Can these lens be 'twisted' to 'zoom'?

King Mustard · Apr 15, 2020

In 2016, I bought a Nikon D3300 + Nikon AF-P DX NIKKOR 18-55mm f/3.5-5.6G VR lens (£275) (sold in 2019 for £180).

I don't know much about cameras, but I know that when I 'twisted' the lens, the lens, for all intents and purposes, 'zoomed'.

I was considering buying a mirrorless camera to replace it - mainly because of their smaller footprint (DSLRs are too bulky to take abroad with me).

Some example mirrorless camera kits I'd end up getting are:

1. Can each of these lens be 'zoomed' (I'm fully aware it's the incorrect term) like my previous D3300 one could?
2. If not, what should I look out for to make sure they can? Do I just make sure they don't have 'prime' in the title/description?
3. If they can, do you think the 'zoom' amount is roughly the same? (I think the lens on my D3300 was roughly equivalent to 3x)

480sparky · Apr 15, 2020

If you're not sure what 'zoomed' means, how do you know the lens zoomed?

If you turn the zoom ring, you will change the focal length. That's what zoom lenses are supposed to do.

Any time a range of focal lenths are listed on a lens, it's a zoom (18-55, 12-32, 16-50....).

King Mustard · Apr 15, 2020

480sparky said:
If you're not sure what 'zoomed' means, how do you know the lens zoomed?

If you turn the zoom ring, you will change the focal length. That's what zoom lenses are supposed to do.

Any time a range of focal lenths are listed on a lens, it's a zoom (18-55, 12-32, 16-50....).

Focal length, that's the one. I know it's frowned upon to call it 'zoom'. However, to me, if twisting the lens ring 'gets me closer' in the viewfinder, it has zoomed

Thank you for your help

480sparky · Apr 15, 2020

King Mustard said:
...... I know it's frowned upon to call it 'zoom'. .......

It's a very common term.

King Mustard · Apr 15, 2020

It appears that my D3300 came with a 18-55mm lens.

The example mirrorless cameras I listed above come with either a 12-32mm, 14-42mm or 16-50mm lenses.

I don't really understand what they mean but if I was happy with my 18-55mm lens, I presume I should aim to get the 16-50mm lens (as it's the closest)?

480sparky · Apr 15, 2020

Focal length is only one variable in the equation. The other is the size of the sensor. Three of the cameras you listed are micro 4/3, the Sony is a APS-C.

King Mustard · Apr 15, 2020

480sparky said:
Focal length is only one variable in the equation. The other is the size of the sensor. Three of the cameras you listed are micro 4/3, the Sony is a APS-C.

How does it affect the "zoom"?

480sparky · Apr 15, 2020

King Mustard said:
480sparky said:

Focal length is only one variable in the equation. The other is the size of the sensor. Three of the cameras you listed are micro 4/3, the Sony is a APS-C.

Click to expand...

How does it affect the "zoom"?

"Zoom" simply means the focal length of the lens is adjustable. You can 'zoom out' for a wide field of view, or 'zoom in' for a narrower on. All 4 camera you list will have roughly the same field of view since they have different sensor sizes.

VidThreeNorth · Apr 15, 2020

All the lenses that you mentioned have a zoom ring on the lens that can be twisted to zoom. The Sony 16-50 lens is a "power zoom" lens. For that camera and lens combination you can manually "twist" the zoom ring, but it also has electronically controlled zoom switches on the lens and also on the body which can control the lens. I have that same lens on my Sony a5000 (a slightly older and cheaper model than the a5100). Because I don't have any other "power zoom" lenses, I have to "twist" the zoom ring on all my other zoom lenses. And because of this, I mainly use the "zoom ring" when I use that lens -- as a matter of habit.

Designer · Apr 15, 2020

King Mustard said:
I know it's frowned upon to call it 'zoom'.

Not around here, it isn't. That is the normal term for a zoom lens, and we use it all the time.

Derrel · Apr 15, 2020

The ones you listed all zoom.

ac12 · Apr 15, 2020

Simple math.

For zoom ratio.
Divide the large number by the small number to get the zoom ratio.
Example 18-55. 55/18=3.1x

Magnification or lens viewing angle depends on the sensor size.
The easy method is magnification.
m4/3 has a 25mm normal lens, APS-C has a 35mm normal lens.
You have to know the sensor size to make this work. But that is usually easy to fing.
Divide the lens focal length by the normal lens for that sensor, to get the magnification.
APSC = 35; 18-55 = 18/35 and 55/35 = 0.5 - 1.6x
m4/3 = 25, 12-32 = 12/25 and 32/25 = 0.5 - 1.3x

480sparky · Apr 16, 2020

ac12 said:
Simple math.

For zoom ratio.
Divide the large number by the small number to get the zoom ratio.
Example 18-55. 55/18=3.1x

Magnification or lens viewing angle depends on the sensor size.
The easy method is magnification.
m4/3 has a 25mm normal lens, APS-C has a 35mm normal lens.
You have to know the sensor size to make this work. But that is usually easy to fing.
Divide the lens focal length by the normal lens for that sensor, to get the magnification.
APSC = 35; 18-55 = 18/35 and 55/35 = 0.5 - 1.6x
m4/3 = 25, 12-32 = 12/25 and 32/25 = 0.5 - 1.3x

The diagonal measurement of the sensor will give you the 'normal' focal length.

Full frame 36x24: √(36² + 24²) = 43.267
APS-C 24x18 : √(24² + 18²) = 32.863.
µ4/3 = √(17.3² + 13²) = 21.64.

Derrel · Apr 16, 2020

Go read some online reviews of the cameras you are considering buying. The reviews will tell you what it is like to use them. Cameras these days are so good that they are typically better than users.