does an extension tube work well?

[awholelota]

I'd love to go out and spend $500 for a macro lens for my Canon 40D, but money is tight everywhere. I came across an extension tube on cl but I've never used one before so I'm not sure how good they'd be. Does anyone have experience with using extension tubes for macro shots? Also can someone be so kind as to explain how it takes any lens and turns it into a macro lens? This is the one I found. Any advise would be awesome. I have a 28-135mm on my 40D right now. thanks.

http://www.bhphotovideo.com/c/product/300603-REG/Canon_9199A001_Extension_Tube_EF_25.html#reviews

 

[BlueCorn]

Extension tubes can be quite useful. Basically they are just spacers that move the lens away from the camera body. The result is it reduces the lenses minimum focusing distance; increasing magnification. With the tube attached the lens is unable to focus on distant objects so it's not something that you want to leave on all of the time.

They generally work best on a prime (non-zoom lens) but can be used on either zooms as well. They aren't necessarily a direct replacement for a true macro lens but they would certainly get you closer than you can get with that lens now.

Since there aren't any optics in these, brand isn't that important. I have, and use, a set of Kenko tubes that work quite well.

Here are a couple of examples. Both of there were shot with a 100mm macro lens, 68mm work of extension tube and a 1.4x teleconverter:


Peppercorns and rock salt:

 

[awholelota]

very awesome. so there isn't any glass in there at all? i can just head to ebay and buy a cheapy tube? does it matter how long the tube is?

 

[BlueCorn]

No glass at all. You do want one that has electrical pass-through for your lens.

The Kenko one that I mentioned is a set of 3 that can be used separately or in any combination that you choose. That's what I'd recommend.

This is what I have:

http://www.bhphotovideo.com/c/product/375102-REG/Kenko_AEXTUBEDGC_Auto_Extension_Tube_Set.html

 

[awholelota]

Thank you! I'm guessing the electrical pass is for the auto focus?

 

[BlueCorn]

Autofocus generally won't work with the tube installed but you need the electrical connection to set the aperture.

 

[TitusvileSurfer]

I am a big fan of Kenko myself, and (not that it matters) shoot with a 40D as well.

 

[Ralph ATL]

great info

 

[awholelota]

very great info. one more question. does a tube change the amount of light i can get in my lens like a teleconverter would?

 

[BlueCorn]

Yes, there is some light loss. In camera metering will still work so you don't have to change how you physically adjust the exposure.

 

[maroun.c]

Just keep in mind that the distance you can work with will be very limited and that your DOf should be very thin. Other than that it does the job pretty nicely still not as practical as a dedicated macro lens.

 

[TitusvileSurfer]

Limiting the distance you are working with is the only point to using these in the first place. They should be used WITH a dedicated macro lens.

 

[awholelota]

Thanks, but as I said money is tight. Are you saying that these don't work at all for macro shots if not used WITH a macro lens?

 

[BlueCorn]

<a href=showthread.php?s=&postid=13690476#post13690476 target=_blank>Originally posted</a> by awholelota
Thanks, but as I said money is tight. Are you saying that these don't work at all for macro shots if not used WITH a macro lens?

If money is tight then a set of tubes will certainly get you closer to your subject at a lower cost than a dedicated macro lens. It's not a replacement for that gear but in my opinion it's a good investment.

 

[roxy25]

Here are a few with just Kenko tubes , these frags where on mt mag rack clost to the top of tank.

I like using the tubes with my macro lens to get super close shots.

 

[maroun.c]

You can find my last shots with Extension tubes and some with a reversing ring and extension tubes here:

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1495989

 

[TitusvileSurfer]

<a href=showthread.php?s=&postid=13690476#post13690476 target=_blank>Originally posted</a> by awholelota
Thanks, but as I said money is tight. Are you saying that these don't work at all for macro shots if not used WITH a macro lens?

As I said time and time and time again, DSLRs are very expensive. How often is the front of your lens going to be 1 inch away from the coral anyway? Come on your glass is practically that thick. I would take a Canon 100mm Macro lens over a set of tubes any day of the week no if's and's or but's. Now Canon 100mm Macro AND tubes? Yes please.

 

[roxy25]

<a href=showthread.php?s=&postid=13694868#post13694868 target=_blank>Originally posted</a> by TitusvileSurfer
As I said time and time and time again, DSLRs are very expensive. How often is the front of your lens going to be 1 inch away from the coral anyway? Come on your glass is practically that thick. I would take a Canon 100mm Macro lens over a set of tubes any day of the week no if's and's or but's. Now Canon 100mm Macro AND tubes? Yes please.

I agree I bought the tubes just for kicks , then bought my lens but both together = GREAT

 

[awholelota]

So with a tube I'd have to get super close to the subject in order to get a decent macro shot? I'm just trying to understand how they work, and what they're used for.

 

[BlueCorn]

<a href=showthread.php?s=&postid=13673996#post13673996 target=_blank>Originally posted</a> by beerguy
The result is it reduces the lenses minimum focusing distance; increasing magnification.

The actual working distance depends on the focal length of the lens and the amount of extension that you're adding. Since their whole point is to allow you to move the lens closer to the item they generally have to be much closer to the subject than you would be with a dedicated macro.