Underwater Housings
Bolex Product Code:- HAMAR
The
HAMAR Bolex underwater housing allows you to don your scuba gear, breathing
apparatus and take your Bolex camera into uncharted territory under the
sea! It will accept any round base or flat base Bolex cameras except the
bayonet lens mount models such as the SBM, EBM or EL which had there own
separate housings designed, some of which even included provision for
using the 400ft magazine with take up motor.
However these bayonet housings are extremely rare and I have never seen one yet or there technical details so I will have to concentrate my discussions to the first and the most well known housing called the HAMAR underwater housing.
The Bolex Underwater Housing is designed for use with H8 cameras as well as with all the H16 C mount camera models. It is constructed so as to enable movie makers to shoot films underwater with utmost safety and ease. The Underwater Housing is absolutely watertight and can withstand water pressure to a depth of 300 feet.
The camera can be inserted or removed in a matter of seconds without any tools. The weight of the housing has been accurately calculated so as to ensure perfect stability for Underwater shooting, while giving the diver complete freedom of movement.
Fitting the camera in the housing
First
unscrew the cameras winding handle from the camera by turning it clockwise
till it comes off and then replace it by screwing in anticlockwise the
cog (M) in it's place. This will connect with a cog on the inside of the
underwater housing which will connect to the external winding handle so
you can wind the camera when it is under water. If you have a turret C
mount camera which has a turret handle attached remove it by unscrewing
the screw (D).
Second decide which lens you want to use on the camera. Only wide angle lenses are suitable for underwater filming on account of the short filming distances and the reduced depth of field due to refraction's in the water. You have a choice of 3 lenses if using a H16 camera for 16mm filming which are :- Switar f=10mm 1:1.6 or Switar f=10mm 1:1.6 RX, Switar f=16mm 1:1.8 or Switar f=16mm 1:1.8 RX, Yvar f=16mm 1:2.8. You have a choice of 4 lenses if using a H8 camera for 8mm filming which are:- Pizar 5.5mm 1:1.2, Switar f=12.5mm 1:1.5 fitted with Hyper Cinor, Yvar f=13mm 1:1.8 fitted with Kern Paillard Wide Angel and Switar f=5.5mm 1:1.6.
You
cannot use any other manufacturer's lenses on the account of the fact
that you would have to have a special collar manufactured.
The collars fit around the lens and have a cog which connects to a worm gear which enables the diaphragm of the lens to be altered under water.
Collars were only manufactured by Bolex to fit on the lenses listed above so you only have a choice of those to use with the underwater housing.
Third
you screw a metal bracket (P) into the bottom of the camera using screw
(N). If you have a roundbase camera you use it in the one screw thread
contained at the bottom of this camera or if you have a flat base camera
you screw it into the rear of the the three screw threads. Then you gently
screw the two screw threads labeled (Q) into the side of the camera which
have plastic heads which do not damage the metal on the side of the camera.
Now decide on the fps rate as this is something you cannot alter underwater, set the focus of the lens to one of two values either 6ft or 15ft based on the table below the lens you are using and how much light you think you will have available.
16mm Lens | Set lens f stop to | Set lens focus to | Apparent depth of field (feet) |
Switar f=10mm 1:1.6 and Switar f=10mm 1:1.6 RX | 1.6 | 6 | 3 - Infinity |
2.8 | 6 | 2.28 - Infinity | |
4 | 6 | 1.79 - Infinity | |
Switar f=16mm 1:1.8 and Switar f=16mm 1:1.8 RX | 1.8 | 6 | 4.29 - 11.08 |
1.8 | 15 | 7.28 - Infinity | |
2.8 | 6 | 3.67 - 20 | |
2.8 | 15 | 5.64 - Infinity | |
4 | 6 | 3.11 - Infinity | |
4 | 15 | 4.44 - Infinity | |
Yvar f=16mm 1:2.8 | 2.8 | 6 | 3.67 - 20 |
2.8 | 15 | 5.64 - Infinity | |
4 | 6 | 3.11 - Infinity | |
4 | 15 | 4.44 - Infinity | |
8mm Lens | Set lens f stop to | Set lens focus to | Apparent depth of field (feet) |
Switar f=5.5mm 1:1.6 for H8 RX | 1.6 | 3 | 1.60 - Infinity |
2 | 3 | 1.44 - Infinity | |
2.8 | 3 | 1.18 - Infinity | |
4 | 3 | 0.91 - Infinity | |
Switar f=5.5mm 1:1.8 | 1.8 | 3 | 1.45 - Infinity |
2.8 | 3 | 1 - Infinity | |
4 | 3 | 0.89 - Infinity | |
Pizar f=5.5mm 1:1.2 | 2 | - | 1.54 - Infinity |
2.8 | - | 1.23 - Infinity | |
4 | - | 1 - Infinity | |
Switar f=12.5mm 1:1.5 + Hyper Cinor | 1.5 | 6 | 2.43 - Infinity |
2.8 | 6 | 1.55 - Infinity | |
4 | 6 | 1.17 - Infinity | |
Switar f=12.5mm 1:1.5 + Hyper Kern Paillard | 1.8 | 6 | 2.43 - Infinity |
2.8 | 6 | 1.55 - Infinity | |
4 | 6 | 1.17 - Infinity | |
Yvar f=13mm 1:1.8 + Hyper Cinor 11 up to s/n 892.032 | 1.8 | 6 | 2 - Infinity |
2.8 | 6 | 1.55 - Infinity | |
4 | 6 | 1.17 - Infinity |
Now
place the camera on its base plate at the bottom of the underwater housing
and lock into place using lever (E)
Use of the Underwater Housing
There is little difference between filming underwater
than on dry land, except that the camera is operated by means of the controls
on the housing instead of on the camera itself. Remember, however, that
the lens is focused once and for all before diving to one of the distances
that are listed on the table
above, this can be done because depth of field is sufficient, even with
the wide lens openings The filming speed is also set before. The Diaphragm
can be adjusted, however, according to the amount of light available.