Thanks again everyone.
Hi Suzy, this was my first attempt at a forced perspective image and was a bit harder than I expected. The idea is to have the camera well back from both people and fully zoomed in (a technique called lens compression) and also use a high f stop to get both people in focus. I used a 70-200mm on a full frame camera, and wanted to use f32, but unfortunately my back yard is not long enough (and we were moving about too much to close the aperture right down), and ended up shooting at 105mm and f20. I couldn't get both of us in perfect focus in the one shot, so I had to "focus-stack" 2 images, since I was a bit out of focus in the single image. My daughter was about 7m from the Camera, on a step ladder, and I was about 20m, holding a wireless shutter release.
I think I could improve it using a plain uniform background, like a large grass field or at the beach, use the full 200mm and close right down to f32, and change our positions to more like 15m and 30m. I think this will get it in one shot.
I had to do it a couple of times to get the positioning right, so it would be much easier not being in the picture, or use another trick instead - with a Canon 6D I can pair it to my phone and see a live view and hit the shutter remotely, but I didn't get that far before my daughter decided I was "taking fooooorrrrrrreverrrrrrrrr"
and so we just took a few images and lucked out in one of them.
I looked at a couple of youtube videos, and did a google image search of "forced perspective" to get some ideas.
Cheers.
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