johnec Loc: Lancaster county, PA

If I mount a DX lens on a Full Frame body (Nikon Z7ii with FTZ adapter) does the angle of view of the lens change from what it was on an APS-C body, or is the angle of view only dependent on the lens, regardless of the sensor?

BebuLamar

The angle of view depends on both the lens and the sensor size. However, if you mount a DX lens on a FF camera depend on which lens you may have a wider angle of view or you may get about the same angle of view as a DX camera with the outer part of the frame dark. Most DX lenses would give you slightly wider angle of view.

User ID

That info is the general facts.

But specific to your Z camera you can ignore it. The Z will sense that a DX lens is mounted and will convert itself to DX format. So the DX lens does exactly the same job it did as when it was formerly mounted on a DX camera. IOW, theres nothing to convert or translate.

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The above refers to coupled lenses. A fully manual noncoupled lens that is designed for DX sized sensors will not trigger the camera to convert to DX. If you use such a lens, THEN BebuLamars explanation will indeed be in effect.

BTW, the automatic conversion to DX cannot be disabled. This is sometimes unfortunate cuz some DX lenses have unused coverage outside the DX format (just as BebuLamar described).

The automatic conversion to DX reduces your pixel count by about half. IOW its just cropping an FX format down to DX. Your Z7 will use about 20MP, which still allows further cropping in PP if needed.

CHG_CANON Loc: the Windy City

The focal length of a cropped sensor lens is what the lens says: 50mm DX is the same 50mm FX. The field of view difference is the crop factor of the sensor. The 50mm DX lenses focuses a smaller circle of light onto the smaller DX-sized sensor. When that DX lens is mounted to a full-frame camera, that same smaller circle appears on the larger sensor, causing some amount of shadow around the edges of the image. What is focused is still via a 50mm lens, it just shows less of the total scene than an FX 50mm lens, giving a different field of view due to "less" of the possible image being hidden in the shadow / cropped away, as if a longer focal length lens had actually been used.

If you compare two images of the same DX lens on two bodies, an DX and FX, you'll see the same image / same angle of view for the image details that appear in both images. Just overlay the DX image to the FX image; they'll align exactly. If you compare the same focal length for a DX lens on DX and an FX lens on FX, again the 'common' aspects within the two images should be the same, there's just 'more' of the scene in the FX version that were cropped away in the DX image, more 'field' of view. The quality of the lenses being compared might cause subtle differences, including possible differences in being exactly the same focal length in millimeters.

johnec Loc: Lancaster county, PA

Thanks to each of you for the explanations. They are very helpful. As I began to dig into this a little more deeply I came across the following website, which clarifies and muddies at the same time. https://shuttermuse.com/angle-of-view-vs-field-of-view-fov-aov/

I guess I have more digging to do. One thing is certain: photography and cameras aren't boring :-)

BebuLamar

Angle of view is an Angle. Field of View is the size of the view at certain distance.

srg

You mean you don't have to worry about forgetting to vignette?

Timmers Loc: San Antonio Texas.

All of the answers given are correct and accurate to varying degrees of correctness. If that is all you need and want, be on your marry way happy in the non-creative understanding of the optic as a tool. Here is the more creative understanding of the question.

The first thing that you need to understand about an optic's ANGLE OF VIEW is that it has some rather interesting facts. First, the optic, all optics have a center point (you see this in camera viewing systems represented as that tiny circle in the dead center. Everything that lies on that spot is flat. It has no dimension and never will have any dimension regardless of focal length. In the 'regular' optic application this has absolutely little interest, because you don't move the lens.

Another critical point is that a lens can have an angle of view (this has several names) and if you can not move the mounted lens then this has little effects. This is power of a view camera lens, the front standard can move and place that optical center in different locations of the field of view.

For fixed body camera lenses there are odd ducks, the so called lens for perspective correction. Here the lens can shift where that optical center is placed. When you move the optical center point you are moving that flat point of the lens, the thing that controls perspective. This is possible because the lens has a great than normal application of the fixed center point of perspective due to the greater field of view.

This then is the rub, by moving that center point of perspective you are taking creative control of the scene. In effect you are altering the viewer's training that all lenses take pictures with the optical center at the dead center. This is NOT the same thing as just re-cropping an photograph, but, yes, it is a mild version of why some crop a photograph.

The important thing is that you can learn to use a PC lens so that you are shifting the optical center from the 'normal' center location. Truth is you can just think your way through this but need to get hold of a PC lens, shift and rotate the lens and the begin working with the lens in this state. Remember, YOU have been trained to see the optical center in the center with billions of images that you have seen, and to find this alerted way of seeing you must actually go make images with this type of lens. It will be an eye opening experience. Of course you could just learn to use a viw camera, there the options become unbelievable!

fetzler Loc: North West PA

Lenses have two basic properties focal length and the diameter of the image circle. FF lenses have a larger image circle than APS-C lenses. The angle of view is determined by both focal length and the sensor size.

Consider an 8 x10in view camera. A 300 mm lens is a normal lens on this camera. It has a similar angle of view to a 50mm lens on a FF camera.

Consider an exposure is made on 8 x 10 in film. One could then cut the negative to 4 x 5in taking the central portion of the image. One could then take the central portion of the 4 x 5" negative to make a 2 1/4 x 3 1/4 in negative. Clearly, the angle of view on the negative will depend on the size of the negative. Remember, the camera and lens for each negative is the same. Furthermore, the focus point on each negative is the same.

ecurb Loc: Metro Chicago Area

[quote=User ID]That info is the general facts.

BTW, the automatic conversion to DX cannot be disabled. This is sometimes unfortunate cuz some DX lenses have unused coverage outside the DX format (just as BebuLamar described).

This is not necessarily true. I shoot a D600 and it has a setting to turn off automatic conversion to DX format when a DX lens is mounted to the camera. I have not bothered to research this with newer cameras, I just assumed Nikon would keep the feature on the menu.

User ID

What I posted is 100% fact. (Try reading more slowly, perhaps aloud.) Yes, newer cameras do differ from yours. I use old and new, so I dont need to research or assume anything.

Your SLR is outside the discussion. FWIW, unlike a Z camera old models DO permit disabling automatic DX conversion. But, that doesnt apply to the OP.

SuperflyTNT Loc: Manassas VA

Well this seems totally unrelated.

SuperflyTNT Loc: Manassas VA

In general, while it’s pretty simple when using a FF lens on a crop camera, the AOV is dictated by the sensor size, when using a crop lens on a FF sensor it’s more complicated. As has been stated the other component that comes into play is the size of the image circle. Crop lenses can be smaller and cheaper because they don’t need as large of an image circle, but some crop lenses still have an image circle big enough to cover a FF sensor. Especially with zooms. The size of the circle changes as you zoom and you might get full coverage at one end and vignetting at the other. At the very least you should always be able to get a square image the height of the FF sensor. As has also been stated, with the Z cameras all this is moot since it automatically switches to DX mode with no ability to override.