Coolpix 5400

The Coolpix 5400 can be used for digiscoping, but
unlike the earlier Coolpix swivel body cameras, it has
an external zoom lens that has to be considered, and it
requires eyepieces with a lot of eye relief to be able to
take pictures without a vignette.

My first attempt was to use my Swarovski 15x
eyepiece, which has an eye relief of about 31mm. It
was made primarily for viewing, so it has as fair
distance of metal cylinder that rises above the top
glass surface on which a longer rubber eyecup is
attached to make viewing comfortable. I removed the
eye cup and removed most of the metal cylinder to
give an effective eye relief of about 27mm. This is
enough to make it useable without vignette only at a
camera zoom setting of 12.7mm which yields about
920mm in 35mm equivelant at f/3.7.

What I have done is add some extension to reduce
the minumum focusing distance of the scope and I use
this eyepiece for photographing birds at close range.

By using the camera zoom at 12.7mm, the
camera zoom is really unuseable. If you
accidentally hit the telescope eyepiece with the
lens by zooming in, it stops immediately and you
get a "lens error" on the LCD. You have to
remove the battery to reboot the camera as a
"lens error" seems to lock up everything.

This eyepiece is very acceptable configured like
this as far as picture quality is concerned, but I
wanted an eye piece that would allow me to use
the camera zoom, not only for composition
purposes, but for zooming out a long distance to
locate the subject and then zoom back in.

I found this in the Televue 40mm Plössl eyepiece.
This requires an adapter to allow the spotting
scope to accept 1.25" eyepieces.