Canon RF50mm F1.8 STMvsTamron 17-70mm F/2.8 Di III-A VC RXD
RF50mm F1.8 STM
50mm / F1.8
—
17-70mm F/2.8 Di III-A VC RXD
17-70mm / F2.8
26-105mm equiv.
—
Which to choose
When the RF50mm F1.8 STM suits you better
- Brightness1.3 stops brighter — better in low light and blurs the background more
- Weight370g lighter, so easier to carry
When the 17-70mm F/2.8 Di III-A VC RXD suits you better
- Close focusFocuses as close as 19cm
- Zoom rangeCovers 17-70mm in a single lens
- StabilizationHas stabilization
- Weather sealingHas weather sealing
These points are derived mechanically from the numbers. How a lens actually renders does not show up in specifications, so look at samples before deciding.
Size compared
- RF50mm F1.8 STM40.5mm long × 69.2mm diameter
- 17-70mm F/2.8 Di III-A VC RXD117.3mm long × 74.6mm diameter
Specifications compared
| Specification | Canon RF50mm F1.8 STM | Tamron 17-70mm F/2.8 Di III-A VC RXD | Difference |
|---|---|---|---|
| Focal length (wide) | 50mm | 17mm | +33mm |
| Focal length (tele) | 50mm | 70mm | −20mm |
| Max aperture (wide) | F1.8 | F2.8 | 1.3 stops brighter |
| Max aperture (tele) | F1.8 | F2.8 | 1.3 stops brighter |
| Min aperture | F22 | — | No data |
| Min focus distance | 30cm | 19cm | +0.11m |
| Max magnification | 0.25× | — | No data |
| Aperture blades | 7blades | — | No data |
| Weight | 160g | 530g | −370g |
| Length | 40.5mm | 117.3mm | −76.8mm |
| Diameter | 69.2mm | 74.6mm | −5.4mm |
| Filter size | 43mm | 67mm | −24mm |
| Released | 2020 | 2026 | −6year |
| Stabilization | No | Yes | No |
| Weather sealing | No | Yes | No |
| Macro | No | No | — |
| Autofocus | Yes | Yes | — |
The difference column reads as RF50mm F1.8 STM relative to 17-70mm F/2.8 Di III-A VC RXD.The highlighted cell is the better side for that specification.
Check prices
RF50mm F1.8 STM
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17-70mm F/2.8 Di III-A VC RXD
ADLinks to Amazon, B&H Photo, Adorama, KEH Camera, MPB, eBay are affiliate links. We may earn a commission if you buy through them, at no extra cost to you.Links marked “Search results” go to that retailer’s search page for this lens name.Check price and availability on the retailer’s own site.
RF50mm F1.8 STM in detail17-70mm F/2.8 Di III-A VC RXD in detailAll RF mount lenses