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max TFOV with focal reduction on the big easy

Started by rbelikov, 04/06/2006 10:41PM
Posted 04/06/2006 10:41PM Opening Post
The big easy manual ( ) on page 5 says that in the .66 focal reduction mode, on an 8" f/10 SCT, the TFOV can be as high as 1.3 degrees.

However, as far as I can tell, their focal reducer is a "1.25 optical nosepiece", meaning the field stop is a little less than 1.25, and the corresponding max TFOV is more like .8 degrees. Seems that using their focal reducer will just reduce magnification without increasing the FOV above .8 degrees.

So, how is it then that 1.3deg maxTFOV is possible in their setup? Have people actually observed 1.3deg FOV in the focal reduction mode on an 8" f/10 with the big easy?