The first camera used in the Starfish competitive camera shootout is a camera that we designated 'CamA'. This camera was designed as a purpose built guider. It is a minimalist implementation that strives to be the absolute lowest cost guide camera available to the end user. As such, the designers have met their design goals. This camera sells direct from the USA distributor for $270.00 and as such is the most inexpensive camera in the group tested.
In order to achieve such a low cost, however, the designer has made a conscious decision to cut corners in a couple of key areas. First of all, the camera digitizes the image pixels to only 8-bits. Second, and more importantly, the camera's read noise is more than twice as high as that of the Starfish camera. Since both cameras use the same Micron image sensor, this has to be due to the design of the camera's electronics interfacing to the image sensor.
Because of the lower S/N of the images from this camera, the Starfish camera is able to provide better guiding and on slightly dimmer guide stars than CamA.
In our tests of the pulse guide outputs from CamA, we noticed a peculiar time offset added to each guide pulse. This amounted to approximately 10% guide pulse errors in our pulse tests.
CamA is slightly smaller and lighter than the Starfish camera. It also costs quite a bit less. However, the Starfish camera has better image quality and more accurate guide pulse command generation.
The Starfish also has some features not available on the CamA camera. Features such as integrated image buffer, dedicated hardware image processing, guider status LED's, RS-232 interface port, TEC cooling and broader software support with the Mac OS X operating system being supported. Also, because of the superior quality of the images, the Starfish camera can double as an imaging camera for planetary imaging as well as for brighter deep-sky objects. |