We handle fish almost daily as either instructor, trip host, or fishing photographer. In all of these situations we want to capture the image and at the same time be sure that we are releasing a healthy fish that is not stressed or exhausted. Insuring the survival of the fish always takes priority over the photograph and there have been many times when we quickly released the fish without the photograph.
Sometimes we have to consider our own safety. Toothy fish like barracuda and sharks come to mind and even a small Jack Crevalle can give a nasty wound if handled improperly. Heck, we can get a sore hand by getting poked with the dorsal fin of a harmless panfish! These potentially hazardous situations can result from getting our hands too close to a mouthful of teeth (as in barracuda), or coming in contact with a sharp spine or gill plate (jack or snook), or an actual intended bite (shark). Cathy once grabbed a decaying sockeye salmon for a photo in Alaska and got her fingers inside its mouth of teeth. It took a month of antibiotics to get rid of the infection caused by bacteria in the rotting process. Be careful where you put your hands. Consider using a boca grip on a big fish to safely handle it for a photograph.
This is the system we use when we photograph fish. The longer a fish is out of the water the better the odds are of it not surviving. If the fish is in good shape one of us will compose the photo while the other is holding the fish safely underwater either gently cradling it or using a net. The person in charge of the fish can be getting it into the correct position for the photograph before lifting it when the photographer gives the word. If the head of the fish is gently cradled in one hand while gripping just ahead of the tail with the other hand, you’ll see plenty of the fish in the photograph and have a comfortable hold on it. For big or especially slippery fish a fishing glove or even a sun glove will help grip the tail. Make sure the glove is wet to protect the fish.
Our first photo will be a test shot of the angler holding the fish in the water. Then we'll check the photo for proper composition, lighting, etc. We may need to do this a couple times. When everything looks good, we'll let the angler know we're ready and on a count of three, the fish is lifted out of the water, the angler smiles, and the photographer fires three quick shots and the fish goes back underwater. We may repeat this process a couple times but with each “lift” the fish is only out of the water for about 5 seconds.
We cringe when we see an angler with a fish out of the water flopping around on the side of the river
while he gets his camera out of his pocket, turns it on, checks the program, and finally gets around to trying to hold the fish with one hand and photograph with the other. The only thing worse might be having the fish fall our of your hands in the boat or it landing in the dirt and stones alongside the water from an angler in a standing position. We always try to keep the net close by and the fish close to the water. If he slips away from us unharmed, so be it.
If the images look good in the preview, it’s time to release the fish. We’re still holding the fish with a firm grip just ahead of the tail keeping it in an upright position in the water. If it’s not anxious to go we slowly move it in a figure-eight or circular motion facing into the current making the gills work. Make sure the fish is in clean water where turtle grass, moss, sand, or mud won't foul the gills. If it's a trout, the water should be cold as well as clean. In saltwater, if the fish is exhausted or bleeding there may be predator fish in the area waiting for a chance to get at him. If it starts to turn sideways or goes upside down it’s in trouble, rescue it and repeat the revival process.
Remember, making sure the fish is healthy and not in any danger is the most important factor.
A few years back we were floating the Limay River in Patagonia and not having much luck. The water was a perfect level with good clarity and temperature, but for three hours we had not put a fish in the boat. Our guide, Nico, opened up his fly box and pulled out a fly he called the Ug. We knew the fly by another name although we had never fished it. One look at the fly and you realize how simple it is, a lot of rubber legs, a chenille body and weighted. Well, it saved our day then and it has many times since that day on the Limay. The Ug has produced some extraordinary fish here on Fishing Creek as well as other trout waters throughout the world. 
Thinking about baby tarpon, snook, jacks, maybe big tarpon? Holbox has it all, with an interesting fishing program to match. Start at sun up each day and fish until mid-afternoon. Come back to the lodge, relax, rest, enjoy hors d'oeuvres, and walk into town for dinner. 
