Tena koutou katoa (greetings, in Maori) from New Zealand

Lets get to know each other better. Here's a forum to post images and short autobiographies of ourselves as well as any other info you would like to post about yourself.

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rjlittlefield
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Post by rjlittlefield »

Ted,

This is where "long-distance debugging" gets tricky.

In your image, the highlights I'm talking about are not on the insect, they're on the background.

So I'm pretty comfortable with the diagnosis that the camera moved (unless the glass did).

One of the difficulties of shooting macro is that it's much more sensitive to camera motion than ordinary photography.

Without having hands-on your equipment and watching your procedure, I can't tell exactly what's going on.

At these magnifications, it's quite possible for mirror & shutter vibration to cause visible image movement, especially if gear is set up so that the end of the lens is a long ways away from the tripod. Usually those movements are vertical, since that's how the mirror rotates and in most cameras is how the shutter curtains move. That argues against this cause for this picture, since the streaks are horizontal. But some cameras are different, and the direction of movements can change depending on how things are connected together. And of course if you cropped and rotated, or if you had the camera mounted in "portrait" orientation, then the camera's vertical would become the image's horizontal, and mirror/shutter movement would again be a plausible explanation.

If you were looking through the camera when you took the picture, then one possibility is simply that your face brushed the camera, moving it a hair one way or another. Another is that when you triggered the cable release, you tugged on the camera just a little bit -- it's really easy to do.

I suggest to set up your gear and practice on subjects that absolutely positively are not moving. Dead flies are perfect. Set up the picture, step back, use the cable release, and be sure not to move while you're doing that. If your images then do not have motion blur (streaks and/or doubling), you'll know that mirror & shutter motion is not your problem. Or the other way -- if they are still blurred, then mirror & shutter is your problem.

By the way, another source of overall blur can be stopping down too far. With a subject this small, if you set the largest f-number that's on the lens, in search of more depth of field, then you're liable to run into trouble with an effect that photographers often call "diffraction blur". See http://www.photomacrography1.net/forum/ ... hp?p=15854 for a very brief introduction/illustration to that issue.

One way to tell the difference is to look at the "shape" of the blur. If the blurs are streaked in one direction, motion is to blame. If the blurs are symmetric -- just fuzzy circles instead of sharp points -- then the problem is probably being out-of-focus or being stopped down too far.

--Rik

Ted Chappell
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Ah, I see what you mean

Post by Ted Chappell »

Heck, this field sure has a lot more details to take into consideration compared to what I am used to. Bigger challenge, bigger satisfaction. I will take all the helpful suggestions/advice you and the other posters have so generously provided and practice, practice, practice. Like the idea of the dead fly etc.

Thanks again
Ted
Totally new to Macro and this site, so very keen to learn from others, and from viewing the works posted. http://www.pbase.com/tedchappell/galleries

rjlittlefield
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Post by rjlittlefield »

Simply: will adding a bellows to my Macro 100 lens give me closer images that do qualify as Macro?

Not to worry -- you don't even need the bellows.

A 6 mm fly almost filling the frame is definitely macro.

--Rik

DaveW
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Post by DaveW »

To me the moth itself simply looks out of focus Ted. Were you using manual focus, or autofocus, because autofocus is not accurate close up? I switch to manual focus and screen focus.

If you use flash with a too slow shutter speed in very bright ambient lighting you can get ghosting too where the flash image records then if the subject (or camera) is moving a slightly blurred image from the ambient light.

Also as Rik says it is movement in the horizontal direction, sometimes even not having the tripod screw tight enough will allow the camera to move slightly sideways, particularly if you are not using a cable release. However flash should have frozen that, unless ambient light recorded as said above.

DaveW

rjlittlefield
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Post by rjlittlefield »

Ted,

Dave raises some good points I didn't think to mention. As follow-on discussion...

To learn macro, manual focus is a must. With auto focus, you're never quite sure what it's going to do, and it's liable to do something different every time. After you learn the art, then sometimes you can go back to auto focus and take advantage of its faster operation. But wait until you have basics well in hand to do that.

Depth of field (DOF) is always very limited in macro work. Usually this "feature" is quite annoying, but you can take advantage of it as a learning aid.

The trick is to set your subject on some finely textured surface, say a fuzzy leaf (fine hairs) or a piece of fabric or fine sandpaper. Set up your camera to shoot at an oblique angle, say 45-60 degrees away from perpendicular. When you do this, the plane of focus will be easily seen as a line of sharp detail across the surface. Both in front and in back of that line, detail will be fuzzy (blurred). If your focus is properly set on the subject, and the subject is very deep, you'll see that it gets blurred too both in front and in back of the plane of focus. Or if you've missed focus entirely (it can happen!), you can tell that by looking where the focus line is on the surface, versus where the subject sits.

In addition, if you shoot this same scene, changing your aperture setting from wide open to the biggest f-number you can set (and of course adjusting your exposure time or flash intensity to match), you'll get a good feel for both how much DOF you have to work with, and also how far you can stop down before things get blurred.

Dead flies and fuzzy leaves make great practice subjects. :wink:

--Rik

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