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Size is relative

Started by DonDurbin, 03/19/2005 06:46AM
Posted 03/19/2005 06:46AM Opening Post
To All,

Here is an image with interesting proportions. This is my Siebert 45mm Elites inside my clubs 16" SCT. This is an F17.5 with a focal length of 7000mm.

This scope has limited focus in-travel. The primary and secondary mirrors are fixed. This telescope uses a 16 inch diameter paraboloid mirror as its primary optic. At the time it was built, it was one of the largest amateur telescopes in the State of Ohio.

The Siebert Multimag made focusing in this telescope very easy. I have yet to fnd a telecope with a 2" focuser that I cannot use. I ended up with a 1.08X configuration similar to what would I have used in a refractor. It probably would also have focused going straight in without a corrector, but I thought the convenience of the diagonal was worth the minor magnification.

Using Siebert 36mm EPs we had a 210X view. That worked out nice for Saturn and the Moon. It was a little early for Jupiter. We also swung the scope over to M42 and got a very impressive view of the Trapezium.

I have also used my 22mm BlackNights on this scope with a Siebert 1.3X OCA. The view was nice, but not anything like this.

Using a telescope that has a 7000mm focal length, I have to say that having a 2" binoviewer that can use 36mm EPs without vignetting, is really the ultimate. I really like all my 1 1/4" binoviewers, but I love my 45mm 2": Elites.

Don Durbin

Burgess BV125 Model C
Original 22mm BlackNights with Diopters and focal reducer
45mm Elite BlackNights with Diopters
Sieberts 1.3X OCA, Sieberts UltraBarlow, Sieberts Multimag OCA.
Denk IIs
Denkmeier 2" SCT Star Diagonal (Modified)
Denkmeier 2" Star Sweeper SE
Denkmeier 1 1/4" Star Sweeper SE
Stellarvue AT1010
Meade ETX90
Stellarvue 102APO
Orion 100ED
Celestron C9.25
Orion Atlas 8"
Meade 152ED

Attached Image:

DonDurbin's attachment for post 22975