Helpful Posts:
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25th February 2011, 01:13 PM
#1
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25th February 2011, 01:19 PM
#2
Re: Can this be real
Can't speak for this particular brand but the extension tubes I have for my Canon give me full control of the lens as if it was directly attached to the camera.
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25th February 2011, 01:58 PM
#3
Re: Can this be real
Its just a set of extension tubes, they have been available since the dawn of time.
The further you move the lens from the imaging plane (film/sensor) the greater the size of the image circle it projects so essentially you are doing cropping into the scene - easiest and most effective way of getting higher macro magnification.
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25th February 2011, 04:44 PM
#4
Re: Can this be real
The important things with an extension tube (set) are that
1. There is a connection between the camera and the lens to maintain auto-focus and exposure (although I most often manually focus when shooting macros). Many of the cheapie extension tubes advertised on eBay allow you to neither focus nor control the exposure. This set looks like it can do this.
2. That the extension tube set is compatible with your camera. Some Nikon cameras are compatible with only certain lenses... I hope a Nikonian will fill in this data.
3. The tube will fit the lens that you are using.
Tubes will provide close-up/macro capability for non-macro capable lenses and will increase the image ratio for macro capable lenses. There is no image deterioration with extension tubes since they contain no glass, but simply allow the lens to sit further from the focal plane. They do however require increases of exposure for which your camera's meter will compensate.
A caveat: Macro lenses are optimized for close focus work. They are not just able to focus closer, they provide exceptionally sharp imagery when doing macro work.
I purchased a 90mm f/2.8 Tamron macro AF SP lens for my EOS Canon camera on eBay for about $100 plus a few bucks shipping. I have seen these lenses in various mounts on eBay for similar prices. You just have to be patient and keep haunting the used photo equipment web sites. That would be a far better way to achieve macro imagery than extension tubes. I can focus from infinity to 1:1 imagery with this lens and the IQ is exceptional. I looked on eBay just now for a used Nikon mount Tamron but, there were only used Canon mount Tamron macro lenses available.
NOTE: I am not sure about your Nikon's compatibility with manual focus lenses from other manufacturers but, my Canon EOS cameras will work with several types of manual focus macro lenses which can often be had at a low price on eBay or on other used equipment forums. Since much macro work is manually focused, having a manual focus lens would be no great problem.
Last edited by rpcrowe; 25th February 2011 at 04:51 PM.
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26th February 2011, 03:39 AM
#5
Re: Can this be real
Yup, they'll work. The electrocal signals simply pass through the extension tube allowing the camera to communicate with the lens.
I'd love to find a set of Sigma SA mount extension tubes that would do this.
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26th February 2011, 04:03 AM
#6
Re: Can this be real
Extension tubes can be great but I would definitely say watch out for third party or off-brand tubes. Canon or Nikon brand tubes are going to be a lot more expensive but they're definitely worth it. My brother-in-law has a set of Kenko tubes that I just hate because the mounts aren't machined perfectly (shortcuts to save cost) and so the don't fit snugly. They're loose and they rattle making the lens wobble which is exactly the opposite of image stabilization. My canon tube fits just beautifully. I watched ebay like a hawk and got a second-hand 25 mm Canon tube for US $50.00- they go for $140 new.
Another note on tubes is that they are best used on dedicated macro lenses anyway. I have Canon's 100mm f/2.8L IS macro lens (a real treat of a lens to use) which focuses to 1:1 or life-size. With the 25 mm extension tube I get down to 1:1.39 or 1.39 times life size making for some really amazing macro shooting. Most regular lenses can't even get down to 1:1 with a whole stack of tubes and with too many the problem that arises is that your focal point can actually be behind your front element. So in other words the whole stack they have shown on the site is somewhat unrealistic in most scenarios.
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27th February 2011, 07:17 PM
#7
Re: Can this be real
Extension tubes work great - I use them a lot.
There is one drawback - infinity focus will be lost - in fact more than infinity focus will be lost - potentially much more.
With a 100 mm macro and 12 mm of tube on my 5DII, with the lens set to infinity, the maximum sensor to object distance that will be in focus is about four feet (1.2 metre). Note that 12 mm is usually the shortest tube in a set.
With all three tubes (12 mm + 20 mm + 36mm) the maximum sensor plane to object distance in focus is about 16 inches (400 mm). With the hood on (it's quite long), the end of the hood is about three inches from the farthest object that can be in focus. And the DOF is essentially zero.
Glenn
PS - mine are made by Kenko - no wobbling at all. They will rotate a small amount but this won't affect the image (a lens is axially symmetrical).
Last edited by Glenn NK; 27th February 2011 at 07:27 PM.
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27th February 2011, 07:45 PM
#8
Re: Can this be real
Just to add some interesting point of view on the extension tube capability. This guy can really produce stellar macro shots using an inverted 50mm lens coupled to an extension tube. You can view his work here:
http://www.youtube.com/watch?v=wqRn3...eature=related
http://www.flickr.com/photos/opoterser/4887249906/
and here, too: http://thomasshahan.com/
I'm actually leaning to buy one though still have to save some more moolah for a good extension tube.
Last edited by jiro; 27th February 2011 at 07:51 PM.
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