'red-eye' wide angle adapters

[John Sandel]

Thanks, Richard. I'll be testing an aspheric add-on soon & want to duplicate your grid for the sake of uniformity. Without measurements, your grid gives but a rough visual indication of linear distortion; I'm sure there's some industry-standard image used to demonstrate same. But your grid is simple & useful all the same.

[Tony Davies-Patrick]

Thanks for setting them up, Richard. Yes, the 16X + Red Eye pics were more of what I was after, with better res and less bending. The curvature will obviously be more than with a .7x anyway, but it is still providing almost double the field of view of the widest setting of a 16X, which is more than my Optex does.

The distortion is still there, and increasing towards the corners along with loss in sharpness. Also, because you are so close to the flat subject, and slightly tilted, this increases any distortion. The further you pull away from the wall, and straighten up, the better it should become.

I will be shooting mainly outdoors, so a lot of the curvature will not be noticed, and when it is, such as when I move in ultra-close, this will add some atmosphere to shots. I'm still worried about the amount of softness towards the corners, but by being careful to keep straight lines away from the edges - which is easy to do outdoors - this should be less of a problem.

I’d really like to see some takes from footage in the real world.

Shots set up on a tripod outdoors would probably give a completely different set of results than a slightly tilted tripod and the flat graph on a wall.
Four short takes such as the following, would be nice to see: One, a wide landscape with no subjects close to the lens (using the 16X alone and then with Red Eye) with at least mid-range aperture, and then one with a similar wide landscape, but this time with a subject, such as a tree, close to minimum focus and off-centre of the frame (again with 16X alone, followed by the same with .5X Red Eye attached).

I’m looking forward to trying it out on a complete array of subjects, including some underwater filming, because that wider field of view could be my savour in many situations. We’ll just have to wait and see!

In the meantime, it’ll be nice to see some more test shots.

[John Sandel]

Tony wrote: "because you are so close to the flat subject, and slightly tilted, this increases any distortion" etc.

Richard, that reminds me, can you say how close your camera was to the wall when you shot your grid? Best guess, from the front of the lens, will do, as you've doubtless struck the setup. Thanks.

[Richard J Morris]

Hi John - I kept the distance from the wall to the closest piece of glass (Red Eye or lens) at the same 675mm, adusting the camera back and forth to suit the effective lens length.

Tony - more outdoor shots are a problem for me - the cameras and lenses are works cameras and we have very tight usage restrictions on our proving ground (confidential prototype vehicles etc). Trying to get them off-site is even worse - no insurance!
If I get chance, I will...... but don't hold your breath!!!

Can anyone else can help out with this one....??

Thanks

[Jon Turner]

i have now bought a red-eye and have some test images. if anyone would like to see them i will email them to you as i have no website. let me know who wants them!

[John Sandel]

Jon, I'd like to see your images, please.

johnsandel@earthlink.net

[Peter Wiley]

I'd like to see them too, and I would be happy to post them to my Web site

[Chris Hurd]

Actually Jon, please send 'em to me and that way DV Info Net can host them for you to everyone's advantage. Thanks in advance,

[Jon Turner]

ok folks, they're on their way to you all. let me know if there's any problems.

i should add that i am using an XL2 and the 0.5x redeye.

[Chris Hurd]

Thanks Jon,

Uploaded to http://www.dvinfo.net/media/redeye/ -- enjoy,

[Richard J Morris]

Thanks to Jon and Chris.

Jon - I notice that even at F11 you are losing sharpness as you move outwards from the centre. I was hoping that was only at the lower F numbers I was playing with......

Has anyone tried a Red Eye 0.5 on a 3x at F16?

[Jon Turner]

there is a note in the instructions that accompany the lens that says 'at f16, everything is in focus, including any dust on the lens!'

[Richard J Morris]

Ahh - a heretic - someone who READS instructions!

Seriously though Jon - you are totally correct. I had not appreciated that there was such a dramatic jump from F11 haziness around the edges to F16 absolutely everything in focus.

I suppose the upshot is that if you need sharp focus with a Red Eye you MUST use F16. Thanks for that Jon.

[Jon Turner]

richard - interestingly, i'm currently shooting at f1.6 and everything is completely in focus! it seems to get more blurred around the edges in the higher Fs. hope to post some more images for you guys in the next couple days, if chris will have them. hopefully with experience my images will improve. the shots already posted are literally the first things i've shot, so i wouldn't jump to conclusions as they're far from rigorous tests

[Jon Turner]

also, even at the lower Fs, everything is in focus. in regard to f16, the instructions (burn the heretic!) say that using ND filters decreases depth of field, but it seems that things get more and more in focus towards the lows of the F range.

should you want to join the heresy, the instructions are (more or less) reprinted at http://www.b-hague.co.uk/Wide_Angle_Lens.htm