thinkandbuild

I have a project coming up which requires unmanned DVR recording of an elephant exhibit which is rougly 100m by 200m. (300y by 600y). The requirement is to have no area of the enclosure unseen, using fixed cameras, for recording to show suffcient detail that the keepers can recognise each animal, that 24/7 recording take place, with no existing nightime illumination in place. I expect that I will need to conduct tests on a moonless night with a camera on a cherry picker and some IR lamps. The hurdles as I see it are: 1. How much illumination will be required, what type of lamp, power consumption, where to mount them etc. 2. Depth of field issues. If a single camera is mounted on the sleeping quarter's roof facing in one direction, will a single day/night camera, using B/W mode be able to provide the resolution required to see an animal in th e foreground and the background given that there may be 70m between the two. 2a. I have been told that the range of day/night cameras is limited. 1. Is this true? 2. If so, is it due to poor illumination, or is it inherent in such a camera? 3. I have read here about a variety of ifrared filters and cameras, with a range of frequencies. Is there a comprehensive discussion paper that details the various options of cameras, filters and lights for IR. I'm sure there are many other considerations that I haven't broached. If anyone has performed a similar installation and knows of traps that need to be avoided I would love to have your feedback. Thanks, Simon

Cooperman, thanks for the feedback. Yes, my conversion for our American friends was the wrong way around. We haven't used those 18th century standards since 1967, so we are a little rusty down here. The exhibit has a large barn which is planned to be used for mounting most cameras. There is an adjacent building that can look back at the barn. We may have to mount a single pole to cover one area that is in a blind spot from the buildings. I suppose I am assuming that any distance with suitable lighting is OK, eg up to 70m. If that were not the case, then additional cameras may be required on the perimeter, or as a last resort inside the enclosure. The reason for monitoring is for animal husbandry purposes. It will be going back to a local DVR. The DVR will then be connected to the main zoo network. If transmission is required, I can't see that being an issue. Were you asking about live feeds in relation to picture quality? The only crieteria set is that the animals must be sufficently detailed to allow the recognition of one from another to a trained eye. I am assuming that if that detail is present, there would be ample detail to see other activities such as birthing. It is a permanent enclosure with 5 elephants. There is no visible nighttime illumination, man made or god made. Are you suggesting that there is a level of background IR illumination that is going to help me here. I have done a science degree, but the natural level of background IR wasn't covered in my course! I appreciate your help. Simon