Make your own free website on Tripod.com

Underwater Photography

By Paul Janosi

Using the Nikonos Close-Up Outfit (Part 4)

 

Without a doubt close up underwater photography is one of the easiest underwater photographic techniques to perfect. Even beginner underwater photographers can get sharp well exposed, colorful pictures on their first dive.

Underwater Photography Part 1
Underwater Photography Part 2
Underwater Photography Part 3
Magnification
Picture Area
Depth of Field
Choice of Film
Manual Exposure
Advantages
Step by Step Instructions
Underwater Photography Part 5

Magnification
The construction of the close up lens is such that the same optics are used with either the 28 mm, 35 mm or 80 mm lens. Magnification and subject area covered is 1:6 ( 5 5/8" x 8 1/2" ) with 28 mm lens, 1:4.5 ( 4 1/4" x 6 7/16" ) with 35 mm lens and 1:2.2 ( 2 1/16" x 3 1/8" ) with 80mm lens.

Since the magnifications/subject size covered are different then those covered by the extension tubes used in macro photography the close up outfit should be considered as an addition rather then an alternate to extension tubes.

Picture Area
The area represented by the framer is 3/8" larger than the actual coverage of the lens in both vertical and horizontal directions.

Depth of Field
The depth of field is extremely shallow in close up photography. Make sure that the main point of interest in your close up picture is between the framer where it will be sharply focused. For example: if the creature has eyes, as long as the eyes are sharp the viewer will tolerate blur in the legs, tails or antenna.

With the close up lens when the 28 mm lens is preset to f22 the depth of field is about 3"; with the 35 mm lens it is about 2" and with the 80 mm lens it's about 1/2".

Choice of Film
The choice of film is dictated by the power of the strobe in use. With the Nikonos SB 102 a good film choice is ISO 50 or 64. With the less powerful Nikonos SB 103 strobe ISO 100 is recommended.

Front lighting is the best to use with the Nikonos close up kit. Side or top lighting will cause a shadow of the framer to fall on the subject.

With the SB 102 the built in the target light can be used to aim the strobe to the centre of the framer. After aiming is completed the target light should be turned off to conserve power.

Manual Exposure
The close up outfit can be used with all of the older models of Nikonos cameras, however it can only be used on TTL with the Nikonos V.

With the older cameras the shutter speed is preset to either 1/60 or 1/90 sec depending on the camera model used. The exposure is controlled based on the flash to subject distance. To determine manual exposure refer to detailed instructions discussed in "Underwater Macro Photography".

Advantages
One additional feature of the close up outfit is that it can be removed under water so the photographer can switch back and forth between close up and the lens in use.

Step by Step Instructions
The following list provides step by step instructions for taking close ups with the Nikonos V camera and Nikonos SB 102 or 103 speedlight:

  1. The camera and lens "O" rings should be cleaned and lubricated. Load camera with desired film and set the ISO dial.
  2. Preset shutter speed to "A" auto for TTL exposure control.
  3. Preset the focus to infinity.
  4. Preset aperture to f22. 
  5. Attach close up equipment. Begin by attaching the lens support rod to the viewfinder shoe of the camera body. Make certain lens is still preset to infinity. Loosen the knobs on the side of the close up lens mount. Lay the camera on its back and slip the close up lens down over the lens and support rod. Make sure it is mounted squarely. Tighten the knob on the side of the close up lens and the knob over the support rod. Do not overtighen. Attach the appropriate field framer to the framer support rod. ( Framers are marked 28 mm, 35 mm or 80 mm ) The identification on the frame faces towards the camera. Attach the framer support rod to the close up lens and tighten the mounting screw.
  6. Lubricate the "O" dngs and install fresh batteries in the speedlight. There are three "O" rings: one at the battery chamber cap and one at each end of the sync cord.
  7. Mount the speedlight bracket on the camera. Mount strobe arm reversed such that the top of the arm is over the top of the camera. Mount speedlight.
  8. In the water the space between the close up lens and the camera lens will flood with water, but it must be checked to see that there are no bubbles on the lens.
  9. Turn the strobe on and aim it such that the centre of the strobe hits the centre of the frame. The Nikonos SB 103 must be set to TTL. The Nikonos SB 102 has to be turned to the "ON" position with the power switch. The shooting mode selection must be set to TTL.