It's that time of year again, the Fawn Lilies are coming out in the woods behind my house. These pretty little flowers make great subjects as they hold perfectly still. Ha ha!
I'm finding an interesting thing with my Nikon 18-300 lens, most zoom lenses get clearer and sharper stopped down a little with a smaller aperture as opposed to wide open with a larger aperture. This is definitely not the case with this lens as it gets it's best results at 300mm wide open! I can see I'm going to have to spend some time playing with this lens at various focal lengths and apertures to see what works best.
Des fleurs si délicates....
ReplyDeletePierre
I like the third photo the best because it has the water drops on the leaves.
ReplyDeleteI haven't noticed any problems at any aperture with my 28-300mm lens. I might pick up just a touch of vignetting at 300mm and f5.6 but it's nothing a little bit of cropping won't fix. For an all around everyday lens I don't think it could get much better and I think your 18-300mm will be the same. YOu just can't beat Nikon glass.
The lens handled the delicate shots with ease. I've found my Nikon lens 55mm/200mm also renders the clearest image at 200 wide open but with very little change at 150mm. You hit the nail on the head, "get familiar with your equipment!"
ReplyDeleteSuch a beautiful flower.
ReplyDeleteThe reason your picture is sharper when your aperture is wide open because the DOF. The way I understand the DOF is that To maximise depth-of-field and have as much sharp as possible use a wide-angle lens, set a small aperture and stand back from your subject. To minimise depth-of-field with only a small zone of the scene sharp use a telephoto lens, set a large aperture, and get closer to your subject.
ReplyDeleteThere're 3 main factors that can be used to control depth-of-field
1 The aperture.
There's a simple, direct relationship between aperture and depth-of-field - the smaller the aperture, the more extensive the depth-of-field.
So if you want to keep as much as possible sharp, you should set as small an aperture as possible - preferably f/16, or even f/22 if your lens offers it.
Depending on lighting conditions and your film stock, you may need to use a tripod or some other form of support at such small apertures, as the resulting long shutter speeds create a risk of camera-shake.
If, however, you want to concentrate attention on just one part of the scene, and throw the rest out-of-focus, you should select a large aperture. Exactly how large this can be depends on the maximum aperture of the lens you're using. On a 50mm standard lens it will be f/1.7, f/1.8 or f/2, but on a standard zoom it will typically be f/3.5 or f/4.5.
For general picture-taking, when you want most of the picture to be in focus, you might want to set a middling aperture of around f/8 to f/11.
This is what a program exposure mode sets when left to its own devices Whenever possible you should take control of aperture selection and use either an aperture-priority or manual mode.
2 The focal length of the lens.
Attach a wide-angle lens and you'll benefit from extensive depth-of-field, which makes it easy to keep everything in focus. The wider the angle-of-view, the greater the depth-of-field. Choose a telephoto lens and the depth-of-field is immediately more limited. The longer the focal length, the more restricted the zone of sharpness is.
3 The Camera-to-Subject Distance.
For various technical reasons, the closer you get to the subject the more limited the depth becomes. In fact, when shooting close-up subjects it can extend to just a few millimeters in front of and behind the subject.
Thank you Q for this information!
ReplyDeleteI am familiar with the first part to do with the aperture size effecting the depth of field but didn't know about your next two points, the focal length of the lens and the distance to subject.