There are a zillion posts on other forums (example below) that talk about the color shift of AB vs power setting, invariably purporting brands like Elinchrom and Profoto have less or no color shift VS power. Yet nobody (except me) ever actual tests the color shift of other brands.
http://www.fredmiranda.com/forum/topic/1063836This is totally false and I suppose the reason they don't test other brands or compare them is that either they don't own the other brands, or they prefer gossip to fact.
I have done many many hours of comparison testing over many years and the clear facts are that Elinchrom RX600, Profoto D1 and virtually all monolights exhibit almost exactly the same color shift vs power setting as AB or WL. This shift is 75° to 85° per f stop of color temperature per f stop of power reduction. In fact from Full power to -5f, AB actual has 25° less shift (-375°K) than RX600 (400°K) and 75° less shift over the same range as Profoto D1.
By contrast, Einstein maintains within +/- 50° color shift at any power setting from Full to -8f stops. The only other lights on the market, to my knowledge that accomplish this are the $10,000+ Broncolor IGBT controlled pack and head systems.
There are a couple of Chinese flashes now on the market under various brand names that use IGBTs, but have no constant color circuitry. I have bought and measured these and found the color shift upward (bluer) as the power is adjusted from Full down to -5f stops.
Rob Galbraith is currently comparing the "mystery meat" brands to Einstein and is well aware of the totally false claims and specs associated with them.
Here is a seven year old independent comparison between Profoto, Elinchrom and White Lightning (which has the same color shift as AB)
http://www.prophotohome.com/forum/light ... sults.htmlFinally, the results of my very scientific, unbiased testing can be seen in graphic form at
http://www.paulcbuff.com/e640.php (Click "Comparison Data)Since I am banned from posting on Fred Miranda Studio Lighting Forum, it would be nice if some reader here would correct the record with a post to the FM Thread above if you have access to post there.