The AV110 was developed for the use of auto focus lenses in the U-A... series of ewa-marine housings. The function of the AV110 is to ensure a fixed and rigid connection of the housing's front port to the tripod thread under the camera's body. This then allows the autofocus to lengthen or shorten the effective length of the lens without beeing effected by the surrounding water. Without the AV110 the lenses motor would have to "pump" air from the rear of the housing to the front, and vice versa, during focussing. This definitely exceeds the design specification of the motor and could lead to damages of the lenses mechanics.
Naturally, the AV110 can also be used in all the current housings of the U-F... series.
There are three different versions of the AV110:
- AV110 as supplied in the U-A and U-AX (System length: camera /lens max. 170 mm).
- AV110-D as supplied in the D-A and D-AX. For cameras wher the tripod mount is not in line with the lens (as is the case with some smaller digital cameras).
- AV110-P For the use with cameras that have a large body (eg. the Canon EOS1 or Nikon F5) in the ewa-marine U-AXP housing (System length: camera /lens max. 170 mm).
- AV110-L For the use in conjunction with large zoom lenses (eg. 300 mm focal length) in the ewa-marine U-AZ housing (System length: camera /lens between 170 and 230 mm).
The AV110 was developed from the predecessor, the AV100. Housings that were designed for the AV100 can also use the AV110. Older housings, that were supplied with the AV90 can not use the AV110! (please note, spare parts for the AV90 are still on stock, if required)