Photo Trek

Here is a special installment of Tips and Tricks to address a problem that I am seeing develop as people are looking at their photographs from the lunar eclipse tonight.  I know that this is a little late to fix the problems, but maybe I can help explain what went wrong.

Let me start out by saying that I didn't even attempt a shot of the lunar eclipse tonight.  First of all, the clouds were a bit too thick with only some spotty holes which would allow the moon to show through.  Second of all, I didn't have a long enough lens to really make it worth my time.  I would want a 400mm at least to try this shot.  My current 200mm (320mm equivalent) is just the wrong choice for this shot.

However, I've already seen the posts starting from those of you who tried to shoot the moon.  Actually, they are pretty good attempts, but I'm seeing a pattern developing here when the pictures are introduced.  One problem is the moon is not sharp, even though a tripod was used.  The second problem I've noticed is there appears to be static in the sky around the moon.  Reading these entries has prompted me to explain what is happening with your pictures here.

The first problem is the sharpness of the moon.  What you will notice is the moon appears fuzzy in the sky.  You know that the camera was still...you put it on a tripod...you did put it on a tripod didn't you?  So what could be causing the problem?  A couple of things could be working against you in this situation. 

First, the distance of the object and the lack of actual elements in the sky will lead to auto focus problems.  The moon can actually fool the sensors in even the most advanced camera.  The best way to combat that would be to use a manual focus setting and get the moon crisp in the viewfinder.  Usually, the infinity mark will suffice since the moon is so far away.

The second, and most likely cause of the fuzzy moon is your shutter speed.  When working in low light, you have to use a slow shutter speed.  How slow depends on your ISO/film speed, and aperture.  When you get into the slower speeds like 10-15 seconds, you will actually begin to see the moon move across the frame.  Even though the camera isn't moving the subject is.  As the moon moves across the frame, it is wiping its exposure trail from one point to another which makes the whole moon look blurry.  This is not as big of a problem with a regular moon as it is bright enough to make use of a faster exposure.  The best way to deal with this is to boost your ISO.

This brings us to your second problem that you are likely to encounter...that static in the dark night sky.  This is digital noise which is brought on by high ISO's or long exposures.  While this will sharpen up the moon since the shutter speeds are going to be much faster, this solution will introduce digital noise.  This is not a standard effect among cameras either.  Generally, DSLR cameras suffer from digital noise less due to a larger sensor.  When shooting film, the different manufacturers have different grain characteristics at a given speed.  Back to digital...if you are shooting with a point and shoot, you probably don't want to go higher than 400ISO, while digitals should be good up to about 800ISO.  These cameras have built in noise reduction, but that is accomplished by softening the image which leads back to the original problem.  You can also use a software application such as Noise Ninja, or Neat Image which will reduce digital noise in post production.  This also softens an image, but not near as bad as the in camera processor.

So, where does that leave us when trying to shoot the lunar eclipse.  It leaves us with compromises to make, just like in any photograph.  the noise is probably the easiest to deal with, and if you have one of the new pro model cameras, you can actually shoot up to 3200ISO without much, if any noise entering the equation.  You also want to avoid cropping the image as you lose resolution, which will increase the digital noise.  Another consideration is to avoid digital zoom since that will do all sorts of bad things to the quality of the photograph.  Like I said, i didn't even attempt the shot because I just didn't have a long enough lens to feel comfortable I could get the shot without some serious cropping later on.

You will notice that I have included many links in this entry.  They all link to my Tips and Tricks Journal, and you can find further explanations of these terms and concepts.  For those of you who have been taking notes since I began this feature, you hopefully have gotten a pretty good shot of the moon.  Regardless of your outcome, please feel free to post a link to your lunar eclipse shots in the comments section.

Written by Greg A. Kiser

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• #7 Comment from rbrown6172 
  2/21/08 5:21 PM | Permalink

  thanks for some more wonderful tips!  i do appreciate the time you take to educate jland shutterbugs.
  gina
• #6 Comment from midwestvintage 
  2/21/08 4:23 PM | Permalink

   Great tips, I only got one moon shot that ever turned out, not last night though.
  
                 Julie
• #5 Comment from rap4143 
  2/21/08 3:45 PM | Permalink

  Great information.  Where I live the trees were blocking my view, once in the clearing the clouds covered my view....:(.
  Betty
• #4 Comment from pharmolo 
  2/21/08 12:19 PM | Permalink

  Greg,
  Eclipse was invisible here in Scotland (rain all night), but I recognise some of the problems you highlight from the previous eclipse in March '07. Thanks for the T&T.
• #3 Comment from wwfbison 
  2/21/08 9:45 AM | Permalink

  Mine did not come out too well.  I did use my 400 lens.  I got the moon moving across the frame like a comet in one shot, which is actually pretty interesting.  I know my first mistake was no tripod...there was snow on the deck and I just didn't want to clear it all off and set it up.  I know, lazy photographer here.  ;(
  I learned a lot from your tutorial, thank you.
  Lisa