Where did you come up with this?
> "new led technology the variance of the wavelengths on the light spectrum is much lower, probably -5 to 5 nm."
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> "Scientifically, this would mean that if a gel is made to cure at 400nm then any uv led lamp would cure it unless there is an issue with the lamp or process itself - hand too far away, dirty lamp, etc."
Wavelength is not affected by hand too far away, dirty lamp.
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> "if the industry says you need the lamp that matches the brand then they will expect you to have it. However, I’m just not sure that this is scientifically right. Lamps are expensive and I really think that lots of people are being taken for a ride by companies who have released new gel lamps but said you still need a specific one for their brand."
Where are your qualifications or scientific evidence to dispute this?
Perhaps you also dispute this statement by the British Association of Dermatologists:
"make sure that you use the recommended UV lamp for curing, and read the instructions carefully. Using the wrong lamp may mean that the gel polish does not cure properly, and this means an increased chance of allergy. Avoid any direct skin contact with the (meth)acrylate nail product.”
I've written a very complete article which is the top post on this forum. This is based on my experience developing UV gels during the past nine years within our company, employing two chemists and having done significant additional allergy related research myself. If you have any facts that dispute anything that I have written, I would be happy to discuss this.