Does anybody know the ID distance of the Lorex LNB8111B? I did a quick search but couldn't find any information. I'm not sure which Dahua camera this cross references to. I'm looking at starting to work on my camera layout and this information would be helpful.
I plan on setting up a camera and testing at 5' increments, but didn't want to reinvent the wheel if somebody already knows. Thanks.
Does anybody know the ID distance of the Lorex LNB8111B? I did a quick search but couldn't find any information. I'm not sure which Dahua camera this cross references to. I'm looking at starting to work on my camera layout and this information would be helpful.
I plan on setting up a camera and testing at 5' increments, but didn't want to reinvent the wheel if somebody already knows. Thanks.
The ID distance calculations is something I did to determine the point to which you will have 100 pixels per foot or more, and for that camera will be the same as the 4K / 8MP camera that was included in the Costco 4K Lorex kit.
The calculations are based on H FOV and H res, and represent the theoretical distance based on a perfectly effective pixel capture. Thus remember the range will drop at night, rain, fog,...
Thanks mat200. So short answer is 25'. That will definitely change how I will be planning on laying out the cameras. I'll check out all the info in the topics you linked as well. Thanks again.
Thanks mat200. So short answer is 25'. That will definitely change how I will be planning on laying out the cameras. I'll check out all the info in the topics you linked as well. Thanks again.
Cool! So for the sides of the house I could change the lenses as I don't need as wide a field of view since it's only a few feet between my house and fence line. That would definitely be better than investing in a camera every 25'. Still so much to learn...
You're not doing anything wrong, IPVM clearly uses a different way to determine the distance than I did. You don't need to worry about their calculations too much, just look at the way you can place the cameras.
If you like it seems that they're off about 25% for 90 degree FOV from what I calculated - so you can use 80 ppf to determine coverage.
The math I used is based on a slice of a circle and the pixel density at the circumference slice edge being 100 ppf - for a 1080p camera that section is 19.2 feet long.
( I've got a link in the SD post to the math referenced )
Thanks mat200. Is there a cheat sheet, calculator or equation on how to determine what kind of lens I need to narrow the FOV and to reach 100 ppf at a specific distance? I've been searching the forum and everything I'm finding is either people already know what they need or seem to be guessing. Am I missing something obvious?
Thanks mat200. Is there a cheat sheet, calculator or equation on how to determine what kind of lens I need to narrow the FOV and to reach 100 ppf at a specific distance? I've been searching the forum and everything I'm finding is either people already know what they need or seem to be guessing. Am I missing something obvious?
iirc there is some tools on IPVM Camera Calculator which are helpful - you may need to toggle some of the advanced settings for that.
Also, you can look at the Dahua spec sheets for other cameras with fixed lens and see the FOV specs to help guess what you need.
For the 4K camera - about 88 degrees you get an ID distance to 25 feet, at 44 degrees then it goes to 50 feet, at 22 degrees to 100 feet. ( of course you start to lose a good view of those close to the cameras eventually )
Just an update. I picked up a couple of 16mm lenses for a couple of the cameras. I swapped one out. Man that glue is tough on the original lens. Replacement screwed in without issue.
