Parrotfish and Deep Focus

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Saturday dawned brilliant and promising. I was looking forward to going back to The Eel Garden near Pig Island  to find the Leafy Sea Dragon which has been reported to be on the old catamaran. I looked in vain for it last week, but a fellow diver, Hendirck, told me that he had found something promising. In return for the information, I dragged out my old Canon G10 and its underwater housing for him to try out.

Unfortunately, with all of the juggling around of cameras, housings and memory cards, I managed to show up at Magic Passage for our first dive with my G11 showing “NO MEMORY CARD”. Ai ya yai ya yai!  Stupido!  So, I did a very nice dive on which some very interesting critters were spotted, but I had no camera.

Never mind. I pretended to enjoy it, playing Divemaster and pointing out all sorts of fascinating items which I determined to burn into my brain memory cells instead of my usual memory contained in my camera. The camera is much  more reliable.

On the second dive at The Eel Garden, Rich Jones was not diving, so I used his new G11 which was out on its virgin underwater experience.

There were many very colourful parrotfish about. This is simultaneously exciting, euphoric and frustrating. If you are a snorkeller or diver you understand the first two. If you are an underwater photographer you get the latter. Google parrotfish and look at the sad offering of images. It is nearly impossible to get close to them. You must depend on the occasional quick shot when one darts past:

I don’t know the species of the one above. My fish book is at the office and I have photographed so few that I can’t remember most of the names.

This one, I do know, but I would call it a “failed” image:

It is a Hump Head Parrotfish (Bulbometopon muricatum).  They are huge. This one was at least 1.5 metres long. Unfortunately, they are delicious and easy to spear. In some areas of the South Pacific they have disappeared completely. This was a quick snap shot at the end of a long tiring chase during which I managed to corner it long enough for a very poorly framed image. The closer you get to them the bluer they look. I was about two metres away from this one in fairly dirty water.

I’ve been playing around with a photographer’s technique called “deep focus”. It sounds exotic, but it is easy to understand. The smaller the hole you are looking through, the more “depth of field” you will get. In other words, objects from near to far will be in focus if the hole is small enough.

Theoretically, a pinhole will have a focal range from very close to infinity. So, the larger the number of the f-stop you use on your camera (the size of the hole through which the light passes) the smaller the hole will be. I know it sounds backwards, but never mind. Big number – small hole  – more depth of field. That’s the way it goes. If you can get f 16 on your camera, you will get lots of stuff in focus from near to far. At f 2.8 you will get only near or far, but not both.

It works better for non close-up stuff. For instance this shot of the Nudibranch Phyllidia varicosa  doesn’t show much effect:

Sure, most of it is in focus, but there is not much to show the depth of the image. There are no obvious visual clues to indicate depth.

It this shot of coral with an anemone in the background, however, there are many clues to indicate distance:

It requires a lot of light to use the small lens opening, because not much can get through. If you don’t have enough light, you will be forced to use shutter speeds that are too slow to give sharp images. There’s no free lunch. You can have it one way or another, but not both. I manually blurred and darkened the very distant objects at the top to enhance the effect.

In both of these images I failed to note that when I changed the mode of my camera to Aperture Priority (meaning I get to set the aperture and the camera automatically sets the shutter speed) I lost my format setting and it reverted to JPG. I always shoot underwater in the RAW format mode because it allows me much more colour control. Sorry to bore you with these arcane details, but there are a few photographers out there who are constipated enough to care about these things.

Here is a pretty scene, never mind the colours are off, of some coral with Purple Antheas swimming around:

It nicely illustrates the reality which you can get with the deep focus technique.

Okay, that’s it for me. It’s Sunday evening. The sun is below the yardarm. I’m going for a wee dram and lay on the bed to watch some mind-numbing TV for a while. Then maybe I’ll rest my eyes for a bit.

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10 Responses to “Parrotfish and Deep Focus”

  1. Steve Goodheart Says:

    Ah, some real beauties here, and I learned a lot about skillful camera work. Thanks, Jan!

  2. MadDog Says:

    Thanks, Steve. I’m thinking about doing a series of posts, maybe about a dozen, coming one per week, to teach basic camera skills to people who want to get better images with point and shoot cameras. Most cameras are capable of much more that the user knows about. Nobody wants to read the thick, opaque manuals. Most cameras have similar features. It only takes mastery of about a dozen easy principles to take professional looking images. What do you think of the idea? I could group them in the side-bar as I write them under “Easy-Pro Photo Tutorials” or something like that so they would be instantly available. I’ve covered most of the stuff already, so there would be a lot of linking back to old posts to illustrate with real images instead of a lot of talking.

  3. Steve Goodheart Says:

    Jan, that’s a fantastic idea! I would think it would be very popular and very appealing to lots of people, and you have terrific “creds” with your wonderful work.

    And, although I’m not a photographer, or photo geek, I can tell you as an editor that I found your technical (and what you often called “geeky” posts) to be very understandable to a non-photographer like me, so I think you’re “skill level” would be right on. (You did lose me a few times, but I think anyone with more than the rudimentary knowledge of photography that I had would have followed along easily.)

    I like the name “Easy-Pro Photo Tutorials” too.

    Go for it! It’d be a tremendous gift to many of your fans and readers, and who knows, this is the sort of thing that has developed into a book.

    Best wishes, as always,

    Steve

  4. MadDog Says:

    Yeah, Steve, that’s what I want to do. I happen to be pretty good at explaining things, probably because I’m not too smart myself. Once I break it down to the level that I can get it, most other people can follow my instructions.

    I’ve heard so many people moan that they can’t take good pictures. I’ve seen so many people making very elementary mistakes that I know were going to produce lousy shots. Simple rules like never backlight, keep the sun over your shoulders, get as close as possible, learn when to use flash and when you don’t want it cover about 90% of the errors.

    I think most people who really enjoy photography want to go further than that. Your encouragement is shoving me over the edge. I might have a go at it. I’ll have to think about the best way to present it. I think I want lessons to begin on the main page and then move over to a list of tutorials in the side bar.

  5. Steve Goodheart Says:

    I think what you envision will be a big help to many of us!

    And yes, the approach you outline in the last paragraph would be very appealing, and not be visually overwhelming, but welcoming.

    Look forward to seeing what develops. (Yeah, he says, ruefully, now i just have to find time for it! 🙂 🙂

    LOL! Go for it!

    Steve

  6. MadDog Says:

    I’ll give it a shot when I can find time to lay out a set of lesson plans. Don’t hold your breath.

  7. Steve Goodheart Says:

    Of course, as a fellow writer, and now, fellow editor, I totally know about time, which in spite of what the Rolling Stones say, is almost never on a writer/editors side!

    Good luck!

    Steve

  8. MadDog Says:

    Steve, I never thought that I’d be so busy at 66. At least my financial situation is improving. A side benefit is that I’ve broken my TV habit.

  9. Steve Goodheart Says:

    Hah, no rest for the wicked! 🙂 (which is why I’m so busy too!)

    Glad things are going better financially.

    TV was never big in my life, except for science shows and the like (and “Lost”) and now Sarah and I are very seriously considering doing away with our TV.

    Hope all is well, otherwise, with you and Eunie.

    Steve

  10. MadDog Says:

    I’m trying not to be so wicked these days, but old habits die hard, Steve.

    We just got our first new car in eleven years. I finally succumbed to Eunie’s gentle hints that she didn’t like “all that rust”. She’s so sweet. She can get anything she want’s with a smile.

    I had a terrible TV habit – just a huge waste of time. I have going nearly broke to thank for curing that. It just goes to show that it’s an ill wind that blows no kick in the ass for the lazy.