Lens option in CMA

What does the Lens option (DL.3) in the CMA actually do (I understand if you put in a long throw lens, you change the option) -- Here is why I'm asking.

I had some fixtures (I reset factory defaults on all of my units before uploading content) -- all shipping with standard lens sets. Apparently 2 of my units where set to LONG (and I didn't notice) -- but I couldn't get them to focus properly. After about an hour of screwing with it, I tried by chance changing the setting back to standard and that fixed the focus issue.

So why doesn't reset defaults, actually default the lens option. Also, isn't there a way for the fixture to "detect" the installed lens? and second, why does it affect the focus?
  • If you have set the wrong lens type, then the motor isn't being driven properly.

    Essentially the motors have to have different power settings via the driver chip to work properly in the different lenses. There is no way to "auto-detect" the lens as the only cables connected are the zoom and focus motors that HES puts on the Christie/Sanyo lenses.

    You should always run a "Calibrate Motors" from the fixture menu after you change this as well to be sure everyhting works properly.

    Not sure why "Factory Defaults" would not set the lens back to "Standard".

    Hope this helps. :)
  • All good to know. Maybe someone can checkout the issue in the software so others don't have my issues) haha
  • Hi Stephen,

    As Marty said, there's no way for us to detect which lens is attached to the projector. In fact, even in the stock set-up from Sanyo (without our zoom/focus motors attached) the projector itself has no way of knowing which lens is attached. It doesn't really care, as it's just sending light out of its aperture. We try to make things as simple as possible, so if the option was there to detect it automatically, we would take advantage of it.

    As far as the lens setting affecting focus: Each lens is a different size and the zoom/focus lens have different ranges (because of the different lens diameter and how they are constructed internally). So, we have to set a different speed/range on the motors for each lens to make sure the full amount of travel is used when adjusting the DMX value 0-255. Also, because of the way the motors mount on some of the lenses, some motors have to travel backwards. So, a focus value of 200 on the standard lens will cause the focus motor to move an entirely different amount than a value of 200 on the long throw.

    The fact that the lens selection doesn't change back to "Standard" when setting defaults is done on purpose. Everything that is changed when setting the Factory Defaults is a programmatic setting that doesn't have anything physical related to it. Because the Lens Option setting is related to a physically installed lens, we chose to leave it alone so that if an optional lens is installed, you can set the Factory Defaults and still have correct operation. There are arguments that can be made both ways as to what the correct functionality should be (and believe me, they were made at length by our development team), but ultimately we feel this is correct.

    Hope this helps. Please let me know if you have any other questions.

    Thanks,
  • All good. Now we know. I'll just remember to check it next time. Thanks for the explaination