The Ricoh GR III has a fixed 18mm prime lens. 1 On the GR III’s APS-C sensor, that’s the equivalent of around a 28mm focal length of a full-frame (35mm) camera. So it’s a medium-wide perspective.
While you can’t switch out the lens on the GR III—it’s fixed—there is a way to get a wider perspective. Ricoh makes a dedicated wide-angle conversion lens that clips onto the front of the camera. A few years ago, I reviewed the previous model for the GR II.
There’s a new model just for the GR III—it’s the GW-4 0.75 Wide Conversion Lens.

This lens clips onto the front of the camera. It’s basically a hunk of glass—there’s no aperture, focusing, or other controls on the lens itself. You can often pick up conceptually similar lenses billed as wide-angle lenses very cheaply, and they’re often pretty terrible. But don’t let that put you off—Ricoh has made sure that this model is several steps up from those in quality. And, frankly, it’d want to be if only because it’s not cheap. Ricoh has set the MSRP at $250, and then you’ll need to spend another $50 on top of that for the adapter ring. So all up, you’re looking at $300. This is not a lot for a good lens, but it is quite a lot for a lens like this that is just solid glass.
- For GR III Digital Camera
- Provides 21mm Equivalent Focal Length
- Magnification: 0.75x
- Requires GA-1 Adapter for Use (not included)
- Required for GW-4 Wide Conversion Lens
It takes the camera’s standard 28mm perspective to a significantly wider 21mm perspective. I have some examples below on what that translates to in visual terms.
Pros
- Surprisingly good optics
- Useful wide focal length if you like wide-angle perspective
- Reasonably priced
Cons
- Adds significant bulk and weight compared to the size of the camera
- Have to buy the GA-1 adapter separately
It just clips on the front of the camera. It adds quite a bit of size and weight to the GR III, so you’re probably not going to be able to just slip the camera into your pocket anymore. To switch between the 28mm and 21mm perspectives, you remove the lens; there’s not a more convenient way to switch between them.
I’ve been pleasantly surprised at the quality. Adding a thick layer of glass to the lens will undoubtedly have an effect—and typically a negative one—but the engineers at Ricoh have done a good job with this lens to make sure that the negative effects are minimized. The quality remains very good, and there’s a minimal amount of light dropoff. There’s not much in the way of lens distortion or bowing, the edges and corners are still quite sharp, and there’s not much in the way of chromatic aberration (purple fringing). I’ve included some practical examples below.
Table of Contents
Essential Accessory: Ricoh GA-1 Lens Adapter
If you’re going to buy the GW-4, make sure you also buy the GA-1 lens adapter as well. You won’t be able to use the GW-4 lens without it.

The GW-4 is a lightweight plastic adapter barrel. It contains no glass and has only minimal electronics. It’s a multipurpose adapter in that it includes a traditional 49mm diameter filter thread (but a plastic one, so it’s not as robust as a metal film thread), so you can use it to attach regular screw-on filters (ideally, use 49mm ones, or you can use a step-up or step-down adapter.

I don’t understand why Ricoh doesn’t include it with the GW-4. By all means, offer it as a separate accessory if you want—after all, it works with other Ricoh lenses, and it’s a common way to add filters to cameras like the Ricoh GR-III—but the GW-4 can’t work without it. It’s also overpriced—$50 for what is mostly some flimsy, lightweight plastic.

21mm vs 28mm on the Ricoh GR III / With and Without GW-4 Wide-Angle Conversion Lens
Here are some side-by-side examples without and with the GW-4 lens.








Photos Taken with the GW-4 Wide-Angle Lens on Ricoh GR III
Here are some real-world examples. These were all taken with the GR III and the GW-4 (and the GA-1, of course). They were shot in RAW (.dng). I’ve processed them in Lightroom, but I haven’t applied any of Lightroom’s sharpening, lens distortion, or chromatic aberration fixes.
You can click on each image for a full-size version for a closer look.














