your target is dim & small but with high ISO & long exposures you can improve your view of the sky -- careful not to create too long trails.
• even if the supernova brightens to 9 or 8, it still is too dim to see with the naked, unaided eye. Even under a dark sky, Mag. 6 is the limit for unaided view. With urban light pollution stars need to be even brighter.

Of course you don't want to catch dim objects from a place with tons of light pollution -- a trip across the GGB or up the hills in the Peninsula will help a lot. Or try imaging with a special filter to eliminate the orange spectrum from the street lights.
Fortunately, M82 is high up in the sky (currently 40° by 9pm, 58° by 1:30am) thereby reducing the air mass and the impact of light pollution on a clear night.


Imaging this galaxy & supernova using a static tripod will be a tricky proposition and all examples I have seen were shot with cameras sitting on top of motorized (EQ) mounts. M82 is not too far from Polaris (20°) and that helps to reduce startrails but even with a "wide-angle" a 300mm focal length lens and high ISO, I think you still will end up with startrails. The examples you see here were shot with a large 9.25" f/10 telescope on a motorized mount.

So far my best result -- after 2 days of preparations & experimenting (weather and daytime work weren't lining up to get a better shot) :


Good luck with your own efforts

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