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Canon EOS5D 100-400mm lens @ 400mm 24 x 20s f/8 ISO3200 2008:01:10 20:45:13 - 20:54:53
My photos since 19th December 07 have been taken with the camera mounted by itself on a HEQ5 motorised equatorial mount. This is definitely showing benefits.
The blueness of this photo (and most of mine) is because it was taken through suburban light pollution and therefore more background red has been removed than any other colour during GRIP's processing. It is always difficult to photograph the true colour of astronomical objects.
The points on the brightest star at the bottom (44 Ori, magnitude 2.75) are an artefact from the camera, thought to be due to diffraction from the iris blades in the lens. Stars visible in the photo go down to fainter than magnitude 14. That is, about 1/1500th of the brightness of the faintest stars visible to the naked eye.
Below is the same portion of the first frame of the 24 that were combined by GRIP to make the image above. It is very noisy because it was taken at ISO3200 and the sky is red from local street lights. Comparing this with the result above shows quite clearly that the automated astro-process in GRIP has a really useful effect.
Canon EOS5D 100-400mm lens @ 400mm 20s f/8 ISO3200 2008:01:10 20:45:13
The next image was through a Meade ETX-125 Maksutov-Cassegrain telescope. The camera was attached by a T-mount at the prime focus, so the telescope was acting as a 1900mm lens with 125mm aperture (so photographically f/15). The telescope was on an HEQ5 equatorial mount driven to follow the stars. The mounting arrangement can be seen here.
37 images have been combined by GRIP to make this photo. This time the nebula nearly fills the whole frame, whereas the non-telescopic examples above were 1:1 croppings from the centre of the frame. So now I have obtained something which is printable at a decent size.
Canon EOS5D Meade ETX-125 37x20s f/15 ISO3200 2008:01:16 20:22:54 - 20:39:51
I think I next need to concentrate on accuracy of focus. This is always difficult with faint objects in a small camera viewfinder.