# Extension tubes and Reverse ring



## CK9

I'm new to macro photography and recently purchased a set of extensions tubes and a reverse ring to get started.

The extension tubes came as a kit of three which can be screwed together: 7mm, 14mm, and 28mm.

The reverse ring is a simple 58mm filter thread allowing me to reverse mount the stock 18-55mm Canon lens.

There are multiple different ways these tubes and rings can be combined to take macro photos, and I'm wondering if anybody can give me some pointers on how to create a good budget macro setup?

e.g.

Reverse mounting the lens to the camera without any extension tubes
Normal mounting the lens on to the end of one or more extension tubes.
Reverse mounting the lens on to the end of one or more extension tubes.

For options 2 and 3, the question is which extension tube(s) to use?  All of them stacked together (7+14+28)? A couple of them stacked together (e.g. 7+14, 7+28, 28+14)?

What I can tell so far is that option 3 seems to provide the greatest magnification but is very dark.  Option 1 seems quite bright but with less magnification.

Finally, I noticed that a final (4th) budget option is to purchase an adaptor allowing my 18-55mm lens to be reverse mounted on the end of a 55-250mm lens.  Any ideas where this fits in, in terms of performance and magnification?

Thanks!


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## dxqcanada

What you need is a nice fixed focal length lens to go with the tubes or reversal ring.
A 50mm is cheap to go with ... and it has a fairly short minimum focus distance.


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## Judobreaker

It kind of depends on what you want to photograph and how much magnification you want to achieve.
Basically all of the options you gave are possible.

Like said before: a 50mm prime lens is cheap and good to work with.
These lenses have a minimal focus distance of 0.45m which gives a 0.15x magnification (1 : 6.9).
Using extension tubes can give you the following magnifications:

*7mm:* 0.29x (1 : 3.5)
*14mm:* 0.43x (1 : 2.3)
*7mm + 14mm: *0.57x (1 : 1.8)
*28mm: *0.71x (1 : 1.4)
*7mm + 28mm: *0.85x (1 : 1.2)
*14mm + 28mm: *0.99x (1 : 1)
*7mm + 14mm + 28mm: *1.13x (1.1 : 1)

Keep in mind that some extension tubes do not have the means for communication between the lens and the camera so you'll have to do the setting manually.


Reverse mounting a prime lens is also a technique which can give good results.
It's a bit tough as you simply can't do the settings on the camera, you'll have to make sure to set the aperture and focus beforehand.
This is however definitely a very cheap method of achieving rather good magnification.

You can combine the two to get even higher magnifications.

Another possible trick is reverse mounting one lens on top of the other.
If you reverse mount a 50mm on top of another lens and put it's aperture wide open you'll have full control over the first lens so you can still control a lot from your camera.
This can also give you some real nice results.
I've never really studied this last method so my knowledge about it is fairly limited but it might be worth trying this technique if you have the means to.


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