How many moons orbit Earth? And what time is it? And am I dreaming?
These were the thoughts that crossed my weary mind when I woke up and looked out the window of my hotel the other day, to see this:
There were four moons in the sky, with two of them overlapping each other, and with each varying in brightness.
Fortunately, I didn’t panic, because I knew exactly what was causing this visual phenomenon. And demonstrating my somewhat nerdy tendencies, I also immediately realized this was a perfect example of a photographic issue that has come up on many occasions when I’m working with photographers in the field, especially at sunrise or sunset.
The reason for the interesting aberration in the photo above is that there was more than one pane of glass in the window. In fact, there were four, since there were two double-pane windows making up the entire window assembly. The multiple reflections of the moon were caused by the multiple panes of glass.
And this perfectly illustrates one of the reasons I recommend (whenever possible) against the practice of using filters in front of your lens when you’ll be including the sun (or other bright lights) in the frame. Just as the multiple layers of glass in the hotel window caused multiple moons to appear, so can those filters in front of your lens cause multiple “ghost” suns to appear in the frame.
That’s not to say you can’t get great photos with the sun in the frame and filters in front of your lens. And that’s not to say that in some cases the filters may add to the result, or even enable images that might have otherwise been impossible. It is just saying that avoiding those filters can sometimes be advantageous.
Of course, in this case, since those “extra” filters were keeping out the freezing cold air, I didn’t mind having the extra glass between me and the view. And I most certainly didn’t mind the aberration that resulted.