A great astrophotography lens is only as good as the images it produces. Not all camera lenses are created equal, and imaging a night sky full of stars has a way of pushing your photography gear to its limits.
On a recent astrophotography session in the backyard, I discovered how enjoyable it can be to squeeze in a brief mid-week session using a camera lens in place of the telescope.
For this imaging run, I used the refreshingly simple and affordable Canon EF 50mm F/1.8 lens. The lens was attached to my Canon Rebel T3i DSLR, which rode atop an iOptron SkyTracker camera mount.
(Those of you that have been following my blog for some time know how much I love my DSLR astrophotography.)
The difference this time around is that I’m able to get up and running in about 10 minutes. The lack of computer control and autoguiding saves a lot of time and effort – meaning I’m collecting data sooner.
Don’t believe me? Have a look at a recent shoot that took place on a less than perfect night.
A Budget Astrophotography Lens (Nifty Fifty)
The lens used in this video is often referred to as the “nifty fifty”. “Every photographer should own a 50mm f/1.8 lens as your first upgrade from the kit lens that came with your camera.” – Improvephotography.com
In the video above, I set out to capture the Orion Constellation using a Lens in place of a telescope. This is my “quick and dirty” imaging setup.
In this post, I’ll show you my results using a Canon lens that costs less than $150 USD brand new. I’ll also share some information on another affordable lens for astrophotography from Rokinon.
Using a Camera Lens instead of a Telescope
On nights when imaging time is limited, a great option is to set up a highly mobile setup that you can get up and running quickly.
Sure it would be great to capture light frames on a deep sky project using my primary imaging telescope (especially when you’ve got a William Optics FLT 132 on loan!) but that’s not always a practical choice in the middle of February.
A small sky-tracker camera mount can be set up and polar aligned within minutes
The process of setting up my complete deep sky telescope rig for a night of astrophotography takes time.
Even with a sound blueprint for setting up my non-permanent setup, the process can take upwards of an hour. This isn’t a problem on a warm Saturday in June, but a Monday night in February is an entirely different experience.
Another factor that went into consideration was my weather conditions. The clear sky chart was less than ideal, with the transparency meter looking a little pale.
Rather than setting myself up for a potentially wasted night due to weather, I took a chance on some wide field shots using my “spur of the moment” rig.
A Lightweight, Portable Solution
My Canon EOS Rebel T3i sitting atop the SkyTracker Pro Camera Mount
The iOptron SkyTracker Pro is a portable astrophotography mount that is perfect for taking wide-angle nightscape with a DSLR camera and lens. If you’re just getting into the hobby and interested in long exposure shots of the Milky Way – a star tracker mount like this what you want.
If you’re want to go a step further and use a small telescope – I’ve had success using the beefier SkyGuider Pro. Wide-field nightscapes are a lot of fun – and can be just as rewarding as a deep sky image.
My target was the Orion Constellation, including Barnard’s Loop. Using the Canon 50m lens with my T3i results in a focal length of 80mm (50mm x 1.6 crop factor), which happens to be a perfect fit when it comes to capturing the stars that make up Orion the hunter.
The Canon EF 50mm F/1.8 Lens
What’s the Best Lens for Astrophotography on a budget?
You may remember my announcement on Facebook about investing in a new Rokinon 14mm F/2.8 lens. This “budget” category lens was purchased with the idea of wide-angle nightscapes in mind.
There are many great lenses for astrophotography available, but these are two that I personally own and enjoy. The models mentioned below are both prime lenses with a fixed focal length. Although they are both affordable choices for astrophotography, their uses will vary.
Jerry Lodriguss has put together a helpful list of both Canon, Nikon, Sigma and Rokinon Lenses for Astrophotography on his website.
Left: Rokinon 14mm F/2.8 | Right: Canon 50mm F/1.8
The lenses listed below are both built for a Canon DSLR body because that’s what I currently shoot with. Nikon has comparable lenses (Nikkor) in this category, with similar models of the lenses mentioned below.
The Rokinon 14mm F/2.8
If you were to ask me for advice on “the best budget lens for astrophotography”, I’d lean toward the Rokinon 14mm Ultra Wide Lens if you plan on shooting wide-angle astro-landscapes. I don’t have any photo examples using this lens (yet!), but it’s a relevant part of the conversation.
For a look at some example photos of this lens used for Milky Way photography, be sure to check out this review by lonelyspeck.com.
