My telescope came without eyepieces, but can handle eyepieces in the 24.5 mm (0.965 inch) diameter, so it readily accepts the microscope eyepieces I have with 23,3 mm (0.92 inch).
In the spirit of the 5€ telescope I used a small and cheap point&shoot (Canon A800), which I held by hand to the eyepiece. A small camera can be held directly to the eyepiece to easily make images.
The camera was "modded" with CHDK, which makes it possible to set all kinds of things to manual (like exposure). But CHDK is a pain in the ass to use – it is written by people who couldn't care less about user interface it seems. Seriously, you can set "Disable Overrides" to "Disable" and "Off" - WTF????
Don't know yet how these eyepieces will do with nighttime stars instead of daytime sculptures – but here are some daytime images for your pleasure:
My f=700mm telescope with different eyepieces (larger image)
I tried to keep the images consistent (same exposure, same focus, etc.), but couldn't quite manage it... I haven't yet managed to switch off autofocus, so I had some focus problems. Especially the image of CZJ 6,3x is out of focus due to camera problems, but the telescope/eyepiece was focused.
The "No Zoom" images were all made with f=37mm (Full-frame equivalent), 1/500 second exposure and f/3.0 aperture. The "3.3x Zoom" images were all made with f=122mm (Full-frame equivalent), 1/250 second exposure and f/5.8 aperture.
With this fixed exposure/aperture/focal-length one can see nicely the differences in brightness. Especially the Spindler 25x is darker – with the eye (or with longer exposure) the image by the Spindler 25x is bright enough though.
The Spindler 25x with proper exposure (but decisively unproper focus…)
A hand-held Canon A800, a 700mm telescope and a LOMO 15x ocular
– who needs expensive DSLR telephoto lenses?
I will probably not use the Noname 6x and the CZJ? 15x, as they don't seem to offer any advantage. The wide-field of the LOMO 15x is really apparent, it has nearly the same actual FOV as the CZJ 6x. Though finding the Moon was much easier with the CZJ 6x than with the LOMO 15x. BTW: The FOV of the Spindler 25x is bigger than what the camera can capture.
Let's see how it will do with some night sky – but again not tonight, as it is overcast here…
Addendum:
One thing I noticed during the daytime is that in low power (e.g. f=40mm eyepiece) one can almost "see" the spider/secondary, which causes a sort of "shadow" in the middle of the image (one can see the spider/secondary once one steps away from the eyepiece). Here is what I found (about a different telescope):
The StarBlast is not a very desirable scope for terrestrial observing: first, its image is upside down/reversed (common for astronomical scopes); and second, it won't focus close-up. Furthermore: during the day you are very likely to see a vague shadow of the secondary mirror in the field, at low power; this disappears at night when your eye's pupil opens up, within the proper "exit pupil" range. Normally the StarBlast works easily at the maximum dark adapted eye entrance pupil (in fairly young folks) of 7 mm, using about a 28 mm focal length eyepiece (16x, at 3.6 power per inch of aperture). One might be tempted to use a rather commonplace and easily available 40 mm focal length 1.25" ocular. I'd rather not be too dogmatic (as no actual 'harm' will be done): but DO NOT DO IT! For, an eyepiece of this focal length produces an exit pupil of 9.9 mm: way too big, causing a light loss and vague optical aberrations.
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