Hi Yves
To my knowledge as Lee says the Diascope was updated from the green and silver 20x60 versions in 2013 to the black 20x75 single dual focuser. I have a 2015 85T*FL model which i have found excellent. The image at 20 through to 75 is natural and pin sharp. The FOV is also superb and because the eyepiece is big it feels very comfortable to use and has good eye relief. It is built like a battleship....well crafted and handles well . It is extremely smooth and fast to focus. I have the latest version stay on case....also very well made but the whole package needs a good tripod as its quite heavy.....about 5.5 lb with eyepiece, case and arca Swiss qr plate. I use a Benro CF tripod with S6 fluid head. You'll need a good fluid head to stabilise the scope. It's great for phonescoping also. I use a Samsung S9+....and mount it on a PhoneSkope case and eyepiece attachment with blue tooth shutter control.
You might guess from this that I'm a big fan of Zeiss.....
Here's a picture I took yesterday....I think the photos compete with some of the pro cameras and big lenses ( only my opinion).
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