Some LED have "holes" in their spectrums. This makes post CC actually impossible. Adding gels? Not sure. I have an LED that requires a magenta. To get some physics at this get an eye spotter spectrogram site. This will show up the "spikes" or holes. I was given the opportunity to view my light that way and it made me rock back on my heels.
+1 Grazie. It's a bit more than degrees Kelvin or white balance.
Those reference markers only hold up with analog lighting: LED spectrum can be swiss cheese by comparison.
Some LED lighting is more sensor-friendly, but you're going to pay $$, and full spectrum they are not..
LED fixtures are highly variable (in spectrum) and some are useless as video light sources (for the reasons stated above). In general you get the quality you pay for, but even that isn't any guarantee of a usable spectrum.
Here's a layman's article on color rendering in consumer LED lamps:
Without knowing what the OP is using for an LED source, you can't really make a guess about what the problem is. Yes, it's good to know that many non-tungsten/non-daylight sources have holes in their spectra that make them just unusable. Sodium vapor lamps are a great example where some colors can't be seen by the naked eye.
What the OP says is that his lights look a little blue. Usually this is countered with a little CTO gel, often just an eighth CTO will do it.
Tungsten sources usually vary between warm (orange) and cool (blue). This is fairly natural looking and is easily tolerated if it's a little off. All other sources vary in warm/cool and ALSO in Magenta/Green. Magenta/Green looks unnatural and you usually want to correct it. Correction is hard if you don't either have a good color meter OR a properly calibrated field monitor. Both are rare for hobbyists.
For fine tweaks I usually keep an eighth CTO (Orange), an eighth CTB (Blue), an eighth MinusGreen (Magenta), and an eighth PlusGreen (Green) in my kit. I also keep the other heavier grades of color correction gel but the eighths are as fine as you can usually go.
I generally buy Lee because they look best to my eye, but whether you buy Lee, Rosco, Gam, or other, you should stick to one manufacturer. Their products don't look alike even when you'd think they should.
Bast@rd Amber is a theatrical color and not really what you want for color correction. Keep the theatrical gels separated from your color correction gels if you want to save time.
White balancing your camera is something you ought to do as a matter of course, but you should do it based on one good light source. Like the sun if there's sunlight in the shot, or like your key light. Since LED color will vary from fixture to fixture, you need to set your balance to just one and then correct the others.
You want the WB source to be whichever fixture is lighting an object of known color. We know what color people are (within reason) so a key light is a good candidate.
Last tip. Four sheets of eighth blue does not equal a Full Blue CTB (Lee 201?). Every sheet has a little bit of off-ness to it and when you stack eight sheets you multiply that off cast eight times. It's much better to use the right gel than to stack halves and quarters. Also, watch your gels to make sure they aren't getting damaged by heat. It's much less of a problem these days but you should keep an eye on it anyway. Colors change as gels cook.
Sometimes the theatrical colors are what's available if you have college or community theater in your area, so if B@stard Amber looks okay, use what works. My perspective is from working in crews. It's better to have the expected gel rather than making sure everyone knows to use a certain theatrical color. Standardization helps people hit the set running, especially when crew composition changes frequently.
Here's some gel marking trivia for those who don't know. It's useful to mark gels with a sharpie to show what it is, especially if it only has a number. For theatricals I write out the name but for color correction I use a common shorthand. Mark it with a zero or circle and draw lines though it like a pie or pizza. One line is a "Half", two is a "Quarter", four is an "Eighth". Very quick to write, very quick to read, and you don't need to spell out the color since that's obvious. And only the color correction gets marked that way so you don't mix them up with theatrical colors.
This is the set electrician's way to do it. Camera folk, being more literate, still write it out long hand. Electricians sometimes miss it since they're looking for the shorthand.
I have a question for the group. This may sound silly but I know I'm not a pro cinematographer or anything more than a hack videographer so...
I know about white balance and post color correction etc. However, instead of using gels in all the lights (like in the OP's post) is there any particular reason that a CTO or any get for that matter could not be used at the camera lens. Yes I know of distortions and the like but have used it without too many issues and seen it used by others. Except for distortion (which could be minimal depending on the gel) is there any other reason it should not be done?
Apart from what you've noted about using actual gels made to use in front of lights, No.
There's a considerable range of colour filters made specifically to put in front of a camera's lens. They're not used much today because one can achieve the same in post. Filters made sense when shooting film prior to the digital age.