aDMC sample rate

[zeronove]

I'm just trying to look deeper in the image sampler (for nth time), which one works best, where and so on, you know; doing that, the show samples checkbox or the new sample rate render element are helping me a lot but I've some problems to compare adaptive subds with aDMC.
Using adaptive subds samples appear smaller and it's easier to fine tune their distribution over the geometry; using aDMC (that usally I prefer) often samples appear larger and more blurry that lead to a longer fine tune process.
For instance using adaptive subds the image shows clearly the underlaying geometry while in aDMC the image is almost full of one color (cyan or blue)

Not to say that the noise level of the final images has to be similar

Is it the expected behaviour? ...or have I missed some issue with aDMC?

[^Lele^]

For the aDMC the number of shades expressed by the sample rate image depends on the max sampling rate.
With 1-16 you get full 256 levels of brightness.
With 4, you only get 16 levels.
If it all come out blue, it likely means you're hitting max levels everywhere.
Raise the noise threshold and the number of max samples.
It'll have more steps to make to hit max, and it will be harder to make each step, so you should see more variation.
Unless, of course, you have a crazy complex scene that DOES hit max subdivs no matter what XD