Author Topic: Let's talk LENSES!  (Read 3150 times)

BiduleOhm

  • Jr. Member
  • **
  • Posts: 71
    • View Profile
Re: Let's talk LENSES!
« Reply #30 on: October 14, 2018, 01:44:52 AM »
This kind of lense usually take a 9-12 V power and the composite video signal. In short they look at the average level of the video signal to know the luminance and open/close the iris. You can see in the photo of the datasheet it's the case here and you even have the color of the wires matched with what they do. So by sending a 0 to about 1 V DC voltage at the video input you should be able to control the lense iris.

I plan to test this when I get this lens (thanks for posting the link BTW ;)) and post a simple schematic if you want to do the same.

Nikon1

  • Full Member
  • ***
  • Posts: 138
    • View Profile
Re: Let's talk LENSES!
« Reply #31 on: October 14, 2018, 02:02:09 AM »
Oh, Wow, Thanks for the info. I never knew how those Auto-Iris Lenses Worked. I also never actually owned one myself. But good to know anyways.
.
I wont buy that lens, since it is for 2/3", which is perfect for the Chronos, but wont cover the 1" sensor of my Nikon1 completely without vignetting (Just guessing). Just stumbled across this thing on Ebay and found, that it would be worth posting here since the Lens is most likely good brand Quality and quite Cheap, very wide and a good Fit for the Chronos. Also, most people would have the 12-75mm Lens, so an 5,6mm like this would be an Nice addition to anyones Camera, both for wide-Angle/ Tight spaces and also for lower Resolution/ very high-framerate Shooting.
.
If someone buys this, and happens to own some Kind of mirrorless Camera, it would be very nice if he could take an image with this lens, if the image Circle of the Lens is 15mm or bigger, i will also get one of those. Otherwise its not worth it for the use on the Nikon1 for me.

BiduleOhm

  • Jr. Member
  • **
  • Posts: 71
    • View Profile
Re: Let's talk LENSES!
« Reply #32 on: October 14, 2018, 02:27:57 AM »
There's also the ones who don't have any electronics inside (they're called DC iris; the one you posted is called video iris) and the camera do all the job, they have a 4 pins square connector instead of the mini-DIN like connector; 2 for motor and 2 for feedback (and both are coils like in a galvanometer so be careful with what you power it).