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Just messing around with my Nikon D50 using a sigma 105 mm macro. This is a shot of a baby VP sinaloan.

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AIM sn: z10silver

Looks blood red! Derek

That IS awesome. I love that kind of abstract detail. Now try the black/white/red intergrade.
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Vichris
"The object of life is not to be on the side of the majority but to escape finding oneself in the ranks of the insane"- Marcus Aurelius

Vichris Variables

I love taking scale shots. Here's a montage -

You should get yourself a set of extension tubes to really fill the frame with the scales. Generally, though a 1:1 macro (like the Sigma 105) and some cropping can get you pretty close.

Here's my take on a milksnake -

I have a whole collection of scale shots here - Snake Scales Photographs
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Chris Harrison
San Antonio, Texas

Wow, those are all impressive. What exactly is an extension tube and how does it work?

Thanks
Zach
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AIM sn: z10silver

An extension tube is basically a hollow tube that goes between the lens and the camera body. By "extending" the lens further away from the sensor, it increases how close you can focus and the total magnification possible. Unlike teleconverters or screw-on diopters, however, they don't contain any glass elements so they don't degrade image quality at all.

You can by them separately (i.e. a 25mm extension tube) or as a set of 3 (usually something like a 12mm, 20mm, and a 36mm tube). You can use multiple tubes together so all three will give you 12 plus 20 plus 36 = 68 mm of total extension or any combination of the three. Single tubes run about $50, but you can usually get the set of three for around $100. It is a cheap way to get high magnifications, as long as you can get close enough to the animal.

How much extension you use determines the magnification. You calculate magnification by using

total magnification = total extension / focal length

Your Sigma 105 already goes down to 1:1 magnification, so it must effectively have 105mm of extension built in. If you added another 73mm of extension (the set I described above), the total magnification would be = (105 plus 68)/105 = 1.65x.

Because of the way extension works, shorter macros get more increase in magnification. The same 73mm of tubes on a 50mm macro lens would give you (50 plus 73)/50 = 2.36x magnification.

Most modern extension tubes are "auto" extension tubes which are specific for your camera mount. They can communicate between the lens and the camera, allowing autofocus, autoexposure, etc., to work. Kenko make a decent set for most camera brands.

The only down side to extension tubes is that you lose the ability to focus to infinity when you have them on.

This shot (Black Milksnake) was taken with a 90mm macro and 68mm of extension -

and the same three tubes on a 50mm macro lens -

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Chris Harrison
San Antonio, Texas

Chris,

Are those photos with the extension tubes cropped/blown up at all?

If I'm to understand, extension tubes allow you to focus closer, correct? As in, if the normal closest distance to focus is 1 foot, by adding extension tubes, it'll allow you to go to, say, 6 inches?

I may have to invest in some extension tubes along with everything else, haha.

Are those photos with the extension tubes cropped/blown up at all?

Yes, some of them are cropped a little. The limitation isn't the magnification, but actually how close you can get to the animal and still get lighting on it as well. Often if you get too close, the lens will shade the lighting.

If I'm to understand, extension tubes allow you to focus closer, correct? As in, if the normal closest distance to focus is 1 foot, by adding extension tubes, it'll allow you to go to, say, 6 inches?

I don't know exactly how much closer (it depends on the lens and amount of extension), but yes, you can get closer and therefore have higher magnification.
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Chris Harrison
San Antonio, Texas

Chris,

All of your photos are great. Can I ask what kind of flash setup you have? I have not been using mine at all as the on camera flash seems too harsh and I think I may need a diffuser. Also, I have been having some trouble getting sharp focus when shooting at a distance. Is this typical of a macro lens, or should it be just as sharp far away as it is up close?

Thank you
Zach
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AIM sn: z10silver

Can I ask what kind of flash setup you have? I have not been using mine at all as the on camera flash seems too harsh and I think I may need a diffuser.

I use a variety of flashes and setups. For most of these shots, I used a Konica Minolta 3600 HS-D flash (GN=118 feet) with a Stofen Omni-bounce diffuser on it. Some of the shots the flash is on the camera, other times it is handheld and operated wirelessly by my camera body.

The Stofen Omni-bounce diffusers are great. They give nice light and are really field hardy and easy to use (since they are plastic!).

Of course there are lot of other good diffusion options.

I recently bought a pair of these. A guy near Houston sells them two at a time on ebay - cgi.ebay.com/2for1-NEW-FLASH-DIFFUSER-Mini-PANELS-Photo-Accessories_W0QQitemZ270101728823QQcategoryZ64354QQssPageNameZWDVWQQrdZ1QQcmdZViewItem. They are really great little things and for $12.99 plus shipping per pair, you can't beat the price. You could sell the other one to another photographer for $10, probably. It works great with both my large flash heads and my on camera flash.

A lot of people make diffusers out of tissue paper, plastic milk cartons, etc. It isn't rocket science. The problem with the homemade ones is they are usually flimsy.

Also, I have been having some trouble getting sharp focus when shooting at a distance. Is this typical of a macro lens, or should it be just as sharp far away as it is up close?

A good macro lens (like yours) should be sharp from 6 inches to infinity. Make sure it isn't a focus issue. Try manually focusing and see if it still doesn't get tack sharp. Also try using a tripod and photograph something that can't move in the breeze and shoot using a 2 second delay or a cable release if you have one. If that shot isn't sharp, it could be your lens.

You might have a lens that backfocuses/front focuses a bit. If that's the case, Sigma should fix it.

Chris
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Chris Harrison
San Antonio, Texas

I love that montage and the photobucket pics are the best I've seen. I may have to attempt that with some of my thayeri.

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Vichris
"The object of life is not to be on the side of the majority but to escape finding oneself in the ranks of the insane"- Marcus Aurelius

Vichris Variables