Hikvision 2042 IR 4mm vs 2032F IR 12mm

I didn't want to wait for a 12mm 2042 to arrive from China so I swapped the lens from a 2032F 12mm to a 2042 4mm. Stupid I know but everything looks excellent with the exception of the converted 2032F with the 4mm lens - at night the IR is very centered, concentrated and appears to be like a spot light vs. evenly dispersed. Question: would the 12mm IR board be different IR bulbs to have a more spot light focus (which makes sense since the 12mm would likely require spot like illumination since the FOV is much more narrow) or would the difference be driven by software (although this is unlikely since firmware is not specific to lens & model)?
Thanks

I believe I answered my own question looking at replacement IR boards on Ebay - thanks!

FWIW, I'm pretty sure the 12mm version has IR leds that are more tuned/focused for the smaller field of view (viewing angle), which explains what you noticed.

I'm wondering if the IR board from the newer 2042 models can work in the 2032 body? Anybody done that? thanx.

If memory serves, the 2042 and 2032 (not the 2032f) share the same body - and I believe it uses the same old 4 wire configuration, whether or not the IR board exactly fits I don't know/recall.