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Focusing Tips
To achieve best focus, concentrate on a high contrast feature of the object you are imaging.
Focusing on small features such as a moon's shadow on Jupiter or Cassini's division in the
rings of Saturn will guarantee best focus across the entire image.
Once the frames of your video are stacked, the overall brightness of the composite (stacked)
image is usually brighter than its individual component frames. For this reason, it is best to keep
the brightness of the video image seen on the screen dimmer than you would normally desire. It
is important that no part of the image is overexposed to assure the maximum amount of detail
in the final composite image.
Collimation
No matter what type of telescope you image with, poor collimation (alignment of the optics) will
ruin your chances for a good image. Before you begin imaging, always check the collimation of
your instrument and make adjustments if necessary. Refer to your telescope's owner's manual
for instruction in collimating the optics.
Finding Objects
At first it can be difficult to locate individual planets due to their relative brightness. To make it
easier to initially find your object in the imaging window, increase the brightness and gain controls
on the Exposure toolbar. This will allow you to better see the object as it passes through the
imaging window. Once you have located and centered the object, you can adjust the setting
until the object is at the desired brightness and contrast.
How long to take Streaming Video
At first you may think that the more frames you record, the better. However, there are some
limitation to the duration of video and the amount of frames you can acquire. Resolution and
file size can both limit the length of time of your video.
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Since the NexImage will combine as many sharp frames as possible to achieve one high-quality
image, you don't want to take so many images that you start to detect the rotation of the planet,
especially on Jupiter which makes one complete rotation in under 10 hours!
Individual frames of a high-resolution video can have large file sizes. Hundreds of these frames
can quickly consume an entire hard drive. We recommend saving your video data onto a CD-ROM.
This way, you can have a library of files stored for processing without consuming hard disk space.
Autoguiding
Your NexImage Burst can be used as an autoguiding camera when used in conjunction with
an off-axis guider or piggyback guidescope. NexImage is compatible with many autoguiding
software such as MetaGuide (www.astrogeeks.com/Bliss/MetaGuide), and a guider port
interface such as GPUSB from Shoestring Astronomy (www.store.shoestringastronomy.com).
SPECIFICATIONS:
Sensor
1/3-inch format Aptina AR0132AT CMOS
Camera Resolution
1.2MP (1280 x 960)
Sensor Size
4.8 mm x 3.6 mm
Pixel Size
3.75 mm square
Sensitivity
5.48 V/lux-sec (@550 nm)
USB Cable
High-speed USB 2.0 cable
Back focus with
13.1mm
nose piece
Back focus from
10.6 mm
threads
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