Does it really help to render in higher resolution and then resize?

plarff

algovincian said:

@algovincian So it's down to the filtering radius/ratio, a double size render is effectivly using half the filtering radius, plus a little bit more with the resize interpolation. What filtering are you using? Mitchel at 1.0?

Don't know what filtering the denoising uses but could you redo the 1st one with lower filtering radius, guestimate what the 3rd one effectively is, I think triangle is bicubic if I remember correctly..

All 3 renders in my examples used the default Pixel Filter in DS (Gaussian with a radius of 1.5). I didn't save the scene and don't feel like running them all again, but if you run the tests yourself, I believe you'll see that using Mitchell with a radius of 1.0 will indeed yield a sharper image (sharper than the 3X render resampled in my example, too). However, this comes at a cost - the image will be substantially more noisy (grainy).

IMHO, I don't believe it all comes down to filtering. Like I said in my original post, running the de-noiser on a higher resolution image helps the de-noiser to perform better.

- Greg

This is an old post, so i hope "Greg" answers. For instance doing a 5000 iteration render what would you make DAZ Denoizer at to get best out of it?

for instance id set it to 4990. I find the last 10% is enough to smooth out and sharpen the image more but i may be wrong.