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To explore the many other features of Registax and view helpful tutorials, go to the Registax
homepage at: http://www.astronomie.be/registax/index.html
how neximage works
NexImage utilizes a light sensitive imaging sensor to capture streaming video of any solar system
object. This video can easily be viewed as hundreds of individual images (frames) that can be
digitally stacked to significantly reduce the electric “noise” inherent in video chips and bring out the
unseen fine detail (signal) hidden within your image. The NexImage camera takes advantage of the
fact that the signal to noise ratio of your stacked composite image is proportional to the square root
of the number of frames combined. This means that stacking as few as 16 frames will reduce the
grainy noise of the composite image by 4 times. While stacking as many 900 frames will improve the
image by 30 times! However, stacking the individual frames is only half the power of the NexImage
imager. With the included software package, each individual frame is analyzed for quality to filter
out those frames most affected (blurred) by poor atmospheric “seeing”. This form of after-the-fact
adaptive optics, leaves only the sharpest, clearest frames to be stacked and aligned into a high
quality image. Finally, powerful processing features automatically break the image up into individual
unsharp mask layers that can be used to bring out tremendous detail and reveal final images that
will rival those taken with astronomical CCD cameras costing thousands of dollars.
The Basics
Focusing
As with all astrophotography, sharp focus is essential for high quality results. Although there are
many techniques and devices for focusing your telescope, the human eye still remains one of the
best detectors of subtle changes in detail. One advantage that video imaging has over imaging
with more sophisticated (and expensive) CCD cameras is the speed in which it can display its image.
Focusing NexImage is more similar to focusing an eyepiece than a CCD camera. Unlike with long
exposure cameras you don’t have to wait many seconds to see the effect of a focus change.
