f stops
Mar 19, 2024 23:12:50 #
Bohica
Loc: SE Coast of NC
I dont usually shoot wide open so never noticted my Nikkor 50mm f1.4 register f2.0-32 instead of f1.4 -22 and my 50mm f2.0 -16 register f2.8-22. is this because of the crop factor on my D7100?
Mar 19, 2024 23:18:05 #
Bohica wrote:
I dont usually shoot wide open so never noticted my Nikkor 50mm f1.4 register f2.0-32 instead of f1.4 -22 and my 50mm f2.0 -16 register f2.8-22. is this because of the crop factor on my D7100?
Not normal. Try reinstalling the FW.
Dont bother with "two-button reset."
You would regret the latter.
Mar 20, 2024 00:03:55 #
Bohica wrote:
I dont usually shoot wide open so never noticted my Nikkor 50mm f1.4 register f2.0-32 instead of f1.4 -22 and my 50mm f2.0 -16 register f2.8-22. is this because of the crop factor on my D7100?
Crop factor.
When using a FX on a DX body, you use only the circle of diffusion center. The camera recognize that and modifies the data as needed.
Mar 20, 2024 00:21:09 #
Orphoto
Loc: Oregon
Another possible cause is that they are older lenses without chips and you didn't enter the non cpu data for their maximum apertures. If instead you are coasting on another entry with a maximum of f2, then the camera won't know any differently.
Mar 20, 2024 03:57:40 #
Bohica wrote:
I dont usually shoot wide open so never noticted my Nikkor 50mm f1.4 register f2.0-32 instead of f1.4 -22 and my 50mm f2.0 -16 register f2.8-22. is this because of the crop factor on my D7100?
Adjust your focus distance and see if there's a difference in indicated max aperture.
Mar 20, 2024 05:34:51 #
Bohica wrote:
I dont usually shoot wide open so never noticted my Nikkor 50mm f1.4 register f2.0-32 instead of f1.4 -22 and my 50mm f2.0 -16 register f2.8-22. is this because of the crop factor on my D7100?
Are these lens AF lenses? If they are MF lenses then you have to tell the camera the maximum aperture of your lens. If you lie it wouldn't know.
Mar 20, 2024 10:09:50 #
Bohica wrote:
I dont usually shoot wide open so never noticted my Nikkor 50mm f1.4 register f2.0-32 instead of f1.4 -22 and my 50mm f2.0 -16 register f2.8-22. is this because of the crop factor on my D7100?
Something else is going on...your camera will take the settings from the lenses...no crop factors are factored in that way.
If you have an f/1.4 lens...it should read as f/1.4 in your camera. It won't be in the final image (crop factor).
Mar 20, 2024 10:30:45 #
tcthome
Loc: NJ
Grahame wrote:
Adjust your focus distance and see if there's a difference in indicated max aperture.
On my Nikon MC 105 G IF ED 2.8 lens stops down to f-3.2 when at minimum focus distance of 11"so maybe ??? If I back up say to eg., 18-24" it will open up to the f-2.8.
Mar 20, 2024 10:32:19 #
Bohica
Loc: SE Coast of NC
A quick reply to all, lenses are both manual and AF and only listed two but seems to be that way on all my fx primes.
Mar 20, 2024 11:38:42 #
Not having the lenses and body, I can only 'recollect' there were some quirks in the D7100 and how older lenses were supported. You may have stumbled onto one of those issues.
Mar 20, 2024 15:37:57 #
tcthome wrote:
On my Nikon MC 105 G IF ED 2.8 lens stops down to f-3.2 when at minimum focus distance of 11"so maybe ??? If I back up say to eg., 18-24" it will open up to the f-2.8.
That is also what happens with my Nikon 105 macro, max aperture 'indicated' varies between MFD and Infinity. That is due to Nikons indicating the difference between 'actual' and 'effective' aperture.
But I'm not sure or have not noticed this on any of my non macro lenses.
Mar 20, 2024 15:53:12 #
Rongnongno wrote:
Crop factor.
When using a FX on a DX body, you use only the circle of diffusion center. The camera recognize that and modifies the data as needed.
When using a FX on a DX body, you use only the circle of diffusion center. The camera recognize that and modifies the data as needed.
Really ?!? "Circle of diffusion center" ?!?
Theres no such animal in nature.
That reply is just a jumble of jargon that makes no sense at all for any purpose, seemingly composed by a glitchy AI bot.
Mar 20, 2024 16:03:10 #
Grahame wrote:
Adjust your focus distance and see if there's a difference in indicated max aperture.
There is such an effect with macro lenses at very close focus, but his 50mm f/1.4 and f/2 lenses cannot focus close enuf to invoke that.
Mar 20, 2024 17:31:54 #
User ID wrote:
Really ?!? "Circle of diffusion center" ?!?
Theres no such animal in nature.../...
Theres no such animal in nature.../...
You are right.
A simple correction of my mistake due to my ESL...
Should have been "lens circle of projection".
Mar 20, 2024 19:42:01 #
Bohica
Loc: SE Coast of NC
After contacting Nikon, this is normal due to the DX 1.5 increase inpercieved focal length. The camera thinks I have a 75mm and adjust the f stop accordingly
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