50% - 55% (currently 51%) is the base humidity in my snake room (during the summer), but I also mist their tubs down once a day/every other day, too. So, that increases the humidity significantly for a few hours at a time. My tubs have really good airflow, so they only stay moist for a few hours at a time. So far, i've had nothing but full sheds and they're all eating and doing great. It gets really dry here during the winter months, though. Sometimes the humidity in my snake room will get as low as 16% during the winter. I am definitely getting a humidifier to run 24/7 in my snake room before this winter.
Just out of curiosity, I checked the current weather forecast for Bankok, Thailand and Kuala Lumpur, Malaysia. There is rain in the forecast for both areas every day for the next 7 days. The humidity is currently 80% in Kuala Lumpur (temperature 81 degrees) and 90% in Bankok (temperature 80 degrees). So, I would say that this species is accustomed to much higher humidity in the wild. At least this time of year...