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Thread: Switching back to condensor head, 45MCRX, from cold light

  1. #21

    Join Date
    May 2015
    Location
    SooooCal/LA USA
    Posts
    1,080

    Re: Switching back to condensor head, 45MCRX, from cold light

    One big plus using even white LED would be that most of the wattage is wasted heating up and using the IR and red end of the spectrum, just to obtain the green/blue wavelengths, so the full spectrum output of the LED will provide a much brighter source up there with much less wattage/heat...

    You did the right thing blacking out the inside lamp housing as the condenser just wants to see the even bulb surface at exactly the right height to focus to the condenser, but bright outer light can focus differently and cause outer ring, "kidney bean" effects, etc in the illumination field...

    Underexpose a piece of photo paper from a set up/focused enlarger without a neg to see how even it is...

    Steve K

  2. #22

    Join Date
    Jul 2016
    Posts
    1,440

    Re: Switching back to condensor head, 45MCRX, from cold light

    Quote Originally Posted by Paul Ron View Post
    woooooooooo that looks great!

    what diy does that need? i have no problem with diy but id like to see more details. have any links for all the details and availability of parts n controllers etc??

    did you build one?
    I'll send you a PM with some ebay links of suggested led control gear

    Regards

  3. #23

    Join Date
    Aug 2004
    Posts
    44

    Re: Switching back to condensor head, 45MCRX, from cold light

    the kidney bean effect reduced as soon as i used the flat black in the light head. i also painted the condenser chamber n that further reduced that kidney bean effect.

    ive been using my light meter to see how even my image circle is along the edges compared to the hot center.

    taking my compulsiveness to the nth degree... i blackened the bulb base and the condenser edges. everything is slowly getting better.

    the rgb led sounds like my next step though.... thanks Pere.

    EDIT: an observation... Im noticing some differences between condenser and diffusion that Ive grown fond of over the years...

    the condensers are a PITA focusing to stay in that even light without clipping the corners, where diffusion never needed any focusing and was even across the board.

    Also the choice of lens makes a huge difference with condensers. Im finding I have to match the lens to the format, its much more critical now.
    Last edited by Paul Ron; 22-Dec-2017 at 19:32.

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