PDA

View Full Version : DMK41 : focus plane distance adjustable within camera?



Thomas Ashcraft
February 16, 2010, 19:30:57
Can the focus plane distance be adjusted within a
DMK 41 camera?

I am imaging the Sun with a Lunt solar telescope and the full disk of
the Sun doesn't quite fit in the frame and is clipped at the poles in my
images. I am hoping to be able to move the focus plane inward a little so the
full Sun can fit on the chip. Is this possible?

Any information appreciated.

Thomas

Stefan Geissler
February 17, 2010, 08:30:47
Thomas,

no, the distance between sensor and the lens thread on the camera housing is fixed and should not be changed.

dsmith
March 18, 2010, 01:36:52
Actually, moving the chip in further would have no effect on the vignetting you are seeing. If the chip were further forward, you would obviously have to move the focusser further back to acheive focus. What you need is to reduce the focal length of the telescope by using a focal reducer (focal compressor). These are readily purchased and you can screw it into the front of the 1.25inch nosepiece.