mmcgavin

Thanks to all who responded with suggestions regarding the use of off-the-camera flash in autopsy room photography. There were many suggestions but for this type of photography, the whole camera and flash unit has to be compact and essentially consist of the camera, flash bracket and an off-the-camera flash. It is necessary for the off-the-camera flash unit to be the main or key light, providing the modeling lighting and the bulk of the illumination and that the built in flash on the camera provide the fill light. Lighting does need to produce modeling to reveal the contours and textures of the surface and one that mimics the standard portrait lighting works quite well. For this the main light is from the left and above and the fill light along the cameras axis with a ratio of approximately 1.5: 1 or 2:1.

For close-up photography (up to 2x3 inch field) the flash unit mounted on the flash bracket to the side works very well but as the field of view becomes larger the flash has to be removed from the bracket and hand held in order to cast shadows to record modeling. Ring lights which produce no shadows or modeling are contraindicated except for very small fields e.g. 2x3 inch and smaller for a 35mm camera where the working distance (lens-subject distance) is so small.
Thus the optimal would be a camera which would support off-the-camera flash, use the built in flash of the camera as a fill light and be able to dial in the ratio of the main to fill light into the camera. Was it Pentax that had something like this 20 years ago?
I have looked at the different models of Canon and Nikon and see that some of them, including my Nikon D50, have the flash shoe on top of the cover for the built-in flash and thus it is impossible to use both the off-the-camera flash and the built-in flash simultaneously. The question is-"with which Canon and Nikon cameras is it possible to use both the off the camera flash and the built in camera flash simultaneously.”
I have enclosed a photograph of an operator using an off-the-camera flash (without any fill flash from the camera’s flash) to photograph and isolated organ and two photographs-cirrhosis and a nasal tumor. This type of photography is done far better under studio type lighting but there are occasions when speed is of the essence or the subject is too large. The photograph of the operator shows why the whole unit must be compact. This arrangement works very well except, when the flash unit is remounted on the flash bracket, excess synchronizer cable which can drop down and be contaminated by a specimen.
I realize that it is unlikely that any of the cameras offer the option for them to control the main to fill light ratio. However if there are some cameras which accept two flashes, it may be possible to control this ratio by altering the power output of the off-the-camera flash. I presume that none of the cameras offer any control over the output of the built-in flash. A major problem seems to be that the output of the off-the-camera flash is not powerful enough to produce a main to fill light ratio of 3:1 when it is held 4-5 feet off the camera and the camera and its flash are only a couple of feet from the specimen.
I would appreciate any suggestions that could help in this matter.
Donald McGavin

Apaflo Loc: Anchorage, Alaska

How about I carve up your article so that each distinct problem can be addressed without excessive confusion!

First, this article refers to a previous thread at http://www.uglyhedgehog.com/t-398765-1.html
and reading the entire previous thread is necessary to understand what is said here.

Okay there are physically two problems. One solution works for relatively closeup work (1:1 down to 1:2 or so magnification) but a distinctly separate physical solution is needed for shots (such as the one shown in your second image) that have less magnification.

The field of view is the problem, and lighting a small area of say 4" or smaller can easily be done with flash units mounted to the camera, but a shot like the one in your example photograph won't be able to light up the subject texture unless the flash is, as shown, a significant distance to the side of the camera.

This is a distinctly different issue (or non-issue). As far as I know virtually all current Nikon cameras will easily accomplish this. Your camera is a bit long of tooth, but it will also accomplish this easily. Look up "flash compensation" in the User Manual (download a PDF version from the the NikonUSA website).

With a little bit in trickery, using ether optical or radio triggering, any of them will work.

Do not use a sync cable. Either an optical trigger (which might be built into the flash unit) or a radio trigger will eliminate this and other problems.

A radio trigger, if it is mounted on the hotshoe, would have the same problem of blocking the builtin flash. However it can be mounted elsewhere and connected to the X-Sync connector with a short cable rather than the hotshoe. For this work it appears that an optical trigger would be preferred though.

All of them can use multiple flash units at the same time. All of them can easily control the output of the built in flash, in more than one way too. They can be set to fully automatic exposure. They can be set to fully manual exposure. They can be set for compensation, at a set level below the exposure provided by other light.

That is only true because of the way you have optioned the on camera flash. If it were set, as an example, at 1/16th full power, then the off camera flash can easily over power it by multiple times.

All that said, lets think about an overall solution rather than a piece meal approach to each perceived problem. First, for serious work you need a seriously more recent camera. Because high resolution is potentially a requirement, I would suggest a D7200. Match that with any decent 105mm f/2.8 macro lens and both 1.4x and 2.0x teleconverters.

Then get a good solid tripod that is sturdy enough to hold the camera but also will hold one or even two flash units on extension arms. You don't need an RRS or Gitzo tripod (though it wouldn't hurt), but you don't want anything with a 10 lb load rating either.

Continue to use the builtin on camera flash if you like, but one of those twin head macro flash units would be extremely nice. Then, if your current off camera flash does not have an optical trigger, either buy a trigger ($10) or get a different flash. Go to eBay and search through the "Cameras and Photo" section for various brackets. You'll probably find something that works well for almost anything, but really there is no need for a one size fits all approach. If you end up with three different flash units, two tripods, and 6 different kinds of brackets... all that means is life gets very easy, and perhaps more fun too.

And consider the tripod as a third arm. Sometimes you'll be best to mount the entire rig, camera flash and all, on the tripod. Other times you might want the tripod to hold only the flash while you hold the camera. And if you get a radio trigger for the shutter release, you might want the camera on the tripod while you move the flash around by hand. There is no end of what can be done, and given that shooting 10 shots instead of just 1 probably means you are 10 times more likely to get what is needed, experimentation is almost essential.

To get ideas for these things you might browse the macro setup descriptions in the True Macro section at http://www.uglyhedgehog.com/t-32754-1.html. Ninety percent of what you see won't apply to your situation at all, but the few that do might be very useful!

Now, all that said, a word of caution. It will not do a bit of good to try to respond to this entire article all at once in one reply. Instead, pick out one specific thing and ask about that in one article. Narrow it down to avoid the confusion. Get a complete answer that is fully understood before you move to the next issue. You may end up having to put each individual issue into a separate thread (UHH is full of all kinds of opinions, and if anything goes viral... the thread is done!)

BHC Loc: Strawberry Valley, JF, USA

Check out the Lepp Flash Bracket which permits the use of two outboard flashes and is highly adjustable.

http://www.ebay.com/itm/Professional-Photography-Deluxe-Macro-Flash-Bracket-Strobofram-Lepp-/302032958326?hash=item4652913376:g:xLUAAOSwT5tWMHjx

Apaflo Loc: Anchorage, Alaska

That would be a very nice, and more flexible, alternative to the twin flash units designed for macro. The existing off camera flash unit, plus a second one like it, could be mounted on that unit, with optical triggers, and accomplish everything the twin macro flash does.

Along the same lines, using eBay to search for "Follow Focus" components, might produce ideas for a custom design that could have advantages. Sturdy, and with longer arms to hold a flash farther away from the camera? There's just no end of ideas... Look up Manfrotto 196B-2 articulating arm, or the Manfrotto 237HD flex arm. Various methods can be put together than are adjustable from what will work well for macro to something that will also work at much larger sized images.