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    FAQ or Answers to Frequently Asked Questions                  Section 18
    This is a file containing answers, tips, hints and guidelines associated 
    with recurring  questions asked by photographers.   If you would like to 
    add a tidbit of knowledge to  this list just send it to   ANDPPH@rit.edu 
    who will gladly add it to this collection. 
                      These files are available in SECTIONS. 
              This is Section 18 and its contents are listed below.
    18.01  -< Depth of Field Calculation >- 
    18.02  -< How to Dispose of Darkroom Chemicals Safely >-
    18.03  -< Depth of Field in C >-
    18.04  -< Basic Stereo and Parallax Concepts >- 
    18.05  -< More Advanced Stereo Concepts and Stereo FTP site >-
    18.06  -< Photometry and Light Meters Primer >-
    18.07  -< More on Polaroid Transfer Process >- 
    18.08  -< Tailflash Synchronizer Circuits >- 
    18.09  -< Some aerial photography Tips >-
    18.10  -< Where to get film for SUBMINIATURE cameras >-
Note 18.01          -< Depth of Field Calculation >- 
                             DEPTH OF FIELD
Depth of field is to some extent an arbitrary matter depending upon
what one deems to be "proper" focus. Given this, you can calculate
depth of field, more-or-less.
Near limit of focus  =   F[squared]S
                       F[squared] + SAC
Far limit of focus   =   F[squared]S
                       F[squared] - SAC
Depth of field       = (far limit) - (near limit)
C = diameter of "circle of confusion" in meters (e.g., .000033m)
A = lens aperature or f-stop
S = distance to subject in meters
F = lens focal length in meters
The depth-of-field result will be in meters.
Note 18.02     -< How to Dispose of Darkroom Chemicals Safely >-
The following is a chart from the article "Pollution Solution",
"prepared by Peter Kolonia and Peter Krause, with technical information
contributed by Krause".  It  was in Modern Photograph, but the pages it
was on that I photocopied do not have the date on them.
Disposing Of Common Darkroom Chemicals
Chemical                           Disposal Method
All film and paper developers      Mix developer with acid stop bath, acid    
                                   fixing agent, or vinegar until relatively
                                   neutral pH is reached and gradually pour in
                                   drain with wash water.  Use pH indicating 
                                   paper to determine level of acidity.*
Stop Bath                          Mix with developer or borax until relatively 
                                   neutral pH is reached and gradually pour 
                                   into drain with wash water.
Acid fixer (with or without        Mix with developer or borax until relatively 
hardener), bleaches, and           neutral pH is reached and gradually pour in 
bleach fixes.  (Some fixers        drain with wash water; or arrange with a
are alkaline and essentially       commercial lab to accept exhausted fixer; 
neutral.  Check with pH paper).    or purchase a silver recovery unit.
Hypo clearing agent                Pour into drain with wash water.
Sulfur-type toners                 Pour into drain with wash water.
(brown, sepia, Polytoner)          
Selenium, gold,                    Heavy metallic content.  Use sulfur-type
iron (blue) toners                 toners, if possible.  Pour into drain with 
                                   wash water.
Wetting agent                      Dilute slightly with exhausted stop bath or 
                                   fixer and pour into drain with wash water.
Stabilizing bath                   Gradually pour into drain with wash water.
Sulfamic acid tray cleaners        Mix with developer or borax until relatively 
                                   neutral pH is reached and gradually pour 
                                   into drain with wash water.
