If you are going to compare LEDs from different suppliers, this information may be useful:
Probably far more than you want to know about light, but when choosing LED replacement lamps there are lots of variables. Most modern LED lamps are made of collections of SMDs attached to different lamp bases.
One of the difficulties is there are many different SMDs. SMD stands for Surface Mounted Device. There are many different electronic components that are SMDs, one type is a LED. They are usually identified by a number, and different SMDs produce different amounts of light, different color temperatures, etc. The only way you can compare how much light a lamp will produce by the number of SMDs is if they are the same model. Otherwise, a 9 SMD lamp may produce more light than a 24 or 36. Since many suppliers do not include the model # of the SMD they use, it's tough to compare.
The best method of comparing light output is by looking for the Lumen specification. That is the total light produced by the lamp. If you want the same amount of light produced by your current incandescent lamp, you need to go to a site that lists the different types & their lumen output, for example, Service Lighting
. In most cases, LEDs produce less light than incandescent lamps, but they are getting better.
If you are purchasing a fixture that includes the lamp you may find the specification of light output is Lux. Lux describes the amount of light on a surface at a specific distance. The important point when comparing fixtures by Lux is distance & coverage area. Two fixtures with the same Lumen lamp may produce very different Lux because one spreads the light over a wider area. This is why a reading light (with a narrow beam) seems much brighter than a general area fixture with the same Lumen lamp.
If you are concerned about color, Warm White is the description most often used to compare to an incandescent lamp while cool white, white, or pure white compare to fluorescents. The technical description for the color attributes of a lamp are complex, but an incandescent lamp produces a color temperature of somewhere between 2800°K and 3200°K and a CRI of 100.
Color Temperature is given in degrees Kelvin (a scale that starts at absolute zero as 0°K and shifts from infrared to red through the visible spectrum to violet and beyond (a clear blue sky without the sun is around 20,000°K). A cool white fluorescent lamp produces light with a color temperature around 6000°K.
Basically, Color Temperature is a method of describing the color an object will radiate if it is heated until it glows. It is more technical than that, but a tungsten filament will actually be at the same physical temperature as the color temperature it produces, while other types of light sources "manufacture" the color without actually being at that temperature.
CRI (Color Rendering Index) is a number between 1 & 100 with 100 being the equivalent of an incandescent lamp. As the number drops, the source produces light that does not render colored objects correctly. For example a Sodium Vapor street lamp has a CRI of around 24. That is why your red vehicle and lips look black in the parking lot.
CRI specifications are rarely given for LED lamps, but most of them are pretty good. CFLs sometimes have very poor CRIs which is why there are complaints about "green" colors.
One last consideration - many LED replacement lamps have voltage regulators built into the electronics. The good - they produce the same amount of light over a wide range of voltages & are less likely to be damaged by high voltage such as when your converter goes into the equalization stage. The bad - many voltage regulators create RFI (Radio Frequency Interference). They may cause lines in your TV picture or even block weak signals, and produce buzzing noise particularly on AM radio.
One solution is to purchase inexpensive non regulated LEDs & toss them if the burn out. I've used replacements panels such as these
from Hong Kong - they are cheap,warm white, and I haven't lost one yet, however be sure they offer the base you need. The suppliers constantly change so you may need to do an ebay search to find a current supplier, and be willing to wait for the shipping time from Hong Kong, but you can't beat the price!
I'll stop rambling now - I'm a retired teacher & once I get started it is difficult to stop!