Stereoh wrote:
I have a Denkmeier dieelectric coated binoviewer which I
haven't used for months. When I tried to use it yesterday
with 2 identical 15mm TV Plossl. I couldn't reach identical
focus. I have to pull one of the eyepiece a little to make
the view matched. For those who own Denkmeier. What do you
do when your bino got out of collimation??

What you describe is not a collimation problem but simply a slight
difference in construction, causing a slight difference in the focal
points of the two eyepieces...OR, it's the difference between your
eyes. Many (most?) of us have slightly different 'prescriptions' for
each eye.
This is precisely why Denkmeier (and some others) added a Diopter
adjustment to their newer model bino-viewers. So that each eye can be
focused independently.
In the earlier Denks (and in the TeleVue, etc.) binocular viewers, you
must focus the telescope with one eyepiece...then slide the OTHER
eyepiece in or out to match the focus of your other eye...locking that
eyepiece in place to hold the focus.