Altair Hypercam 183C Review
Thanks to my friends at OTA, a brand new Altair Hypercam 183C arrived at my door last week. The striking purple exterior color of this one shot color CMOS camera makes a bold statement, but it’s the deep sky imaging capabilities of the cooled sensor that have captured my attention.
There are many options available for deep sky astrophotography these days, and traditional DSLR images such as myself are left with some tough decisions. One look at the data captured using a cooled CMOS sensor, and you will notice the astonishing difference this can make.
In this post, I will share 2 deep-sky photo examples using this camera with my ED102 telescope. Please keep in mind that these images were captured in heavy city light-pollution. Under darker skies, the Hypercam will perform even better.
A cooled color CMOS camera for deep-sky
The ExmorR rated back-illuminated sensor is touted as being one of the most important factors when comparing this camera to a DSLR. The internal fan keeps this camera cool, and the low read noise qualities mean that the Hypercam 183C should blow my Canon 600D out of the water in terms of noise.
In my early test with this camera, I was astonished at just how cool this sensor was during an imaging session. There is no temperature readout on this chip, but the difference is obvious when reviewing the images I’ve captured.
The CMOS sensor size in this camera is 16.05 x 12.61mm, which Altair Astro says is well suited for my F7 refractor telescope. This camera is a new breed of astronomy imaging cameras designed to tap into the image quality benefits only previously experienced when using a CCD sensor.
The Hypercam is worth a look for those looking to upgrade from a DSLR or start their journey into astrophotography on the right foot. My testing will specifically focus on the deep sky imaging aspect of this camera.
Altair Hypercam 183C Features:
ST4 autoguiding port
Internal Fan Cooling
12Bit RAW mode
Built-in UV/IR filter
Built-in Amp Glow Reduction
Fans of DeepSkyStacker will be happy to know that you can, in fact, register and stack the .FIT files produced by this camera in DSS. Using the 12bit RAW color space means ultra high-resolution 16-bit full-color RGB image to dive into when image processing. More on this below.
Video: Let’s Photograph the Dummbell Nebula
In this video, I get nostalgic about one of the first deep sky objects I ever photographed, the dumbbell nebula. You’ll see the Altair Hypercam 183C in action as I use it to capture exposures on M27 from the backyard.
Below, I’ll share my thoughts on the image quality of my Dumbbell Nebula image used in the video. This experience should provide you with a good idea of what to expect when using the Altair Hypercam 183C.
Deep Sky with No Autoguiding?
Short-exposure “lucky imaging” is an attractive choice for beginners. Early on, one of the toughest aspects of astrophotography a capturing a long exposure image with steady tracking. Obtaining sharp stars on an image longer than 2 minutes may seem impossible.
Short exposure imaging on mounts that are not using autoguiding is an attractive option. The Hypercam 183C is a new breed of imaging camera that aims to produce incredible images by stacking many (really) short exposures to improve the signal-to-noise ratio.
Most modest entry-level astrophotography mounts (My Sky-watcher HEQ5 included!) such as the Celestron AVX and Orion Sirius are capable of exposures up to 1 minute without autoguiding. So, with a highly sensitive camera like the 183C, it may be possible to obtain impressive results my stacking many short exposures.
This is something that just isn’t possible with a standard DSLR camera. When the ISO is pushed too far, the thermal noise in the images begins to take over. With no cooling option, a DSLR sensor can reach scorching temperatures that make image processing a nightmare. (trust me on this one)
Here is an example of short-exposure deep-sky imaging using 10-second exposures on a very bright deep-sky object from Nick at Altair. The Orion Nebula using the Hypercam 183C.
Imaging and Guiding with Altair Astro
The Hypercam 183C threaded nicely into my 2″ Altair 08.X Flattener/Reducer. The camera is compact and lightweight, meaning my overall astrophotography imaging train continues to put very little stress on the mount.
I did not need any additional adapters to connect the camera to my telescope focuser. I used an Allen key to remove the threaded ring with a 1.25″ opening above the sensor. Once that ring was removed, I was able to screw my field flattener into the 183C directly.