* Available through Edmund Scientific, 101 E. Gloucester Pike,
Barrington, NJ 08007-1380
Note 18.03                -< Depth of Field in C >-
    The following two files (one called DOF.H, the other called DOF.C) will
    calculate the depth of field with various f-stops, focal lengths, and
    distances to subjects.  Built in help.  Here's how it works:
        1  Extract the first file as DOF.H
        2  Extract the second as DOF.C
        3  $ cc dof/c_opt/opt (on the VAXs, at least)
        4  $ dof == "$user:[abc1324.subdir]dof.exe"
           (this is the path to your DOF.EXE file, must be
           defined in this fashion, note the $ in the quotes)
        5  DOF
           (help is given)
#ifndef __DOF__
#define __DOF__ 1
#define C 0.000030      /* Fudge factor */
double doffront (
        double f,
        double s,
        double l)
  double  x, y;
  x = C * f * s * (s - l);
  y = (l * l) + C * f * (s - l);
  return (x / y);
double dofrear (
        double f,
        double s,
        double l)
  double  x, y;
  x = C * f * s * (s - l);
  y = (l * l) - C * f * (s - l);
  if (y <= 0)
    return (0);
    return (x / y);
#include "dof.h"
int main (int argc, char *argv[])
  double f;                     /* F number of lens */
  double s;                     /* Distance to center of shot, m */
  double l;                     /* Focal length of lens, mm */
  double x, y;                  /* Internal use in this procedure */
  int z;                        /* Internal counter */
  if (argc < 4)
    printf ("Usage:\n");
    printf ("\t%s f d l[...]\n", argv[0]);
    printf ("\nWhere\n\tf = f-number (ie, 2.8, 4, 8, etc)\n");
    printf ("\td = distance to subject in meters\n");
    printf ("\tl = focal length of lens in millimeters (ie 28, 50, 200)\n");
    printf ("\tOptionally, a series of lengths may be given\n");
    return (1);
  f = atof (argv[1]);
  s = atof (argv[2]);
  for (z = 3; z < argc; z++)
    l = atof (argv[z]);
    l = l / 1000;
    x = doffront (f, s, l);
    y = dofrear (f, s, l);
    printf ("\nUsing an f-stop of %g and a %2.3fm lens, ", f, l);
    printf ("a subject at %g meters:\n", s);
    printf ("\tD.O.F. front: %g m\n", s - x);
    if (y == 0)
      printf ("\tD.O.F. rear:  infinity\n");
      printf ("\tD.O.F. total: infinity\n");
      printf ("\tD.O.F. rear:  %g m\n", s + y);
      printf ("\tD.O.F. total: %g m\n", x + y);
  return (1);
Note 18.04          -< Basic Stereo and Parallax Concepts >- 
                              John Berkovitz
The subject is parallax or more specifically what we mean by same
in stereography.  Below are crude ASCII graphics which depict the
           L                                       x
           R                                  A    B
L is the left eyeball
R is the right eyeball
A is a vertical rod at some distance
B is a taller but otherwise identical vertical rod a little further away
x is a dummy point so I can use small angle approximations later
This is a plan or top view; we are looking down on the top of the
viewer's head and at the upper ends of the rods.  It may help if you
draw lines between each pair of real points and also a line between
x and L as well as x and B.
Distances are designated by their starting and ending points.
For example, LR is the interpupillary distance, usually around 65 mm.
Angles are designated by three letters, the vertex in the middle.
For example, the angles LRA and LRB are both 90 degrees.
>From the point of view of R, objects A and B have a common left edge. 
>From the point of view of L they do not if L can detect angle ALB.  
The detection of angle ALB is the crux of the matter, the heart of 
the stereo effect.
This is probably a good place to mention that there isn't only one
kind of acuity associated with the human visual system.  Normally when
we speak of acuity we are speaking of the ability to, say, separate
closely-spaced fine black lines on a white background.  In this sense 
of acuity, the best eyes can resolve about half a minute of arc and not- 
so-good eyes, two minutes of arc.  Usually one assumes the figure is one
minute of arc.  In stereo or vernier acuity (vernier acuity is the
acuity associated with lining up split lines such as on a vernier scale)
the figure is much smaller.  Stereo or vernier acuity is assumed to
be around six seconds of arc though there is at least one recorded 
instance of a person having three-second stereo acuity.
