Specifications#
- Brand
- Sigma
- Model
- 4.5mm f/2.8 EX DC HSM circular fisheye
- Lens type
- Fisheye
- Focal length
- 4.5 mm
- Maximum aperture
- f/2.8
- Image circle
- APS-C (23.5×15.6 mm)
- Mount(s)
- Canon EF, Nikon F, Sony / Minolta A-mount, Pentax K, Sigma SA
- Projection
- Fisheye
- Autofocus motor
- hypersonic (HSM)
- 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 4.5 mm | Equiv. aperture (DoF) |
|---|---|---|
| APS-C | 7 mm · 145° | f/4.2 |
| APS-C (Canon) | 7 mm · 143° | f/4.5 |
| Micro Four Thirds | 9 mm · 135° | 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: 14 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 |
|---|---|---|---|---|---|---|---|
| 4.5 mm | f/2.8 | ∞ | ∞ | ∞ | ∞ | 37.4 cm | 0.0% |
| 4.5 mm | f/4 | ∞ | ∞ | ∞ | ∞ | 26.3 cm | 0.0% |
| 4.5 mm | f/8 | ∞ | ∞ | ∞ | ∞ | 13.4 cm | 0.0% |
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 4.5 mm | NPF at 4.5 mm, f/2.8 |
|---|---|---|---|
| APS-C | 1/6 s | 74 s | 48 s |
| APS-C (Canon) | 1/8 s | 69 s | 46 s |
| Micro Four Thirds | 1/10 s | 56 s | 44 s |
Compatible cameras#
Bodies in our database with a native Canon EF, Nikon F, Sony / Minolta A-mount, Pentax K and Sigma SA 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
- Canon EOS 6D Mark II crop mode
- Nikon D7500 2017
- Nikon D850 crop mode
- Nikon D5600 2016
- Ricoh Pentax K-1 crop mode
- Canon EOS 5D Mark IV crop mode
- Canon EOS-1D X Mark II crop mode
- Nikon D3400 2016
- Nikon D500 2016
- Ricoh Pentax K-70 2016
- Nikon D5 crop mode
- Ricoh Pentax K-3 II 2015
- Canon EOS 5DS crop mode
- Nikon D5500 2015
- Nikon D7200 2015
- Canon EOS 5DS R crop mode
- Sony Alpha 77 II 2014
- Nikon D4S crop mode
- Nikon D750 crop mode
- Nikon D810 crop mode
- Nikon D3300 2014
- Nikon D7100 2013
- Sony Alpha 58 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
- Canon EOS 5D Mark III crop mode
- Canon EOS 6D crop mode
- Canon EOS-1D X crop mode
Adapt it to other systems#
Similar lenses#
Frequently asked questions#
Is the Sigma 4.5mm f/2.8 EX DC HSM circular fisheye 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 4.5mm f/2.8 EX DC HSM circular fisheye equivalent to on APS-C?
Its focal length is already the real value for APS-C: 4.5 mm frames like 7 mm on full frame.
What is the Sigma 4.5mm f/2.8 EX DC HSM circular fisheye good for?
As a fisheye it suits creative ultra-wide views, skateboarding, interiors and all-sky astro.
Sources & licences#
- Lensfun lens database — CC BY-SA 3.0
Last updated October 03, 2026 · How we calculate · Sources