IRIX Blackstone 11mm f/4
The 11mm focal length, constant f/4 aperture, and advanced optic layout with three aspherical and two ED elements ensure sharp, rectilinear images free of distortion, housed in a weather-sealed magnesium alloy body. A manual focus mechanism includes a focus lock, UV fluorescent engraved markings, and a rounded nine-blade diaphragm for precise control and smooth bokeh. This lens suits architectural and interior photographers who demand a rugged, weather-resistant ultra-wide prime for detailed, field-based work.
Snapshot
Pros & Cons
Pros
- Strong optical (88th percentile) 88th
- Strong macro (73rd percentile) 73rd
Cons
- Below average user sentiment (11th percentile)
- Below average af (15th percentile)
- Below average build (20th percentile)
- Below average aperture (24th percentile)
What owners think
How owner sentiment changed over time
ExclusiveBased on when customers actually wrote their reviews - so you can see whether early praise held up.
Based on 21 dated customer reviews, grouped by calendar quarter. Period analysis is in English.
The proof
Performance
Specifications
Full Specifications
Optics
| Type | Wide-angle |
| Focal Length Min | 11 |
| Focal Length Max | 11 |
| Elements | 16 |
| Groups | 10 |
| Aspherical Elements | 3 |
| ED Elements | 2 |
| Coating | Neutrino coating |
Aperture
| Max Aperture | f/22 |
| Min Aperture | f/4 |
| Constant | Yes |
| Diaphragm Blades | 9 |
Build
| Mount | Pentax K |
| Format | full-frame |
| Weather Sealed | Yes |
| Weight | 0.8 kg / 1.7 lbs |
AF & Stabilization
| AF Type | Manual Focus |
| Stabilization | No |
Focus
| Min Focus Distance | 275 |
vs Competition
| Spec | IRIX Blackstone 11mm f/4 | Sigma Contemporary 16-300mm f/3.5-6.7 DC OS | Tamron Di III 18-300mm f/3.5-6.3 Di III-A VC VXD | Canon RF 28-70mm f/2.8 IS STM | Panasonic LUMIX S S-R28200 | Nikon NIKKOR AF-S DX NIKKOR 16-85mm f/3.5-5.6G ED VR |
|---|---|---|---|---|---|---|
| Focal Length | 11mm | 16-300mm | 18-300mm | 28-70mm | 28-200mm | 16-85mm |
| Max Aperture | f/22 | f/3.5 | f/3.5 | f/2.8 | f/4 | f/3.5 |
| Mount | Pentax K | Sony E | Fujifilm X | Canon RF | L-Mount | Nikon F |
| Stabilization | false | true | true | true | true | true |
| Weather Sealed | true | true | false | true | true | false |
| Weight (g) | 790 | 615 | 92 | 495 | 413 | 59 |
| AF Type | Manual Focus | HLA | VXD linear motor | STM | Autofocus | AF-S |
| Lens Type | wide-angle | zoom | zoom | zoom | macro | zoom |
| Compare | Compare | Compare | Compare | Compare |
| Product | AF | Bokeh | Build | Macro | Optical | Aperture | User Sentiment | Versatility | Social Proof | Stabilization |
|---|---|---|---|---|---|---|---|---|---|---|
| IRIX Blackstone 11mm f/4 | 15.2 | 27.7 | 20.3 | 72.5 | 88 | 24 | 11.3 | 34.1 | 55.4 | 35.6 |
| Sigma Contemporary 16-300mm f/3.5-6.7 DC OS Compare | 54.6 | 84 | 57.8 | 86.5 | 98.8 | 76.8 | 0 | 99.6 | 83.1 | 99.1 |
| Tamron Di III 18-300mm f/3.5-6.3 Di III-A VC VXD Compare | 98.1 | 74.8 | 96.3 | 88.4 | 73.5 | 76.8 | 34.5 | 99.2 | 83.1 | 80.5 |
| Canon RF 28-70mm f/2.8 IS STM Compare | 85.4 | 86 | 67.2 | 77.3 | 84.4 | 83.7 | 0 | 77.5 | 88 | 98.3 |
| Panasonic LUMIX S S-R28200 Compare | 54.6 | 77.7 | 73.8 | 89.5 | 90.9 | 71.2 | 0 | 95.6 | 75.4 | 99.4 |
| Nikon NIKKOR AF-S DX NIKKOR 16-85mm f/3.5-5.6G ED VR Compare | 54.6 | 74.8 | 98.4 | 59.7 | 64.1 | 76.8 | 83.3 | 94.3 | 88 | 92.2 |
Price
Value & Pricing
B&H Photo 1 offer From CA$579
We started tracking prices for this product on Jun 3, 2026. The chart appears once we have more data.
Usage Scores
A full written review is coming soon. The specs, scores, prices and charts above are always up to date.
