TechClaude Opus 5.5 launches alongside GPT-6 Sol and Luna
Simon Willison reports that OpenAI's two models arrived about an hour after Anthropic's release. TestingCatalog cites a four-scene 3D comparison in which Opus produced more detailed renders at a higher total cost.
TLDR
Simon Willison reports that Anthropic released Claude Opus 5.5 on September 22, 2026, followed around an hour later by OpenAI's GPT-6 Sol and GPT-6 Luna.
TestingCatalog, citing results from the AI/ML API team, says Opus 5.5 produced more detailed renders across four scenes at a total cost of $4.37, versus $0.34 for GPT-6 Sol. The tests used one-shot 3D scene prompts, starting with an “animated fish school.”
In a separate creative demo, Higgsfield says it made a game-style pixel-art animation in After Effects using Opus 5.5 and Higgsfield, with jumps, changing expressions and a score counter.
Claude Opus 5.5 launches alongside GPT-6 Sol and Luna
Simon Willison reports that OpenAI's two models arrived about an hour after Anthropic's release. TestingCatalog cites a four-scene 3D comparison in which Opus produced more detailed renders at a higher total cost.