For photorealism then u have to use caustics/mentalray
No that's not true, that's a misconception that turning on raytracing will make things look better it doesnt always! You can get photoreal results with maya software render. To get a good looking metal material it's all about the spec component and the reflections /refractions etc. If you are not raytracing you will need environment maps to achieve the look you want.
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