An extension tube was needed to reach focus with the new Altair camera. So, although the imaging configuration is lighter and less obtrusive than my Canon DSLR, it is longer overall. This is something to watch during un-monitored imaging sessions where a crash into the mount may occur.
From a visual gear perspective (Something I have never put too much attention on), the matching purple Hypercam 183 and GPCAM2 look rather attractive. My deep sky imaging rig gets used too much to stay clean and polished. My rusty counter-weight on the HEQ5 is proof!
Camera Control Software
One of the major factors involved with purchasing a new astrophotography camera is the considering the new software and drivers required to run the unit. In the case of the Hypercam 183C, I had three options for camera control out of the box:
I haven’t spent too much time with AltairCapture yet, so I decided on SharpCap Pro to control my imaging session. Up until now, I used SharpCap for framing and focusing using the ASI071MC-Cool and to aid with my Polar Alignment process. I had never controlled a full deep sky imaging session from start to finish until recently.
As I am sure many of you have experienced, my first night using a new software for deep-sky imaging was full of “ah-ha” moments that eventually resulted in a better understanding of the software.
I believe that SharpCap has the potential to be a solid choice for long exposure deep sky imaging sessions, even if it feels tailored for the planetary and EAA crowd. The always-refreshing image preview that starts as soon as your camera is selected can be off-putting and confusing for DSLR imagers.
I was able to overcome most of my issues after some quick investigating online. Unfortunately, one issue that remains is an unexplained “frame dropping” that causes my images to not be recorded onto the computer. The team at SharpCap is aware of the issue and offered some great troubleshooting options to help me out.
Update – The issue had to do with the USB port I was using on my aging laptop. Switching ports corrected the issue!
Deep Sky Image Example
Limited to short exposures using SharpCap, I managed to capture 37 image frames at 60 seconds each on the Crescent Nebula. The imaging conditions and limited exposure time resulted in a poor rendition of NGC6888, but the image quality of the Hypercam 183C is evident.
Here is a close-up of an area in the image that shows the smooth details captured by the Hypercam. The star color is rich and beautiful using this CMOS One-shot-color sensor.
In this review, I really wanted to produce an image using several long exposure image frames (of 3 minute or more) to portray the true potential of this camera. Unfortunately, software bugs and weather did not coordinate. The image below is less than 1 hour’s worth of data using short 1-minute exposures.
To make matters worse, I accidentally used an external UV/IR luminance filter while imaging. I guess I forgot to read the full specification sheet for the Hypercam 183C and discover that it has a UV/IR filter built-in!
Test Image – Hypercam 183C (37 Minutes)
I have attempted to keep this data mostly raw, and have applied very little image processing at this stage. A basic curves adjustment, levels, and gradient removal were used to show off the image quality when using the Altair Hypercam.
Click the image for a larger version.
Total Exposure: 37 Minutes (37 x 60″)
Again, I can’t stress enough that this image is an example of the low noise qualities the image frames. I could pull out much more nebulosity in the DSO using Photoshop, but that would not illustrate the aspect of the data I am referring to in this post.
This image includes much less exposure time than I would normally shoot. In retrospect, it was not a great test subject as the NGC 6888 requires OIII and Ha data for a complete structure. Regardless, this image represents overcoming the challenges involved with a new camera and imaging software early on.
Long Exposure DSLR version (6 hours)
We’re not comparing apples to apples at this point. I have only been able to test the individual image quality and noise characteristics of the 183C thus far. For comparison purposes, here is the Crescent nebula in HaRGB using my modified DSLR and almost 6 hours worth of data.
RGB Total Exposure: 2 Hours, 45 Minutes (55 x 180″)
Ha Total Exposure: 3 Hours, 4 Minutes (37 x 300″)
The difference is that the overall image quality is actually much better in the images shot using the 20MP Hypercam 183C. With enough exposure time, I could produce a much higher-resolution version of the Crescent Nebula. I would have to include data in h-alpha with the Altair camera as well, of course.
Overall, I am extremely impressed with the Hypercams deep sky image quality. The background sky was smooth and free of virtually any noise. Processing the image in Photoshop was a pleasure thanks to the smooth, detailed image produced in a relatively short integration period.
