Comfy UI K sampler Explained | How AI Image generation works | Simple explanation

This is my attempt to try and explain how Ksamplers in comfy UI work, while also explaining a VERY simplified explanation of how Stable diffusion and Image generation works.

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[Foolsjoker]

One of the few channels actually breaking down the nodes. I hope you make more of these.

[alexfreeman]

That is most well explaining video about the KSampler node I have ever seen! Thank you for giving an understanding of the nodes!

[ScraggyDogg]

Thanks, I've strung samplers for upscaling, but is there any benefit in a basic workflow of using 2 samplers at 15 steps & next on 5 versus one sampler on 20 steps ?
Just wondered

[Historias]

I have a LEGION 5 laptop, Ryzen AMD, NVIDIA GEFORCE GTX 1660 6gb graphics card, do you think it can work? I ask because I have tried several tutorials and they all give an error in KSAMPLER or UNSAMPLER. Do you have any help for my case?
I have tried to change video styles and it gives an error in KSAMPLER ADVANCE

[johnriperti]

Thanks for the details, please make more videos like this. I really helps to understand the concepts.

[Antilopax]

Does this mean you can use KSampler to actually denoise a noisy photo? Like: Input a noisy image (non ai-generated) and tell it to finish the last 4 steps out of 20?

[stefanvozd]

Thanks to great vid! Subscribed to Patreon!

[Shirakawa]

Very good explanation, it helped me a lot!

[studiokaralis]

Thanks for the explanation!
By the way - EULER is not pronounced "juler" but rather "OILER".

[HTRO-EG]

you are amazing
but :
You are presenting a podcast on a video that contains an image that does not move

[schoen_ing]

Brilliant explanation!
Please more!
Could you talk about CFG next?

[uncertainultradian]

About the quiet volume: sorry if you already know all this, I hope it doesn't sound patronising, but I thought I might try to help. I looked at the audio file from the video and it kind of looked like it just hadn't been normalised, but I don't know if it's different before and after YouTube processes it. [More below]

If that's not the problem, I noticed at 0:32 there's a click sound, and noises like those tend to be picked up very strongly by microphones as the loudest thing they hear; so it may be that the voice audio is being picked up as a relatively much quieter sound than any incidental clicks etc. If that might be the issue, I usually manually lower any volume spikes while editing so that the voice becomes the loudest thing in the audio file, but applying powerful audio compression to the file might be another option.

In the past I've tried to upload stuff normalised to supposedly ideal LUFS (about -14) for YouTube, but I found that it made no apparent difference, so I went back to normalising to -0.2 dB for simplicity. I don't really understand LUFS though, so maybe I'm missing the point there.

The video's very insightful, thankyou. 😊

[Pauluz_The_Web_Gnome]

Hi nice video, but your voice is a little soft...

[ankethajare]

does keeping my steps upto 200 steps make sense?

[screwyougoogleplusnoreally]

I've been using a1111 and invokeai for several weeks, watching videos and reading blogs.You've taught me more about how sd works in your first three videos than any other sources. You are hitting the right balance of "Do this to make that" and how sd works to turn an idea into an image.

I'm done with sd and invokeai. There are simply too many balls in the air. The generation process is far from intuitive and it's too complex to represent in a traditonal, browser-based UI using menus, tabs, and panels.

Serious process management in industry and finance use workflows for good reasons.

[jalpranjal]

that was very informative ! thanks. Can you do video explaing the latent image and what role does it play in image generation? Thanks

[Miner]

I have a question that I can't seem to find the answer to online so maybe you'd know. I'm testing out using ksamplers at different intervals. When I use a setup with 3 ksamplers (refiner for 2 steps, then main, then refiner again at the end) it seems to produce decent results. But when I split the main ksampler into 2 ksamplers (both with approprate start and end steps, no noise added, noise carried over, etc) it produces a different result than the 3 ksampler setup. Shouldn't the results be consistent no matter how many ksamplers there are, given that all of the external parameters are the same?

[schoen_ing]

Brilliant explanation!
Please more!
Could you talk about CFG next?

[RamirosLab]

Hey! ... great explanation. Thank you for taking the time R&Ding this! Finally I understand the Latent part of this node!... Thanks!

[spoonito]

thanks for explaining this so clearly!