First, lay the fish on soft ground or a wet cloth or your wet unhooking mat, with some object beside it to give an idea of scale - perhaps a hook packet, a matchbox or a cigarette packet. A ruler would be even better! Now take your photograph(s), making sure that you capture all these details:
It's probably best to photograph your fish in light shade, so that strong shadows from direct sunlight don't obscure detail. For the same reason, I find it best to avoid flash, because it can bleach out important features like scale numbers. Take the photo from directly above the fish, or from exactly side-on, so that its shape is accurately shown. A head-on shot is often useful, though for this you or someone else will have to hold the fish.
This information should enable you to produce photographs good enough to identify the fish as a crucian carp. Remember that the photographs must be really sharp, so watch out for camera-shake! crucian carp are tough but need to be treated with care and respect, like any fish. They are usually quite considerate and lie still. If you make the procedure as brief as you can, if the fish is lying on something soft and non-abrasive and if you keep it wet and out of the hot sun, then it will come to no harm.
Taking pictures of fish for the purposes of having a nice reminder of a day out or a special capture is not an especially difficult procedure, you simply get out the camera and shoot a few. The result is usually OK, it has the fish in it, sometimes it has you in it with the fish, sometimes its just the fish laid on the grass looking pretty enough on its own. If the picture is for the album, then anything will do, that pleases you.
However, when it comes to identification, or more importantly, record claims, and especially with the capture of a specimen of those species where potential mixed parentage is always going to be a problem that needs to be addressed by experts, then things have to be performed in a more deliberate fashion. There is never going to a problem with a pike or a full grown bream, nor is there any doubt possible with barbel or tench, these fish are clearly what they are, and cannot possibly be mistaken for anything else. However, with certain other fish, the problem is very real and sorting out the truth of the matter will require that the experts, who will scrutinise the claim very carefully indeed, be given as much information as possible concerning the fish in question, in the form of photographs.
From left to right:
• Marsh Farm. Typical trophy shot. Can see mouth, can't count scales, dorsal fin down.
• Marsh Farm. Mat shot. Mouth unclear, dorsal fin down.
• Stockton Reservoir. Bad mat shot with cropped off mouth.
Roach, rudd, silver bream and crucians all fall into this category of fish that may well not be what are claimed to be, all of them cross-breeding with other fish and producing hybrids. The problem with hybrids is that they usually grow faster, live longer and consequently grow larger than the true species they are a mixture of, but often mistaken for. Hence the more numerous false claims than true ones. Roach x bream hybrids obviously have the potential to outgrow roach because bronze bream grow to very large proportions, however, it is true that a hybrid of a roach and a rudd, both fish that grow to a maximum weight of four pounds or so, can grow larger than either parent. With crucians the hybrid question is every bit as important, claims routinely dismissed as a cross with either brown goldfish, or common carp.
What makes life difficult is photographs that are missing vital information. With all the above 'confounded fish,' scale counts, fin ray counts, fin shape, and a number of other important characteristics are what the experts require to be certain about them, for true species display a limited range of possibilities on these scores. Hybrids on the other hand, usually display one or two characteristics that are outside the possible ranges for true species, and will be dismissed out of hand if they display too many of them.
Taking these all-important photographs is a tricky thing. The majority of photographs submitted along with claims are generally very poor material indeed where identification is concerned, the captor putting the job of getting a trophy shot ahead of the more important task of securing clear, unequivocal evidence for the claim they are about to make in the form of a properly arranged, well-focused and well-exposed mat shot. The problem with trophy shots is that the fish usually has its dorsal fin down, the captors fingers often obscure important fin detail, the angle of the shot often makes counting scales problematic, over exposure, especially with flash shots taken at night, burns out detail in reflections, and, scaling the fish against a human body is a very unreliable means of establishing either approximate weight, or measurements.
Mat shots are, on the face of things, relatively easy to make compared to the difficult task of making a half-decent trophy shot. The fish is laid out and the shot taken from above. That's all there is to it. However, securing an accurate mat shot, one that is going to give the experts exactly what they require to do their job, is quite another thing. Here, rules must be obeyed.
The first rule is clarity. Focus must be as sharp as possible and exposure must be correct too. Both of these are easy to achieve in overcast conditions or in the shade, but neither are easy to get on bright sunny days in direct sunlight, and both are a matter of sheer luck at night.
The second rule is scale. The shot must be taken from directly above the fish if possible, the fish laid out in the landing net because the mesh helps tell how far out of vertical the shot is, and a scaling object of known proportion should always be included in the picture.
The third rule is composure. This concerns the fish itself and is to do with getting it well framed and central in the picture with all relevant detail made clear, none cropped off by the frame or obscured in any way. So, fins must be fully extended, which is no easy task, nothing should obscure detail, such as anal fins hidden under folds of mesh, or the mouth, which in the case of crucians carries crucial identification detail concerning the presence or lack of barbules. A separate medium close-up shot of the head of a crucian should always be taken and I would take this shot at a slight angle toward the mouth of the fish because the folds of the lips seen from directly above can easily be confused for barbules or the remnants of them (every single picture I have of a Marsh Farm crucian suffers this illusion) but from an angle, all confusion is removed at once.
From left to right:
• Marsh Farm. Better shot for ID. Can count scales, dorsal fin up, but tail unclear, as is mouth.
• Stockton Reservoir. Typical after dark flash shot. Scales clear but in previous shot they were burned out and uncountable, dorsal fins down, unwanted objects included. Bracketing got me this one acceptable shot.
• Parkers Pool. Lovely picture but scaling is unclear because can't read the float legends. Everything is clear and as it should be, but the caudal fin has the appearance of a non crucian.
The fourth rule is Sod's Law. Take at least three or four shots and never, ever rely upon just the one. You can almost guarantee a bad one if you do...
I run a blog so I take an awful lot of shots so that I always have sufficient material for every post. This means that I not only take trophy shots of the best fish, but three or four mat shots too, and, as a matter of course I also take sufficient mat-shots of lesser, but nevertheless interesting fish, for illustration purposes. I also study silver bream so whenever a fish of this species is caught, I will flip the fish and take pictures of it from both sides because lateral line scale counts often vary, side to side, by a single scale. With crucians, who often have irregularly spaced and irregularly sized scales, I think this would also be good practice and especially so with any fish missing a scale, or series of scales, along the lateral line.
My procedure with a good fish is to unhook it first, then take my mat shots, weigh it, and then put the fish either in a keep-net or rest it in the water in the landing net. I'll then set up the camera in readiness for the trophy shot at my leisure, knowing that the fish is safe and well, the entire first part of the procedure taking no more than a minute to accomplish if everything is made ready in advance. You do get a lively fish by this way, and that's a problem in its own right, but it's better than having a needlessly distressed fish out of its natural element for far too long, otherwise.
My mat-shots almost always include a scaling object. Nowadays that is usually my brass Salter spring balance because it is a known length, and looks good alongside any of the smaller species. For larger species it'll be a centre pin reel, even if I actually used a fixed spool to catch it (the variable spool extension is unreliable for scaling purposes) and for the same reasons. For some fish I'll use a float. This is OK with unimportant fish where its size is not an issue, lending the picture a sense of proportion and pleasing aesthetics, but for important fish I'll always use either the spring balance or the reel because they are known quantities with fixed dimensions, whereas floats, if their make and shotting capacities are not shown in the picture, really could be any size at all.
Handling the fish in preparation for a picture is a relatively simple matter made complicated by the wrong procedure. The best way I have found is to lay the fish in the wet net on deep soft grass well away from the waters edge, and then cover it completely with a fold of the wet mesh to keep it calm. When the camera is ready, the fish is lifted from the fold of mesh and laid back down again. Of course this is complicated by the fish flipping about on the ground and care must be taken here to calm it down by repeating the procedure until it's just so. Covering the fish more or less ensures it is safe and calm, picking the fish up and putting it back down ensures that fins will not be obscured by the folds of mesh and laying it out in the landing net means that a fish that flips about can be easily contained by lifting the frame of the net to stop it from flipping onto hard, damaging surfaces nearby, whilst taking it away from the water's edge means it cannot flip back in before it's photographed and weighed, which would defeat the whole object in one fell swoop!
Of course, there are times when deep soft grass is not available and an unhooking mat will have to be used, and some fisheries insist upon this anyhow. If I can avoid using one, I will, but if I have no choice but use one, then I'll still lay the fish in the net in any case, as the wet meshes break up the bland, uninteresting surface of the mat, and lends texture to the picture as well as a sense of proportion and scale.
Whatever the procedure you take, the shot should be somewhat over-framed rather than under-framed. Include plenty of space all around the fish that can be cropped away later in Photoshop. There is nothing worse than a fish framed with its tail cut off. Also, take the picture with the fish at a well-judged diagonal to the frame and the composition will usually benefit.
Getting exposure correct is often a problem. Modern automatic cameras are best left in auto mode for this because they are quite capable of making a fist of an average exposure in most cases. The job is made easier for any camera, by taking the shot in ambient light and avoiding strong light, so shade on sunny days or overcast conditions are what you want. Low light is a problem though. Dawn and dusk are times when the human brain adjusts easily to lack of light but cameras see these low light conditions for what they are and try to adjust accordingly by firing off the flashgun in compensation. This is hardly ever a good thing, because flashlight and fish scales make a very poor combination.
If I catch a fish at these times, and must take pictures immediately, then I'll take shots at a greater distance from the fish than I would in daylight hours. Actually, I'll bracket the shots and take them from all distances hoping that at least one comes out OK. I have never found a way to ensure that night shots will be good ones with automatic cameras, it must be said, and the results are always unpredictable. Increasing your chances by taking plenty of shots is the best way I know of. I'll take up to ten if things are going badly.
From Left to right:
• Parkers Pool. Group shot of the net of fish. The fish with the odd caudal fin is amongst them and is clearly a crucian with a split fin rather than a hybrid.
• Packington Fisheries. Good shot of a small fish with everything clear.
• Packington Fisheries. Nice shot but no scaling object included. Not a problem with what is clearly a small fish, but a real problem with a very big one.
Focus is rarely a problem with mat-shots taken on auto because all of the subject matter is more or less on the same plane. I trust my camera to make a good job of it, and it almost always does. Nevertheless, taking three or four shots from various distances, but never too close, always seems to get me one or two that are very sharp and clear. At night, with flash, same rules apply as with exposure. Bracket in quantity.
Lastly is the job, which is especially important with crucians, of getting that dorsal fin up. This is easy. Just make sure, that if it won't go up and stay up of its own accord, that you get your fingers in the shot to keep it upm which does ruin the picture aesthetically. But the experts won't care very much about that when they are appraising its outline, as the evidence it provides might allow them to pronounce the fish a new British crucian record and you its captor!