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RE: [APML] Nikon DW-4 help
Emmanuele,
I also use the DW-4. The pipe on the DW-4 should be adjusted until it is
focused on the focusing screen. The adjustment is there to allow people
that normally wear glasses to adjust for their vision. Once the DW-4 is
adjusted for your eyes, all focusing should be done on your scope.
Good luck and clear skies,
David
Dear all,
just back from vacation, I've got a question to pose to the whole list
about correct focusing with the Nikon DW-4 magnifier.
Some weeks ago I tried to use it for prime focus photography with a Nikon
F3 (with red-dot, D-type focusing screen) and a 8" SCT: when framing, the
field seemed correctly in-focus, but when I got my slides developed stars
did have very cool donut-like shapes. So, here is how I proceeded.
Since one can focus both by turning the DW-4 pipe and through the scope's
focus knob, I thought the most correct way was to block the DW-4 and use
only the scope's knob. The DW-4 body has a vertical white line on its back,
and its turning part has a small white dot which, I suppose, should be
brought to perfect match in order for the focus on the film plane to be OK.
Here's what I noticed:
1) When the dot and the line were aligned by turning the magnifier's pipe
clockwise, then by no means could I get the stars in the magnifier to look
properly focused by turning the scope's focus knob.
2) When I turned the DW-4's pipe clockwise _all the way_ down, the star
field looked as crisp as I could ever want, but the actual shots did not.
What am I missing here? Could it be my fault (most likely) or perhaps a
flaw with the DW-4? Any suggestions/links will be highly valued.
Please note that the DW-4 (used) was bought some months ago in San
Francisco by a friend of mine, so I guess I can't do much about it if it
happens to be the DW-4. It is in overall good condition, except for
slightly twisted hooks, which make attaching it to the camera not so smooth
an operation: however, once mounted, it stays firmly in its place.
Thanks
Emmanuele Sordini
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