What do the numbers on lenses mean?
- Thread starter Sarah8914
- Start date
I'm honestly the last person that should be answering a question like that, but here's what I know: when there's one number it means it's a prime lens and won't zoom. It's fixed. It's usually a better quality lens for the price, though. A 35mm will be farther back than a 50mm (you'll get more people in the picture). Someone will correct me if I'm wrong, I'm sure, but that's just what I understand! Good luck!
aggiefamily
New member
I wouldn't say it is better but different. Some people like it because it is easier to use manual (focus) on a fixed lens. I personally like a zoom lens better and have more luck with it than my fixed.
ColleenSwerb
Brodo gettin her Swerb on
That's where a second set of numbers come into play Sarah. Such as 50mm f/1.8 or f/1.4 vs an 18-55mm f/3.5-5.6. There are also zooms wtih fixed apertures, such as my 28-75mm f/2.8.
The numbers after the f represent the aperture. When you click the button to take a picture, a series of pieces of plastic open up in front of the sensor to create a hole for light to enter (the light is what creates the picture). The smaller the f number, the BIGGER the hole is. This ties into shutter speed when determining the proper exposure, but that's a whole other can of worms, lol.
So the aperture = the hole. An f/1.4 is a far bigger hole than a f/3.5, even though they seem close together (there's a ratio, but I forget what it is and I don't want to give bad info). This means that there is a much greater opportunity for light to reach your camera sensor. "Prime" lenses (fixed length, such as only 50mm) are also fixed aperature. This is important in low light situations (such as shooting indoors in winter), because the bigger hole means a better chance for light to get through the hole.
So something like your kit lens have a whole mess o' numbers. 18-55mm f/3.5-5.6. So you can shoot at varying lengths from 18-55 (you can zoom). But, it does not have a fixed aperture. So when you're at 18mm, the biggest hole you can make is 3.5. But when you go up to 55mm, the biggest hole is only at 5.6. That's a big difference in the size of the hole. Plus, 3.5 is not big compared to a 1.4/1.8/2.0 etc.
Zoom lenses with a fixed aperture (like my Tamron brand 28-75 f/2.8) are far more expensive than regular zooms because it takes a LOT more work to make the 2.8 available to all focal lengths (apparently, I don't really know why though, LOL!). The Nikon 25-70mm f/2.8 costs $1500. :blink: Lol!
Sooo I probably just confused the heck out of you. It is widely considered that prime lenses are sharper than zoom lenses, but that's not really the case anymore. Technology has come FAR in that sense. Prime lenses also offer better low light capabilities, which is why a lot of people like them.
Sorry for rambling! I tried to explain it as simply as I could....
The numbers after the f represent the aperture. When you click the button to take a picture, a series of pieces of plastic open up in front of the sensor to create a hole for light to enter (the light is what creates the picture). The smaller the f number, the BIGGER the hole is. This ties into shutter speed when determining the proper exposure, but that's a whole other can of worms, lol.
So the aperture = the hole. An f/1.4 is a far bigger hole than a f/3.5, even though they seem close together (there's a ratio, but I forget what it is and I don't want to give bad info). This means that there is a much greater opportunity for light to reach your camera sensor. "Prime" lenses (fixed length, such as only 50mm) are also fixed aperature. This is important in low light situations (such as shooting indoors in winter), because the bigger hole means a better chance for light to get through the hole.
So something like your kit lens have a whole mess o' numbers. 18-55mm f/3.5-5.6. So you can shoot at varying lengths from 18-55 (you can zoom). But, it does not have a fixed aperture. So when you're at 18mm, the biggest hole you can make is 3.5. But when you go up to 55mm, the biggest hole is only at 5.6. That's a big difference in the size of the hole. Plus, 3.5 is not big compared to a 1.4/1.8/2.0 etc.
Zoom lenses with a fixed aperture (like my Tamron brand 28-75 f/2.8) are far more expensive than regular zooms because it takes a LOT more work to make the 2.8 available to all focal lengths (apparently, I don't really know why though, LOL!). The Nikon 25-70mm f/2.8 costs $1500. :blink: Lol!
Sooo I probably just confused the heck out of you. It is widely considered that prime lenses are sharper than zoom lenses, but that's not really the case anymore. Technology has come FAR in that sense. Prime lenses also offer better low light capabilities, which is why a lot of people like them.
Sorry for rambling! I tried to explain it as simply as I could....
nesser1981
Sweet Shoppe SugarBabe
Another thing to consider about the cheaper lenses is that they are made with plastic, not glass.
I have a 30mm 1.4 and it is heavier than my 70-300mm (which is really cheap, but bigger).
And for example, I had the 50mm 1.8 and it was tiny, my 30 is almost twice the size because its built better. You are honestly paying for what you get.
All of my photography teachers have been telling us invest in lenses, don't worry about the camera body so much.
I have a 30mm 1.4 and it is heavier than my 70-300mm (which is really cheap, but bigger).
And for example, I had the 50mm 1.8 and it was tiny, my 30 is almost twice the size because its built better. You are honestly paying for what you get.
All of my photography teachers have been telling us invest in lenses, don't worry about the camera body so much.
Megan Turnidge
New member
Well, if you get a really good prime compared to a zoom... generally I've been told that primes are a little sharper. But honestly, I think it's mostly a preference thing... I prefer primes.
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thanks everyone.
Col, you made perfect sense. I actually usually shoot in aperature mode and know a *little* about it... but I didn't understand why it was 3.5-5.6, and now I do! And, I didn't make the connection to low light situations, which would be ideal for me in our house! It's not bright enough anywhere and I always shoot in auto inside.
seriously, thanks guys, this info is perfect!
Col, you made perfect sense. I actually usually shoot in aperature mode and know a *little* about it... but I didn't understand why it was 3.5-5.6, and now I do! And, I didn't make the connection to low light situations, which would be ideal for me in our house! It's not bright enough anywhere and I always shoot in auto inside.
seriously, thanks guys, this info is perfect!