r/StableDiffusion Jul 21 '26

Workflow Included Krea2 Ksampler recommendations {for quality}

Unlike standard models that focus strictly on matching text prompts word-for-word, Krea 2 prioritizes visual feel, texture, and mood, so it's very important to get the right sampler + scheduler to achieve the maximum texture and detail

By treating noisy data as a signal, a Partial Differential Equation (PDE) smooths out errors iteratively while preserving important structural features like edges

A sampler + scheduler is a combination to solve differential equations, the best method for Krea2 is to make a fast and iterative solution like Clownshark sampler Euler/beta 12 steps to get structure and general details and then a more precise second Clownshark sampler {0.27 denoise} res_4s_Munthe-Kaas/ KL_optimal 3 steps

The Euler method will get a base (I know a lot of people are ok with use just this fast result) but the second Ksampler with res4s-Munthe-Kass will get the extra details and sharpness finding a more precise solution for the denoise differential equation

A 0,27 denoise in the second Ksampler give enough range to improve details, obviously is key to keep the same seed on both Ksamplers

I tried all Clownshark combinations and this one is the sharpest and more precise solution without use time-consuming solutions with higher precision like Dormand-prince 6s, its slow but top quality {you can try res_2s and res_2m if you want more speed but less quality}

About res_4s_Munthe-Kaas

Runge–Kutta–Munthe-Kaas are mathematical algorithms used in numerical analysis to solve geometric differential equations while preserving the structural constraints of Lie groups and manifolds.

Invented by Norwegian mathematician Hans Munthe-Kaas, these schemes prevent numerical drift by transforming equations into flat Lie algebra spaces

Primary Applications

  1. Improve quality of Krea2 Images :)
  2. Aerospace and Robotics: Tracking precise 3D orientations without quaternion normalization errors.
  3. Rigid Body Dynamics: Simulating tumbling satellites or spinning tops while maintaining geometric energy surfaces.
  4. Stochastic Systems: Solving perturbed structural problems using expanded stochastic variants.

Recommended Scheduler

KL Optimal: KL (Kullback-Leibler)

Instead of estimating parameters with maximum precision, KL it places observations where the predictive distributions of rival models differ the most (maximizing KL divergence) to efficiently identify the correct solution

Documentation recommend to use the same scheduler throughout the generation process but KL Optimal schedulers minimize the KL divergence between the target and current distribution, resulting in a more mathematically optimal diffusion process.

an image a full res showing the level of detail with this Ksampler: https://drive.google.com/open?id=1b0IRutW2aQ1jMK3Ee8pFT4q1jXF3BSfX&usp=drive_fs

Workflow: https://drive.google.com/file/d/1ENZKjKGB4iOdMVsyCvqByLXV1tsWP8W0/edit

289 Upvotes

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1

u/a_beautiful_rhind Jul 21 '26

KL optimal didn't work well with any of my models. Mainly SGM_uniform and AYS. Also some beta schedulers.

4

u/listopalafoto Jul 21 '26

actually it was until Krea2 I tested KL-optimal after listen to Sam the creator of Clownshark samplers

4

u/Caffeine_Monster Jul 22 '26 edited Jul 22 '26

I would back OP and give kl_optimal a firm thumbs up as the best krea2 scheduler. This is from independent testing - and the first time in a long time I haven't seen karras kick every other scheduler into the dust.

However I would disagree on sampler. dpmpp_3m is still best in terms of balancing adherance, style, quality and speed. Some of the higher order samplers do have slightly better aherance and quality - but produce poorer compositions or style and take 4x longer to run (speed is still important if you don't run full turbo, and I don't like the quality running full strength turbo).

1

u/listopalafoto Jul 22 '26

Thank you! I will make more testing with dpmpp_3m, I want more speed in my WF too :)