Insomnia update

[erker@xxxxxxxxxxxxxx (Greg Erker)]

  Only had 2 hours of sleep last night: 10:30
til 12:30 when Beth wanted to be fed.  I was
still awake at 3 when she wanted to eat again.
Gravol and TV were ineffective. I gave up trying
to go to sleep at 4:30 and went down to my office
(as well as shorter visits earlier).

  BTW I have a 10 o'clock Dr's appointment to
hopefully get switched to some different meds.
So my 3D productivity is going to drop.

---
  Someone responding to my Diacord web page
had asked me about intermediate shutter
speeds (between the click stops).

  So I tried my Diacord L at 1s, 1/2s and
inbetween, timing with my stop watch. It
did appear to give 0.7 sec on the mid speed.
But when I tried the speed between 1/2 and
1/5 I got 1/5 all the time. So there may
be some intermediate speeds. I may check
someday when I have the camera and my shutter
speed measuring stuff at work. (Seikosah-MXL
shutter BTW).

  Next I tried the above with my 225. The
mid speed between 1 and 1/2 always came out
at 0.5. So I gave up. (Seikosha-SLV)

  (There was lots of measurement error
due to my slow reflexes so I did lots of
trials to see trends.)

---
  Worked on the projecting test slide with
camera body idea. I'll skip what didn't work
and cut to the chase.

  Taped my test slide flush with the back
edge of the body (about 5mm from film plane).
Focus camera body at infinity (because hopefully
all the cameras we get are in calibration there).
Shine my Maglight thru the test slide and in
towards lens. Get a circle of the test grid
visible (about 30 mm dia). Move the flashlight
around to illuminate the corners (while aiming
at the lens) and voila.

  A slight diffuser between the maglight and the
test slide may help. But I found it was impossible
to get a diffuse enough light to have the corners
properly illuminated when using a perpendicular
(non-moving) light.  I also tried a film strip
projector I have to try a semi-collimated beam.
Didn't work well.

  The maglight rules!

  My plan for this is to get some thick glass
cut to 2.5x2.5" and sandwich the test slide
in between. The glass will sit on the milled
filmplane rails and will hold the test slide
perfectly flat and at the correct distance
from the film plane to project an in-focus image
of the desired size on the wall. (Shutter
locked open on Bulb of course).

  My goal is to have the image big but still
close enough to be able to mark the wall with
one hand while aiming the maglight with the
other. If you have the image in focus then
the distance and angle the light comes from
doesn't affect the placement of the grid on the
wall (just the illumination level).

  So it seem perfectly possible to mark
dots on the wall to 1 part in 500 with this
low tech approach.

  When I'm done I send the test slide/glass
block and marked up paper and one of my
cameras to Bob. He goes through his batch
and we have them all ready to pick and choose
the closest matches.

  I didn't try to compare my Diacord to the
225 (just played with the 225). My office
is too cluttered to have that much wall
space. Perhaps I'll try tonight if my medication
change doesn't solve my problem.

---
  I noticed that the lenses aren't perfectly
flat field. If you focus with the center
then you have to move the focus lever about
2 to 4 mm to bring the edges into focus. For
the official testing we'll probably want to
focus using the edge dots since an edge to
edge measurement is more accurate than a center
to edge.

  I also noticed that if you stop down you
do bring both into apparent focus but the
dimming harms your ability to see the test
image (at least in my setup with poor
control of scattered light).

  The magnification changes very slightly
when you stop down. Less than 1% I'd say.
It's so subtle it almost looks like an
optical illusion (as the image gets dimmer).
Hopefully all Rikenon lenses will have this
effect and to similar degrees so that measuring
FL wide open is useful for the f stops we
really shoot at.

---

  Lastly I mounted some MF slides given to
me by Bill Bell. He's the guy I bought the
225 from and at one point I sent him some
of my MF slides to view (and a crappy cardboard
viewer). When he returned it he gave me
some slides take with his various Rollieflex's.
There were 6 shots, 2 were scenics, 3 were of
his daughter and 1 of a different little girl.

  Man what a people photographer! His scenics
were boring (IMHO) in 2D or imagined 3d but
his kid photos. Wow.  I'd like to take pictures
of Emily and Beth that were 1/2 that good.

  I mounted 2 separate 2D images in one
stereo mount. So you view them one eye at
a time.  I found it was no more annoying
than when I blacked out one eye. I still
felt the need to close that one.

  Boy is mounting 2D easy! Lay the slide
over the mount on the light box. Find the
cropping you like and tape it down. No
fooling with rotation and vertical alignment
between two images. Boy those flatties
have it easy :)

  And boy do Rolleis have big film gates.
One of the images was almost 60mm tall.
If I were shooting stereos with Rolleis
I'd be bugging Joel every day to make
a mount with bigger openings. Do you
know how big they are Eric?

  The 50x50 openings were just too much
cropping so I decided to use the back
52x52 opening. And the obvious occurred
to me to take an Xacto knife and enlarge
to 50x50 openings to 53 or 54 by the same.
No need to be straight or accurate. Works
like a charm. If I had had a sharp blade
it would have been a snap. So never again
will I struggle to align two 52x52mm backs.
(Add this to the Erker MF mount FAQ).

  It almost seems like a "well duh?" situation.
So obvious.

  One minor potential problem is if you
have a stereo slide with light coloured
areas in the cropped area then your uneven
cutting of the two back windows will cause
some retinal rivalry. But if you blacken
the front inside of the mount with felt
marker you'll be fine.

---

  That's all for now.  Even though I'm
here at work I'm off sick because there
is no way I can do any useful work with
my head this fogged. Dawn was working
nights last night (which was why I got
up for Beth) so she is at home sleeping
now. No point in me ruining her sleep.
If I fall asleep here at the keyboard
it's fine. Just don't want to miss my
doctors appointment.

Later - Greg sleep-deprived Erker