Thanks to Luminaire for the lamps I tried them out in my 1950 preheat "shoplight" and they lit right away. I first tried with one IF and one CWX. I got them recently at a local hardware and they say Buyers Choice on them, and they were made by Sylvania and were selling for $1.89 each, so I got 2. The F40T12IF seemed no dimmer than the CWX lamps. Sylvania could bring them back if they could get the CRI to 90. Isn't CRI on those at 89%.  I need to test them with a WWX to see what that looks like!


Powell

IFs would technically be exempt, the minimim CRI is 87. I saw one source say the IF has a CRI of 92, another said 89
 Confusing!

I expecting that the Sylvania IF would have a Ra8 of over 90, because as its name suggest (Incandescent Fluorescent), its light is indistinguishable from an incandescent lamp. Even 827 and 927 triphosphors fluorescent lamps have a light which is far from incandescents (Similar to that of a typical white HPS lamp [Philips SDW]).

Similarly, the Iwasaki SDX white HPS lamp, should have at least 2800K and over 90 Ra8, because its light is indistinguishable from a halogen lamp (The reason why it has been described the highest quality sodium based light source regardless of is it a white HPS, a regular HPS or a LPS lamp: No other brand of white HPS lamp have an incandescent/halogen color, and they tends to be in the pink/golden side of the white, rather than the yellowish white of incandescents and halogens).

The F40T12N  ( Natural) 3700K that's sorta pinkish has a 90%CRI and is still listed ( or recently was) by GE ! 


Powell

What about the Plant & Aquarium wide spectrum lamp? They have 89 CRI at a low colour temperature.