Aperture refers to the size of the opening in a lens that lets light through. The larger the opening, the more light that comes through to hit the sensor or film.
Back in manual cameras days, most lenses only let you set the f-stop at defined increments, usually of a full stop at a time. So you could choose ƒ/4 or ƒ/5.6, but there was no way to choose ƒ/5.
With today’s digital cameras controlling the aperture, we have much more fine-grained control. Even lenses that still have an aperture ring, such as the Sony FE 24mm ƒ/1.4 GM, the available increments are often much smaller than a full stop.
So we’re not limited just to these larger steps but can instead now set the shutter in 1/3 stop increments. But because of the way aperture is denoted, with figures such as ƒ/1.6 or ƒ/1.8, it’s not particularly self-apparent what the jump between one value is to another–unfortunately it’s not as simple as a basic decimal system. So if you’re trying to calculate the effect on other parts of the exposure triangle. Of if you’re using a neutral density filter, for example, it can involve some head scratching to work out what aperture you need to factor in an 8-stop ND filter–at least, it does for me. (If you find yourself in this situation working with very dark ND filters, there are some good phone apps that can help–search for something like “nd filter calculator.”)
I’m posting this F-stop chart here partly for my own reference and partly in case others find it useful. It covers the working aperture range of the majority of digital photography lenses on the market, which typically falls somewhere within the ƒ/1.2 through ƒ/32 range.
The column on the left represents full stops. So the jump from ƒ/5.6 to ƒ/8, for instance, is a full stop.
The second column shows 1/2-stop increments. So a 1/2 stop down from ƒ/5.6 is ƒ/6.7.
The third column shows 1/3-stop increments. So going from ƒ/1.4 to ƒ/1.6 is a third of a stop.
| Full Stops | 1/2 Stops | 1/3 Stops |
|---|---|---|
| ƒ/1 | ƒ/1 | ƒ/1 |
| ƒ/1.1 | ||
| ƒ/1.2 | ƒ/1.2 | |
| ƒ/1.4 | ƒ/1.4 | ƒ/1.4 |
| ƒ/1.6 | ||
| ƒ/1.7 | ||
| ƒ/1.8 | ||
| ƒ/2 | ƒ/2 | ƒ/2 |
| ƒ/2.2 | ||
| ƒ/2.4 | ||
| ƒ/2.5 | ||
| ƒ/2.8 | ƒ/2.8 | ƒ/2.8 |
| ƒ/3.2 | ||
| ƒ/3.3 | ||
| ƒ/3.5 | ||
| ƒ/4 | ƒ/4 | ƒ/4 |
| ƒ/4.5 | ||
| ƒ/4.8 | ||
| ƒ/5 | ||
| ƒ/5.6 | ƒ/5.6 | ƒ/5.6 |
| ƒ/6.3 | ||
| ƒ/6.7 | ||
| ƒ/7.1 | ||
| ƒ/8 | ƒ/8 | ƒ/8 |
| ƒ/9 | ||
| ƒ/9.5 | ||
| ƒ/10 | ||
| ƒ/11 | ƒ/11 | ƒ/11 |
| ƒ/13 | ƒ/13 | |
| ƒ/14 | ||
| ƒ/16 | ƒ/16 | ƒ/16 |
| ƒ/18 | ||
| ƒ/19 | ||
| ƒ/20 | ||
| ƒ/22 | ƒ/22 | ƒ/22 |
| ƒ/25 | ||
| ƒ/27 | ||
| ƒ/29 | ||
| ƒ/32 | ƒ/32 | ƒ/32 |
| ƒ/36 |
ANDREW POULTER says
Do professional photographers use full stops on there controls or use 1/3 stops on ISO , speed , aptures, If so wot is the advantage.
David says
I’m not sure that there’s one “right” answer. Different photographers have different preferences and needs. I personally use the smaller increments on cameras that support them because I like the potential for fine-tuned exposure. It’s especially convenient when using a partially automatic mode like aperture priority or auto-ISO, and even for settings like exposure compensation, where having partial stops available gives you much more control to get it just how you want it. Older cameras and lenses–especially manual ones–often only work in full stops. And in situations with fast manual shooting or repetitive settings are required, using only full stops can be convenient. With video, having the smaller increments available can provide smoother transitions from one aperture to another. And some of the newer lenses, such as ones from Sony, have a switch that changes the manual aperture ring from being a smooth rotation with small aperture increments to a rotation that includes tactile clicks as you rotate–partly as a matter of preference and partly because the smoother rotation is better when shooting video (quieter and smoother).
mina says
hello. I have a question.In aperture i have two values: f/1.8 and f.8 . And now i want to delete “f” and convert these values without f. could you please me what is value for these two values without f?
thanks before your helping
David says
Not sure I follow what you’re asking. ƒ/8 f/8 f.8 and ƒ.8 all refer to the same thing, and the f simply indicates that it’s referring to the f-number of the aperture (technically, ratio of the lens’s focal length to the diameter of the opening). ƒ/8 is almost five stops from ƒ/1.8 (it’s four stops from ƒ/2 and five from ƒ/1.4).
Craig says
Hi
I am and amateur camera guy looking at getting in to the industry focusing on hi quality video work to the future
I currently have the Nikon D750 / Sony PWX-F7S (Which I am trying to learn) and looking for an Smaller camera more so for video. I am tired of watching comparisons and not understanding the full tech jargon
I am looking at the Sony A7III and Sony A7RIII with a FE35mm f1.8 lens for either camera – I would love to have you opinion
Any comments appreciated – Thank You
David says
You can’t go wrong with either of those two cameras–they’re both excellent. Their video features are pretty similar, although the a7R III does have a slight edge, as you’d expect with the more expensive model.
Another one worth considering if you’re focusing on video is the Panasonic GH5.