bvanant

I think as you say it is positioning. My go to is to have the strobes pretty far behind the handles of the housing and pointing out at like 20 degrees. Bill

If it works for you then great. I prefer the 90 degree cable connectors and they are hard to use with thicker cables. In terms of cost they are about $6 each in small quantities. Toslink cables I think are about $6.50 on Amazon for a meter and you can make straight connections for very little 4 using heat shrink tubing. A meter of 613 fiber cable is $7.50 (you can of course use them straight not coiled) so the total cable is $20. Not a large difference, basically a single nitrox fill here in LA. Bill

Well I am not sure about the much more light argument, the 3 mm cable has a loss of 0.24 dB per meter and the 613 fiber optic has a loss of 0.4 dB which is the difference between 94 and 91 % transmission if the NA of the two cables is the same. So you get 3% more light from a 3x larger cable. In any case, if it works it works. As for "coiling requires heating the cable, as in hot water, and heating is well known to "cook" the optic fiber, making it opaque and markedly reducing the light transmitted. Both the added cable length and the reduced light may explain why some strobes such as the Sea&Sea are said not to fire consistently with coiled fiber optic cables." this is simply not true at least for the 613 cable fibers. I have tried to measure (with an integrating sphere) the loss of transmission upon cabling and it is hard to see the difference; it is only a few percent. I have never broken even the 1 mm single fiber cables (they are PMMA and if you try to break one by pulling or bending good luck). The biggest advantage to me is that the multi-core fibers can be bent over a 1mm bend radius and still transmit 95% of the light, if you bend a thicker fiber it will stop working. Again if it works for you then don't worry. Bill

I am pretty sure that most FO cable sinks. PMMA has a density of 1.2 or so. If the cable is secure in a given strobe configuration then moving the strobes out will either require unwinding or it will pull the fiber out of the camera or the strobe. I suspect that there is a reason that all of the commercial FO cables are coiled, both for strain relief and for ease of changing lighting configurations. Bill

HUH? I thought the olympus 60 macro was 1:1 i.e. 17 mm wide. Bill

I don't mind the coiling for setup; for me straight FO cables always seem to somehow get in front of the lens or are too short to get the arms out straight (something I rarely do). Certainly they are much cheaper and if you get a large enough diameter fiber you can use the LED triggers and TTL at least on Inon strobes. I have not had good success with straight fibers (although at 1.5 mm diameter) getting reliable TTl from my OMD-EM1 -II and some S&S strobes. The other disadvantages are that if you are at all klutzy (guilty) you can end up getting them crimped and you get a lot less light through and they are hard to fit into the 90 degree fittings. Bill

To get the most magnification you will have to change your lens. The longer the focal length the more magnification you will get from the CMC. The CMC is a higher magnification lens than the CMC-2 and the best way to use the CMC is with the 60 mm macro lens. Bill

That observation is how fiber optics work. If you look at the ESKA fibers for example, their 2 mm fiber has a minimum bend radius (0.5dB) of 80 mm or more than 3 inches. If you look at their 1 mm fiber the minimum bend radius is 25 mm or about an inch. If you look at the 613 core fibers (1 mm fiber diameter) the minimum bend radius is 1 mm, and for the 1.5 mm diameter fiber it is 3 mm. This means that it is easy to coil the multi-core stuff and that if you crimp a large diameter fiber it will stop transmitting. Certainly polishing of the ends (there are better ways than candles) will improve transmission. If you don't want coiled cables then large diameter fiber is fine. If you want them coiled then the multi-core stuff is easier to work with. YMMV Bill

As for the coupler, we have used those in our lab with quite good results. BVA

Not the cable by itself but Tooke sells multi-core cables on Ali quite cheaply. Bill

Second the mention of prescriptiondivemasks in San Diego. We have used them for years Bill

One other possibility is to use the 60 with the 1.4 teleconverter. A bit more magnification (1.4x) but you lose a stop. Very popular with the nudibranchers here in SoCal. Bill

Just to let you know it is missing the two set screws (McMaster Carr) that go in the port groove. If that makes a difference then go ahead with Troporobo Bill

I have one ready to go. They are $240 new, how about $150 Bill

I have one, will check on it and let you know a price. Bill