How to take lens profile photo to be suitable for AnglerFish.
If your fisheye lens is not on this list, you can easily take a photo, which can be used to complete a profile. Read how to do it:
- Place the camera on a tripod and head down the lens, trying to set the axis of the lens perfectly vertical. This is very important, read here, how to do it. Distance from the front of the lens to the floor should be about 50-55cm.
- Set the lowest ISO, on 4/3, micro 4/3 and camaras with DX sensor, set aperture to 8-11, on full-frame body 16-22 should be better. Switch the camera to manual focus and adjust the distance on the lens scale to "almost infinity" (closer to the thickness of the lines / dots on the scale). For a given aperture, depth of field is very large, that it should be ok. The point is that the profile obtained in this position ("almost infinity") will be the most versatile and accurate enough for most typical images.
- Place the tape measure on the floor to run from the centre of the frame towards the corner. Don't run the tape towards a window or other light source, to avoid light reflections.
The beginning of the tape does not have to match the frame centre exactly. Example shown in above picture is ok. It is even better, when image centre falls somewhere on the tape surface. The tape does not need also to run perfectly towards the corner. Above example is ok. Length of the tape should be 2m or more. There is no tape very close to the corner, but it is not needed - that area is cut off in defishing time.
- Take the photo.
The numbers on the tape, (near the corner of the picture), do not have to be readable. If watching the enlarged picture on a computer screen, you are able to recognize places, where are the numbers on the tape, it is ok, such a picture is quite usable. If not try to take another photo, with lens set to different distance, or get another tape, with bigger markings :)
- If your fish-eye lens is a zoom, take the photos for the extreme focal lengths and for several (6-8) intermediate values. Actually, arrange all for the shortest focal length, then take one photo after another, changing focal distance each time.
- Send the picture(pictures), with the make/full name of the lens and the camera, to firstname.lastname@example.org (only jpg straight from the camera).
Everything above is about full frame (diagonal) fisheye lenses. There are also circular lenses, giving picture in form of a circle, placed in the centre of the frame. In this case it is hard to determine, how far the measurement should reach from the center. I think that the distance longer four times, than distance lens-floor, should be enoung. So, when lens is 50-55cm above the floor, you should use tape measure of about 2m (or longer, if you have any).
If you have wide angle, rectilinear lens, and you want to make a profile photo for it, follow above steps, byt with two exceptions:
- Extend your tripod to maximum height (1.5 to 2m or more will be ok).
- Important: Place the tape measure to run from image centre towards the corner, but in this case it should run out of the image via the corner.
And one more thing: before the whole action, please contact me, because maybe I am already waiting for someone else to send me pictures from the same make of the lens:)
Thanks in advance :)