You can see from the diagram that if the distance RA becomes greater,
the distance AB must become much greater for the angle ALB to remain
detectable.  Assuming angle ALB is 6 seconds of arc, what is the
relationship of AB to RA?
First, we convert 6 seconds of arc to radians and find that it is
2.9E-5 radians.  So ALB = 2.9E-5.
ALB = ALx - BLx
but ALx = RAL and BLx = RBL
so ALB = RAL - RBL and we don't need the point, x, anymore.
RAL = arctan LR/RA
RBL = arctan LR/(RA+AB)
IF RAL and RBL are small angles measured in radians, we can say,
RAL = LR/RA   and   RBL = LR/(RA+AB)
So: ALB = 2.9E-5 = LR/RA - LR/(RA+AB)
2.9E-5 = [LR(RA+AB) - LR*RA] / [RA(RA+AB)]
Since AB<<Therefore:
>AB = 2.9E-5 [(RA)^2]/LR
If the approximation above regarding RAL and RBL is not made then:
ALB = 2.9E-5 = (arctan LR/RA) - (arctan LR/(RA+AB))
Solving this we get, step by step:
tan(2.9E-5) = (LR/RA) - LR/(RA+AB)
LR/RA - tan(2.9E-5) =  LR/(RA+AB)
AB =     --------------------  - RA            (Where LR = 0.065m normally)
         LR/RA  - tan(2.9E-5)
In this relationship, AB goes to infinity when the bottom line goes to zero.
ie: AB is infinte when 
    LR/RA - tan(2.9E-5) = 0
Solving this for RA we get
    RA = LR / tan(2.9E-5)
       = 0.065 / tan(2.9E-5)
    RA = 2236 meters
In other words, normal vision should be able to perceive the parallax
between an object A at range 2236m, and object B at a distance of
"infinity". I think that this is a little more than the figures I have
heard previously. It does of course depend on what you assume for the value
of stereo acuity (6 seconds of arc used above)
The only reason for working this through without the assumptions was that
John Bercovitz's posting got me thinking about all this.
Now I'll just put that final equation for AB into my spreadsheet and plot
me a handing graph to show the neighbours.....
Steve Spicer
Melbourne, Australia
(I hope my algebra is OK, I just don't have time to double check this
before posting!)
Note 18.05   -< More Advanced Stereo Concepts and Stereo FTP site >-
                         MORE ON STEREO PARALLAX
           also, at end, instructions on FTP info on stereo stuff
                            by John Berkovitz
I also wanted to talk a little about the effects of not maintaining
ortho conditions in stereo photography.  I think an intuitive way into 
this may be to first discuss the effects of binoculars on stereo perception.
The usual binoculars (the models which use Porro prisms as erectors)
do two things: they magnify and they increase the separation of the
Going back to our sketch:
           R                                  A              B
L is the left eyeball
R is the right eyeball
A is a vertical rod at some distance
B is a taller but otherwise identical vertical rod a little further away
>From this sketch I previously derived:
AB = 2.9E-5 [(RA)^2]/LR
AB is the smallest separation which can be detected at range RA.
2.9E-5 is the tangent of 6" of arc which is a figure for stereo acuity
The first thing binoculars do is to magnify the angle ALB.   This makes
the eyes sensitive to a smaller angle.  So the new angle which can be
detected is ALB/M where M is the magnification of the binoculars.
The second thing binoculars do is to increase the distance LR.  For small
angles, doubling LR doubles ALB.
So let's say that LR is doubled and M = 7.  How far away can you now
see what separation?  I suppose we need a new variable, S, which will
be the separation of the binoculars' objectives divided by the separation
of the eyes (65 mm).  In the present case, then, S = 2.  Taking these
effects into account, our modified formula becomes:
AB = 2.9E-5 [(RA)^2]/(LR*M*S)
So we can see a separation which is 1/M*S or 1/14th of the separation 
which we can perceive with our unaided eyes.  If we could in practice
separate something which was at 350 meters from the infinite background,
with the aid of binoculars we can now separate something which is at a 
distance of 14*350 = 4900 meters.
