Tubes

[michaelb]

I've always wanted to pick up a set of extension tubes, but I've been put off by negative comments that I've read about them. Most people make it sound like their only for wedding photogs to take their ring shots!

Not having a macro lens for the 5D yet finally pushed me over the edge and they arrived today. Its a set of Kenko tubes that I ordered off of Ebay from Hong Kong for about $120 shipped.

I only used them for an hour or so tonight, but I must say I'm quite impressed and I wish I had picked up some of these along time ago.

20mm of ext tubes with the 24-105 is like macro with IS!! I also used the 70-200 with a full set of tubes, which is trickier to use.

I'll always keep the 20mm ring in my bag for use with the 24-105 when I don't want to carry a macro lens.

Here's a few from tonight. They aren't great shots as I only had an hour or so to play with them, but I'll definitely be experimenting more with these....(all on the 5D)....








24-105, 20mm tube, 105mm, f/7.1, ISO 200, 1/13, tripod....









70-200, full set of tubes, 159mm, f/16, 1s, ISO 200, tripod...








24-105, 20mm tube, 88mm, f/5, 1/30, ISO 400, hand-held, focus on center of leaf...








24-105, 20mm tube, 102mm, f/5, 1/30, ISO 400, hand-held..(focus on pink bud)...








24-105, 20mm tube, 85mm, f/4, 1/15, ISO 1600, hand-held....

[JMWallace]

I have to admit...

I actually looked over my shoulder to make sure my wife wasn't in sight of the monitor before I clicked.

Bummer.

[Rooz]

i;d like to know who the negative comments are from. tubes rock.

[TheWengler]

Maybe one of you geniuses can help me understand this. I saw somewhere recently that the formula for calculating the magnification of a lens when paired with extension tubes was this:

Magnification = Extension length / Focal length

Is that right? This doesn't factor in the current magnification ratio of the lens being used. So if you put a 25mm extension tube on a 50mm 1:1 macro lens would it reduce the magnification to 1:2? So does it only make sense to use extension tubes with non-macro lenses?

[Rooz]

i dont know the formula but putting exten tubes on a macro lens gives you larger than life size results. a full set of tubes on a macro lens significantly increases your magnification. i just dont know how to work out the numbers.

[drama]

The maths works out like this

Each lens at a given focal length has a fixed magnication, to which you have to add the extension tube length / the focal length

for a 50 mm lens with a magnification of say .5, if you add a extension tube the total magnification becomes .5 + (25/50) = 1

[TheWengler]

Thanks drama that makes much more sense.

[michaelb]

i;d like to know who the negative comments are from. tubes rock.

I've always heard people say that tubes were a pain to use and focusing was very difficult with them, etc, etc.

I had no problems with them however; I even used AF with most of these shots in order to obtain initial focus, without a problem. Once focus was achieved, I then switched to MF so the camera wouldn't keep trying to reacquire focus.

The only thing that was a little tricky was using the full set of tubes on the 70-200, only because the set-up was so long that it was a little unsteady. I had to wait for it to stop shaking before I took the shot (using MLU as well).

I would admit though that using this set-up to shoot moving subjects like bugs would probably be very difficult, but for the stationary objects that I like to shoot it works like a charm.

I have to admit...

I actually looked over my shoulder to make sure my wife wasn't in sight of the monitor before I clicked.

Bummer.

Now you sound like me.

My wife was commenting last night about all the boxes that have been arriving lately.

[adam75south]

weird. i was looking at extension tubes just the other day.

don't really have a need for them...except for the occasion ring shot haha.

[FLiPMaRC]

My wife was commenting last night about all the boxes that have been arriving lately.

I had my most recent lens purchase shipped here at work No boxes, not questions LOL