Examples  

Some examples using AstroStack



(click on the thumbnails to see the full picture)

Have a look at what the picture is hiding from you.

Moon before and after Moon straight wall

Left picture: shows how 60 video frames look when combined and aligned.
Right picture: shows what unsharp masking and deconvolution can do.



The difference between using some pictures and using as many as possible.

Improving on Saturn Saturn

Left picture: from one of the original video frames.
Middle picture: compiled from a few video frames aligned by hand.
Right picture: shows how combining almost 200 video frames now reveals a hint of the Cassini division.
(all pictures where resized to give them the same size)

Saturn is a difficult object, because the video module works at the limit of its sensitivity, leaving the video recordings with a lot of noise.



Why enlarge pictures before using them?

The effect of enlarging Mars (15 April 1997)

This shows you the effect of enlarging (or resizing) before aligning pictures
Left picture shows Mars taken from a video, aligned and combined with AstroStack, then enlarged 3 times with a graphics program.
Right picture shows Mars taken from the same video, enlarged (resized) 3 times, aligned and combined all within AstroStack.
You see that resizing in the very beginning (i.e. the preview stage) gives potentially more detail or a more appealing picture.



The sense in having a (slightly) moving object.

Moving objects and resolution

This example shows the benefit in having a moving object, instead of holding it deadstill.
Left picture: Object held still in front of a video camera. Enlarged 2 times, auto aligned and combined pictures, then using unsharp mask to show details.
Right picture: Object handheld, moving slightly, in front of a video camera. Same procedure.



What use is a flatfield?

Flatfield demonstration

This example shows the capabilities of a flatfield for removing spots and irregularities on the camera screen. It was shot with a second hand video camera equipped with an image intensifier tube, showing blobs and smears probably because of ageing.
Left picture: the result from the original video, not much to look at.
Middle picture: the flatfield, produced by holding a white piece of paper in front of the camera, keeping everything else the same.
Right picture: the original video which resulted in the left picture, now corrected with the flatfield. This isn't perfection, but without flatfield it is quite useless.