The next questions are "What is the effect of the increased separation
of the points of view when using binoculars?" and "What is the effect of
increased angular magnification when using binoculars?".
The increased separation of the points of view may be thought of as giving 
a giant's view of the world.  A giant would see the world same as you or I
but everything would appear smaller relative to his size.  That's why when 
you take pictures of scenes with widely-spaced cameras, you get a Lilliputian
version of the scene.  I realize that wasn't terribly rigorous.  8-)
I've drawn a sketch of how the geometry causes this.  It's in the photo-3d
ftp directory as "ortho.sep.ps.Z".  You can see from the sketch that
increased camera spacing gives an exact reduced model of the scene.  The model
is reduced in depth, width, and height.  So the reduced-size objects appear
nearer.  This means that height & width of a reduced object subtend the same
angles at the viewer's eyes as the full-sized object would.
The other problem is that of magnification.  Magnification causes an
apparent decrease in the depth of objects in the scene and also of
course a decrease in the distance from object to object along the line
of sight.  (Non-sequitur: Is this what would happen if you were looking
along the line of motion if you were approaching the speed of light?)
Sorry.  8-)  There is a companion sketch in the ftp directory called
"ortho.magn.ps.Z" which demonstrates the problem.  Usually in stereo 
photography we have the opposite problem, demagnification, when we
are viewing.  This is because it is easier to find a camera lens which
puts a wide coverage on the negative than it is to find a viewing lens
which will cover that angle.  The upshot is that most stereo cameras'
taking lenses are 35 mm focal length while most viewing lenses are 50 mm
focal length for a demagnification of 35/50 = 0.7.  The effect here is
to stretch the object along the line of sight from the viewer to the
reconstructed object.  The apparent size of the object in height and 
width does not change but the apparent distance to it changes.  The actual 
angles subtended at the eye by the object's height and width do change,
of course; that is the essence of magnification.  The apparent depth 
increases by the factor 10/7.
If you care to look at the sketches, you get to the photo-3d ftp
directory as follows:
% ftp csg.lbl.gov
account : anonymous
.., send ident as password... 

cd pub/listserv/photo-3d



get   will transfer file to your home directory..
At the present time the 3d directory looks like so:
           1545  Jun  2  1.index
          45512  Mar 29  3d-faq.ps.Z
          54068  Apr 12  3d.prod.serv
          21237  Apr 12  3d.prod.serv.Z
         203292  Mar 11  ES.CTD.ACHR.PS.Z
           2324  Mar  5  PStc.expl
          19890  Mar  5  PStc1.25.Z
         501655  Mar 18  archive_1.Z
         201485  Mar 25  dpthfld.ps.Z
         182768  May  4  ortho.magn.ps.Z
         184272  Jun 17  ortho.sep.ps.Z
          12041  Mar  9  photometry
         423407  Mar 17  raytrace.ps.Z
           6040  Mar  9  wratten.filters
"1.index" gives a description of the other files, as you might suspect.
John Bercovitz     (JHBercovitz@lbl.gov)
Note 18.06         -< Photometry and Light Meters Primer >-
                       The Photometric System in General
   followed at end with specific photographic references re: light meters
                          by John Bercovitz

        Light flux, for the purposes of illumination engineering, is
measured in lumens.  A lumen of light, no matter what its wavelength
(color), appears equally bright to the human eye.  The human eye has a
stronger response to some wavelengths of light than to other
wavelengths.  The strongest response for the light-adapted eye (when
scene luminance >= .001 Lambert) comes at a wavelength of 555 nm.  A
light-adapted eye is said to be operating in the photopic region.  A
dark-adapted eye is operating in the scotopic region (scene luminance
                Questions and Answers: Polaroid Transfer Process
What is a polaroid transfer process ?
