Dive into Astrophography Tonight!

The first images I took of the sky were from a point and shoot camera sitting on a stationary tripod. There’s fun to be had with equipment you might already have, but never thought to point at the night sky. That first point and shoot camera was a 2.1MP Fuji Finepix on a rickety tripod (that I still use on occasion). Unfortunately, I’m unable to find those wide-field shots from 12 years ago, but below is a single over-processed 30 second frame from my DSLR on that rickety old tripod taken last September in humid 95 degree heat. This was from when I first started to get back into this, but I’ll be getting back to the data to improve on the processing. The inset is of M31, the Andromeda Galaxy.

It has been very cold lately, seeing has been below average and I’ve been short on time. Setting up the camera instead of the telescope is more forgiving, only takes a few minutes and I can really set it and forget it. I only have kit lenses, so I’ve been experimenting with them. I don’t have all of the camera settings down to get the best images , so I might as well do my experimenting when conditions are less than ideal. The two images below are just playing around at this point. I wanted to see what is possible with pretty much just pointing the camera up and shooting away. There are some tricks to making these images better and getting the most out of a kit lens when shooting the sky. I’ll be applying those whenever it stops snowing here in Chicago and I’ll write about them then.

The first image is of Orion using the 18-55mm lens that came with my $150 camera. Its just 7×20 second exposures. I beleive it was at about 50mm, so there is some trailing. I just used the tripod and taped the CLS filter to the lens, as I didn’t have any step-down rings (yet). This was taken with a full moon about 20 degrees to the east.

I recently acquired a refurbished 75-300mm kit lens for $40 (and step-down rings). I purchased it mostly for daytime photography, but of course I’m going to point it at a dark sky. The image below is about 28 minutes of the area from M42 to the Horsehead and Flame nebulae at 200mm. Because it’s at 200mm I did use the EQ mount to track the sky. There are clearly some large issues to see if I can work out shooting with this lens. It’ll never be perfect, but I know it can be a lot better than the image below. There really are good reasons some of those lenses you see are at over over $1000 – note the large amount of lens distortion in the image. Regardless, I was happy to see that I could get something and start to learn about shooting the sky with lenses.

There are just a few criteria for the camera to start shooting the sky. Most cameras that aren’t phones have these capabilities.

1. Tripod mountable
   • You’ll have a 1/4″ threaded hole on the bottom of the camera.
2. Manual Focus
   • Cameras can’t focus on a star field, so you’ll need a way to manually focus to infinity. This can be very tricky to get perfect on a longer focal length. I use a PC with live-view since I already have it connected for BackyardEOS. On particularly bright nights I have to use test shots to see anything.
3. Remote or Delayed Shutter
   • Remote is better because you don’t have to touch the camera. A two second delay with a gentle touch is just OK on a sturdy tripod, but not ideal. A ten second delay is best. I use the PC and BackyardEOS for this. It’s no-touch and I can walk away.
4. Manual exposure setting.
   • You won’t need anything more than 30 seconds if you’re not tracking, and that’s the maximum on most point and shoot cameras with a wider lens (zoomed all the way out with a point and shoot).
   • You might need a remote shutter (or PC) and a bulb mode setting to go beyond 30 seconds. Check you camera for the max pre-configured exposure setting.

So that’s it. If you have a camera with these functions and a tripod, you can start shooting. If you already have a DSLR, you know you have these functions and can even get results with your kit lens. Follow these tips to see what your camera is capable of.

• Resist the temptation to zoom in. Keep the field wide. A wider field is more forgiving. The more you zoom, the shorter exposures need to be to avoid star trails unless you’re tracking. depending on where I’m shooting in the sky, I can go about 30 seconds per exposure with my kit lens at 18mm before trailing starts.
• Pick a rewarding target. In the Winter, look in the Southern sky to find Orion. Try to get the whole constellation in the frame. In the Summer, the Southern sky rewards you again, this time with the core of the Milky Way and all the DSOs embedded within. The Northern sky Milky way is also entertaining with the Andromeda Galaxy on the Eastern edge, but as a while it is not nearly as bright.
• Have realistic expectations. Most of the objects out there are tiny! These aren’t what you’re going to get with a basic camera setup. Galaxies outside of Andromeda will not show up with anything less than a 200mm lens, but that doesn’t mean that there aren’t plenty of large objects out there to shoot.
• Use a SkyMap app for your phone or tablet, or a planetarium software for your PC/Mac to help you point the camera at your intended target
• Focus on the brightest star you can find until you get it to a pinpoint. Take a test image to confirm the focus.
• If your camera has an adjustable ISO, play around with the settings. If you’re at a dark site, lock it in at 1600. If you have a ton of light pollution like I do, your image might blowout the bright sections at 30 seconds ISO1600 without a light pollution filter.

Most importantly, point the camera up and start experimenting. You need to figure out what works best for your camera on your skies. Many people may try to tell you what settings will work for you, but they aren’t using your camera on your skies. Use a little guidance and adjust accordingly rather than counting on exact information from a blog like this one to fit your needs. Ultimately, your own experimentation rather than trying to duplicate other’s methods will lead to your best results.

Have fun with it. Inspecting your images afterward is the best part. If you move on to stacking your images, you’ll pull even more out of them.  If you move on further and get a tracking mount, or a full blown equatorial telescope mount, you can use it with your camera and a bigger lens for even more impressive images.

Clear Skies – KA