Macro lighting techniques

[Smokedaddy]

So I have my indoor stationary horizontal rig (meaning not mobile) in mockup mode and testing to see how everything works. I haven't done a lot of macro stuff in the last year as I've been focusing on my microscope setup exclusively. At the moment I am using a Canon 50D and a MP-E on my rig and will stick with that lens and a couple of reversed enlarger lenses for a while. I have a pair of Jansjo lights, a pair of Trond LED's and Fostec fiber optics lights. I don't use a flash yet and haven't purchased any external remote flashes since I am not savvy on what to buy or their usage. My setup seems to be aligned properly and stout. The problem I need help with is non-flash lighting and trying to eliminate the specular reflections or diffused reflections as much as possible?

Here are a couple of test examples. I wasn't interested in the actual stacking output that much, more on the lighting. The first isn't that great of a subject since it has deteriorated a lot but serves the purpose. I am extremely unhappy with the second image, which is a Saratov meteorite. I tried holding a large circular polarizer (from my Pentax 6x7) in front of my MP-E but hot spots from the physical lights were there and naturally the image was much darker. I tried tissue, styrofoam, etc. in front of the lights as a diffuser too. Just looking for some sort of direction.

Edited: The image stack was just eye-balled for steps and I could of done a few additional shots. My concern is lighting.

[zzffnn]

Member Johan summarized his experience with many diffusion materials in his web page: http://extreme-macro.co.uk/macro-diffusers/

Their effect seem to vary quite a bit. Have you tried stacking sheets of Vellum Paper? Amazon US sells it for cheap.

[rjlittlefield]

I tried tissue, styrofoam, etc. in front of the lights as a diffuser too.

Those words in front of the lights are a red flag.

The diffusers need to be positioned very close to the subject and wrapping around it, so that from the standpoint of the subject the diffusers sort of "fill the whole sky".

To eliminate very bright reflections from shiny subjects like your meteorite,you want the light to be coming from all directions with nearly equal intensity. That way whatever bit of environment is reflected by each facet will be almost equally bright. What you're seeing now are reflections of light sources that are very small and very bright compared to the rest of the environment.

--Rik

[Smokedaddy]

Member Johan summarized his experience with many diffusion materials in his web page: http://extreme-macro.co.uk/macro-diffusers/

Their effect seem to vary quite a bit. Have you tried stacking sheets of Vellum Paper? Amazon US sells it for cheap.

Thanks, haven't read the link yet but I will. I have lots of grades of Vellum since I draw a lot. Never thought of that.

-JW:

[Smokedaddy]

I tried tissue, styrofoam, etc. in front of the lights as a diffuser too.

The diffusers need to be positioned very close to the subject and wrapping around it, so that from the standpoint of the subject the diffusers sort of "fill the whole sky".
--Rik

Thanks Rik, so something like a integrating sphere?

-JW:

[rjlittlefield]

Thanks Rik, so something like a integrating sphere?

Yes. The earliest solutions involved half of a hollow sphere -- pingpong ball, or whiffle ball, or plastic tree ornament cut in half and painted white -- with the subject sitting at its center. See http://www.photomacrography.net/forum/v ... 005#175005 for a more extreme example. I typically use something simpler and more ad hoc, constructed from tissue paper or styrofoam. My wastebaskets are often littered with used Kleenex and pieces of foam cups with blue tape stuck to them.

--Rik

[mawyatt]

JW,

I've had good luck with the various light tents sold on eBay. The small ones are pretty cheap ($20 or less). I've even used 2 tents one small one inside a larger one to get better diffusion and very uniform subject lighting.

You need more illumination power though, studio type strobes work well here, and the flash type illumination helps with vibration because of the very short exposure. One I've had some recent success with is the Adorama SK300II, which is 300WS (typical speed lights are 50~80WS), and has reasonably fast output (1/800 to 1/2000 second), with built-in RF trigger and power control. These have an output max variation of 2%, which is important for stacking. For $120 they are a bargain IMO.

Best,

Mike

[Smokedaddy]

Thanks Rik, now I understand.

-JW:

[zzffnn]

Rik caught the most important point. Sorry, I missed it. Yes, diffusion material has to be close to subject (it needs to look like cloudy sky, from subject's eyes).

Simply fold office paper into a small cone, then put lens/subject inside the cone and lights outside the cone. You should be able to see improvements right away. A ball made of good diffusion material should work even better.

[Smokedaddy]

JW,

One I've had some recent success with is the Adorama SK300II, which is 300WS (typical speed lights are 50~80WS) ...
Best,

Mike

Mike are you using 2 remotes? Do you have a pic of your setup?

-JW: