tom_benedict

Take a look at sci.astro.amateur. Luckily it's not as crowded with crazies as the other sci.astro groups, and I can gurantee you the topic has come up recently.

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To directly photograph the eclipse (i.e. camera pointed at the sun), you must use a filter. No, make that you *MUST* use a filter. Even that may not be enough emphasis...

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If you plan to look through the viewfinder, get a filter that's ok for use with your eye. Thousand Oaks Optical makes several fine ones of this grade. A #7 welder's glass is NOT 100% protection, nor is most mylar. You can get mylar that's designed to block UV for human eye viewing, but if it wrinkles and gets pinholes, you're up a creek.

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If you don't plan to look through the viewfinder, your options are a little wider. I've even used two sheets of TMax 100 that had been over-exposed and developed. They give the image a nice ruddy tint. They also do very little to block UV, and will do an excellent job of blinding you if used incorrectly.

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An alternative is to photograph a projected image of the sun. Some of the neater eclipse pictures I've seen have been projected images. Pinholes, trees, even a salt-shaker top can project a neat image during a partial eclipse.

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Whatever you do, play it safe. The machine shop I used to work in had a sign by every lathe and mill: "You only get one set of eyes. Wear protection." The sun is a runaway fusion reactor. If I'm cautious around an end-mill, I'm even more cautious around nuclear reactors.

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Tom

You know, I never really thought about it that way, but I guess contrastier films and papers do tend to give worse shadow details.

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There is one other thing you can do. I've never tried this with print film, but it does work with slide:

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Pre-expose the film. With slide film, I'd set things up so I'd get a completely uniform blank field (translucent film lit from behind works well), and under-expose by two and a half or three stops. This doesn't produce an image, but it does dump in enough light that practically ANY exposure will result in an image. This makes the film slightly less contrasty, but it results in really good shadow details.

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The one gotcha I ran into with slide film is that you can over-do this to the point where you don't get ANY black. This looks lousy. With print film there's a little more leeway in the printing process, but I'd still be leery of over-doing it when you pre-expose.

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Ansel Adams has a nice section on this subject in "The Negative". He's definitely a better reference than I am.

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Tom

This may or may not work, depending on where you are, but one of my favorites is scorpions. They're nocturnal hunters, and are active when it's warm and dark out.

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And they fluoresce under a blacklight.

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This makes them very easy to spot. Get a battery-powered blacklight ($14 US for the tube, plus around $10 for a fluorescent flashlight), and use this to spot them. Good places to find scorpions are wood piles, piles of twigs and leaves, rocks, or anything else with nooks and crannies for them to hunt in.

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Once you find one, it's up to you what you do with them. Straight flash photography work well, but they also look really neat under tha blacklight. I've done a number of nice images this way, but don't have any of them scanned in.

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Millipedes, centipedes, and some flowers also fluoresce under UV illumination. Go wild.

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Tom

Lot sure about local suppliers, but Edmund Scientific, Altex Electronics, Digikey, and Newark should all carry fiber.

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Whether you can get a piece as short as one foot is another question. For lengths that size, you might check at a local networking and cabling contractor and see if they have any scraps lying around. Most mail-order houses have minimum orders around $20 US. That'll buy a LOT of fiber.

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I've got to ask you a question in the hopes you can relay it to your fellow photographer: How big a landscape are you photographing? Directly fitting a fiber onto the end of a Maglite is great for doing macro work or studio work, but it won't be able to throw the light very far. If you're trying to light up big chunks of the landscape, you might do better to take the fiber off and use the Maglite directly.

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But who am I to question your methods. I'd imagine a field of flowers photographed where each flower glows with its own inner light (each carefully painted using the fiberlight you're describing), would look pretty darned neato. Please ask your fellow photographer to post the results! Enquiring minds (like mine!) want to see.

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Best of luck,

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Tom

Here's a neat mental-floss exercise: Next time you're outside and see the moon, hold your thumb at arm's length and hold it next to the moon. Get a feel for how big it is.

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Next time you see the moon low on the horizon and say, "Hot diggity, that moon is HUGE!", stick out your thumb at arm's length and hold it next to the moon for comparison...

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It's not so much a case of, "Your camera won't record what your eyes see," so much as it is a case of, "But my photo doesn't convey what I felt when I saw it!"

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Here's another example: A knee-jerk reaction a lot of people have when presented with a wonderful sweeping vista is to stick on the shortest, widest lens they have and try to capture it all. The resulting photograph is usually pretty flat, and in no way conveys the grandeur the photographer might've felt at the time.

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The moon on the horizon is the same kind of thing. The angular size of the moon isn't going to change that much, but the way in which you percieve it will. Rather than saying, "Hot diggity, that moon is HUGE!" say, "Hot diggity, that moon looks HUGE compared to the tree beside it." Now you're getting there. If you can use a long enough lens to make that tree big in the frame, the moon will be big as well.

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Tom

Yahoo! A chance to mix my passion (photography) with my education (astronomy). Previous answers have pegged the cause (dewpoint), so I won't go into that.

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Dew is something amateur astronomers run into constantly. Being a feisty lot, they have come up with a number of ways to beat dew. Here are some of them:

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Keep the glass warmer than the dewpoint - Some astronomers use hair driers to keep exposed glass warm. You can also get heater strips you can wrap around the end of your telescope, or you can make your own (a series of resistors epoxied around the glass, hooked up to a low-current voltage source works well).

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Keep moisture away from the glass - Schmidt-Cass designs are especially prone to dewing because there's no sort of hood to keep moist are off of the glass (as opposed to a Newtonian, which is practically ALL hood.) Many amateur astronomers make or buy hoods for their telescopes. The longer the hood, the better it tends to keep dew off. Be careful of vignetting, though.

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Keep air flowing over the glass - A small fan blowing on the glass will keep dew at bay for a while.

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For a good time, flip through the back of a Sky and Telescope or Astronomy Magazine. Ads for products with names like "Dew Busters" always make me smile.

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Tom

For the most part I do photography where I live, and in the Southwest. I know the weather patterns and seasons, so I know more or less what to expect before I head out the door.

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This time I'm stumped. I'm going to be on Hawaii's big island at the beginning of November. I have a week, 30 rolls of film, my bag of gear, and a credit card. I've read what I can about Hawaii, and have some ideas, but I'm still stumped.

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This is the first time I've ever gone somewhere with photography in mind, and have practically NO idea what to expect. None of the books I read mentioned seasons, so I don't even know if the time of year matters. None mentioned temperature, though some friends who have worked on Mauna Kea told me altitude requires warm clothing, no questions asked. I have a tentative route laid out, but nothing really solid.

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I know I shouldn't expect to take really good pictures my first time in a new place, but I figure knowing SOMETHING about the place should help my chances.

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Any pointers?

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Tom

I'll actually take a different tack on this: For people who already have a camera body, are there any inexpensive ways to get into a branch of photography they can't currently do?

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Here's an example: Closeup photography

Obvious ideas are two-element closeup lenses, extension tubes, and the like. Another idea is to reverse-mount a lens you might already own. Heck, if you have a lens in the 80-130mm range, reverse-mount your 50mm onto the end of it. You wind up with significantly more than 1:1 magnification, and all it cost was about $15 US for a filter reversing ring (or nothing if you just held the lens up there.)

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Is it cheap? Relatively so, yes. Are the necessary parts available? Yes, even more so if you already own them. Can they create high-quality, salable images? You betcha.

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Any other ideas? (No, I don't expect someone to come up with a way to build a high-quality 500mm f/2 optic from a magnifying glass, string, and an old doorknob, but...)

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Tom

The answer I'd give is a qualified "yes", but there are a lot of factors that go into making a picture fuzzy:

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Are you using an appropriate shutter speed? A good example of this is an airshow. Airplanes parked on the ground can be photographed with shutter speeds of a second or longer (with the camera bolted to a good tripod.) Jets doing a fly-by may not turn out well, even when shot at 1/500 of a second.

