A question about hoods and lenses came up in another thread, and instead of taking that particular thread more off topic, I decided to start a new thread for this discussion. (See: http://forum.getdpi.com/forum/showth...630#post343630)
In that thread, Jurgen asked,
My goal was to create the worst possible scenario for a hood over a wide lens on a tech cam. To accomplish this I shifted to the very corner of the 40's IC. This required 10mm R shift and 15mm Rise, and was confirmed by the very upper RH corner being clipped black from loss of IC. Next I positioned the Sun just outside the frame at top center. It was Noon, so in order to achieve that positioning, I needed to angle the camera up about 20 degrees in addition to the already added rise. The exposure is about 1/3 stop below having a clipped blue channel in the sky -- I think it was 1/60th at f8 at ISO 35. I then took a few frames and adjusted the hood so the top and RH edges just showed in the frame. Of course I could have adjusted it so the edges did not show, but my goal is to show that this hood can be adjusted finely enough to just shade the extreme margins of the frame.
Here is that frame. Obviously the image is only for demonstration, not art, so it has not been corrected at all, including no LCC:
I have inspected this frame thoroughly and there is no evidence of flare anywhere in it.
Here is the uncorrected LCC, captured by placing the LCC panel directly in front of the hood as it was for the above capture. You can easily see the hood margins as well as the lens falloff approaching max in the very corner:
Note that because it's pointing directly at the Sun, I had to UNDER expose the LCC by 2 stops to get a decent histo where we usually have to OVER expose by 2 for the LCC.
Here is the set-up on the camera:
From front, and no I did not blow the dust off before shooting!:
In conclusion, I would have to say this hood works (remarkably) well, at least for the 40HR-w and longer lenses. I realize some photographers may have more dextrous hands than I do and can probably form and them well enough and hold them accurately enough to get away without a hood. But unfortunately I am not one of them, so Rod you are not getting this hood back, send me a bill!
PS: Note that if needed I could make a slat out of black card stock to fit in the filter slots on the hood, insert it from camera left and effectively flag off the LH edge of this frame too. If I made it "L" shaped at the proper aspect ratio to convert the hood from square to 4:3, I could probably flag right to the limits at all 4 edges...