The reference sampling implementation auto adjusts the shift value based on the resolution, if you don't want this you can just bypass (CTRL-B) this ModelSamplingFlux node.
If you get an error in any of the nodes above make sure the files are in the correct directories.
See the top of the examples page for the links : https://comfyanonymous.github.io/ComfyUI_examples/flux/
flux1-dev.safetensors goes in: ComfyUI/models/unet/
t5xxl_fp16.safetensors and clip_l.safetensors go in: ComfyUI/models/clip/
ae.safetensors goes in: ComfyUI/models/vae/
Tip: You can set the weight_dtype above to one of the fp8 types if you have memory issues.
detailed cinematic dof render of an old dusty detailed CRT monitor on a wooden desk in a dim room with items around, messy dirty room. On the screen are the letters “FLUX Dev” glowing softly. High detail hard surface render