Case Study: Exposure at Night

One of our readers, Steven Ross, was kind enough to send an image to me as a Case Study. He is wondering why his image did not come out sharp, with some light spill and overexposure. Here is what he sent me:

Case Study

San Jacinto Monument at night

And his comments:

I used the camera on aperture priority mode and on a tripod but it appears that since the monument was being lit by spotlights the shutter speed was too long and the monument seems much brighter/overexposed compared to the rest of the scene.

I was just curious how to get the monument sharper when it is so much brighter than the surrounding dark area. It was roughly 20+ mins after sunset and pretty dark.

Here is a 100% crop from the above image (unprocessed):

Case Study Crop

100% Crop

As you can see, the image is indeed not very sharp. In addition, the monument is overexposed and there is that extra white line on the right hand side that does not look very appealing. So, what happened here? Here is the basic exposure information (the rest is preserved in EXIF):

Camera: Nikon D5000
Lens: Nikon 24-120mm f/4G VR
Focal Length: 34mm
Aperture: f/5.6
Shutter Speed: 15 Seconds
ISO: 200
White Balance: Auto

My Analysis: When dealing with very long shutter speeds (in this case it is 15 seconds), you have to make sure that the camera stays absolutely still on a sturdy tripod, from the beginning of the exposure, to the end. In the above case, the reason why there is an extra line on the right side of the monument, is because the camera was slightly moved from right to the left, most likely due to camera shake. Why from right to the left? Because the extra line is on the right side and not on the left. Steve probably did not use a remote camera release and his hand caused the camera to vibrate when he squeezed the shutter and then released his hand from it. Or perhaps he accidentally touched the tripod while the shutter was open. So sharpness in this case suffered due to camera shake. If I were shooting a 15 second exposure, I would have used a remote camera release, set my camera to “Mirror Lock-Up” or used a timer to minimize vibrations.

The second problem is overexposure on the monument. Now this one is a little tough to address in this kind of a situation. First of all, what is the right exposure? Steve shot on aperture priority mode and used Matrix Metering, which looks at the entire scene and tries to compute the exposure. The problem with Matrix Metering, is that it is not always very smart, since its purpose is to balance the whites and the blacks. To expose the monument correctly, I would have used Spot Metering and pointed at the monument, which would have given me a better exposure for the monument. But at the same time, a shorter shutter speed would have caused another problem – the sky and the reflection would have looked a little darker. There is really no “sweet middle” for these kinds of situations, but one thing you could do, is take two separate exposures – one at 15 seconds to expose for the sky, then another shorter exposure for the monument. Then, you could combine the two in Photoshop and using simple masking tools, get a balanced image. The good news, Steve shot the image in RAW, so not everything is lost – the overexposed areas are easily recoverable by just dialing -1 Exposure in Lightroom:

Case Study Crop -1

100% Crop with -1 Exposure

Also, you do not necessarily have to shoot two separate exposures in similar situations. The color of the sky can be changed through White Balance in Lightroom/Photoshop (by moving the temperature towards the blues) and its brightness could be adjusted a little by using “Fill Light”.

In terms of composition, it is typically tough to get creative with scenes like these. If he moved the horizon down a bit, it would have cut the reflection. Moving the horizon up would have been too boring. Obviously, moving the monument off the center would not have produced a good shot either, unless there were other buildings/objects around to be used for a better composition.

Here is the processed version of the image that I adjusted in Camera RAW:

Processed in Camera RAW

Processed in Camera RAW

And 100% crop:

Processed in Camera RAW Crop

Processed, 100% Crop

Now the white line on the right hand side is still there, but with 5-10 minutes of additional work in Photoshop, it could be easily removed.

Here is what I did in Camera RAW:

  1. Temperature: from 4150 to 3400
  2. Tint: +15 (as shot)
  3. Exposure: -1
  4. Fill Light: 15
  5. Blacks: 2
  6. Clarity: 25
  7. Tone Curve: Medium Contrast
  8. Sharpening Amount: 75
  9. Sharpening Radius: 1
  10. Sharpening Detail: 50
  11. Noise Reduction Luminance: 50
  12. Noise Reduction Luminance Detail: 100
  13. Camera Profile: Adobe Standard

Everything else is default.

Before and After:

Before After

Before After

If you would like to send your picture for a case study, please send me an email through our Contact Us page. I will reply to your email, so that you could attach the original RAW/JPEG file.

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

Comments

  1. 1
    ) Bobby
    December 2, 2010 at 12:58 am

    This is very helpful Nasim, thank you!

    • December 7, 2010 at 7:46 pm

      You are most welcome Bobby, glad you found it useful.

  2. 2
    ) Mike
    December 2, 2010 at 12:59 am

    Your site is very educational. Thanks for taking to help us make better pictures.

  3. 3
    ) Emin
    December 2, 2010 at 2:34 am

    Hi Nasim,

    Thanks for your case study and tips. It helps me a lot.

  4. 4
    ) Eduardo Siqueira
    December 2, 2010 at 5:35 am

    Very helpful Nasin. The D5000 has Lock-up Mirror feature? Where can I find it?

    • December 7, 2010 at 7:50 pm

      Eduardo, seems like D5000 only has mirror lock-up for cleaning the sensor. For taking pictures, please use a timer instead, which will also help with reducing camera shake when used on a tripod.

