Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,907   Posts: 1,555,995   Online: 1105
      
Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 26
  1. #11

    Join Date
    Nov 2009
    Location
    Capital of Oregon Territory
    Shooter
    Multi Format
    Posts
    778
    For a spot probe you may probably want something more sensitive, I'm not sure. I guess, you could add a small lens in front of it which could improve low-light characteristics. The temperature is in C, so you'll be staying in -10+40 range most of the time which gives about 0.002 LUX error. Does not seem to be too bad. I was thinking about building light meter into a watch, so I could just calibrate it at 98F and temperature would become totally irrelevant ;-).

    If it's not too much trouble, please keep us updated about your investigation, because I might be following your footsteps soon.

  2. #12
    BetterSense's Avatar
    Join Date
    Aug 2008
    Location
    North Carolina
    Shooter
    35mm
    Posts
    2,876
    Then perhaps you should provide a link to the plans and circuit diagram!
    There is no real circuit diagram; all the information is in the TSL230 datasheet. Here's a picture of two of my older meters though.

    f/22 and be there.

  3. #13
    benjiboy's Avatar
    Join Date
    Apr 2005
    Location
    U.K.
    Shooter
    Multi Format
    Posts
    6,909
    I'm in awe at the depth of knowledge and expertise we have from our members, we really have some very talented people in our midst.
    Ben

  4. #14

    Join Date
    Nov 2009
    Location
    Capital of Oregon Territory
    Shooter
    Multi Format
    Posts
    778
    BetterSense,

    It's a cool device, I can see how it could be easily hooked up to a microcontroller - just count number of pulses in a time interval, and you're done. Cool. Also the light spectrum is very wide, so if you add an IR filter, it would make a dream meter for IR shooting.
    In your experience, how sensitive is it in low light? Is it usable for star-trails photography? How about measuring a candle-lit room?

    Eugene

  5. #15
    BetterSense's Avatar
    Join Date
    Aug 2008
    Location
    North Carolina
    Shooter
    35mm
    Posts
    2,876
    You can use it basically arbitrarily dark; it just takes that much longer to take a reading. You can design your software to measure pulse length too. Eventually dark-current will get you, but you can calibrate that out for the most part. My incident meter transitions from frequency-averaging to pulse-width-measuring regimes somewhere around EV0. I didn't bother adding this functionality to my spot meters because you would have to hold still for several seconds on target; at light levels that low, I don't find metering very useful for photographic purposes, with reciprocity failure and all.
    f/22 and be there.

  6. #16

    Join Date
    Aug 2009
    Location
    Selah, WA
    Shooter
    Multi Format
    Posts
    255

    MicroProcessors

    Even found a couple of links in the various comments above for a Basic stamp app, and an AVR example.

  7. #17
    Hexavalent's Avatar
    Join Date
    Nov 2009
    Location
    Ottawa, Ontario, Canada
    Shooter
    Multi Format
    Posts
    545
    Blog Entries
    3
    PICs, Basic Stamps!
    C'mon we're supposed to be Analog here - how about a couple 12au7's and a neon voltage reference
    - Ian

  8. #18
    holmburgers's Avatar
    Join Date
    Aug 2009
    Location
    Rochester NY (native KS)
    Shooter
    Multi Format
    Posts
    4,420
    Images
    2
    Please, somebody make an IR light meter.
    If you are the big tree, we are the small axe

  9. #19

    Join Date
    Aug 2009
    Location
    Selah, WA
    Shooter
    Multi Format
    Posts
    255
    Hollowstate lives!!! Good op amp designs were a tought go before IC's, 741 op amp's still considered Analog, right?

    So,,, Hexavalent? Chrome?


    Quote Originally Posted by Hexavalent View Post
    PICs, Basic Stamps!
    C'mon we're supposed to be Analog here - how about a couple 12au7's and a neon voltage reference

  10. #20

    Join Date
    Aug 2009
    Location
    Selah, WA
    Shooter
    Multi Format
    Posts
    255
    Best I can tell, the meter sensor that BetterSense used is sensitive to IR,,, just pop an IR filter in front of it and calibrate away.

    Quote Originally Posted by holmburgers View Post
    Please, somebody make an IR light meter.

Page 2 of 3 FirstFirst 123 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin