The figures from the product announcement reveal an important difference: Iris Gold lets more light through than Plum when set to its lightest setting. However, the photochromic lens does not become completely clear.
The figures from the product announcement reveal an important difference: Iris Gold lets more light through than Plum when set to its lightest setting. However, the photochromic lens does not become completely clear.
A comparison of Plum and Iris Gold
SunGod quotes the following figures in this product announcement. These are not TOUR measurements.
| Characteristic | 8KO Plum | 8KO Iris Gold |
| Tinting | Festival | Photochromic, self-tinting |
| Filter category | 2 | 1 to 3 |
| Light transmission | 31 per cent | 47 to 11 per cent |
| Adapting to changing light conditions | No | Automatically within the specified range |
8KO Plum: a solid shade for even conditions
According to the product description, the 8KO Plum transmits 31 per cent of visible light and falls into filter category 2. SunGod describes it as a high-contrast option for overcast conditions. Whether it actually makes it easier to spot road damage, leaves or uneven surfaces is not substantiated by the information provided.
The practical difference compared to a photochromic lens is that Plum does not change its tint. There is therefore no waiting time when the lens lightens or darkens. However, the light transmission remains at 31 per cent even when the route takes you through a dark section of woodland.
The selection is therefore based on the darkest section of the route that is regularly travelled, not just the light conditions at the start. The fact that the route is suited to overcast skies does not mean it is suitable for twilight rides.
8KO Iris Gold: self-tinting, but not clear
According to the information in the specification, the photochromic 8KO Iris Gold covers filter categories 1 to 3. Light transmission ranges from 47 per cent when lightest to 11 per cent when darkest.
Iris Gold therefore offers a wider range of adjustment than Plum: it can become both lighter and darker. However, even at its lightest, the lens allows less than half of the visible light to pass through. Anyone looking for a largely clear base tint should therefore not rely solely on the term ‘photochromic’.
The speed at which the lens lightens is also important when moving from a sunny road to a shaded alleyway. This product announcement does not specify a particular reaction time for Iris Gold. It therefore remains unclear how quickly the lens reacts to the typical changes in light encountered on an autumn ride.
TOUR explores just how different photochromic models can be in the Practical and laboratory testing of 41 Eyewear’s sports glasses. However, results from other glasses cannot be applied to Iris Gold.
Models, materials and price
According to this announcement, Plum and Iris Gold are intended for the SunGod models Ultras Air, FORTY2s, Velans 2 and Vulcans Vent. Both versions utilise the nylon technology known as 8KO.
SunGod cites complete UV protection and a lifetime manufacturer’s warranty. The advantages in terms of weight, optical quality and impact resistance compared with polycarbonate are based on the manufacturer’s claims; they are not the results of a comparative test of the new lenses.
The starting price quoted in the announcement is 170 euros. The document does not provide a complete price list for the individual combinations of frames and lenses. Further information on one of the planned models is available at the Introducing the SunGod Velans 2.
Context: The lightest shade is the deciding factor
Plum and Iris Gold are based on different concepts. Plum offers a constant tint with 31 per cent light transmission. Iris Gold extends this range to between 47 and 11 per cent, enabling it to adapt to different lighting conditions.
For road bike and gravel rides involving frequent changes between open and shaded sections, this wider range generally offers greater flexibility. However, without details of the response time and without a practical test, it is not possible to assess conclusively how well the adjustment works whilst riding.
Anyone who often sets off late or drives long stretches through woodland should, above all, compare the maximum light transmission. ‘Self-tinting’ does not automatically mean that a windscreen is suitable for low-light conditions.
Which feature is more important to you on autumn trips: a consistent tint or automatic adjustment to changing light conditions? Let us know in the comments!
Marc Strucken
Editor