If the author would like, I self computed a j lens for the 27b version of the qwen model. I used it for my own exploration in this area, and can share it if you want.

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schmorptron 4 hours ago | parent [-]

I'm not the author, but I would like! Is it feasible to run on the same hardware as the 27b model itself?

	▲	lwarfield 4 hours ago \| parent \| next [-]
		The using a J lens is super cheap compared to inference. You basically add a single matrix multiply per layer. You probably wouldn't even notice the overhead in a good implementation. You should even be able to create a j lens from scratch, but it might take a while. I was able to do it in a few hours on an H100. Creating the J lens is basically the equivalent of calculating a few thousand training steps for a model (256,000 backprops in my case). I've got more details in a blog post: https://blog.lwarfield.dev/layer-scope/ I'm currently at work and can't those matrixes up until I get home. I'll update this comment with a link later.
	▲	jasonjmcghee 4 hours ago \| parent \| prev [-]
		Fwiw you can just Google this for a model and often someone has done it https://huggingface.co/eyes-ml/Qwen3.8-27B_jacobian-lens