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I want to increase the magnification of my Canon 100mm L Macro. I already have a set of kenko extension tubes. Could I buy a dipter to even increase further the magnification? For example Raynox DCR-250?

Can I combine the two and which one would give me the greater magnification, the extension tubes or the raynox diopter?

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    \$\begingroup\$ Technically speaking, a diopter is just another way of moving the MFD closer to the front lens element. If you are already at the limit with extension tubes, adding a diopter won't really do much. \$\endgroup\$
    – jrista
    Commented Jun 27, 2012 at 20:31
  • \$\begingroup\$ Extension tubes or a dioptre filter can't generate magnification, they make the minimal focus distance smaller, reverting the lens can increase magnification. \$\endgroup\$
    – Nuno
    Commented Jun 27, 2012 at 21:38
  • \$\begingroup\$ @nuno: Actually extension tubes do increase magnification. Just like a normal lens used normally can shrink a tree down to the size of a 35mm frame, the same lens flipped around and moved far enough away can blow up something the size of a 35mm frame to the size of a tree. Of coures much much light will be lost and the tree will be severly cropped, but that nonetheless illustrates what is possible by moving a lens far from the camer. At 2x the focal length you get 1:1. Further than that you get higher than unity magnification. \$\endgroup\$ Commented Jun 27, 2012 at 23:50
  • \$\begingroup\$ Also relevant... How can I calculate what the effect of an extension tube will be? \$\endgroup\$
    – AJ Henderson
    Commented May 23, 2014 at 13:35
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    \$\begingroup\$ This has been covered extensively on the site already. Please see above links. \$\endgroup\$
    – AJ Henderson
    Commented May 23, 2014 at 13:36

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You can use this calculator to play around...

http://www.eosdoc.com/manuals/?q=jlcalc

I got close enough on a 1.3x crop just adding all three kenko extension tubes behind my Canon 100L macro. According to the calculator, that gave me a magnification of 1.45 (and then multiply by 1.25 to give 1.8).

That's at .25m. Keep in mind the lens plus body thickness to sensor is about .165m. So you really only have .085m working distance, or about 3.3". With the 500D (the 250D won't be able to focus), you'll have about 1.7" working distance with a magnification of 2.2. At f/16, you'll have DOF of 1/10th of a millimeter.

I captured the monarch egg with the extension tubes. But, I had a relaxing working distance of 3.3" and an enormous DOF of about 3/10ths of mm. :)

http://canid.com/monarch/thumbs.html

Monarch eggs are about 1.2mm tall, for reference, and these have been cropped slighty.

If you're going to do more than 1x life size, the Canon MP-E 65mm is what you want. A friend has that lens and creates remarkable macros.

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  • \$\begingroup\$ that calculator is just awesome! \$\endgroup\$
    – philberndt
    Commented Jun 28, 2012 at 15:35
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Yes, they will both increase the macro effect of the lens when used together.

However, it's not certain that all combinations of lenses, tubes and closeup lenses work together. An extension tube is constructed to be used with a lens without a closeup lens, and a closeup lens is constructed to be used with a lens without an extension tube. Each adds a bit of distorsion, so when used together you may get much more distorsion than you would get from using a longer extension tube or a stronger closeup lens.

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First, there is no such thing as a macro "filter". You probably mean a closeup lens. It may look like a filter at a distance because it mounts on the front of the lens like a filter does, but it is actually a single-element lens. Basically, it's reading glasses for your camera.

Second, there is no way to answer your question because "efficiency" makes no sense here. Efficient in what parameter?

It is possible to use extension tubes concurrently with a closeup lens. My main worry would be reduced optical quality, but that is higly dependent on the lens and the closeup lens. In general, closeup lenses usually reduce optical quality because they add yet another element to your overall lens, and the chromatic abberations of this lens can't be corrected by other elements.

Extension tubes have their own issues. There will always be some reflections off the inside walls onto the sensor, and it is using the lens in a way it wasn't designed for. I have one extension tube and lens combination that causes quite visible haze in the middle of the picture. Another drawback of extension tubes is that they don't generally pass thru all the communication (mechanical and electrical) between the camera and the lens, or they are very expensive if they do. At that point, you might as well buy a deliberate macro lens.

So the answer is that there is no general rule what works best with your camera, your lenses, and how you like to take macro shots. Experiment and see what works best for your setup.

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    \$\begingroup\$ I got electric pass-through extension tubes for my Sony NEX for about 25 EUR, 1/8th of what a macro lens would cost, and it works great. \$\endgroup\$ Commented May 23, 2014 at 13:39
  • \$\begingroup\$ @Michael: Yes, sometimes you can find good deals. I've seen some incredibly expensive name brand extension tubes too though. As with anything shop around carefully. In the same way, you can also get good deals on macro lenses. Your one case of 8x difference is just that, one data point. There will be quite a variety out there. Telling someone to compare a macro lens against a high end extension tube set is still valid advice. \$\endgroup\$ Commented May 23, 2014 at 14:53
  • \$\begingroup\$ IIRC, the better close-up lenses have two elements. \$\endgroup\$
    – JenSCDC
    Commented Oct 25, 2014 at 10:06
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Yes, macro photography can be done by using and combining multiple cheap methods (diopter rings, extension tubes and reverse mounting lenses) and here is an amazing example of what Alexey Kljatov achieved by reverse mounting old lens to a prosumer camera.

Link: http://chaoticmind75.blogspot.hr/2013/08/my-technique-for-snowflakes-shooting.html

Edit: Adding diopters, extension tubes and reversing lense changes it's characteristics, where the image is created, what is the magnification of the image, etc. For example if you add diopter to a lens, you can imagine it as "a new lens" with "new characteristics", that's why when you add even more extensions you can imagine them being added to that "new lense", changing it's characteristics even further.

Usually modifying your lens with various attachments could come at a price of quality, so if you are interested you can examine this experiment made by Wayne Schmidt. At the end you can see example of diopter and extension tube being combined.

Link: http://www.waynesthisandthat.com/closeuplenses.html

P.s. If you want to check out how it looks like to combine two extension tubes I recommend this video by ZY Productions.

Link: https://www.youtube.com/watch?v=kRini-FJ2f0

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Yes and the only loss in image quality will be due to the filter/magnifier as the tube/s only add a few cm of air to the light passage and air doesn't have any effect on light.

A lot of DSLR also have a digital teleconverter that you can use in conjunction with your tubes and filters/magnifiers.

I have a Sony SLT-a77 and a $130 tamron 70-300 macro zoom and a $300+ Tamron 90mm f2.8 1:1 dedicated Macro lens.

The tubes don't make a lot of difference when used with either macro lens but they have a massive difference when used with the kit lens

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