When it comes to astrophotography there are two camps, Planetary Cameras for taking pictures of the Sun, planets, and moons, and Deep Space Cameras for taking photographs of the faint objects like nebulae and galaxies. Both camera types are specifically designed for each type of astrophotography and they couldn't be any more different.
Planetary cameras are some of the easiest to use and will work with almost any telescope. If you are new to astrophotography this is a great place to get started because it doesn't take long to get good results.
Planetary cameras work by taking advantage of the brightness objects they photograph. The Moon, Jupiter, and Saturn are brighter compared to other objects like nebulae and galaxies and to photograph these objects, very short exposure durations are required. Planetary cameras shoot high-speed video at rates as low as 15 frames per second to as high as 738 frames per second! The goal is to capture as many frames as possible where the atmosphere is most stable. Once the video is recorded, software analyzes the good video frames from the bad, then averages out the information of the good frames, leaving you with the sharpest image possible.The main advantages are:
- Planetary cameras are relatively inexpensive.
- They can be used on almost any telescope system. (Including telescopes with Alt-AZ Mounts).
- Recording lasts no longer than two minutes, so one can start editing images quickly.
- Planetary camera accessories are also inexpensive and often work with eyepieces.
- Most planetary imaging and processing programs are free!
- The bigger your telescope is, the more resolution you get.
The only downside when it comes to planetary imaging is that you are often limited by the number of objects that you can photograph.
Deep Space Cameras
Deep space cameras are engineered to record the faintest details. They produce the most stunning images of the night sky and are often used in astronomical research. To capture the rich color of nebulae or the dim structures of galaxies, a deep space camera is hands down the best tool to use.
Unlike planetary cameras, deep space cameras are used to take long exposures to capture every photon possible. These cameras can take exposures lasting up to 30 minutes or longer! Since long exposures build up heat and heat creates image noise, these cameras come with cooling systems to bring the sensor below freezing temperatures. Deep space cameras are used to maximize tonal detail by recording brighter whites and darker blacks better than other camera systems like DSLRs or smartphones. Even with all this technology, the objects that deep space cameras photograph are so faint, one shot will not give you enough detail. Multiple images are taken of the same object and averaged together with stacking software to further reduce image noise and enhance detail.The main advantages are:
- Most objects in the night sky are found in deep space. There is plenty of objects to shoot.
- They have better dynamic range than other camera systems.
- Offer consistency so images can easily be calibrated compared where other systems can't.
- Images will be sharper than DSLRs, or smartphones.
- These cameras provide the best image quality of the night sky possible.
Some things to consider when getting a deep space camera is that you will need to be using an equatorial mount to take exposures longer than 30 seconds and the optics of your telescope need to project a corrected image that will fit the sensor of the camera.