D300... JOB NR? Huh!?

Discussion in 'Nikon' started by rene|4, May 20, 2008.

  1. Hi! I was taking a few long exposure shots of the moon and was chenging the
    exposure value after every shot. When I set it to EV-5 the camera took the
    picture and after the mirror went down again the camera was frozen for a few
    secs, just like a PC. (I hope is not runing Vista :) ) Inside the view finder I
    red "Job" followed by what I think was "nr". The camera wouldn't do anything at
    all, not even display the image in the display. I think it also happened at EV
    -4 but it didn't happened at EV -3, -2 or -1. It happened many times. I got home
    and look in the manual but I can't find what "Job nr" stands for! Any help?
    Thank you!

    Here is the picture if you guys in the EU and the States want to know in advance
    what the Moon will look like tomorrow evening (May 20th). I need a better lens
    collar, I was using a pack of cigarettes and a Nikon camera cap under the AF-S
    300 f/4

  2. I forgot the picture!
  3. You have your D300 set for in camera long exposure noise reduction. And the camera is doing the noise reduction processing (the JOB nr" message). Since much of the area (the area around the moon) in your photo is essentially at a very low exposure level it has a lot of work to do.
  4. Is that what it was? Makes a lot of sense now! Thank you Ellis!!!!
  5. Here's a strange thought.
    Since the moon is lit by the sun, shouldn't the exposure value be about the same as
    the earth in daylight... therefore, why do you need such a long exposure????
  6. A following question..... Since I don't use Capture NX but Aperture do I need to have the long exposure noise reduction thing set in the camera? Aperture is not supposed to read the camera settings, right? Thanks again!

    John.... I don't know! I'm just learning! I was shooting on aperture priority at f8 but at EV -1 the Moon was over exposed, just a white round thing and no detail on it. So I kept decreasing the value until I got something I can live with. If there is a better way please tell me! Thank you! Rene'
  7. Depends on the exposure, John. If you use a small aperture and low ISO, the shutter speed could be fairly long.

    The full moon itself is fairly bright, but it's not that simple. Digital gives us different ways to skin this particular cat, including ignoring the ETTR mantra and leaning toward the left side of the histogram to eliminate any risk of blown highlights, with post processing to render a full moon with mostly upper midtones and an absolutely black surrounding sky.

    Normally a full moon would be around EV 14, pretty bright. But subjects illuminated *by* the full moon would be around EV -2 to -3.

    I'm guessing that since Rene was using a 300mm lens with 1.5x teleconverter on a 1.5x dSLR, he was still getting a lot of black space around the moon. Anything but spotmetering would read this as well under EV 14, which probably accounts for what he described, shooting at EV -2 to EV -5.

    I'm curious about his in-camera settings and post processing to get the finished photo he's displayed.
  8. Long exposure noise reduction is a technique that can only be done in the camera. Ellis had the explanation a little bit off.

    Long exposure noise is reduced via a technique called "dark frame subtraction". This means if you shoot a 4 second exposure, the camera takes that 4 second exposure, stores it in memory, then closes the shutter and takes another 4 second exposure of the closed shutter, to get something that should be totally black, a "dark frame". This dark frame should contain pretty much the same amount of noise as the "real" picture taken just before it. The camera then subtracts the dark frame from the real frame, to get an image with less noise..

    The only way to do that outside the camera is to have both a real frame and a dark frame. Shoot the moon, then cap the lens and shoot your own dark frame the same exposure time, then use PhotoShop or a more sophisticated program to do the math. A helpful hint, Apple-ture is not the kind of program that you can use to do advanced techniques, stick to letting the camera do it.

    Now, if you want to expose the moon properly, use manual, not aperture preferred, and read your histograms. Also try the spot metering mode, and expose 1 stop more than what the spot meter says. Matrix metering doesn't really work on the moon, because it's a small white spot in a big black field. The camera will do OK, if you get the moon to fill the frame like a face. But with a 300mm f4 on a 1.5x TC, you've only got about 1/4 the magnification you'd need before the camera would really figure out how to expose the moon.

    You need short exposures to get a sharp moon. Believe it or not, the moon moves, if your exposure runs into the seconds, the moon will move enough (only takes a couple of pixels) to smear the image.
  9. On the top of my head, exposure of full moon is roughly 1/250, f11, ISO 200, adjust from there based on the moon's position. With these times, you don't need long exp. NR.

    Be careful with long exposures...the moon MOVES and may thus blur your picture ;-)
  10. Lex.... "I'm curious about his in-camera settings and post processing to get the finished photo he's displayed."

    I don't know what to make out of that but I will try to explain...

    I'm really bad at PP. I hate it!

    To start with A/priority, 1/80 at f8, ISO 200, exposure compensation -5.0 ev, w/b auto. (A pack of cigarettes and the camera cap between the lens and the foot of the lens collar coz I was having serious blurring)

    In Aperture 2 adjustments:

    Definition 0.5
    Highlights 10.1
    Color Yellow saturation -1 Range 1.88
    Sharpen Intensity 0.70 Radius 0.80

    And some serious cropping.

    I hope that gives you an idea of what I did. Rene'
  11. RAW file if anyone wants to take a look:

  12. By the way- measuring exposure of a bright object in black surrounding is not going to work well unless you use spot mode. The spot should be smaller than the moon^^. In this case you should get perfect exposure.
  13. Yup, spotmetering with even a 300mm isn't enough to cover the moon with my D2H. It's still a bit of guesswork, informed by a standard EV chart for known lighting situations.
  14. I would think with a 300mm on a full moon, the spot reading should give you a pretty
    accurate number. If the clouds (fog) ever burn off here, I'll go out and compare a spot
    meter reading vs. the spot reading in my d300 and let everyone know how they
    compare. Unless someone that can actually see the moon beats me to it.
  15. I was about to ask same question. I to did a long exp of the moon last night and had same problem. It does make alot of sense now that I think about it. LOL

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