Setting lenses in hotel rooms
Occasionally a larger installation would be required, one such was several one-inch nuvicon pan tilt and zoom, infrared cameras were to be installed at Pork Farms in Nottingham.
The cameras would be installed with a zoom lens, fitted inside an environmental housing which had a heater at the front to prevent the glass from fogging, a wash wipe unit similar to a cars wipers would be fitted and the housing bolted to a large block containing electric motors for movement, a pan and tilt head, under the housing there would be a plate to which was bolted two infrared projectors, these typically had five hundred watt lamps behind a glass infrared filter which looked like plot toffee. One would be long range, and the second would have a Fresnel lens fitted to make its beam wide angle.
When a zoom lens was installed on a camera, it was always necessary to set the camera’s tube position to suit the lens, the tube and coils sat in a rack which could be moved forward and back on a very fine screw thread, this changed the distance between the tube and the lens to achieve correct focus across the whole range of the zoom on the lens – CamEra engineers gave this a nickname, ‘racking the camera’.
It was essential to rack the cameras at night, as infrared light focuses at a slightly different distance from the lens than white light and with the iris fully open to say f1.2 focus became critical.
To save time, we decided to rack all the cameras in the hotel room that evening, that way we could simply fit them the next day and did not need to wait for dark so could leave for home. The cameras, complete with infrareds and pan and tilt heads were enormous.
We opened a fire door onto a fire escape to the car park and lugged the cameras to the room, powering them up and pointing them out of the window we could now set the lenses. However, we had not allowed for the heat of the infrared projectors, one of the cameras had a sticky rack and needed some time to adjust, during which we burned two black circles into the curtains either side of the camera. Nothing was said by the hotel, but they must have mused, just what were we doing to burn the curtains like that.
The following morning, one of the cleaners caught us lugging three gigantic cameras out of the fire door exit to the car park, we smiled nicely at her and she did not ask what we were doing.
The engineer I worked with to install the system insisted on stopping in the hotel of his choice, it was not immediately apparent why he would choose this one as it was miles away from the site, on the wrong side of town and a bit run down and scruffy. He also insisted we book two rooms, normally two engineers working away from home would share a twin.
The following morning, the grin on his face said it all. He came clean and admitted that he had stayed in the hotel twice before, that on the first occasion, he asked for a 7:00 alarm call and the attractive receptionist had woken him up with a sex act. The second time he stayed, she was not around, but he wanted to give it another go, and this time his patience and persistence had been rewarded.
We concluded that either security was very lapse in the hotel, or that the staff were so badly paid, they did not see such an incident as being any of their concern.
Enjoy my books
Purchase Kindle Edition £3.21
Download pdf file free