What lenses would be good for beginning shooting of DSO’s?

[tyresebro1]

Hey y’all! I’ve been considering an AP rig for some time and I’ve finally decided to do it. Right now the only gear I have is a Canon 60D ( is it good enough camera btw? ) and a small tripod. Which I’ll probably have to upgrade for the star tracker I’m planning on getting. But I have zero idea what lenses I should get. I don’t really like wide field shots, but if that’s where I can get started I’d be more than happy to. My budget is around $200-$300 after getting the star tracker. Thank you!

Ps if you need any more information that I didn’t include please ask, thanks again!

[CraigG]

Hello!

Although I can't speak to the pros and cons of specific lenses or the suitability of your Canon camera, I would encourage you to not rule out wide angle imaging in your new setup. Time exposures with a tracker and a wide angle lens should give you some wonderful images to inspire you for quite a while! Take a look at  Astrobin or Telescopius and search for images using your camera and wide angle shots, say 50-70mm. I think you'll be impressed with what you find.
You can also decide if you want to make the jump to a dedicated astro camera.

Good luck and check back in as needed!
-Craig

[susan-parker]

Hi,

I have been shooting with camera lenses for a couple of years and there are three issues to consider (well three that have impacted my images the most):

1: Geometry - if one does static-mount with many short exposures then geometry will impact the edges of the stacked images, if not good then one can also forget mosaics.

2: Chromatic Abberation - this is the "gotcha" in imaging. Basically when pushing the gain of the images post stacking the amount of out-of focus from the red-end may become noticable. Wide angle, not so much. At 105mm it becomes very noticable, and at 300mm it is huge.

3: Lens construction - modern lenses tend to have many elements, which work to mitagate the above. However for stars which are pin-point light sources the multiple lens groups are not necessarily perfectly aligned so on then has to stop down the lens to get an accpetable image.

E.g on my Irix 150mm macro, I have to stop down to f/4 before things start to work, even then it is not brilliant. But of course for DSO astrophotography one wants as much light as possible, so this is a sadness. My 105mm f/2.5 Nikkor from 1970's is far better in this regard, BUT geometry isn't as good and it has colour rings from the red end not being in focus.

I have a Tamron 500mm f/8 mirror lens, which doesn't have these problems, but anything much over 100mm does require tracking and for where I live in a city Bortal 8+ zone I am not getting the depth that the longer focal length would normally provide.

The best ballance is something like a Williams Optics Redcat or Spacecat, which is a really nice lens and solves all three of the above issues. With my Atik Horizon I get about 3 degrees of sky. It's above you stated budget, but do have a look at one if you can.

The attached pic shows the chromatic problem taken with my Horizon monochrome camera. This is with a dual narrow passband filter for the nebula emission zones and suplimental red R60 and blue B12 filters. The blue rings are in fact the RED spectrum coming through the red end filter, and would normally show up as red rings on a RGB DSLR camera.