Guidelines for SetRise Tool®

All use of the SetRise Tool® is entirely the responsibility of the buyer and Victor Reijs will not accept any responsibility for any damage or injury done by the SetRise Tool®.

The SetRise Tool® is used in the following way:

  1. Preparing your SLR camera

  2. Turn your SLR camera up side down and remove the lens. You should now be able to see the downside of the prism, thought which one normally looks. This is most of the time a matte surface and one can sometimes see the scales for the exposure time or other things.

    Downside of prism in an Olympus OM10
  3. Creating a cutting template for the slides

  4. Cut the EMPTY slide in such a way that it fits above the prism. Usually you can cut away the green part, but start with fewer cuttings so that you can create a template for cutting the other slides.

    EMPTY slide on the prism
  5. Calibrating the focal length of the lens

  6. If you have a fixed focal length lens of 50 or 55 [mm], one can assume that it is calibrated accurately enough. So go to the next step.
    In case one has a zoom lens the following procedures can help calibrating the zoom lens at 50 [mm]:
  7. Explanation of the other slides

  8. Cut all the other slides in the same way as the EMPTY slide was cut. These slides (SUMMER..., EQUINOX, and WINTER...) have all comparable layouts: Azimuth
    The azimuth scale can be seen for RISE (normal way to put the slide on the prism) and SET (by turning the slide upside down on the prism).
    The green azimuth lines are at:
    Season RISE SET
    SUMMER... 50° 310°
    EQUINOX 95° 265°
    WINTER... 145° 215°
    The green azimuth line can be determined with the compass.
    Don't forget to compensate the compass reading with the difference between magnetic and true north:
      magnetic azimuth = green azimuth - difference magnetic and true north
                                                          (east is positive and west is negative)
      Green azimuth: [°]
      Difference magnetic and true north: [°](east is + and west is -)
      the magnetic azimuth: [°]
    Or when using information from a map:
      magnetic azimuth = green azimuth - difference magnetic and map north + difference true and map north
                                                          (east is positive and west is negative)
      Green azimuth: [°]
      Difference magnetic and map north: [°](east is + and west is -)
      Difference grid and true north: [°](east is + and west is -)
      the magnetic azimuth: [°]
    Apparent altitude
    The green apparent altitude line is the 0° apparent altitude reference line (the 0° has to be determined with a hand level).
    The latitude can be determined by map or GPS.
  9. Aligning the slides

  10. For the phenomena one wants to study, one takes the appropriate slide and puts it on the prism (like done with the EMPTY slide). After one has determined the green azimuth and green 0° apparent altitude line in the real world, one points the camera in such a way that the green lines of the slide are over the real green world directions. Now one can see in the camera where the first/last gleam of the sun/moon around 2250 BCE would have be seen: at the point where the actual latitude line crosses the real horizon.
  11. Storing the slides

  12. To keep your slides tidy (dust and so on are bad for the internals of the SLR camera!), put them in a plastic film containers (these are easy to carry and water proof).

Last content related changes: Sept. 2, 2000