Things Worth Knowing About the Ricoh GW-4 Wide-Angle Lens Adapter
The front of the lens has a screw-on filter thread. It’s a 72mm diameter, so you can use standard 72mm screw-on filters or a step-up/step-down ring. You can leave the rubber lens hood on, although it makes operating a circular polarizer difficult and gets in the way with a step-up ring.
Key Specifications
Model | GW-4 |
---|---|
Compatibility | For Ricoh GR III camera. Requires Ricoh GA-1 lens adapter. (NB. The GA-1 is sold separately) |
Magnification | 0.75x. On Ricoh GR III, it comes to around 21mm focal length (35mm equivalent). |
Angle of View | Approx. 90 degrees (diagonal) |
Lens Construction | 4 elements in 3 groups |
Weight | Approx. 8.5 oz / 256 grams |
Filter Diameter | 72mm |
Filter Type | Screw-on threaded |
Lens Hood | Soft rubber slip-on lens hood included. |
Zoom? | No. It’s fixed magnification. |
Autofocus Compatible? | Yes. Focusing is handled by the GR III’s built-in lens as normal. |
Manual Focus Ring? | No. Focusing is handled by the GR III’s built-in lens. |
Aperture Ring? | No. Aperture is handled by the usual in-camera controls. |
Model | GA-1 |
---|---|
Compatibility | For Ricoh GR III camera. Required for using GW-4 Wide-Angle Lens. |
Filter Size | 49mm |
Filter Type | Screw-on threaded |
Weight | 0.4 ounces / 11 grams |
Price & Availability of Ricoh GW-4 Wide Conversion Lens
When I bought mine, the GW-4 was a new product. Since then, they’ve been turning up on the used market as well, so I’ve included some good places to try below.
But wherever you buy it, don’t forget that you need to get the GA-1 lens adapter as well.
Buy New
I’ve actually bought two of these over the course of a few years. I bought one at Amazon and the other at B&H Photo.
- For GR III Digital Camera
- Provides 21mm Equivalent Focal Length
- Magnification: 0.75x
- Requires GA-1 Adapter for Use (not included)
- Required for GW-4 Wide Conversion Lens
Buy Used
Some good places to try for used copies of the GW-4 include:
Related Posts
- The focal length self-reports in the EXIF information as 18.3mm.[↩]
Images and product information from Amazon PA-API were last updated on 2023-09-27 at 13:16. Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon Site at the time of purchase will apply to the purchase of this product.
Ricoh GR III Accessories & Replacement Parts
Here are the model numbers of some of the core accessories and replacement parts for the Ricoh GR III.
Ring Cap
- Ring Cap: GN-1
The ring cap is the small plastic ring that attaches around the lens. Chances are, it’s fallen off. While you do have to remove it to attach the lens adapter, it’s a poor design that tends to fall off and get lost far too often. I’ve lost a couple of them now.
The camera will work just fine without it. But that will leave some contacts exposed around the lens barrel, which isn’t ideal.
The official replacement part is overpriced. But you can also pick up much less expensive aftermarket versions. They’re also available in different colors, so you can bling up your camera with a personal touch—or make it look like the Street Edition.
- 【Compatibility】: Designed for Ricoh GRIII (only).This decoration ring is made of high quality...
- 【Easy to use & Protector】:Easy installation and removal and Protects lens barrel exterior.
USB Cable
The GR III has a USB Type-C connector port. When you get a cable, you can get them with another USB Type-C connector on the other end or a more traditional USB Type-A connector. Which you choose depends entirely on what you’re plugging into. For example, some newer laptops only have USB-C, while most other computers have USB-A.
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- Enhanced Durability: Improved construction techniques and materials make a cable that lasts 12× longer.
Battery & Charger
- Battery: DB-110
It’s a rechargeable lithium-ion battery rated at 3.6V 1350mAh 4.9Wh.
There are some other cameras that also use the same battery—notably, some Olympus cameras (the Olympus model number for the same battery is LI-90B). So they’re quite widely available. You can get the official Ricoh version. There are also aftermarket versions that can be much better value but work just as well.
- COMPATIBILITY - Works with these popular Ricoh cameras that use DB110 batteries: Ricoh GR III, Ricoh GR...
- BATTERY & CHARGER SPECS - Premium Grade-A cells rated at 3.7V, 1300mAh for longer run-time and battery...
- Charger: BJ-11
You can charge the battery in the camera (using a USB-C cable). There are also external battery chargers available. They’re especially useful if you’re using spare batteries, so you can charge and shoot simultaneously.
- AC Adapter: K-AC166
This is used to power the camera for longer shoots, such as time-lapse, or if you happen to be using the camera for live streaming as a webcam. It connects via the camera’s USB-C port.
Wide-Angle Conversion Lens
Ricoh has produced a wide-angle conversion lens that takes the standard 28mm view down to a 21mm (in 35mm equivalent). While it does add some extra bulk to an otherwise small camera, it works well and adds a more dramatic, wider view. I have an in-depth review of it separately.
Something to be aware of, though, is that you will also need to pick up the lens adapter separately. For reasons I really don’t understand, the wide-angle conversion lens doesn’t come with the adapter, and both are required to make it work. So make sure you pick up one of those at the same time.
Remote Shutter Releases
- Wired Shutter Release: CA-3
This is the official Ricoh remote shutter. It connects to the camera via a USB cable, and it’s a simple shutter release (i.e., there’s no timer or intervalometer).
You can also find aftermarket shutter releases for the GR III.
- Easy to operate, Half-press to focus, Full-press to shoot
- Fits macro photography well, eliminates camera shake
External Viewfinders
- Standard External Viewfinder: GV-1
- Mini External Viewfinder: GB-2
The Ricoh GR III doesn’t have a built-in viewfinder. But they make two versions of an external viewfinder that slides into the camera’s hot shoe. It covers both the standard 28mm view as well as the 21mm view if you’re using the wide-angle conversion lens. There’s also a mini viewfinder; that model seems to be hard to find.
Screen Protector
The back screen of the GR III is quite exposed, and if you lie the camera on its back, the screen comes in contact with the surface. Even if you’re putting the camera in your pocket, there’s a risk of keys or coins scratching the screen.
There’s no official screen protector, but there are good aftermarket versions. The one I use is this one. It’s essentially a consumable that protects the screen. If you scratch the protector, you can quickly and easily replace it with another from the pack.
- ✪LCD Screen Protector perfectly fit for Ricoh GR 3 DSLR Camera . Not for other model. Easy to install...
- ✪9H Hardness - Longer tempering time, which made the screen protector has a higher hardness. Prevents...
Carrying
- Soft Case: GC-9
You can, of course, use the GR III with just about any camera case or bag. But Ricoh does make a dedicated soft-case that fits snugly around the camera and offers some protection even if you’re toting the camera around in your pocket. I’ve been using one for a couple of years, and it’s held up very well, and it keeps my camera safer from bumps and scratches.
- Neck Strap: GS-3
Again, there’s no particular reason you have to use the official GR neck strap, but there is one. The main part is leather, and it even has a discreet, embossed "GR".
If you do use a different strap, be aware that the strap loops on the camera are very small and won’t take thicker (i.e., stronger) attachment loops. So you might need to use some D-rings as well.
- Hand Strap: GS-2
There’s even an official "GR" leather hand strap! But, again, aside from the branding, there’s no special reason to use the official strap. If you do use a different one, you might need D-rings if the thread doesn’t go through the camera’s small attachment loops.
External Flash
The GR III doesn’t have a built-in flash. It supports the Pentax P-TTL flash protocol.
Pentax External Flashes: