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ignatiusjk
31-Mar-2011, 19:27
How will a picture look if I shoot a scene from a distancee with a 300mm lens or get right on top of the shot with a 90mm lens? If I'm in Yosemite shooting Yosemite Falls would the picture look different if I get right up to the falls or shoot it from a distance with a longer focal lenth lens. Keep it simple.

Leigh
31-Mar-2011, 19:38
Yes, they would look different. (that's simple)

Shoot both and compare.

- Leigh

ignatiusjk
31-Mar-2011, 19:42
I'll be in Yosemite in early June and plan to try it.

Brian Ellis
31-Mar-2011, 22:44
Sure they'll look different. By changing your camera position you'll change the perspective.

Vaughn
31-Mar-2011, 23:34
The closer you are to something, the bigger it looks relative to something farther away (both to our eyes and how it ends up on the GG).

With this in mind, imagine you are taking a photo of Yosemite Falls and have the whole Falls in the image -- top of the Falls at one edge of the negative and the bottom of the Falls at the the other edge.

If you are using the 90mm lens, you would have to be much closer to the Falls to frame the shot as described above than if you were using the 300mm lens. So being close to the bottom of the Falls, the top of the falls are much further way from you than the bottom of the Falls...thus the bottom of the Falls would be much bigger on the GG than the top of the Falls.

With the 300mm lens, you would be standing much further away from the falls to get the whole Falls in the photo. Compared to where you had to stand with the 90mm lens, the bottom and the top of the Falls are both far away and are relatively the same size on the GG.

If you replaced Yosemite Falls with a tall building, you can see why when taking a photo at ground level close to the building, the base of the building is closer and looks much bigger than the top of the building, which is much farther away from the camera. On the GG, the sides of the building appear to slope inwards as the building appears to shrink as it gets farther away from the camera.

Stand fall enough back with a long enough lens, the bottom and the top of the building are about the same distance from the camera, and are about the same size on the GG -- the sides of the building will have very little tilt inwards.

That's perspective in a nutshell. Of course other things change, too. The relationship between the foreground and the Falls will change as you move closer...trees in the foreground become bigger relative to the Falls. And in reality, I do not believe there is a vantage point where you can fill the frame with Yosemite Falls with a 90mm lens on a 4x5.

Vaughn

PS -- I did not go into how one uses back tilt to "correct" for this change in perspective.

Looking at the GG and moving the lens away from the GG, you will notice how the image gets larger on the GG. So with that in mind and using the building as an example, imagine having your camera pointed upwards to get the whole building in. As you tilt the back of the camera forward, the top of the back gets closer to the lens and the image on the GG there (the base of the building) gets smaller. At the same time, the bottom of the back is moving away from the lens and the image on the GG there (the top of the building) get bigger. Thus you can in theory, make the bottom and the top of the building the same size and not get the sides of the building sloping inwards.

The simpler way to do this if you have enough front rise, it to keep the camera level and use front rise to lift the lens up until you have the building all in the shot. It is the same idea -- the distance from the top of the GG to the lens is smaller than the distance from the bottom of the GG to the lens.