Raynox DCR-720 wide converter

Search eBay for Raynox wide angle converter suitable for compact cameras.

Introduction

Unlike DSLR cameras, compact digital cameras have non-detachable lenses. While you can get (almost) any focal length you want on a DSLR simply by replacing its lens with another, the focal lengths available on a compact camera is initially determined by the zoom range of its non-detachable lens.

There is one remedy. By fitting an additional lens in front of the existing, its focal length range of the primary zoom can be (to some extent) be converted to a different range.

Converter lenses are not labeled with a focal length. Instead, they are designated by a conversion factor. Wide angle converters have a conversion factor less than 1 (e.g. 0.72x). Tele converters have a conversion factor greater than 1 (e.g. 2x).

The idea is that you multiply the focal length you set on your cameras primary lens with the conversion factor to find the combined focal length of the primary and secondary lens. For instance, if your primary lens is 7.2 mm, and the conversion factor is 0.72x, the resulting focal length when the converter is attached to the camera is 7.2 mm x 0.72 = 5.2 mm.

There exists different methods for attaching a converter to a compact camera. The most common method is to use an adapter tube with female threads. The tube is attached to the camera body and has room inside it for the compact camera's non-detachable lens to focus and zoom in and out. The converter is attached to the outer end of the adapter tube with male threads of the same diameter as the adapter.

Finding a Wide Angle Converter and Adapter Tubes

I wanted a wide angle converter that could be used both on my Canon Powershot G5 and Olympus Camedia 2020Z.

There is a lot of really bad conversion lenses on the market. If you want to see what type of product to avoid, please see the blog. This review, however, is about products that I find useful.

All the leading camera manufacturers make quality wide angle converters for their non-DSLR cameras. They are good, but they're also expensive. For the Canon Powershot G3/G5, there is the Canon WC-DC58N (0.7X) converter with 58 mm thread ($150), and for the Olympus C-2020Z, there is Olympus WCON-07 (0.7X) ($130) and WCON-08 (0.8X) ($140), both with 55 mm thread.

In addition to the converters from the major camera manufacturers, the following manufacturers have a reputation for making useful converters that can be attached to most digital compacts with a suitable adapter: Kenko, Raynox and Tiffen.

After considering what was available I ended up buying a Raynox DCR-720 (0.72x) wide angle converter for $55 off eBay.

What attracted me was the modest price, and also that it had a 52 mm thread. Since I both own a Canon G5, and an Olympus C-2020Z (I still use it for infrared work) I noticed that I could get third party adapter tubes with 52 mm threads for both. For the G5, I use the G3/G5 Lensmate 52 mm adapter tube ($25), and for the Olympus C-2020Z, I use the Kenko 41 mm-52 mm adapter tube ($16).

Using 52 mm adapter tubes also let me use the 52 mm filter collection I built up for my Nikon SLR film body and my Kodak DCS-460 on these two compacts.

Findings

Putting the Raynox DCR-720 in front of the Canon Powershot G5 fixed lens gives a considerable wider field of view. At the wide end, the G5 has a focal length of 7.2 mm. The Raynox DCR-720 multiplies this focal length with 0.72, so the combined focal length at the wide end becomes 5.2 mm. The so-called “crop-factor” of the Canon Powershot G5 is 4.8x, so if we express field of view in 135-format equivalents, the converter extends the wide end of the Canon Powershot G5 from 35 mm to 25 mm.

The image below shows a photo taken with my Canon Powershot G5 with the zoom at its widest setting. Move the mouse over image (requires Javascript), or click here, to see the effect of fitting the Raynox DCR-720 converter to the camera and re-shooting from the same position.

Move mouse over image to see the effect of fitting the converter to Canon G5 (requires Javascript).

Sharpness of the combination is good, with just a little softness at the edges, even at wide apertures. Colour rendering is neutral. Barrel distortion, however, is pretty bad, but can be corrected with Panorama Tools.

A peculiar quirk is that when you stick an adapter and an wide angle attachement on a Powershot G5, they block the G5's focus assist beam. This means that you lose the autofocus if the ambient light is so low that the focus assist beam is needed.

Conclusion

Nothing beats a DSLR for flexibility, but sometimes you want to travel light while still wanting to have access to a wider field of view than the zoom on your compact gives you.

On those occations, a wide angle converter of reasonable quality, such as the Raynox DCR-720, may save the day.

Links

I've registered a couple of webpages that publishes reviews of various converters:

• http://kazutoku.maxs.jp/converter/index.htm
• http://webpages.charter.net/bbiggers/DCExperiments/html/d7_add_on_lenses.html
• http://forums.dpreview.com/forums/read.asp?forum=1033&message=16321763
• http://www.cs.mtu.edu/~shene/DigiCam/User-Guide/FZ-30/Converters/Lenses/WideAngle.html

These sites has full size sample shots of some of the converters:

• Lensmate: G7/G9 Wide Conversion Lens Samples
• Raynox: Olympus SP-500UZ Examples