The StellaCam II is an excellent introduction to Deep Sky imaging for those who appreciate the versatility of a ″True″ video camera. The output of the camera can be displayed on a TV, VCR, Monitor.
The On-Screen (Monitor) image of brighter objects Messier objects such as the Dumbell Nebula rivals processed CCD images. The views on the monitor are spectacular. This improvement makes the StellaCam II especially well suited for school, planetariums, college, universities and industry and both the beginning imager and advanced imager.
There is a separate remote control box for slow shutter speed (frame accumulation), gain, gamma (contrast) control and freeze frame.
The freeze frame button will freeze your on screen image on the monitor. This is useful when you have an image you want to describe or display for a large group. Once the screen image is frozen, the telescope can be slewed to the next object while a discussion is being a given for the current on-screen image.
Following are two quotes from Sky and Telescope Oct. review:
″AVA′s latest offering for deep-sky video work is the StellaCam II. ... , but it can stack twice as many frames allowing it to probe deep into the night sky. ... it not only produces a deeper image but also delivers one with far better tonal quality and less electronic noise.″ - Johnny Horn, Sky and Telescope
″Although, StellaCam II is more expensive than its predecessor, .... it offers extremely compelling views of deep sky objects. In some cases it even produced images comparable to those shot with low-cost astronomical CCD cameras, but without the fuss of image calibration.″ - Johnny Horn, Sky and Telescope
The StellaCam II System includes, Camera, Hand Control Unit, 25′ Shielded BNC to RCA Video Cable, 110 Volt Power Supply, C - 1.25 Inch Adapter, Instructions, One Year Warranty.
″True Video″ System for the maximum in versatility - Monitor display, auto-guiding, computer image capture and image processing, etc..
Excellent Dynamic Range (allowing very faint details to be captured)
External control box for Manual control of Shutter Speed, Gain and Gamma.
Very small size
Camera runs cool - preventing in most instances, the buildup of warm pixels.
Very smooth and even background with gain and gamma set at midlevel
Excellent ″LIVE″ picture that is very comparable to a 10 second cooled CCD camera image.
The StellaCam II Technology optimizes the use of the Non Ex-View SONY HAD CCD. The choice of this CCD results in an image of very low noise and very few hot pixels. The combination of the very low noise of the SONY CCD with very low noise electronics in the StellaCam II results in an marked improvement in signal to noise (S/N) ratio. This improved S/N ratio enables the StellaCam II to reach 18th magnitude in an eight inch telescope. The images are very clean at midlevel gain and gamma settings. The views are so impressive compared to the visual views that it is like have a telescope 5X larger in aperture!
The 256 frame accumulation combined with internal camera electronics that are very low in noise results in an extremely sensitive camera. Objects like the Veil Nebula, Cocoon Nebula, Andromeda Galaxy Dust Lanes can be easily captured.
Requirments for Operation of Camera:
A moderately accurate drive; capable of making 8.5 second (NTSC-USA) to 10.24 second (PAL-OVERSEAS) exposures
Moderately accurate polar alignment.
Monitor, TV, VCR or Camcorder to view, capture or record images.
110 volt or 220 volt mains power supply. OPTIONAL 12 volt power cable available.
Use of a computer to capture and process images via optional frame capture cards (Imperx, Flashbus MV-Lite) and image processing software. (Astroart, Maxim CCD, K3 CCD Tools & Registax)
To take advantage of the full resolution of the CCD chip in terms of computer captured images, we recommend the Imperx Laptop PCMCIA capture card and FlashBus MV Lite PCI Desktop Capture card. (Be careful if you are looking at inexpensive USB capture systems, as most of the low cost systems capture in only a 320x240 resolution mode. This will only give you a very small postage stamp image size image on the computer screen.)
To take full advantage of the sensitivity of the camera a fast optical system is recommended, ie. an F/3.3 or F/4 system will perform much better than an F/10 system and will place less demands on the accuracy of a mount. Hyperstar and FASTAR Secondary replacement optical systems should work with the proper adapter. We recommend the OPTEC f.3.3 NextGen focal reducer system as it can be easily adapted for color imaging via the unique pin registration system.
Operation of Camera:
The operation of the video camera is very simple. The video signal output on the back of the StellaCam II is a composite video signal via the BNC connector on the back of the camera. A 24-25 foot 75 ohm shielded video cable is supplied with the complete system. A RCA connector is supplied on the output side of the cable. (optional longer video cables are available) The BNC connector on the video cable is push fitted onto the back of the camera and then twisted until it locks in place.
