I agree. I run a 50/50 mix over my own rig and found it really yellow unless I lower the intensity of the CW LED's. I ended up supplementing with T5's to fill in some of the higher Kelvin Blue and it made a huge difference.

what kind of LEDs are you using and what batch number did you get for your cool whites? the good ones are 6500 to 8000K which has no yellow at all. at worst they are 6500K, which still shouldn't have any yellow. any bin number for "cool white" should give you a white with a slight tinge of blue.. kinda like a ice white for the lower batches and a real light blue for the good batch numbers.. now this is for the older ones and I notice that some of the newer ones are down to 5000K for the bottom end of the range but this should still not show any yellow. nutral white might have a tinge of yellow, but the warm white is where you should get your yellow.

ya that is an issue with using the royal blue.. to me also they look like there missing that bottom end purple that makes the tank look like it has the old URI super actinic VHO's like i used to use. with the avilability of the true violet becomming better this should be a thing of the past.

I am waiting for the LEDs I ordered and I am going to do some color comparasons with different combos to see what I like. I have a couple of each comming nutral white cool white RB and TV. right now the new trens seams to be 1NW to 2TV, the old starting point was 1CW to 1RB, so once I figure out how to get an accurate perception of the colors I will post something. but it won't be anytime soon. my newish job kinda kick the heck out of my time.

Steve

What is TV ? True Violet?

Is that Radium on an electronic ballast? On a M80 I find it to be blue certainly but much closer to white/blue than other 20k bulbs I have seen...

yup

Steve

I got my Cree XP-G Cool Whites from rapidled. I ordered two different times and both look about the same in colouration. Sorry I don't know the BIN numbers on them. To me they should be called warm white.

If you go back and look at the old 6500 MH people used...they are not pure white either, they definately had yellow. A pure white is more like 10k....and think of an XM 10k bulb, that IS white.

Anyway they list these LEDs at 5000-8300k. To me this range is not pure white and either are the LEDs.

My radium is not on an electronic. Its on a magnetic ballast but not the M80 because it's 400w. With just the MH running...I don't find it all that blue.

thats weird, the 6500K LEDs I played for when I was lighting my matis tank were white. I switched to a 10000K LED and it was a light blue. almost makes me wonder if some of these companies are buying seconds to keep the cost down while making a profit.

now my playing has been with the XR-E's so maybe the newer ones put out more yellow in comparason as they have a higher output. this would require more blue to offset the white element so that could be it also.

Steve

More progress being made.... This is a hefty build.. Here are all three pendants in various stages of completion.

http://i229.photobucket.com/albums/e...reestages2.jpg

http://i229.photobucket.com/albums/e...hreestages.jpg

Now that the metal work is done for the pendants I can focus on the tedious aspect of positioning the LED's, epoxy-ing the last set in place, and soldering. I've set up a nice work station right in front of my TV for this part...

I just read today a post were someone stated that the XP-G's are more yellow than the XR-E.....so maybe that is what we are experiencing. Also BIN # does change things as well.....the cool whites have a large range of spectrum really.