dopalgangr 1 Posted August 14, 2009 All, I have a couple of the Acti 1.3 MP cams and wanted to get a lens for them. They have 1/3" cmos sensors. My question is should I get a 1/2" lens or 1/3" since both will work. Which one will be the best? I'm looking at this one http://www.fujinon.com/ProductDocs/YV2.8x2.8SA-2.pdf or another that Fujinon makes. Anyone used these or have any recommendations? Thanks Share this post Link to post Share on other sites
thewireguys 3 Posted August 14, 2009 Yes a lens for a 1/2 sensor will work on a 1/3 sensor and you will have a better image. But a lens for a 1/3 sensor will not work on a 1/2 sensor. Share this post Link to post Share on other sites
Tailbone215 0 Posted August 14, 2009 All, I have a couple of the Acti 1.3 MP cams and wanted to get a lens for them. They have 1/3" cmos sensors. My question is should I get a 1/2" lens or 1/3" since both will work. Which one will be the best? I'm looking at this one http://www.fujinon.com/ProductDocs/YV2.8x2.8SA-2.pdf or another that Fujinon makes. Anyone used these or have any recommendations? Thanks If having a choice between a 1/2" and 1/3" lens I would go for the 1/2" because it leaves more options open to me should I want a 1/2" camera in the future. Plus, you get to use the "sweet spot" of the lens when mounted on a 1/3" cam. This means you generally won't be plagued with edge softness or vignette due to light falloff and barrel distortion. The only thing one should consider is the field of view of a 1/2" 3mm lens will have a slightly narrow FoV when mounted on 1/3". So it might have an equivalent FoV of 4 or 5mm. This probably won't be objectionable in most situations. It's like adding a slight bit of zoom. Share this post Link to post Share on other sites
thewireguys 3 Posted August 14, 2009 Great points "Tailbone" Share this post Link to post Share on other sites
Soundy 1 Posted August 14, 2009 Yes a lens for a 1/2 sensor will work on a 1/3 sensor and you will have a better image. But a lens for a 1/3 sensor will not work on a 1/2 sensor. Sure it will... it will just give a more distorted view. Share this post Link to post Share on other sites
dopalgangr 1 Posted August 14, 2009 Thanks for all the responses, this is what the Acti rep told me when I posed the same question to him??? You have to use a lens that is made for the sensor, so in this case you will want to use a 1/3†Share this post Link to post Share on other sites
thewireguys 3 Posted August 14, 2009 You can can use 1/2 lens you will not have a problem. If your camera is auto-iris then you need a 1/2 lens with auto-iris. If your camera is manual iris then you can us a 1/2 lens with a manual iris. Do not put a auto-iris lens on a manual iris camera you will only get a black image. Share this post Link to post Share on other sites
Soundy 1 Posted August 14, 2009 There is no legitimate reason you can't use a 1/2" lens on a 1/3" sensor. The mounts are the same, the optics work the same... the only reason you might choose a 1/3" lens is price (the 1/2" one would probably cost more for the same basic specs). By the same token, there's no reason you can't use a "regular" (non-"megapixel") lens on a megapixel camera. In each case, the higher-end lens will generally provide better quality or performance than its cheaper equivalent, but there's nothing that STOPS the cheaper lens from working. Share this post Link to post Share on other sites
Soundy 1 Posted August 14, 2009 You can can use 1/2 lens you will not have a problem. If your camera is auto-iris then you need a 1/2 lens with auto-iris. If your camera is manual iris then you can us a 1/2 lens with a manual iris. Do not put a auto-iris lens on a manual iris camera you will only get a black image. If your camera supports auto-iris, you can use an auto- OR manual-iris lens on it. The only limitation here is that an auto-iris lens won't work on a camera without the auto-iris driver. Share this post Link to post Share on other sites
thewireguys 3 Posted August 14, 2009 (edited) Yes a lens for a 1/2 sensor will work on a 1/3 sensor and you will have a better image. But a lens for a 1/3 sensor will not work on a 1/2 sensor. Sure it will... it will just give a more distorted view. I guess I should have gone into more detail on why you would not use a 1/3 lens on a 1/2 imager. Edited August 14, 2009 by Guest Share this post Link to post Share on other sites
