tokina 100mm 2.8 nikon f stop question
Feb 5, 2015 13:54:21 #
I recently bought a used Tokina 100mm 2.8 macro for my Nikon D90. It is a really nice lens, and I'm happy with the results I'm getting. One thing that I've noticed is sometimes I can't get it to stop down to 2.8. I doesn't always happen but it does frequently. Is this normal behavior or is there something wrong with the lens?
Feb 5, 2015 14:09:50 #
What mode are you shooting in? If it is full auto I am thinking there may be too much light for the lens to need to stop down that far. Possibly your ISO is too high or shutter speed too low. I know others will offer more expert advice than I am giving but it is a start.
Feb 5, 2015 14:17:14 #
When you look through the view finder of the camera, the aperture shown is the effective f/stop.
If the lens focus is changed from infinity to minimum focal distance, the effective aperture will change from f/2.8 to f/5.6.
Is that what you are seeing?
If the lens focus is changed from infinity to minimum focal distance, the effective aperture will change from f/2.8 to f/5.6.
Is that what you are seeing?
Feb 5, 2015 14:23:24 #
quite possibly. I just read that at 1:1 focus distance the smallest fstop available would be 5.6. I appreciate the reply, and am relieved to know that this is normal behavior for a macro lens.
Thanks.
Thanks.
Feb 5, 2015 14:24:33 #
dennis2146 wrote:
Sorry I'm new at this and in future I will use quote reply. Thanks.If you click on, Quote Reply, before answering we will know who you are talking to. Believe me, it helps a lot.
Feb 5, 2015 14:30:02 #
Feb 5, 2015 16:06:24 #
OldTigger has it correct: Aperture at infinity is f/2.8, but same aperture at MFD is effectively f/5.6.
Read more here:
FAQ: What is Effective Aperture for Macro?
http://www.uglyhedgehog.com/t-114166-1.html
Read more here:
FAQ: What is Effective Aperture for Macro?
http://www.uglyhedgehog.com/t-114166-1.html
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