Focal length with FTZ adapter

420mm is a 1.4x crop factor. I know that the lens zooms in a little due to focus breathing when it's focusing close, maybe Nikon takes the effects of focus breathing in their lens equivalents?

Ravikiran10 said:

Hello -

When I use a Nikon AF-P DX 70-300mm f/4.5-6.3G ED VR lens on a Nikon Z 50 using FTZ ii adapter, the effective focal length of the image taken with focal length of 300mm shows 420mm instead of the expected 450mm (1.5x crop). What could be the possible reason for this?

Note: All firmware versions are up to date.

Any help/suggestions in this regard with be greatly useful.

Thanks in advance.

Click to expand...

Apologies for these questions, but I am not familiar with Nikon bodies.

When you say that the focal length used was 300mm and the equivalent focal length was 420mm, are these the numbers displayed on the camera or on software on your computer? If on the computer, what software were you using?

What does the EXIF data in the image file show for the actual focal?

Try taking a few more shots at different focal lengths to see whether the problem is repeated.

--
Chris R

The possibilities that I can think of are:

• You made a mistake and the shot was actually taken at 280mm.
• The camera made a mistake. Maybe clean all the connections between the body, adapter and lens?
• The computer software used has a bug.

It should show up as 450mm in FF equivalent. Try some more shots. It might be that lens was not fully on 300mm when shot was made. Somewhere in exif it should show both focal lengths to double check to see if lens was indeed at 300mm. If so, I have no idea what could have went wrong. Adding the FTZ will not change the focal length or the crop factor in any way.