Oberwerk BT-100-45

[Joves]

Anybody had any experience with one of these? Looks pretty sweet and 25x, 38x, 50x and 75x seem like pretty attractive magnification options.

[Laurie61]

I have a version of the BT-100-45's branded Strathspey here in the UK. I use them with a pair of TV 32mm Plossl and Neodymium filters.This gives 18.5 X a 5.3mm Exit pupil and 2.5dg field. I bought mine second hand, the collimation had stood up to three or four years of use without a problem although one side seamed slightly less sharp than the other. The good side will take a 6mm SPL and give 100X.

If I don't want to put out another scope I will use them with the 6mm in one side and the 32mm in the other which works quite well. In true binocular mode they provide nice immersive views and good contrast. I have also made a sun filter for these and they give great views of the Sun in white light.

[Joves]

Thanks Laurie.

I hadn't even thought of the benefit of having different eyepieces in each side, effectively giving you two scopes pointed at the same object at once. Great idea!

Do you find you use your Strathspey very often?

[Laurie61]

I have other scopes and like to give them all a run out It depends on what's about on which scope gets used. In the winter I will put the bino's out and use them whilst the other scope is getting cooled down. If chasing faint fuzzes they are useful for finding the target so I can aim the other scope. I've been using them quite a bit lately looking at the Sun. This is an afocal shot I took through them earlier in the year.