Anyone who has ever taken a group of people out to look at the night sky through a telescope, or perhaps yearned to share the wonders they’re viewing to the world, will love the Atik Infinity. This is a camera that combines astronomical CCD quality imaging with essences of video broadcasting.
This review is of the monochrome variant of the Infinity, though a colour one is available. At the camera’s heart is a Sony ICX825 CCD sensor, which has excellent low noise characteristics.
Designed for relatively short exposures, the Infinity has no active cooling. However, we found its passive cooling to be acceptable for relatively noise free results.
The camera is controlled by a Windows-based program also called Infinity. This is dedicated to the Infinity hardware and is well designed and easy to use. The main controls adjust exposure and binning.
Binning makes groups of pixels work together as a ‘super-pixel’: for example, 2×2 binning groups a square of 2×2 pixels so their recorded values are used together.
This increases sensitivity at the expense of array size, so a 2×2 bin of the Infinity’s 1,392×1,040-pixel sensor effectively reduces its array to 696×520 pixels.
Other binning modes are also available.
There also a ‘finder’ mode, in which the camera performs a short exposure, high-binned loop. The somewhat noisy result is perfect for locating faint objects. When you are centred up, select video mode and you’re all set.
Using a 4-inch, f/9 refractor, we found that finder mode was great for scanning the fainter sections of the Rosette Nebula as well as centring on faint galaxies.
In video mode the camera exposes in a continuous loop, sending two or three full frames to its host computer every second. The Infinity software checks image quality and, if good enough, adds it to a stacked result to produce a cleaner image.
It was mesmerising to watch the way the spiral arms of the Whirlpool Galaxy, M51, became better defined after only a few stacked images.
You have control over the definition of quality and whether you want the results stacked. A session can be recorded for replay if required. If activated, each stack image is individually stored for later access using other processing packages.
Strangely, we found we couldn’t open the recorded FITS files using PixInsight, a high-end processing application. PixInsight apparently didn’t like the FITS header written by Infinity.
The camera’s 16-bit images require processing to optimise them for the computer screen, but the Infinity software makes this task simple via a number of histogram presets.
For example, we found that the bright Orion Nebula, M42, was best shown using a ‘medium’ or ‘high’ setting, whereas faint objects such as the Running Man Nebula (NGC 1977) benefitted from the ‘low’ setting, which stretched out the fainter detail better.
It’s also possible to adjust the histogram manually if required.
The Infinity handles bright targets such as M42 well, but it’s great for the faint stuff too. We loved tracing the faint twists of nebulosity in the outer regions of M42. The Leo Triplet galaxies, M65, M66 and NGC 3628, came across very well.
The dark dust lane running through NGC 3628 was very clear and showed lots of detail via our 4-inch scope. In fact, we found the Infinity’s image quality to be generally excellent. The camera will work with bright Solar System objects, but this is not its strength.
We had to fit a neutral density filter for it to cope with the bright Moon and its 2-3 frames per second wasn’t optimal.
We fitted a wide angle CCTV lens using our own C- to T-mount adaptor. The arrangement worked well, showing a large, deeply exposed area of sky on screen.
The camera body doesn’t have a threaded tripod hole, which is a pity as it’s hard to point without one.
The Infinity has some stiff competition from some of the newer high frame rate planetary cameras daring to venture into the world of deep-sky imaging.
At the moment, its edge comes from its image quality and dedicated control software, which makes group or broadcast outreach sessions really simple to handle.
Infinity control software
The Infinity control software presents an easy interface to get to grips with, essential for sessions where the camera is used for live public viewing.
Perfect for showing deep-sky objects to a crowd of people grouped around a computer screen, the software can also stream to a YouTube live broadcast channel, allowing you to reach an even wider audience.
A recording facility means you can replay part or all of a session back to your audience any time.
Simple image histogram adjustments also make sure you’re presenting an optimised view.
This works well and alleviates complex manipulation you’d otherwise encounter during a live session with typical CCD control software.
The Infinity software can easily zoom and pan into a certain part of an image – great for highlighting what you’re specifically looking at.
It’s also possible to use a duplicate display window which allows you to show the camera’s output on screen without having controls visible around the edge.
This works really well if you have a second screen set up, the secondary display showing the full image while you make adjustments from the primary one.
Atik Infinity monochrome CCD camera: outstanding features
USB 2.0 port
There is a Type-B USB 2.0 port on the bottom of the camera to connect it to a computer. A 2m USB cable is provided for this connection. At its full resolution of 1,392×1,040 pixels, this interface permits 2-3 frames per second to be sent to the host computer.
ST-4 compatible autoguider port
As well as having the ability to detect and present deep-sky objects to a live audience, the camera can also be used as a sensitive autoguider. At the bottom of the body is an ST-4 compatible autoguiding port. A small red LED sits next to the port and illuminates when the camera is performing autoguiding functions.
The Atik Infinity uses a Sony ICX825 sensor embedded with EXview HAD CCD II technology. Quantum efficiency reaches a peak value of 73 per cent at 525nm. The 1,392×1,040 pixels each measure 6.45μm square. Images are 16-bit with a low readout noise of six electrons. This particular chip is also used in the Atik 414EX cooled astronomical CCD camera.
The camera body is metal and rectangular, measuring 110x70x25mm. Its narrow thickness means it can be used with fork-mounted telescopes without fear of the camera hitting the base of the mount. Power is supplied via a 12V socket at the base of the body; a 1.8m car plug-type power cable.
At the front of the Infinity there is a 57mm collar which is internally T-threaded (M42x0.75). At this diameter, the collar doesn’t slot into a 2-inch eyepiece holder, but a 1.25-inch eyepiece adaptor is supplied as standard. The backfocus distance (how far the sensor is behind the collar’s lip) is 13mm.
This review originally appeared in the February 2016 issue of BBC Sky at Night Magazine.