For me, its just a personal preference... I almost always shoot in aperture priority whether doing portrait, sport, or landscape.

In portraits, I want to control the depth of field to isolate the subject from the background. For landscape I want to ensure I have enough depth of field to have enough of my subject in focus. For action/sports, like in portraits I want the subject isolated by a large aperture limiting depth of field but also I want the fastest shutter speed available, which will always be at the largest aperture setting for your lens. Larger the aperture = the faster the shutter speed.

I'm more comfortable isolating my desired aperture and letting the shutter speed float. If there isn't enough light to get a fast enough shutter speed to stop the action, say 1/250th or faster, then I leave aperture alone and crank up the ISO until I'm shooting at a fast enough shutter speed to freeze the action.

Also, some lenses have lower image quality at the largest and smallest apertures. At small apertures you get chromatic abberations, at larger apertures you may have less resolution. The sweet spot of nearly every lens is in the f5.6-f8 range. Depending on how good the lens is, the differences in image quality at different apertures may be more or less of an issue - a pro quality lens performs well at all apertures where an entry level lens performs less consistently across the aperture range.

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I've found that using shutter priority mode, can cause big swings in aperture, which for my preference is a bad thing...

As an example picture a day where the sun is moving in and out behind clouds, or even better part of the field is in bright sun and part is in a shadow (I'v taken pictures where everything beyond the mound is sun, but the batters box/home plate is in full shade. If I lock a 1/500th shutter speed I may get an aperture of f13 on a player in the sun which for me is an undesirable aperture... Then I track over to a player in the shade, but I may not have a big enough aperture at that shutter speed resulting in a picture thats underexposed at f4.

If I lock in a f4.5 aperture, I might get a 1/2000th second on the player in the sun and a 1/250th on a player in the shade. Both photos are acceptable, where as in shutter mode neither was acceptable.

Obviously, if lighting is consistent like in a basketball court, its not as big of an issue and shutter speed priority may not create many severe aperture fluctuations... but for me, i'm mostly outdoors and there is not consistent lighting very often. Aperture just works better for my style. If shutter works better for your settings and style, then stick with it.




Quote Originally Posted by frikativ54 View Post
Why do you recommend aperture priority mode over shutter priority mode? I usually use shutter priority on 1/250 with my ISO at 1600 for court-side photography. I understand your point about the flash, but my lens simply doesn't let in enough light to do non-flash pictures.

Perhaps I should buy another lens, but I do not have enough money to afford that kind of upgrade. Especially when I'm buying a new nature photography lens, which is my true passion. So - I am trying to make due with what I have, my Nikkor 18-105 mm lens.

Please explain how you work aperture priority mode and what are the advantages over shutter priority mode?

-Frik