Specifications#
- Brand
- Sigma
- Model
- 18-50mm f/2.8 EX DC
- Lens type
- Standard zoom
- Focal length
- 18–50 mm
- Maximum aperture
- f/2.8
- Image circle
- APS-C (23.5×15.6 mm)
- Projection
- Rectilinear
- Lensfun correction profile
- Yes — distortion/vignetting/TCA
Equivalent focal length on different cameras#
Field of view and depth-of-field equivalence when this lens is used on bodies with different sensor sizes (natively or via an adapter).
| Camera format | At 18 mm | At 30 mm | At 50 mm | Equiv. aperture (DoF) |
|---|---|---|---|---|
| APS-C | 27 mm · 76° | 45 mm · 50° | 75 mm · 32° | f/4.2 |
| APS-C (Canon) | 29 mm · 73° | 48 mm · 48° | 80 mm · 30° | f/4.5 |
| Micro Four Thirds | 36 mm · 62° | 60 mm · 40° | 100 mm · 24° | f/5.6 |
Depth of field & background blur#
Computed on its native APS-C format (CoC 20 µm). “Blur @2 m” is the size of an out-of-focus point at infinity, as a percentage of frame width, with the subject at 2 m — a simple bokeh index. Full table: 20 mm f/2.8 on aps-c.
| Focal | Aperture | at 1 m | at 2 m | at 5 m | at 10 m | Hyperfocal | Blur @2 m |
|---|---|---|---|---|---|---|---|
| 18 mm | f/2.8 | 34.1 cm | 1.51 m | 28.9 m | ∞ | 5.93 m | 0.2% |
| 18 mm | f/4 | 50.2 cm | 2.48 m | ∞ | ∞ | 4.16 m | 0.2% |
| 18 mm | f/8 | 1.22 m | 45.6 m | ∞ | ∞ | 2.09 m | 0.1% |
| 30 mm | f/2.8 | 11.8 cm | 48.6 cm | 3.33 m | 19.2 m | 16.5 m | 0.7% |
| 30 mm | f/4 | 17.0 cm | 70.6 cm | 5.31 m | 69.6 m | 11.5 m | 0.5% |
| 30 mm | f/8 | 34.7 cm | 1.55 m | 34.1 m | ∞ | 5.78 m | 0.2% |
| 50 mm | f/2.8 | 4.2 cm | 17.1 cm | 1.10 m | 4.58 m | 45.7 m | 1.9% |
| 50 mm | f/4 | 6.0 cm | 24.5 cm | 1.59 m | 6.90 m | 32.0 m | 1.4% |
| 50 mm | f/8 | 11.9 cm | 49.6 cm | 3.43 m | 20.3 m | 16.0 m | 0.7% |
Handheld & night-sky limits#
NPF assumes typical 20–24 MP sensors (≈6 µm pixels on full frame, ≈3.9 µm on APS-C, ≈3.3 µm on Micro Four Thirds).
| Body | Min. handheld shutter (longest focal) | 500 rule at 18 mm | NPF at 18 mm, f/2.8 |
|---|---|---|---|
| APS-C | 1/80 s | 19 s | 12 s |
| APS-C (Canon) | 1/80 s | 17 s | 12 s |
| Micro Four Thirds | 1/100 s | 14 s | 11 s |
Compatible cameras#
Bodies in our database with a native Sigma SA, Nikon F, Pentax K and Canon EF mount. Full-frame bodies switch to an APS-C crop with this lens.
- Ricoh Pentax KF 2022
- Ricoh Pentax K-3 Mark III 2021
- Nikon D6 crop mode
- Nikon D780 crop mode
- Canon EOS-1D X Mark III crop mode
- Nikon D3500 2018
- Pentax K-1 II crop mode
- Ricoh Pentax KP 2017
- Nikon D7500 2017
- Nikon D850 crop mode
- Canon EOS 6D Mark II crop mode
- Nikon D5600 2016
- Ricoh Pentax K-1 crop mode
- Nikon D3400 2016
- Nikon D500 2016
- Ricoh Pentax K-70 2016
- Canon EOS 5D Mark IV crop mode
- Canon EOS-1D X Mark II crop mode
- Nikon D5 crop mode
- Ricoh Pentax K-3 II 2015
- Nikon D5500 2015
- Nikon D7200 2015
- Canon EOS 5DS crop mode
- Canon EOS 5DS R crop mode
- Nikon D4S crop mode
- Nikon D750 crop mode
- Nikon D810 crop mode
- Nikon D3300 2014
- Nikon D7100 2013
- Pentax K-3 2013
- Nikon D5300 2013
- Nikon D610 crop mode
- Nikon Df crop mode
- Pentax K-50 2013
- Blackmagic Design Pocket Cinema Camera crop mode
- Nikon D3200 2012
- Nikon D4 crop mode
- Nikon D5200 2012
- Nikon D600 crop mode
- Nikon D800 crop mode
Adapt it to other systems#
Similar lenses#
- Nikon Nikkor AF-P 18-55mm f/3.5-5.6G DX VR f/3.5–5.6
- Nikon Nikkor AF-S 18-105mm f/3.5-5.6G DX ED VR f/3.5–5.6
- Nikon Nikkor AF-S 18-55mm f/3.5-5.6G DX ED f/3.5–5.6
- Nikon Nikkor AF-S 18-55mm f/3.5-5.6G DX VR f/3.5–5.6
- Nikon Nikkor AF-S 18-55mm f/3.5-5.6G DX VR II f/3.5–5.6
- Nikon Nikkor AF-S 18-70mm f/3.5-4.5G DX IF-ED f/3.5–4.5
- Pentax HD Pentax-DA 18-50mm f/4-5.6 DC WR RE f/4–5.6
- Pentax smc Pentax-DA 18-55mm f/3.5-5.6 AL f/3.5–5.6
- Pentax smc Pentax-DA 18-55mm f/3.5-5.6 AL II/L/WR f/3.5–5.6
- Pentax smc Pentax-DA L 18-50mm f/4-5.6 DC WR RE f/4–5.6
- Sigma 18-125mm f/3.5-5.6 DC f/3.5–5.6
- Sigma 18-35mm f/1.8 DC HSM [A] f/1.8
Frequently asked questions#
Is the Sigma 18-50mm f/2.8 EX DC full frame?
No — it is designed for APS-C sensors. On a full-frame body it vignettes or triggers crop mode.
What is the Sigma 18-50mm f/2.8 EX DC equivalent to on APS-C?
Its focal length is already the real value for APS-C: 18–50 mm frames like 28–77 mm on full frame.
What is the Sigma 18-50mm f/2.8 EX DC good for?
As a standard zoom it suits everyday shooting, travel, events and walkaround use.
Sources & licences#
- Lensfun lens database — CC BY-SA 3.0
Last updated October 03, 2026 · How we calculate · Sources