People apparently complained to Jack about the rosiness of the first batch of FFL351A 3700K and FFL505A. Jack listened, and made a neutral batch of those LEDs. Likewise, the FFL350RD were made about that time, so he made them neutral as well.
I am not sure if it was because JLHawaii requested them, but then came the rosy 4000k bin of FFL351A (which to my eyes was actually an improvement over the rosy 3700k). The FFL707A 4000k is supposed to be rosy like the FFL351A 4000k.
I am not sure why people like neutral tints around 4000k (which to me just seem banana yellow) so much they complained about the rosiness, but different strokes… I can tolerate a neutral 3000k and a neutral 5000k+, but the lands in between not so much. The rosiness was definitely a plus to me that makes 4000k pleasant.
I guess I will hoard my remaining supply of rosy FFL505As and try to use them sparingly. It would be nice to see a future rosy FFL505A in 4000k or similar, but who knows…
I can already tell from first quick look, they are slightly rosy. Really good as Allrounder, especially since they are not as rosy as the 3700 K FFL351A, at least from my perspective.
Im not sure which They you mean (were talking about at least 3 different LEDs in this thread). I look forward to your DUV results, from something other than Opple 4 (which can be off by 0.0030 in some cases)
What makes them an improvement to you? I am extremely happy with the 3700 (first batch). Only issue I have is CCT shift - had to use a frosted optic for the D4K.
I’m much happier with neutral tints for night photography. If using multiple lights with different CCTs, but with significantly different tints, results in funky white balance.
The tint is a bit cooler, but just as rosy, in the 4000k variant. Unfortunately, it and all FF LEDs except the FF505A have that tint shift you note near the fringes. I think someone here mentioned how Cree solved this was dicing the phosphor, where you can see the phosphor on newer Cree LEDs no longer runs all the way to the edge, but on FF LEDs it does… But since the FF505A masks the phosphor to make the round light emitting surface, it does not have this tint shift effect at least.
