1. Welcome to NikonCafe.com—a friendly Nikon camera & photography discussion forum!

    If you are thinking of buying a camera or need help with your photos, you will find our forum members full of advice! Click here to join for free!

The D3 and the Expodisc

Discussion in 'Nikon FX DSLR Forum' started by MikeA, Jul 20, 2008.

  1. MikeA

    MikeA

    316
    Aug 26, 2007
    Left coast, USA
    From a different message thread:

    I gave it another try this afternoon -- first, a shot in the shade with Auto white balance. The light seemed fairly warm even though I was on the shaded side of the house. The Auto white balance did a reasonably good job. I wouldn't need to do much WB correction later. Then I tried the Expodisc. I made sure that it was placed over the lens with the correct side outward. I changed WB to "Pre," pressed and held the WB button, then took the reference shot. The D3 responded "Good." Then leaving the D3 on "pre," I took another shot. The result was horrifically blue -- just as happened before.

    Either I am doing something very wrong with the custom-WB procedure, or I can no longer use the Expodisc...
     
  2. Same here!

    I tried to use my Expo Disk on my D3 to set a WB in a church that I will be shoot in with the same type of results. The church has a mixture of flor and incond bulbs. I wanted to get a "pre" set up so when I shoot there it would be just a matter of dailing the pre up and fireing. But the Expo came out orange on three diff tries. That AWB was real close. I will try a white card and see if I can get a better setting. The Expo worked well on the D2Xs but not the D3. I was wondering if the new firmware had anything to do with it.:confused: 
     
  3. MikeA

    MikeA

    316
    Aug 26, 2007
    Left coast, USA
    Yeah, I'm finding this confusing also. I could write to the Expodisc people, but I found in the past that they weren't very responsive. No problems with custom WB with that system and my 5D, but this is a different matter entirely! I could live without the thing but I would hate to have spent all that money for nothing. I sure am interested to find out why it's so far off the mark. (And why should this be noticeably different from setting custom WB with a grey or white card?) It will be especially interesting if others with D3s are getting perfectly good custom WB with their Expodiscs.

     
  4. pluka

    pluka

    45
    Dec 30, 2005
    Mike,

    I've tried several scenarios today - outdoor, florescent, incand, mixed with the expodisc and couldn't repeat your problem. It was always close to the autoWB and sometimes a bit more accurate, but I'm not sure using the expodisc is worth the trouble for the small benefit. I'm using a D3 firmware 2.0and a 28-70 lens.

    Paul
     
  5. MikeA

    MikeA

    316
    Aug 26, 2007
    Left coast, USA
    Thanks for checking it and reporting what you found out. I've seen this happen with two different lenses now. I have to conclude that I'm just doing the custom-WB procedure wrong, somehow. I'll go back through the manual and make sure I understand the procedure, and try again...
     
  6. Are you pointing the lens and expodisc toward the light source?
     
  7. MikeA

    MikeA

    316
    Aug 26, 2007
    Left coast, USA
    I certainly thought so at the time. But clearly I've done something very wrong so I'll give it another shot...
     
  8. PedroS

    PedroS

    259
    May 4, 2008
    Portugal
    expodisk

    I'm getting the same results...
    Just using the expo to find if the D3 sensor's need cleaning.
     
  9. MMarz

    MMarz

    Sep 15, 2007
    Long Island, NY
    To expand on Greg's question..

    when using the expodisc, you must be metering the light falling on the subject, not the light reflected off the subject. Walk over to your subject, turn and face the light source and set the custom WB..

    I use it often and it works perfectly. Once you set the custom WB the body will retain that setting until you either change to another standard WB setting or set a new custom setting.
     
  10. jfrancis

    jfrancis

    May 8, 2005
    Orlando, FL
    This is important. I forgot that during a shoot last week in horrible mixed lighting conditions and the result was nasty. Fortunately, the D3's AWB nailed it . . . :eek: 
     
  11. Greg and John,
    I going to try the old Styrofoam cup trick, when I get some play time. I have tried the Expo here at the house with the same results, who knows. The new and improved AWB is right on most of the time. I guess the Expo is going to be a D2Xs accessory.
     
  12. MikeA

    MikeA

    316
    Aug 26, 2007
    Left coast, USA
    Turns out to be user error here, too. I was too hasty with the thing and did not orient it correctly. Seems to be doing the job after all. I wonder if some day the manufacturers can make this even faster/easier to do. For example: place a small sensor somewhere on the top "deck" of the camera. Leaving the camera in its normal upright position and with the ambient light falling onto this hypothetical sensor, you'd press and hold a custom WB button. Almost immediately the custom WB would be set. IOW, the main sensor itself would no longer be needed -- there'd be a kind of color-temperature meter existing separately within the camera. No more having to hold down the WB button, wait for the 'start' indication, point the lens at something, activate the shutter, and then check for 'Good' on the display. (But this is not exactly a complaint about Nikon's current custom WB procedure. For me, coming from the 5D, the way Nikon does it is far more convenient and it was among the reasons I decided to switch systems.)

    I would think there's enough computing power in these cameras to do such a thing. But I don't know if it's realistic to expect that they could add a small color-temperature meter of the kind I'm suggesting -- without having to boost the price of the camera quite a bit.
     
  13. pforsell

    pforsell

    Jan 15, 2008
    Doesn't the D2 series cameras have this on top of the prism housing, the white "eye" ? It is used in AWB though not for PRE afaik. For some reason Nikon decided that D3 doesn't need it, perhaps they didn't want to develop it further or thought that the sensor-based AWB is better.
     
  14. gvk

    gvk

    388
    Jun 17, 2005
    Mystic, CT
    On the D2X, the sensor on top of the prism housing could be used to preset white balance based on the ambient lighting. If I recall correctly this was accomplished by pressing the Func button while PRE was flashing, instead of using the shutter release button with the camera pointed at a neutral card. I did not use this much, but this ambient sensor preset seemed to produce results similar to the Expodisc on the D2X.

    The D2X manual also states that this ambient sensor is used along with the camera's 1005 pixel RGB sensor in setting auto white balance.
     
  15. MMarz

    MMarz

    Sep 15, 2007
    Long Island, NY
    Peter, it does have the Custom WB sensor on the prism housing..but for the life of me I have not been able to get a good reading on the custom setting.. After a bunch of posts here as well as elsewhere, I finally gave up on it. :mad: 
     
  16. I got the CBL and find it really does work.
     
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.