        This is a process that transfers a polaroid image from the polaroid
film sheet to art paper. The procedure is to take a polaroid picture, start the
processing, peel the backing paper after about 10 seconds, place the developing
image onto damp art paper, rub / roll the image for 1.5 to 2 minutes and slowly
peel the film. What is left on the paper is a color dye image.
What kind of film can I use ?
        It's the color dye that makes the transfer work. B&W doesn't transfer.
        Use the "9" films such as 59, 669, ...   for making transfers.
        For 3x4, it's type 668/669 or the new Polacolor 100.  Polacolor 100
        has more vivid colors than the other two.  For 4x5, it's type 58/59 
        sheet film, or 558/559 4x5 pack film.
        The 64T also works, but it's a Tungsten film.  For 8x10, the film to
        use is type 809.  It costs about $10 a sheet.
        Integral (600) films do not transfer.
How long do I process before peeling the backing paper ?
        Time ranges from 5 seconds to 30 seconds.
        Polaroid seggests 10 seconds. The best time will
        be the result of your experimentation !
        Some say the longer you wait before peeling the film apart,
        the more likely the emulsion will lift off.  Of course, lift off
        could also be a desired effect.
        Choosing the time to pull apart the packet is quite
        critical, after 10 seconds most of the red is transferred to the backing
        If the film develops longer than 10 seconds, colors in the transfer will
        be less saturated. Not necessarily bad. Some have gotten good images 
        after a deliberate wait of 30 sec.
What kind of paper should I use and what do I do ?
        Hot pressed watercolor paper is probably the best bet for a 
        transfer surface. Warm temperature is claimed to be a 
        help. Some people soak the paper in hot water. You could use a hot
        lamp over your work surface to keep the surface warm.
        Light tones are easiest to transfer. Hot press gives you a
        sharper higher quality image, naturally it's more expensive.
        Some use wet rice paper with good luck.
        Then you need just the right amount of moisture.
        Make sure your paper is not too wet.
How about filters and color bias ?
        Many people use filtration to correct the imbalance;
        Polaroid suggests this in their literature.
        You can't expect perfect colors, or even close to perfect.
        It just doesn't work that way.
        The process has a built-in cyan color bias. Polaroid recommends
        a CC20R filter (I think) If you use a strobe flash, any kind of
        warm filter over the flash will help. If you are in a hurry and 
        don't have filters, use incandescent lights (yeah, 60-100 watt 
        household lights) This doesn't give true color, but if you want true 
        color you shouldn't use the transfer technique. If you use incandescent
        lights, beware that reciprocity failure sets in quickly with this
        type of film, compensate accordingly if your exposures are longer
        than 1/15 sec.
        Tip: Use a 30 magenta filter on your lens.
                   (it really helps the color)
        Magenta filtration will help the "whites" somewhat..
        Some people use a 20cc magenta or red filter to
        correct the blue cast.  You can also try to peel earlier.
How do I peel, place, roll and lift ?
        When making the transfer, press the film snugly against the transfer
        sheet. You will find that repeated pressing with the palm
        of you hand can work fine. Transfer for about 1 1/2 minutes before 
        peeling the film sheet away.
        1. Place neg on transfer paper quickly and carefully
                   (I use dry paper to transfer to, rather than wet,
                   it tends to be sharper)
        2. Use a rubber roller to bond the negative to the
                   transfer paper. (it takes about a minutes worth
                   of constant even pressure) You'll aquire the skills
        3. Let the transfer develop for about two minutes, then
                   pull the negative away VERY SLOWLY.
        Give a couple of rolls with a rubber roller (the type used for
        printing wood cuts) and then burnish with a wad of dry paper towel
        (you could use and soft ball of stuff).
        Peel apart very gently and slowly, and PRESTO! a transfer print.
        One trick I picked up from the Polaroid reps is to roll the roller 2-3 
        times, then turn the whole assembly over and rub the back of the paper
        with your hands in a circular motion.  The heat from your hands
        supposedly helps the transferring process.  
        Polaroid suggests that heavy pressure on dark areas is desireable,
        as it helps prevent the dark areas from peeling up. Polaroid even
        suggests rubbing those areas (with the back of a spoon?) to prevent 
        peel up.
It doesn't work, now what ?
        Don't be discouraged if you get part of the image lifted off in 
        the first few tries, or not much transfered at all.
        Experiment !
The colors aren't correct, what did I do wrong ?
        Probably nothing. Don't use this process if you want perfect colors.
Tips ?
        Have lots of paper towels and water to clean up with.
                   Transfers can be real messy!
Compiled by:  mcfarlan@eso.mc.xerox.com (Doug McFarland)
from messages sent by:  monson@hobo.ECE.ORST.EDU        (Ty Monson)
                        glp@fig.citib.com               (Greg Parkinson)
                        sinclair@nlbbs.rn.com           (Dan Sinclair)
                        bu890@cleveland.Freenet.Edu     (Brian Segal)
                        dsp@halcyon.com                 (Don Smith)
                        helen@seismo.gps.caltech.edu    (Helen X. Qian)
Note 18.08           -< Tailflash Synchronizer Circuits >- 
    Tailflash  synchronizers permit firing an electronic flash at the
    end rather than at the beginning of an exposure as is usually the 
    case. Their purpose is to  make a sharp picture due to electronic 
    flash exposure  next to a blurred one caused by a relatively long 
    tungsten  exposure.  Tailflash synchronizers make the blur appear 
    in the correct position with respect to the sharp image.
-9 volt ----------------------------------------------------.
                                              .__________.  |
        .--------------------------.     .____| 180 ohms |__*_____> to shutter 
        | 16 15 14 13 12 11 10  9  |     |    |__________|     
        |                          |     *------------------------> to flash 
        |        IC  4049          |     |    .-------------.
        |                          |     '----| Cathode     |
        |  1  2  3  4  5  6  7  8  |     .----|-------------|-----> to flash   
        '--|--|--|--|--|--|--|--|--'     '----| Anode       |
           |  |  |  |  |  |  |  |             |   C106D SCR |
           |  |  *--|--*--|--*--|-------------| Gate        |
           |  |     |     |     |             |_____________|
           |  |     |     |     |____________________________*____> to shutter
           |  |     |     |                   .__________.   |
+9 volt ___*__*_____*_____*___________________| 10 Kohms |___|
Note: On IC 4049 pins 9-16 are not connected to anything. Use a 16 pin IC 
      socket rather than soldering to IC leads directly.
Note: SCR output is polarized and if flash does not work one way try reversing 
      connections. SCR must be able to deal with 250 volts or so.
Note: * signifies connection
Note: When connecting flash to device it should fire. Wait a while and then 
      close the connection between the two shutter contacts. Nothing should 
      happen when you do this. When you disconnect them, however, flash should 
      fire. Shutter speeds shorter than 1/15 second may not work.
            .............         .............
+9 volt ----| 6.8 Kohm  |----*----| 6.8 Kohm  |-------------------> to shutter
            |___________|    |    |___________| 
                             |    ..............
                             |    |       Anode|------------------> to flash
                             |    |     Cathode|--------------*---> to flash
       ._____________________|    |C106D SCR   |              |
       |                          |        Gate|----.         |   
       |    .............         |____________|    |         |
       *----| 1N4148  | |----.             .________|         |
       |    |_________|_|    |  ........   |                  |
       |    .............    |  |      |   |  .............   |
       :____| 470 Kohm  |____*__| .1uF |___*__| 6.8 Kohm  |___*
            |___________|       |      |      |___________|   |        
                                |______|                      |
-9 volt ------------------------------------------------------*----> to shutter
Note: SCR output is polarized and if flash does not work one way try reversing 
      connections. SCR must be able to deal with 250 volts or so.