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Are you positive you've got the lens focused? I can't tell you how many of my dragonfly pictures wind up in the trash because I focused on the wrong part of the bug.

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Do you have your camera firmly affixed to a good quality tripod? (If you don't believe this, try a series of shots where you hand-hold one, and shoot the same shot off of a tripod. You'd be amazed.)

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Are your lenses clean? I've noticed a number of people keep filters permanently affixed to their lenses to protect them, but never clean the filter itself. This is good for when you eventually sell the lens, but it's gonna make your pictures look fuzzy.

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Are you catching flare? Zooms, especially, tend to flare out when hit with bright light. Make sure you use a lens hood, shield the lens with your hat, whatever.

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Are you using an aperture where the lens performs well? Along with increasing or decreasing depth of field, the aperture can also change how badly the optical abberations in your lens affects the image. Many soft-focus lenses (typically designed with intentional spherical abberation) get sharper as you stop down.

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I'll stop there. The gist of what I'm saying is that before condemning a lens as unsharp and spending hundreds or thousands on new optics, make sure it's the lens and not your technique that's causing the problem.

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Tom

This is partially re-iterating what others have said, but for what it's worth:

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There are generally four ways to do closeup photography:

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Closeup lenses - These screw onto lenses you already own, and can get you pretty close (about half life-size if you push it.) Advantages: Low cost, no loss of light. Disadvantages: Some degradation in image quality. (As someone else pointed out, if you're going this route, buy high-quality two-element lenses.)

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Extension tubes - These mount between your camera and lenses you already own, and can get to life-size (with enough extension.) Advantages: Low cost, no optical elements, so they don't degrade the image (unless the lens you use really performs badly when used that way.) Disadvantages: Loss of light, two full stops at 1:1.

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Bellows - These mount between your camera and a lens. Typically bellows are used with short-mount lenses (lenses without a helical focusing mount on them.) Advantages: Flexibility (you can always rack out further), and flexibility (some allow for shifts and tilts). Disadvantages: Low-durability, light loss (same as an extension tube), and the minimum extension is usually 50mm or so. So if you're using this with a 50mm lens, you're starting at 1:1 and getting closer...

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Dedicated macro lens - This is basically a highly corrected optic with an extra long focusing mechanism. The extension is essentially built-in. Advantages: This is the most convenient way to do closeup photography. Disadvantages: This is the most costly way to do closeup photography.

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One side-note: Zoom lenses with a "macro-focus" feature are NOT macro lenses. These really don't let you get a high enough magnification to qualify.

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By all means, pick up a copy of John Shaw's "Closeup on Nature". This is an excellent read, and covers a great deal more ground than I can.

I'd be lying if I said, "Weather has no hold over me when it comes to photography!" But I do often find myself outdoors with a camera under less-than-ideal conditions.

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One reason for this is that I often go out with a group of friends who are avid lightning photographers. It may be one in the morning, and I'll get a rough shake and a, "Weather radar says a thunderstorm's coming. Pack your gear." Half an hour later, I'm awake (sort of), packed, and walking out to a good spot.

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Another reason is that bad weather, even completely non-photogenic bad weather, can be neat simply because people normally DON'T go out under those conditions. A little over a year ago, my father, wife, and I were staying on Mustang Island off the coast of Texas. I normally get up to catch sunrise, but the sky had been overcast the entire trip. One morning I got up, threw my gear in the car, and headed out. Just as I was pulling out, my father walked up, handed me some coffee and jumped in. The weather was terrible, even for photography. Completely monotone sky, high wind with blowing sand, and a dull sea. But we stood outside waiting, anyway. In a split-second, everything changed. The sky was still all one color, the wind was still blowing, and I was still drinking sandy coffee, but there was some quality about the scene that had just subtly, but definitely changed. The sun had come up.

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I don't always get out when the weather is stormy, and my gut reaction to bad weather isn't always, "GREAT!! Get the cameras!" But I've had some unique experiences in so-called "rotten" weather. I wouldn't trade them for anything.

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Tom