Sigma 20mm F1.8 EX DG RF is a Fixed aperture Auto Focus (AF)
Ultra-Wideangle Prime lens with 35mm FF max sensor coverage, and it is designed to be used with
SA Mount cameras.
The Sigma 20mm F1.8 EX DG RF is also available in the Canon EF , Nikon F (DX), Pentax KAF and Sony Alpha mounts.
What type of photography is the Sigma 20mm F1.8 EX DG RF lens good for?
The choice of photography type for which you intend to use the Sigma 20mm F1.8 EX DG RF is a crucial decision factor. Below, we have assessed its suitability for various photography scenarios:
Reasons to Buy the Sigma 20mm F1.8 EX DG Aspherical RF Lens
Here we've included a summary of the advantages and disadvantages of the Sigma 20mm F1.8 EX DG Aspherical RF lens in a list form to assist you in determining whether it offers the features you need.
| Autofocus |
| Aperture Ring |
| Distance Scale |
| DoF(Depth of Field) Scale |
| Hood supplied |
| Full-time Manual Focusing |
| Fast Aperture |
| Covers Full-Frame Sensor |
| 9 Diaphragm Blades for Smooth Bokeh |
| Min focus distance of 0.2m / 7.9 inch |
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We couldn't find any significant Cons for the Sigma 20mm F1.8 EX DG Aspherical RF
Lens Mount
Sigma 20mm F1.8 EX DG RF is compatible with cameras that have a Sigma SA lens mount. Some of the latest released cameras that are compatible with the Sigma SA lenses are Sigma Quattro, Sigma Quattro H and Sigma SD1 Merrill.
Size, Weight and Filter Thread
The size and weight are crucial factors to consider when searching for your next lens. Sigma 20mm F1.8 EX DG RF has a maximum diameter of 89mm and a total length of 90mm. It weighs 520g / 18.3 oz.
Sigma 20mm F1.8 EX DG RF has a filter thread of 82mm. Below are links to the filters that we recommend you to consider for your Sigma 20mm F1.8 EX DG RF:
You can also check All Sigma SA Mount Lenses with 82mm Filter Thread Size to find the matching lenses.
Focal Range
Sigma 20mm F1.8 EX DG RF has a fixed focal length of 20mm.
Optical Image Stabilization
Sigma 20mm F1.8 EX DG RF doesn't have an optical image stabilization system so the only option to stabilize the image taken with this lens is to mount on a camera body with IBIS (sensor based In-body image stabilization).
Below are the 3 Ultra-Wideangle Prime type Sigma SA mount lens alternatives with highest max magnification ratios:
Aperture
The Sigma 20mm F1.8 EX DG Aspherical RF features a maximum aperture of F1.8 and can be stopped down to a minimum aperture of F22. With an exceptionally wide F1.8 maximum aperture, this lens excels in challenging low-light environments, letting you shoot at lower ISO speeds to keep images clean and noise-free. Given the wider 20mm field of view, the background will naturally stay a bit more in focus, making it ideal for environmental portraits, street photography, or landscapes where context matters. The minimum setting of F22 is excellent for deep depth of field work like macro photography, though you may want to avoid the absolute smallest settings to skip the sharpness loss caused by optical diffraction.
Optical Formula
Sigma 20mm F1.8 EX DG RF's optical formula consists of 13 elements in 11 groups . Special elements used in this design is 2 aspherical elements.
Lens Hood
Sigma 20mm F1.8 EX DG RF comes with a removable petal shaped lens hood which is handy to reduce lens flare and glare in your photos.
Body Colour
Sigma 20mm F1.8 EX DG RF is available in Black color.
Popular Comparisons of Sigma 20mm F1.8 EX DG RF
Here are the 8 most popular comparisons of the Sigma 20mm F1.8 EX DG RF amongst Camera Decision readers.
Top Alternatives of Sigma 20mm F1.8 EX DG RF Lens
In addition, it would be interesting to check which lenses from other mounts are most commonly compared with the Sigma 20mm F1.8 EX DG Aspherical RF.
Top Alternatives of Sigma 20mm F1.8 EX DG RF in Other Lens Mounts
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