Question: If you pack more LEDs onto one bulb, is there a point when it can't be any brighter?

I just installed 18-LED 7440 reverse light bulbs. They look good; not too blue and pretty bright. I noticed on ebay that they have 68-LED 7440 bulbs. Will these be extraordinarily bright? Anyone have experience with them? It seems to me there may be a point at which the brightness will no longer increase based on the number of bulbs....like there may be no difference from 40 LEDs to 60 LEDs. Does anyone know this? I'd like to get the 68-LED bulbs but not if it's not going to be roughly 4 times brighter like one would think (18*3.7=68).

 

it might be brighter but not necessarily all in the right direction (?)

 

These are the 2 bulbs in question. 18 LED vs 68 LED

Wondering about this one (68 LEDs):

I have this one (18 LEDs):

If pics didn't work, I will fix them tonight.

(I'm not buying from the sites where pics are from...there were convenient from Google images.)

 

I'm no lighting expert, but the brightness does depend on the diodes. Certain LED diodes are better than others/operate at different wattages.

I want to take a guess that, while more LEDs can help with the brightness, it can also help produce the desired color so it's easily visibly from a distance.

KillerG is also right in regards to direction. Might not matter if there's a reflective housing (or at least not too much), but the direction the diodes points to does help with that factor.

To be honest, I wouldn't trust eBay for assembled LEDs (in this case, bulbs). Would go for a reputable site or at least one with a decent track record. Got some pretty cheap bulbs from a local vendor, meh. Got some from V-Leds for a tad bit more. 10x brighter than my old, single diodes. For example, my license plate bulbs burnt out and stuff a lot. Single diodes. Loose fit. Replaced with a high-powered bulb with 4 diodes that ran at a higher wattage, had a built-in heat sink...Thing was heavier and a bit more bulkier than the cheap ones, but overpowered the old ones easily.

 

18 led bulb:

68 led bulb: