Lori Carey Photography

Saturday, December 15, 2012

Shooting Sunstars for Creative Intent

Trona Pinnacles silhouette with sunstar
Late afternoon at Trona Pinnacles

I've been playing around with bringing the sun into some of my desert photos to give a better feel of the desert environment. The strong backlighting in this scene at Trona Pinnacles National Natural Landmark caught my eye throughout the afternoon and I shot it a number of ways, but this image with the sunstar is the one that felt right. This is what the desert looks and feels like in the late afternoon on a winter day.

Sunstars are relatively easy to achieve. They are caused by diffraction as the light enters the lens and the number of spikes you see is determined by the number of aperture blades in your lens. Each straight edge of the iris creates a pair of spikes, however if your lens has an even number blades you will only see one spike per blade because the blades are parallel and the spikes overlap.

To shoot sunstars:

- Use a small aperture (f16 or smaller, and remember the bigger the number the smaller the aperture)

- Remove any filters because they will typically add too much flare as the light passes between the filter and the lens

- Because you are using a small aperture you will want your lens and sensor to be spotlessly clean unless you want to spend a lot of time in post cleaning up dust spots

- Although it is possible to achieve sunstars when including the entire sun in the frame it is much easier to achieve good results if you have part of the sun blocked or hidden. Try having just a bit of sun peeking out from behind a rock or tree, or leaving most of it out of the frame as I have done here.

- Many tutorials recommend using Aperture-Priority. The problem with this is that the bright sun will usually trick your camera's exposure meter into underexposing the scene. It's better to shoot in Manual mode, bracket and determine the correct exposure that will achieve your creative intent. If you don't want your foreground underexposed you will need to use a slower shutter speed than what your camera recommends.

- Using a small aperture in low light situations usually means you will be using a slower shutter speed...which means a tripod is a must.

- Adding contrast and clarity selectively in post can help make the spikes sharper if that is what you want. Again, it depends on your creative intent. In the image above I did not want a sharply defined star and chose to give the impression of sun rays.

This same technique is used to make points of light appear as stars in night photography, especially cityscapes.

Have you shot any sunstars that you want to show off? Feel free to link to them in the comments!

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