Changing Aperture on Sigma Lenses with a D50?

[maniladude]

Hello all,

I have just acquired a Nikon D50 body and Sigma 28-300 lens, and am a bit confused as to how to change aperture on the setup. After I noticed that my shifts in aperture were not producing the stark depth of field changes that I had seen produced by other photographers, I consulted the lens manual which told me that I had to manually change aperture via the lens' aperture ring. When I try to do this with my D50 the camera reports that the lens aperture is improperly set and does not let me take the picture.

Any assistance that Nikon or Sigma owners could lend me would be appreciated, although I do get that this is a "newbie" question..

[buruburu]

With the D50, you need to set aperature on the lens to the highest f value (narrow), and change the aperature setting through the camera. Make sure that you're in the right mode, A or M.

If you're in A, just simply rotate the command wheel, and you'll see the aperature change. For M mode, you'll need to hold down the aperature button in front of the shutter release button, and then rotate the command wheel.

[maniladude]

I have tried this and am not seeing results in terms of changing depth of field. Is this due to a limitation of the lens? (the box says it's an F3.5-6.3 lens)

[Ray Schnoor]

I have tried this and am not seeing results in terms of changing depth of field. Is this due to a limitation of the lens? (the box says it's an F3.5-6.3 lens)
By saying changing the depth of field, I assume that you mean that you want a shallower depth of field. To get a shallow depth of field, you need to open the lens to the widest aperture possible. Usually, this means f/2.8 or wider. With the lens you mention, the widest aperture is f/3.5 at the wide end and f/6.3 at the long end. You may not be able to get as shallow a depth of field as you want with this lens.

Ray.

[maniladude]

Thanks for making all of this lens stuff make a lot more sense! I wish I'd known that prior to buying the lens, but I'm still hoping to get some blur with experimentation.

[George Riehm]

Try shooting at 75mm and up, at the lowers aperture number the lens will allow (probably f/4.5 to f/6.3. You should get the bokeh you are looking for.

Any AF lens with a manual aperture ring will need to be locked in the smallest aperture listed on the ring (usually f/22 or more).

If you bought the 28-300 recently Mybe you should consider returning it for an 18-200. Just a thought, as the 28-300 is not the best general purpose lens, and the wide agle capability leaves a lot to be desired.

Bon photo.