Nikon 105 2.8 macro
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I don't have the lens but I assume it changes when focussing at short distance (ie macro distances)?
This is normal for most lenses and it down to physics. This explains it....
http://www.cambridgeincolour.com/tutorials/macro-lenses.htm
(look for effective F-stop)
This is normal for most lenses and it down to physics. This explains it....
http://www.cambridgeincolour.com/tutorials/macro-lenses.htm
(look for effective F-stop)
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Yep your correct, basically the closer you go the more the lens stops down, and TBH you don't really want to be using f/2.8 anyways if your going to shoot extremely close
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Not the most experienced Macro togger as I haven't got out with my macro lens yet that much
but I would say about f/11, f/16 and onwards for small small subjects...
OP
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Not the most experienced Macro togger as I haven't got out with my macro lens yet that much
Thank Joe...
Hi
Yup the f# changes the closer you get. First reason, because the focus plane is so small you wont be get the focus unless by accident, miniscule wobbles = missed focus. 2nd I think I recall something about the construction of the lens, that it moves the aperture because of the way it is built/
As to macro shots, unless you are stacking, probably using f11 and higher number...
Yup the f# changes the closer you get. First reason, because the focus plane is so small you wont be get the focus unless by accident, miniscule wobbles = missed focus. 2nd I think I recall something about the construction of the lens, that it moves the aperture because of the way it is built/
As to macro shots, unless you are stacking, probably using f11 and higher number...
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I believe they are, and your Canon set up might not have because you never probably went close enough to a subject?
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The f/number is only correct at infinity focus, and it rises as the lens is focused closer. The change is barely measurable at normal range, but when you get really close as with macro, it begins to rise dramatically. At 1:1 image size, it will have risen exactly two stops; Nikons report this correctly, Canons don't, though TTL metering automatically compensates.
So at 1:1, an f/2.8 lens should be reading f/5.6, but from memory I think the Nikon 105/2.8 reads f/4.8 or something? This is because the internal focusing of the lens also reduces the effective focal length at very close range, so what you have (rough estimates) is something like a 90mm f/2.4 lens at 1:1, that then reads f/4.8 - if you follow!
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Checking some of mine shows anywhere between f10-f20.
Nod
Tootles
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There's no single answer to that! If you want to isolate a tiny portion in sharp focus, stay wide open but if you want a bit more of the subject in the area of acceptable sharpness, stop down. If you want/need the whole subject to be sharp (assuming a 3 dimensional subject like an insect) you'll probably need to do some focus stacking - good luck and have fun!!!