  5. 5
    ) Suelci Pimentel
    December 2, 2010 at 5:46 am

    Oi Nassim !
    Sempre que leio seus comentários , aprendo muito e procuro tirar o melhor proveito deles.
    Muito obrigado pelas dicas.
    Um abraço ,

    Pimentel

    São Paulo – Brasil

  6. 6
    ) Steven Ross
    December 2, 2010 at 6:14 am

    Hi Nasim,

    It’s Steven Ross (my pic above). Wow you are pretty quick and your advice is second to none. To date I have yet to find a more informative site online, keep up the great work.

    I cannot believe how much better you were able to make the photo with a few adjustments in photoshop. I always shoot in RAW at the advice of your site to allow for some post processing corrections, if possible.

    I will also add that I used a tripod with a center post raised (don’t worry I have since ordered a new one to rectify the camera shake issues). I will also be getting the wireless remote asap to assist with low light situations as I have had any big problems with camera shake in daylight.

    Thanks you so much and I hope other send in pics as well. I will continue being a faithful visitor to your site and already many entries several times lol.

    Steven Ross

    • 7
      ) Steven Ross
      December 2, 2010 at 6:16 am

      Me again,
      please ignore the typos in my response lol. sometimes my brain goes faster than my fingers can type.

      • December 7, 2010 at 7:52 pm

        Don’t worry, I do not pay attention to typos and I make lots of errors myself :)

    • December 7, 2010 at 7:52 pm

      Thank you for your feedback Steven and I am glad that you found the above case study useful :)

  7. 8
    ) Rahul
    December 2, 2010 at 8:24 am

    That’s a lot of detail obtained from RAW !

    • 9
      ) Rahul
      December 2, 2010 at 8:26 am

      However, I’m not sure everyone would like the result after WB change, the original image has a bit of warm orange glow in the sky, the processes image is much more blue.

      • December 7, 2010 at 7:53 pm

        Rahul, I agree – I only did it according to my own taste :) The good thing is, we can change the colors as much as we want when shooting in RAW.

  8. 10
    ) Mark
    December 2, 2010 at 10:18 am

    Great comments a advice, very useful. From recent experience of my own it is also surprising how little wind it takes to move a camera on a fully extended tripod – although looking at the water that was probably not the issue here.

    • December 7, 2010 at 7:54 pm

      Thank you Mark! Yes, especially when shooting at long focal lengths!

  9. 11
    ) Nina
    December 3, 2010 at 5:35 pm

    The shaking could also be from not turning off the VR function on the lens which is important to remember when the camera’s on a tripod. :)

    • December 7, 2010 at 7:55 pm

      Nina, that’s true and thank you for the tip – VR should always be turned off when using a stable tripod.

      • 24
        ) Ravi
        December 8, 2010 at 8:39 am

        I think some lenses are tripod-aware. For those lenses, it’s not necessary to turn off VR, I guess.

  10. 12
    ) Michel
    December 3, 2010 at 6:20 pm

    Bravo !

  11. March 17, 2011 at 12:40 am

    I really like your website, very educative. I would like to subscribe for your post via email.

    wildlifeodyssey@gmail.com

  12. 26
    ) Susan
    April 28, 2011 at 7:16 am

    The amount of detail you retrieved from the raw file is incredible. I am not shooting RAW yet because I only have a small SD card, but I am looking forward to when I can. I have the Nikon D5000 and it is strange that it does not have mirror lock, yet micro4/3 cameras (which I believe don’t actually have a mirror?) do have mirror lock up – how weird is that?!

  13. 27
    ) Kai Rader
    October 31, 2011 at 8:47 pm

    Hi Nasim,

    Would you also suggest a smaller aperture to maximize depth of field for a long shot like this?

    Thanks,
    Kai

  14. January 16, 2012 at 7:03 pm

    Great article and an awesome website in general.

    When taking long exposure or even shots at slow shutter speeds I like to use the delayed shutter release on my Nikon D90. I think all Nikons have this function. Look At d10 (exposure delay mode) under the custom settings menu. This will delay the opening of the shutter for about a second, which gives the camera a little time to “settle down”.

    Also as mentioned, a shutter release is extremely helpful. I use a cheap $30 wireless remote type of release, which is cool because I can set my camera outside, go in the house, and still snap off a photo. A remote trigger is great for capturing shots of birds at the bird feeder (set the camera on a tripod, set the focus, hide or go in the house, and shoot the shot when the bird approaches the feeder) or in a situation when it is cold outside and you want to shoot some time exposure shots for star trails from the warm indoors.
    Tom
    Colorado Springs

  15. 29
    ) Meenal
    July 22, 2012 at 4:13 pm

    I recently bought Nikon J1 with 10-30mm and 30-110 mm lens. I am confused as to which lens would be better to take pictures at a convention center stage performance I have to attend to. Any advise would be really helpful.

    Thanks

  16. 30
    ) olando
    November 10, 2012 at 6:37 pm

    very informative sir, im learning alot from your site. thanks so much

  17. 31
    ) Eswar
    February 19, 2014 at 11:56 am

    Hi Nasim,

    I recently started following your site. Your case studies are very informative.
    About this particular case study, the picture was taken with an aperture of 5.6 . Is this okay for this particular scene. I thought this kind of scenes look better when they were shot at an aperture of 11 to 14. What observed lately is when we take this kinds of picture with larger aperture details in high lights are blown away. May be I am wrong.
    Awaiting your comments. Thanks.

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