the vignetting with digiscoping the sionyx to the telescope is a problem. The problem is the focal length of the sionyx is 47mm (distance from sionyx front lens to the chip). However, most telescopes only have eye relief up to around 20mm or maybe 30mm for big lo power lenses. so putting the sionyx up to these telescope eyepieces is like lookiing through the eyepeice with your own eye being 47mm distance from the eyepiece, this results in the eyepice image not filling your view, you need to put your eye closer than or equal to the quoted eye releif distance. The net effect is the sionyx cant get its eye close enough to the eyepiece within the eye relief range, resulitng in a circle vignetting ie its like looking through a circular hole in the middle of the sionix field of view. You could use zoom but because its digital you are losing resolution. The only solution is to get a big glass eyepiece say 2inch and also a lo power for eye relief. It might be better to use a rifle scope which has long eye relief. OR change the lens on the sionyx to get an effective reduction in focal length.
Otherwise if you digiscope the sionyz with astro eyepieces you will get vignetting, you lose half of the sionyx field of view it can only see through a circle in the middle. Which also measn you cant fill an image across the whole chip ie across the 720p pixels, so you are losing resolution. Its just about ok with a 30mm or 40mm eyepiece, anything smaller and you are looking through a small port hole.
Ok so if i use a 30 or 40mm eyepiece i pretty much fill the sionyx image, but because my scope is 410mm focal length i only get x 10 to x 15 mag, which should still produce some nice images in the sionyx.
experimentation continues
