Denoise adds considerable time?

[hismaimai2000]

Rendering an animation, 8% Noise level limit: Denoise off, 5:45/frame. Denoise on, 13:30/frame. That's a big disparity.

[romullus]

Well, let's look at it this way - if you'd render without denoiser for 13:30, does the image reach acceptable quality? If answer is yes, then forget denoiser and render without it, otherwise denoiser does save your time. Having said that, it still sounds strange that denoising takes more time than the actual rendering. What resolution you're rendering to?

[maru]

Is that reported time the overall time from start to finish, including denoising, or is it the time from start to when Corona stops rendering and starts denoising?
Generally the denoising on/off should not affect rendering time.
If your image is in large resolution and there are many render elements (e.g. LightMix), then denoising can take a long time.