«Rain is only a problem if you don’t want to get wet.»
Old Samurai Saying in «Sin City: Sex and Violence»
After adding a holder for a water bottle to a Peak Design photo bag, I added an umbrella holder to the other side. This way both the water bottle and umbrella do not take up space inside, are readily available, and — in case of … wetness — the water stays outside the bag.
The umbrella holder has velcro on top, keeping the umbrella in place, and three metal ring openings at the bottom. In case I put it in wet or it rains in the holder, the water can escape.
Both holders are attached with belts (closed with velcro) and they can be removed — in a minute or so.
So yeah, overall, took perhaps five hours to sew both holders, but it did improve the bag.