Soundy 1 Posted August 14, 2009 Yes a lens for a 1/2 sensor will work on a 1/3 sensor and you will have a better image. But a lens for a 1/3 sensor will not work on a 1/2 sensor. Sure it will... it will just give a more distorted view. I guess i should have gone into more detail on why it would not use a 1/3 lens on a 1/2 imager. I've done it before, when testing an IQ701 when all I had handy was a 1/3" lens. Actually, at longer focal lengths, there was no noticeable difference. At wider views, though, the image became "rounded off", because the lens projects an area smaller than the sensor. Actually, I didn't get to test it, but I suspect adding a C/CS adapter to space the lens out a bit might at least partially compensate for this phenomenon... Share this post Link to post Share on other sites
thewireguys 3 Posted August 14, 2009 Yes a lens for a 1/2 sensor will work on a 1/3 sensor and you will have a better image. But a lens for a 1/3 sensor will not work on a 1/2 sensor. Sure it will... it will just give a more distorted view. I guess i should have gone into more detail on why it would not use a 1/3 lens on a 1/2 imager. I've done it before, when testing an IQ701 when all I had handy was a 1/3" lens. Actually, at longer focal lengths, there was no noticeable difference. At wider views, though, the image became "rounded off", because the lens projects an area smaller than the sensor. Actually, I didn't get to test it, but I suspect adding a C/CS adapter to space the lens out a bit might at least partially compensate for this phenomenon... Fine for testing but I would not sell it to a customer. Share this post Link to post Share on other sites
Soundy 1 Posted August 14, 2009 ^unless that's an appropriate view for the particular install. Share this post Link to post Share on other sites
dopalgangr 1 Posted August 14, 2009 Well, thanks again, I guess I will just get the 1/2. I figured it would work as the spec for the 1/2 on Fujinon's website say it will work on 1/2, 1/3, and 1/4. I just thought maybe these Acti's were special or something from what the rep stated. Share this post Link to post Share on other sites
thewireguys 3 Posted August 14, 2009 ^unless that's an appropriate view for the particular install. Find me a a megapixel camera manufacture that would recommend/support this and I will send you $1 . The whole idea behind megapixel cameras is better image quality so after spending extra money on a megapixel why would you save a couple of bucks on the lens which is the weakest link in a megapixel camera? Buy the best lens you can afford. Share this post Link to post Share on other sites
DoorMan 0 Posted August 15, 2009 The non-megapixel Fujinon lenses will only be non-megapixel toward the edges. At the center (and most of the distance from it) they will be at or better than 1.3 MP. This I was assured by Fujinon directly. I have confirmed this with the Fujinon p/n's YV2.1X2.8SR4A-SA2L 3 MP lens and YV2.7X2.9LRD4-SA2 non-MP. The second lens above is the one I use on the ACTi TCM-5311. At F.95 it is very bright and in very low lux who's looking for tatoo's anyways? With the 5311 I'm happy with either of the above. The second lens is less than half the price of the first. But the second lens is in no way shape or form half the performer of the first with a 1 MP camera. Share this post Link to post Share on other sites
Soundy 1 Posted August 15, 2009 ^unless that's an appropriate view for the particular install. Find me a a megapixel camera manufacture that would recommend/support this and I will send you $1 . The whole idea behind megapixel cameras is better image quality so after spending extra money on a megapixel why would you save a couple of bucks on the lens which is the weakest link in a megapixel camera? Buy the best lens you can afford. I was talking about using a 1/3" lens on a 1/2" camera... which at the shorter focal lengths will give a wider view, even if it is distorted. There may be instances where the extra FOV would be a plus despite the distortion. I do things all the time that manufacturers don't recommend or support... sometimes you need to come up with solutions that they simply haven't thought of. Share this post Link to post Share on other sites