How to find the right lens filter size?

Finding the right lens filter size 

Finding the right thread size for your lens is pretty easy. On your lens, you need to find the universal symbol for diameter, which is Ø. The lens diameter will always have the Ø symbol before the number. This is not to be confused with the optical size of the lens. Take a look at the example below:


Take a really good look as it can be printed onto different parts of the lens, but if you can’t find it, then the lens diameter will also be found in the user guide that your lens (hopefully) came with.

You can use stepping rings to adapt a filter onto a series of lenses of different thread sizes, instead of purchasing a lens filter in the specific size for each lens that you own. If you only have one lens, then you won’t have this decision to make. But chances are you will come to own multiple lenses in the future, likely with different filter sizes. 


Pro-tip: Buy a lens filter to fit your largest lens’ front thread size. Then you can use this filter & step-up rings to adapt it to all your other lenses.

You want your filter to fit the widest lens (thread) diameter size. Imagine you have 3 lenses, lenses with thread sizes Ø49mm, Ø62mm & Ø82mm. All you would need to have a filter for all 3 is an 82mm lens filter, and 2 step-up rings, (Ø49-Ø82mm and Ø77-Ø82mm). Sometimes you will need to stack step-up rings to get to your desired size e.g to get from Ø49-Ø82mm you might need Ø49-Ø58mm and a Ø58-Ø82mm. Stacking can have undesirable effects like ghosting & should be avoided if possible.

Speaking of avoiding things, step down rings shouldn’t be used if you can help it. You can get away with it by moving down only 1 size (e.g. Ø82-Ø77mm) but any more than this and you’re going to experience vignetting around the edges of the image. 

Step-up rings are a very useful tool for any photographer or videographer who uses lens filters & has several lenses. You’ll have more space in your camera bag, and less space in your wallet because of the money saved!

Thanks for reading. Take a look at our product range to find filters & more.