The RCA output connector from the camera goes into any RCA VIDEO IN jack on a camcorder, television, vcr, monitor, frame grabber etc..
A 110 volt or 220 volt to 12 volt DC power supply is also included. The wall transformer will supply power to the camera. Optional 12 volt power cords are available. The 220 volt or 110 volt is plugged into the mains power supply and then plugged into the lower right hand side connector on the back of the camera.
The external remote control box is plugged into the back of the camera via the 12 pin hirose connector. You must be careful when plugging in this connection so as not to break off any of the small pins. IT IS RECOMMENDED THE CONTROL BOX BE PLUGGED IN BRIGHTLY LIT CONDITIONS. DO NOT ATTEMPT THIS IN THE DARK AS ANY MISHANDLING AND SUBSEQUENT DAMAGE WILL RESULT IN A COSTLY REPAIR.
The Remote Control Box has four functions:
The first is the Slow Shutter Speed Frame Accumulation Mode. This is the timed exposure setting for the camera. This accumulation of frames acts as a slow shutter speed mode for the camera. The frames are co-added within the camera permitting exposures of up to 8.533 seconds for the NTSC model and 10.24 seconds for the PAL model. The OFF setting on the control box is the standard video shutter speed of 1/60 second (.017 second) for NTSC (EIA) frame and 1/50 second (.02 second) for CCIR (PAL) frame. Setting 1 is one frame added to the orginal frame etc. .
The next function is the Gain Rheostat. The manual gain control has settings of 8-38dB. 8 corresponds to the lowest gain setting and 38dB corresponds to the highest gain setting. The midlevel gain is near 18 dB. For most applications you will not have to go beyond the mid level gain settings. As you increase the gain setting the sensitivity of the camera increases. The noise in the image will also increase as the gain increases. The goal is to keep the gain as low as possible and still have a high quality image on the screen. Higher gain settings can be used to isolate a particular feature in an object that would otherwise be invisible at lower gain settings.
The next function on the control box is the Gamma setting. Gamma relates to contrast. There are three gamma settings .35, .45, and 1.0.
The Red Button on the side of the control box is the Freeze Frame Button. By pressing the freeze frame button once, the image on the monitor will be frozen. It will not change. This allows the imager to select the best possible image. This is useful for explaining features in an object to a group. Pressing the button again will star the normal rate of video frame capture again.
|Auto Iris||A.E.S. / VIDEO Type Lens|
|Broadcast System||AV-STCAM-II EIA AV-STCAM II -PCCIR|
|Fram Accumulation||MANUAL CONTROL BOX - 1, 2 TO 256 FRAMES|
|Gain Control||AUTOMATIC / MANUAL GAIN 8-38dB|
|Gamma Correction||0.35, 0.45, 1.0|
|Image Sensor||AV-STCAM-II EIA SONY ICX418ALL.pdf AV-STCAM-II-P CCIR SONY ICX419ALL.pdf|
|Manual Frame Accumulation Shutter||The OFF setting on the control box is the standard video shutter speed of 1/60 second (.017 second)
for NTSC (EIA) frame and 1/50 second (.02 second) for CCIR (PAL) frame. Setting 1 is for one added frame etc.
|Minimum Illumination||STELLACAM II 18TH MAGNITUDE DEEP SKY IMAGING WITH 8 INCH TELESCOPE 0.00002 lux at F/1.4 Planetary -
1/60 sec ONLY ( see limitations section below ) Integration (Deep Sky) mode - UP to 256 Frame accumulation
for a 8.5 second NTSC 10.8 second PAL exposure
|Operation Temperature||-20C TO +50C|
|Operational Humidity||WITHIN 85%|
AC100V, 220V CAMERA POWER REQUIREMENTS DC10.2-13.8V 50/60Hz DC+12V Power supply weight Approx. 236g
|Resolution||600 TELEVISION LINES|
|Scanning System||525 LINES 60 FIELDS/SECOND NTSC 625 LINES 50 FIELDS/SECOND EIA|
|Signal to Noise Ratio (S/N Ratio)||52 dB|
|Sync System||INTERNAL / VD - LOCK (OPTION)|
|Weight||Camera weight 150 grams|