The Rokinon 14mm F/2.8 Lens attached to my Canon DSLR
At 14mm, the Rokinon is a much better choice than the Canon 50mm if you plan to capture large areas of the night sky, including the Milky Way. With a full frame camera, the ultra-wide 14mm FOV can be fully appreciated.
Interestingly enough, I used the Rokinon lens to film most of the video I recently published. The wide field of view comes in handy when shooting scenes of my equipment underneath a starry sky.
- Ultra Wide-Angle (Especially using a full-frame DSLR)
- Fast Optics (F/2.8)
- Manual aperture adjustment
- Manual focus ring is slow
- Big and bulky objective lens
As the season changes, I’ll spend much more time with this astrophotography lens. I am curious to see how much sky I can collect in some stacked long exposures.
The Canon EF 50mm F/1.8
This lens is about $150 brand new, is virtually weightless, and is useful focal length for wide field imaging on certain targets. I purchased the Canon EF 50mm F/1.8 lens years ago, as it added a much need portrait lens to my DSLR kit at the time.
With the aperture wide open at F/1.8, you can pull in a lot of light in a short period of time, but the stars are a little rough at the edges of the frame. If you stop down to F/2.8 or F/3.2 things improve dramatically.
- Extremely Affordable
- Fast Optics (F/1.8)
- No Image Stabilization
- Impractical Focal Length
- Stars at F/1.8 aren’t great
Using a Clip-in DSLR filter with a camera lens
To make life easier, I opted to use an h-alpha filter in the T3i to completely ignore the light pollution from home. The Astronomik 12nm Ha filter clips into my camera – and isolates the hydrogen gases found within the hunter.
The Astronomik 12nm Ha Clip-In Filter used for my Narrowband image of Orion
The clip filter fits nicely underneath a camera lens like the Canon 50mm F/1.8. One of the reasons I like clip-in camera filters so much is the flexibility of using them with an astrophotography lens or telescope.
The Orion Constellation at 50mm (in narrowband ha)
The following image is of a large portion of the night sky including the stars and nebulae surrounding Orion.
The resulting narrowband image is, of course, black and white – with the red channel isolated in photoshop for processing. For more details on processing images in ha from a DSLR, have a look at my narrowband Photoshop tutorial.
Barnard’s Loop in Orion | 26 x 3-minutes @ ISO 800
Overall, I am quite pleased with the way this turned out. The total exposure time was short, and the sky conditions were lousy. However, the focal length of the Canon EF 50mm lens was spot on for this target.
I have never shot Orion at this focal length before in narrowband. Seeing Barnard’s Loop appear on the camera display was a huge thrill!
My individual RAW exposures in narrowband ha – they’re all red!
The shots were 3 minutes each, at ISO 800. I stopped the aperture down to F/3.2 to sharpen things up, not to mention not blow out my 3-minute subs.
As you can see, the stars are still rather sharp at the very edge of the field.
A sound polar alignment on the little iOptron SkyTracker was all I needed for sharp, pinpoint stars for each 180-second sub. Can your telescope mount go 3 minutes unguided with sharp stars?
To polar align, I simply refer to my Polar Finder phone app and make the necessary adjustments to the mount.
At this focal length, autoguiding is not necessary and the field of view is quite wide and forgiving. With that being said, I am so impressed with the smooth and accurate tracking on the SkyTracker.
Camera Automation and Focus
I automate my imaging sessions on the mini-rig using a remote shutter release cable. I set everything from the number of exposures to the individual exposure length.
My cheap Polaroid Remote Shutter Release Cable
The cheap Polaroid version I bought on Amazon has been surprisingly reliable. Using the remote, I let the camera do it’s thing until it’s time to tear down and go to bed.
I feel less guilty about tearing down under clear skies when using a camera lens rig like this – I’m not sure why.
Quick and Efficient Backyard Imaging
For me – finding ways to sustain this hobby long term is important. This rather brief astrophotography session provided me with enough data to produce an impressive portrait of Barnard’s Loop, and the Orion constellation in hydrogen alpha.
The simplicity of mounting the camera on a small tracking mount and walking away really appeals to me. On frigid February night, it’s a refreshing experience that doesn’t involve a lengthy star alignment routine or lugging 40 pounds of gear around.
Shooting deep sky through a telescope will always be my bread and butter, but shooting with a cheap astrophotography lens on a small star tracker sure is a lot of fun too.