Note: * signifies connection
Note: Shutter speeds shorter than 1/15 second may not work.
Note: Connect to flash with female PC cord, to camera with male PC cord.
copyright 1993 - andrew davidhazy
  non-commercial uses permitted
Note 18.09             -< Some aerial photography Tips >-
                            AERIAL PHOTOGRAPHY TIPS
    Here are some tips from a photographer who posted them on rec.photo...
1.  Use a high-winged plane.
2.  Make sure the window on your side of the plane opens, some will, 
        some won't.  The glass adds too much distortion.
3.  Keep the horizon horizontal. Even if the horizon isn't in the 
        picture, by keeping it level the picture will make sense.
        (note: vertical is ok, too... I'm just saying the pictures where 
        I held the camera at weird angles made me dizzy)
4.  Shoot in the morning or evening. The additional shodows add depth to 
        the picture. 
5.  Keep the camera out of the airflow, and ton't touch the aircraft
        with your upper body.  It'll help you hold the camera steadier.
6.  Carry lots of film... it's expensive to drop into your local 
        grocery store to buy more. (pocket may be better than camera bag.
7.  Discuss communications with your pilot. What works for us is for me 
        to explain what I want to take a picture of and from what 
        side. He then fly's by and I get a picture (only one is really 
        good since only at an instant am I exactly perpendictular.)
        I usually then tell him to get farther from the subject, or 
        closer and do it again.  It is best for me to tell him what to 
        do. I tried asking him and get "I'm not the photographer".
        The person I fly with uses the trips to learn better aircraft 
        control.  He enjoys my directions and practices to maintain them 
        as exactly as possible.  
8.  Focus on infinity, and have the lens focused before the shot appears.
        You won't have time to focus and shoot when the decisive moment 
9.  I like the 100mm range for focal lentgh. A zoom was helpful. 35mm lenses
        tends to get landing gear. My shutter speed was 1/2000, (100asa) and
        there is some blur. I wouldn't want to enlarge much over 8x10. 
10. I find aerial shots not very creative, but extremely fun.  Although
        the pictures might not be "artsy", people tend to look at them 
        for a much longer time than they do for even the most expensive 
11. Watch for fog, it is no fun, and the pictures show it! We have 
        rescheduled many flights.  
12. Hail Mary's can be fun ( hold the camera out and point it straight 
        down and shoot)  --- try one, but don't drop the camera.
13. Try pictures of your workplace or school. everyone is always 
        interested in finding their car, of building
14. If you really enjoy it, you can make money with aerial photography.
        I've heard of several schemes, but havn't tried any yet.
15. If you want sharper pictures try renting a gyro-stabilizer. i've 
        never done it, but have had recommendations to the effect.
16. Have fun!
Lee McFearin.                                   #include 
Note 18.10     -< Where to get film for SUBMINIATURE cameras >-
    If you happen to need film for tiny cameras (such as the Minolta 16) that 
    use 16mm or Minox 9mm film here are two suppliers that may be of interest 
    to you.
1)  MicroTec Industries
    P.O. Box 9424
    San Diego,CA  92109
    (619) 272-8820
They do processing of color and B&W Minolta 16 and minox films.  Also they have
Minolta 16 bulk  rolls (100ft) for $50.  Their 18exp B&W is $5, color $6.
They also have lots of minox accesories, have then send you a catalog.
2)  Minolta Processing Station
    P.O. Box 2919
    Torrance CA.  90510
 They do processing of Minolta films and sell them. B&W 100 ASA for $3.50
 with discounts on larger quanties.
 The nice thing aobut the film canisters is that you don't have to destroy them
 to  get the film out. They just pop open. Once you have several on hand you 
 could get a bulk roll and probably be set for life as far as film goes.

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