Nikon D300 thinks Nikkor-Q 200mm f4 lens is f5.6: Okay I was fooling around with a D300 and a Nikkor-Q 200mm manual f4 lens in aperture priority mode. The camera shows all the f-stops...

DaveC1 Loc: South East US

Okay I was fooling around with a D300 and a Nikkor-Q 200mm manual f4 lens in aperture priority mode. The camera shows all the f-stops off by one stop. So f4 on the lens shows at f5.6 in the camera and f22 shows at f32?

DaveC1 Loc: South East US

Never mind I think I figured it out. Is it because is the D300 crop sensor and the lens is intended for a full frame camera; so as the effective focal length goes up from 200mm to 300mm the f stop must go up by one stop just like with a teleconverter. There is no such thing as a free lunch!

And that probably means that my Nikkor AF 1:1.4 D is effectively a f 2 on a crop sensor camera?

The laws of physics are still in force no matter what some may wish.

DaveC1 Loc: South East US

And does that mean by the same logic that a AF-S Nikkor 55-200mm 1:4-5.6 ED is a f 3.0 - f 4.0 on a full frame camera or is it f 4-5.6 full frame and f 5.6 - 8 on a cropped sensor camera? Just how has Nikon written these specs????????????

wilsondl2 Loc: Lincoln, Nebraska

DaveC1 wrote:

Never mind I think I figured it out. Is it because is the D300 crop sensor and the lens is intended for a full frame camera; so as the effective focal length goes up from 200mm to 300mm the f stop must go up by one stop just like with a teleconverter. There is no such thing as a free lunch!

And that probably means that my Nikkor AF 1:1.4 D is effectively a f 2 on a crop sensor camera?

The laws of physics are still in force no matter what some may wish.

Not so. My FF lenses come up with the same f/stop on crop and FF. I have had lenses that would not go up to the largest aperture for example a f/3.5 lens would only go to f/4 and when put on another camera would go to the f/3.5. First one Nikon D90 other a D7100. - dave

DaveC1 Loc: South East US

wilsondl2 wrote:

Not so. My FF lenses come up with the same f/stop on crop and FF. I have had lenses that would not go up to the largest aperture for example a f/3.5 lens would only go to f/4 and when put on another camera would go to the f/3.5. First one Nikon D90 other a D7100. - dave

So what are you saying; I'm not really clear.

For what its worth my Nikon F4 body seems to think my AF-S Nikkor 18-55 1:3.5-5.6 G lens is an f4.0 at 18mm focal length.

Bill_de Loc: US

DaveC1 wrote:

Okay I was fooling around with a D300 and a Nikkor-Q 200mm manual f4 lens in aperture priority mode. The camera shows all the f-stops off by one stop. So f4 on the lens shows at f5.6 in the camera and f22 shows at f32?

I'm not familiar with the lens, but I think it is old. If it is a non CPU lens you need to go into the menu and enter the focal length and maximum aperture. You will find it in the setup menu

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DaveC1 Loc: South East US

Bill_de wrote:

I'm not familiar with the lens, but I think it is old. If it is a non CPU lens you need to go into the menu and enter the focal length and maximum aperture. You will find it in the setup menu

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Thanks,

rmalarz Loc: Tempe, Arizona

If this lens doesn't "talk" to the camera, you have to tell the camera which lens you are attaching. The menu system should have a non AI setting section. Check for that and put the lens information in the camera. Then, don't forget to tell the camera when you attach the lens.
--Bob

DaveC1 wrote:

Okay I was fooling around with a D300 and a Nikkor-Q 200mm manual f4 lens in aperture priority mode. The camera shows all the f-stops off by one stop. So f4 on the lens shows at f5.6 in the camera and f22 shows at f32?

DaveC1 Loc: South East US

rmalarz wrote:

If this lens doesn't "talk" to the camera, you have to tell the camera which lens you are attaching. The menu system should have a non AI setting section. Check for that and put the lens information in the camera. Then, don't forget to tell the camera when you attach the lens.
--Bob

Got it.