How to Calculate the New MFD of a Lens When Using an Extension Tube

I recently received a comment on my popular article – The Ultimate Guide to Extension Tubes – which asked how you would go about calculating the new MFD (minimum focus distance) of a lens, once you have added an extension tube. In that original post I did include the mathematics for calculating the new maximum magnification of a lens with an extension tube, but at the time I decided not to dig deeper and explore the calculation of the new MFD itself, since the math is a little longer. The new comment reminded me about it, so I decided to …

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How to Stack Canon Extenders

Firstly, if you aren’t familiar with the use of extenders, sometimes called teleconverters, I’d urge you to read my existing in-depth guide to using extenders for your photography. Extenders allow us to extend the focal length of compatible lenses, and they come in a variety of magnifications. For Canon lenses, they are available in 1.4x or 2x variations, and we’ll be focussing on extenders for Canon cameras in this particular article. Stacking extenders simply means using more than one of them simultaneously, and for Canon lenses the solution is quite simple. On the other hand, the solution for Nikon lenses is much …

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Canon Vs. Kenko Extension Tubes

Extension tubes are a useful accessory that allows you to shorten the minimum focus distance of a lens by moving it further away from your camera’s sensor. In other words, it allows you to get closer to your subject and often create macro-like images without the need for a dedicated macro lens. If you aren’t yet familiar with extension tubes, I would first encourage you to read my guide: The Ultimate Guide to Extension Tubes. Having read the guide, or perhaps you already know all about the tubes already, you’ve obviously come to the conclusion that you’d like to buy some …

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