On 6/16/2016 10:18 AM, SwissPace wrote:
Hi All,
The subject of taking photos of the eye in particular details of the cornea has come up again, what i am looking for
is a quick and easy way for kerstin to take photos to geve her enough detail, I tried with macro lenses on the OM-D
etc.. but its rather fussy and then i wondered if focus stacking using a TG-4 and lightguide might be the answer.
Before I leap to buy though I was wondering if anyone would be willing to try it out for me. recording the detail of
the cornea (apparently it contains a lot of health information to the trained eye) is the goal so the picture taking
needs to be as quick and effortless as possible.
I'll take a shot at this.
It may be trickier than it sounds. I watched a counterperson trying to demonstrate it. The camera focused on the
reflections on the surface, rather than the iris. So a bland/blank background may be easier.
Absent any other subject, as Carol is out and about, I made this a little selfie project. Using the W-fi remote control
app on my phone and holding camera up in front of one eye and phone in front of the other, I tried it.
Light is a problem at such close quarters. The add-on ring light pipe illuminates evenly, but gives a lovely reflection
of itself in the eye. The LED illuminator alone still gives reasonably even light and the reflection is much smaller.
Here's about the best I came up with, full frame and crop.
<http://zone-10.com/tope2/main.php?g2_itemId=20267>
Thoughts and speculations:
I could have set up a tripod, other lights, etc. but as proof of concept, I
think this was sufficient.
Shooting someone else's eye would be easier, with better results, only the LED
reflected, with a little care.
DoF may a problem, if one needs sharp focus all over. I may not have been exactly square to the eye. Though I tried,
juggling the two gadgets to frame and look into the camera while also seeing the phone screen was a bit tricky. The
Focus Stacking option would deal with that, if necessary.
The accessory tele adapter would allow greater magnification while still maintaining enough distance to illuminate it. I
tried a shot with it, but there were too many reflections where I was standing and focus or the low shutter speed made
it softish. I think the aux lens blocked the LED, so I stood where there was more natural light. I know from other work
that it can be quite sharp.
Whadda Think?
Self Eye Moose
--
What if the Hokey Pokey *IS* what it's all about?
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