Thank you very much for your FFL519a 3750K test report. Im particularly fond of Rosy emitters and recently bought some FFL519a 3750K, ordered April 13, 2024.
Contrary to posts by several other people, promising Pink Tint, the LEDs I received were not pink at all. I then wrote to Fireflies to ask if they could provide some of the Pink ones. They told me they no longer have Pink FFL351a 3750K
So, people who got them earlier, were lucky. The presently shipping FFL351a are no longer Pink. At least not the two I tested:
There has been a similar shift in the 519a 4500K LEDs that I have bought in the last few months. They have become greener, and even after DeDoming, they barely go below the BBL.
Here is a recent example of a DD 4500K 519a that I put in a Sofirn SC21 Pro:l
I prefer Tint DUV to be lower, and that is why I bought the FFL351a 3750K. Unfortunately, they did not live up to my expectations for negative DUV.
This sort of thing happens a lot. For example, when the sw45k first came out, it Was Very Pink. Each later batch was less Pink.
This also happened with the stock LEDs in the TS10. At first they were very close, to slightly below the BBL. Later batches have become increasingly Greener.
All that to say, i think the Pink Tinted FFL351a 3750k sounded like a great alternative to DD 4500K 519a. However, I was unable to buy any of the Pink tinted FFL351a 3750K. It seems the Pink ones were an earlier production run than those being sold now. Also true about recent 4500K 519a, they have become less Pink.
Fwiw, i tested the FFL351a 3750K in a Sofirn SC21 Pro with a Pebbled Tir. I compared it to an other Sofirn SC21 Pro, also with a Pebbled Tir, using a DeDomed 4500K 519a. fwiw, the FFL351a produced 7% higher output, using the same battery, and same ceiling setting of 120/150.
So, though the FFL351a 3750K had a slight output advantage over DD 4500K 519a, the FFL tint was greener, which for me is not a benefit.