Credit must be given to Panasonic for their creativity and originality in selecting focal ranges for their L-mount zoom lenses, particularly the S 18-40mm F4.5-6.3, and the S 20-60mm F3.5-5.6. No other manufacturer has ever produced lenses with these unique 18-40mm or 20-60mm ranges before.
Another point worth highlighting is how compact the new 18-40mm lens is! Before making the size comparison below, I hadn't realized it would be significantly smaller than the S 20-60mm, but it clearly is. Just take a look at the size difference between the two:
Panasonic S 18-40mm vs 20-60mm Size Comparison
I'm not denying that the 20-60mm offers a more versatile range for many, thanks to its 60mm maximum focal length, which also contributes to its larger size. In addition, it has a faster aperture range (f3.5-5.6 vs f4.5-6.3). However, if you're looking for the most compact option, the S 18-40mm is undoubtedly the winner. Below is how they look on the Lumix S9:
S 18-40mm and S 20-60mm when paired with the Lumix S9
I really like the new S 18-40mm F4.5-6.3 and believe it fills an important gap not just for Panasonic, but for the entire L-mount ecosystem. I do wish it extended to 50mm, but I can still live with its current range.
Panasonic S 20-60mm F3.5-5.6 vs Panasonic 18-40mm F4.5-6.3 Specs and Feature Comparison
Here is a brief specs comparison of the two lenses for further analysis:
