My example is a marine fish in an aquarium, therefor I can fill the frame easily. However, is the image better when not cropped so close? Does the principle apply to any photo - i.e. should space be allowed around any subject?
It depends on the subject. For something that is potentially moving (fish, bird, car etc.) having a space at the front gives it the impression it has somewhere to go.
Alternatively for static subjects (buildings?), having it central can make a better impression.
PS - Welcome to the forum.
Alan
It all depends on your preference and what you want to use it for. The closer version shows more details, if that is what you want. You could go even closer and do a macro of the fish's eye if you wanted. People who are better skilled at macro than I am may be able to offer more information.
My own style is not really conducive to macro so I'm a poor respondent for you to listen to. I like a whole bunch of stuff in the frame, so I often get reminded that my photos shouldn't be so busy. For instance, I'd probably include the whole fish shadow in the frame. (I'd crop off that black triangle lower left though, and clone out some of the fish poo and other debris). But then it probably wouldn't be classified as a true macro.
Welcome, and please do jump into any thread that interests you. Good to have you aboard.
It depends on your intentions. If you want a shot that records how the fish looks, without any artistic intent, then getting in as close as you can is the way to go. The first shot is a good example of this. For a more artistic picture, a little more space would be nice to have, with more space in front of the fish, and less behind. This will give the impression that the fish has just moved into your picture. You can crop the second shot a little to achieve this.
The other alternative is to move in really close and show just a small detail, like the head.
Just play with your picture, to see what different crops produce.
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