They test to see if he is in fact affected by the strength of the sunlight – while he was outside at dawn, it did in fact feel less strong, but he was partially buried in sand and the pain ramped up over the time he was out, so it wasn't a particularly good indicator. It turns out he is in fact affected differently by different strengths of sunlight; weaker sunlight is confirmed to feel less painful and he loses his senses less quickly this time than when he went outside earlier.

After a short while, they go back inside and he cools off – it's not yet sunset, it's just slightly dimmer, so the sun still has quite strong effects on him. They have food, or rather Matt and Sadde do, though Theo cooks it because he hasn't lost that ability despite becoming a vampire, and it gradually gets towards sunset.