The filter size doesn't really make a difference, it's the size of the shape. what you are doing is essentially opening your lens aperture as wide as it will go (smallest F-stop number) and letting the shape control the size of the aperture for you. You want the shape fairly large, but not taking up the whole disc. if the shape is too small you won't get much effect because there will be more in focus than there should be.
If you look at the image in the article showing the discs with the shapes cut out, you'll notice that they take up the whole center, but not the whole disc. This will be the same no matter the diameter size of the lens you want to fit it to.
It will make more sense if you know how aperture works
You notice in the picture that the bigger hole has a small f-stop number and the image has a shallow depth of field ( blurred some), the small hole has a bigger f-stop number and the image has a wide depth of field (everything in the frame in focus= no bokeh)
The bigger the shape in your disc, the more dramatic your bokeh will be. The only limitation is that no matter how big you make your shape, you cannot not achieve a smaller f-stop than your lens is capable of.
Hopefully this is understandable, aperture is not the easiest thing to learn :/
thanks Shannon- that is exactly what I needed! I was trying to make the shape small- duh, but now that you explained it it makes perfect sense. Going to try this out now as it super sunny out today! Thanks for taking the time to explain this further :)
Tweets ahoy!
Join the Group
Pin With Me
If you look at the image in the article showing the discs with the shapes cut out, you'll notice that they take up the whole center, but not the whole disc. This will be the same no matter the diameter size of the lens you want to fit it to.
It will make more sense if you know how aperture works
http://blog.girlsbydesign.com/wp-content/aperture.jpg
You notice in the picture that the bigger hole has a small f-stop number and the image has a shallow depth of field ( blurred some), the small hole has a bigger f-stop number and the image has a wide depth of field (everything in the frame in focus= no bokeh)
The bigger the shape in your disc, the more dramatic your bokeh will be. The only limitation is that no matter how big you make your shape, you cannot not achieve a smaller f-stop than your lens is capable of.
Hopefully this is understandable, aperture is not the easiest thing to learn :/