For my second test, I pushed the IMX183C sensor to its limits…
M27: The Dumbbell Nebula
The deep sky object of my first APT test was the ever so bright and satisfying dumbbell nebula. I often recommend trying M27 early on in your astrophotography ventures as this planetary nebula comes in at a whopping magnitude 8.1.
On July 5th, the 91% illuminated moon was bright, and the air was hot. These conditions do not bode well for long exposure astrophotography using a DSLR camera. My hope was that this would be a great time to test the low noise qualities of the Hypercam.
Total Exposure: 1 Hour, 20 Minutes (40 x 120″)
Why is it so noisy?
There are several reasons why this image of M27 is rather noisy and “crunchy” compared to my other images.
Gain set too high
I believe the biggest contributing factor was the dangerously high gain setting used throughout the session. I wanted to push the limits of the Sony IMX183C sensor, and I think I pushed it a little too far. On a cold imaging session during the winter this may have worked, but not in the middle of summer!
Imaging under a full Moon
Secondly, imaging under a full moon without the use of filters means a general lack of contrast and surface detail when capturing a deep sky object like a nebula. Pulling the details of M27 forward while taming the background sky glow drastically increases the overall image noise.
Exposure time / light pollution
1 hours worth of data under these conditions is hardly enough to compensate for a bright city sky. Deep-sky imaging in the city without a light pollution filter means collecting a lot of unwanted light in your images. This translates to a difficult image processing situation afterward where much of your time is spent balancing the colors of a red/green night sky.
Hypercam 183C Settings and Tips
Here are some helpful pointers for getting up and running your first night out with the Hypercam 183C. I would recommend using SharpCap to control this camera, as it is much more stable. However, so of you may prefer to use APT, and this advice may save you some frustrations.
Using the Hypercam 183C with Astro Photography Tool
These tips will come in handy only after you have installed the required drivers and Astro Photography Tool has successfully discovered the Hypercam 183C via the ASCOM properties.
- Connect your guide camera first, and make sure it is functioning properly. In my case that was the Altair GPCAM2 in PHD2.
- Use SharpCap 3.0 to frame and focus your imaging target. The highly sensitive imx183 CMOS sensor makes focusing with a Bahtinov mask ultra responsive and accurate. The same goes for framing your object. Crank to gain up and, and you’ll often spot your DSO in a 4-8 second exposure.
- Start your imaging plan with a”fresh connection”. Disconnect the camera on start up, and shift click the connect button. Choose the Hypercam in the camera selector, and confirm your gain setting, and that the fan is turned on!
Without re-applying this step before each imaging sequence, sometimes the sequence would get stuck on the first frame (“busy”).
Debayering in Deep Sky Stacker
The image frames were shot in .FITS format, using the RAW12 color space in SharpCap. It is worth noting that Deep Sky Stacker will only debayer 16-bit FITS files. I shot 8-bit files in a previous session and was unable to get color in my stacked image.
The Hypercam 183C uses an RGGB Bayer pattern, which is useful to know when getting ready to register and stack your images.
Whether you are using APT or SharpCap to control the camera, it is imperative to select the full RAW12 color profile mode to ensure you are recording the highest quality image data.
Using Astro Photography Tool
After some minor software issues, I am happy to report that the Hypercam183C works well with Astro Photography Tool. This is big news if you are accustomed to applications like BYE or SGP for camera control.
Astro Photography Tool has proven to be a capable and reliable tool when used with a color CMOS camera such as the ASI071MC or Altair Hypercam 183C.
The team at Altair was quick to provide support when I ran into trouble. Once the issue was addressed, an update to the Altair ASCOM driver was made and the 183C responded positively in APT.
The Altair Hypercam 183C shows the potential to outperform a modified DSLR camera for deep sky imaging. The sensor cooling fan is the single biggest advantage, along with a slew of other astronomy-specific qualities.
The added conveniences such as better focusing and complete chip sensitivity control are aspects that are only appreciated after several imaging sessions. With an understanding of the SharpCap camera control software, you are well on your way towards countless beautiful deep-sky images with the Hypercam.
It is a shame that much of my time with the 183C was spent tackling early software bugs and not capturing deep-sky images. This resulted in an example image of the Dumbbell Nebula that does not show the true potential of this color CMOS camera.