bgd Posted January 27, 2008 Share Posted January 27, 2008 Hi there, I have difficulties in sourcing lenses designed to match 1/2" chip. I have been looking on various online stores as well as the famous auction site and all I can find are 1/3" or 1/4" lenses, but not 1/2"? I require the lenses to fit Baxall High Res mono cameras model TCM258LV with 1/2" ccd. Is there any way of fitting 1/3" lens to camera with 1/2"ccd? If yes what will be the effect? I intend to use the cameras to cover front patio, back garden and shared drive all located around typical semi detached property. I originally purchased some high res colour cameras and was really dissapointed with the results, so opted for the mono cameras above as they have very low lux spec, but I never knew lenses would be hard to find. Any help on this would really be greatly appreciated. Link to comment Share on other sites More sharing options...
spider Posted January 27, 2008 Share Posted January 27, 2008 Hi, Any of the plethora of CCTV suppliers will easily source a 1/2" lens for you, if you use a smaller lens you will have a tunnel effect on the displayed image. Good luck Link to comment Share on other sites More sharing options...
bgd Posted January 27, 2008 Author Share Posted January 27, 2008 Hi,Any of the plethora of CCTV suppliers will easily source a 1/2" lens for you, if you use a smaller lens you will have a tunnel effect on the displayed image. Good luck Thanks Spider, can you recommend any suppliers (if allowed to post links in the forum)? All UK based sites I checked do 1/3" lenses...Doesn't 1/2" supposed to be a better lens and industry standard or perhaps old standard as it seems it's been overtaken by 1/3 and 1/4 chip / lenses nowadays? Link to comment Share on other sites More sharing options...
spider Posted January 28, 2008 Share Posted January 28, 2008 Norbain or ADI-Gardiner, it might be cheaper to replace the camera in the end! Link to comment Share on other sites More sharing options...
Guest anguscanplay Posted January 28, 2008 Share Posted January 28, 2008 Thanks Spider, can you recommend any suppliers (if allowed to post links in the forum)?All UK based sites I checked do 1/3" lenses...Doesn't 1/2" supposed to be a better lens and industry standard or perhaps old standard as it seems it's been overtaken by 1/3 and 1/4 chip / lenses nowadays? all to do with cost - see Link to comment Share on other sites More sharing options...
Doktor Jon Posted January 28, 2008 Share Posted January 28, 2008 bgd, You can use any 1/2", 2/3" or 1" format lenses on your camera, and most of the major lens manufacturers produce optics in these ranges. Just out of interest, what lenses were you looking for ... ? D.J. Link to comment Share on other sites More sharing options...
bgd Posted January 28, 2008 Author Share Posted January 28, 2008 Thanks guys, tried to check Gardiner, but their web site was down last night.Managed to locate a couple of Computar HG4514FCS 4.5mm 1/2" CS auto iris lenses, these should be fine for my requirements I hope (will use to cover drive & rear patio)? I know that one should not use smaller lense on larger ccd, but asked that question anyway just to see what's the response from the trade guys who might have been in a situation where they needed to compromise (ie when one had 1/3" lens in stock instead of 1/2" unitil next delivery or similar situation). Probably stupid questionm, but let's say I needed to use 1/2" 4.5mm lens, but only had 1/3" 3.5mm lens, would use of this lens make the view much narrower ie. by such large margin that's unusable or it could still be used albeit with somewhat limited field of view? Link to comment Share on other sites More sharing options...
Doktor Jon Posted January 28, 2008 Share Posted January 28, 2008 I know that one should not use smaller lense on larger ccd, but asked that question anyway just to see what's the response from the trade guys who might have been in a situation where they needed to compromise (ie when one had 1/3" lens in stock instead of 1/2" unitil next delivery or similar situation).Probably stupid questionm, but let's say I needed to use 1/2" 4.5mm lens, but only had 1/3" 3.5mm lens, would use of this lens make the view much narrower ie. by such large margin that's unusable or it could still be used albeit with somewhat limited field of view? A 3.5mm lens on a 1/2" format would probably take in about 97 degrees horizontal coverage, which is classed as an ultra wide. If you use any lens on a larger format imager, then the view becomes wider. Obviously if you use a given lens on a smaller imager (e.g. 1/2" optic on a 1/3" camera) then the opposite happens and you have less width of coverage (field of view). In practice, it's quite likely that if you use the 1/3" lens on your 1/2" camera, then some degree of "vignetting" would occur, so the corners of the image will probably be missing. The problem with using any lens is that the performance drops off as you get towards the edge of the image, so if you used a 1/3" on a 1/2" camera, although you may well get away with a usable picture (apart from the missing bits ), the actual optical performance would probably be poor on the extreme edges. Hope this makes sense Link to comment Share on other sites More sharing options...
bgd Posted January 28, 2008 Author Share Posted January 28, 2008 Doktor Jon, thanks for your quick reply. I also ordered one 1/3"lens, mainly for experimental purpose as it was fairly cheap so will have a play when it arrives... Link to comment Share on other sites More sharing options...
Doktor Jon Posted January 28, 2008 Share Posted January 28, 2008 Doktor Jon, thanks for your quick reply.I also ordered one 1/3"lens, mainly for experimental purpose as it was fairly cheap so will have a play when it arrives... If it's cheap, don't expect it to blow your socks off. Perhaps the biggest problem in the biz (and this includes cheap board based cameras), is manufacturers using crepe lenses on technically half decent cameras. Whatever resolution the camera is capable of producing, if you put a rubbish lens on it, then it will output rubbish pictures Sorry if that sounds a tad blunt, but I'm a bit grumpy tonight Link to comment Share on other sites More sharing options...
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