This thread is "neutral ground" for busting the myths associated with your particular favorite kind of lighting. Use INC as shorthand for "incandescent". Subjective topics, such as use of color in GI, are out of bounds. We're only concerned here with the facts. Let's do this Snopes-style, with a "CLAIM"", followed by "TRUE", "FALSE", "UNPROVEN", "MOSTLY FALSE", etc. Here are mine:

CLAIM: LEDs don't have the same light spread (dispersion and distance) as INCs.
Verdict: FALSE. See pictures in post #69. Some LEDs are actually better at spreading light than INCs.

CLAIM: INCs cause inserts to sink and warp.
Verdict: Unproven. Never-used NOS playfields often show the same insert issues as routed games. The theory is that the plastic and wood expand and shrink at different rates. However it is true that if an INC is too close to an insert or plastic, it can burn and melt the plastic. This can be easily seen in the pop bumper caps for older games.

CLAIM: LEDs pay for themselves in a few years, in energy savings.
Verdict: It depends. An operator who leaves a game on 24/7 may realize the payback in a few years. For a more typical pin owner, the payback is 10-20 years.

CLAIM: LEDs increase earnings on location.
Verdict (edited): Unproven. Several operators have reported improved earnings (sometimes even doubled), after switching to LEDs. However, more proof is needed that this is true for the majority of locations.

CLAIM: Customers can't change out the LEDs in feature lamps, for Stern pins starting with Star Trek.
Verdict: MOSTLY FALSE. Stern switched from sockets to dedicated lamp PCBs on Premium and LE models, but Pro models still use sockets for all lighting.

Feel free to refute these claims, or any of the claims in this thread, with logic and proof.

And here are a few claims I’d like to explore further. I’ve heard these, but have never seen any proof beyond personal anecdotes (e.g. migraines) or faulty logic (e.g. peeling backglasses). Fact or Myth?:

Heat from INC bulbs causes paint to peel and flake on backglasses.

LEDs can cause seizures, which is why newer Sterns come with a warning on the apron.

Black lights (whether LED or INC) can cause playfield paint to fade, because the light is concentrated at the UV end of the spectrum. [EDIT: some discussion here... https://pinside.com/pinball/forum/topic/black-light-uv-leds-and-lights-does-it-lead-to-fade ]

I bought sampler kits from Comet and Cointaker. I'll take some pics to show why I think this myth should be "busted".

I'm tempted to use my own anecdotal "evidence" regarding INC heat and peeling backglasses, but I don't think I'm typical since my games are rarely on for more than 2-3 hours at a time. None of my "good" backglasses have shown any signs of paint failure (with #44 lighting), but they haven't been on as long as games on location.

Fair enough! I'll just post what I'm seeing. Although when I say "light spread" I'm speaking of both the dispersion *and* the distance that's covered by the light.

No damage yet on my 2004 (HUO) LOTR. In fact the only insert I see any issues with is the large "Rings" insert with all the small LEDs.

Thanks - I changed this to "unproven". It would be interesting to see a poll of ops.

I definitely have some legwork to do. Agreed, citations are important.

Is the Basement lit by #47s or 1st-generation LED bulbs?

Thanks, I've been asking around and couldn't get a straight answer. Will update the original post. Myth busted!

How about this one?

CLAIM: INCs can cause playfield plastics to warp

I've seen plenty of warped plastics, but did heat cause this, or mechanical stress?

Personally, I'm considering this a "myth" for now. I've put CPR plastics on a bunch of my pins, with #44 bulbs under them. I haven't seen any signs of problems yet. I may do a long-term test on a game that's in the restoration queue (e.g. leave it on for several weeks).

What's crazy? Doubting that bulb heat is what causes plastics to warp? I'm just skeptical, I need proof.

That's not surprising, but hopefully it doesn't happen too often. I'm pretty set on sticking with INCs for flashers.

I propose a new term for us incandescent fans who are LED-curious: "biluminous".

There's nothing unscientific about being skeptical about "common knowledge". Please use scientific evidence to prove that I should be worried. I've shopped at least 30 older pins, and although I've definitely seen plastic burned by bulbs that were too close, that doesn't automatically mean that warped plastics with no visible heat damage were warped by heat.

I'm just wondering if there's not a False Equivalence here:

Heat can be used to bend plastics
Bulbs give off heat
Therefore if the plastic is bent, the heat from the bulb must have done it

The experiment I want to set up is to have a game turned on 24/7 for 3 months, with LEDs on one side and INCs on the other. I usually add washers to move the plastics up a bit, but I won't for that experiment.

Almost every old SS pin I've bought had heat damage to the pop bumper caps. It's not surprising, since the bulb is touching the plastic in many cases. Fortunately there are lots of LED options there, since the naked bulb isn't visible.

BTW, I save all my old burned pop bumper caps, in case someone 20 years down the road wants to buy them to make his game look "more authentic". Stranger trends have happened.

RFM has "Martian Hyno-Beam". But, no seizure warnings on my RFM.

Michigan, close enough.

I'm definitely more concerned about this than I am about plastics. If a plastic warps, I can straighten it. But if an insert separates or sinks, it's nontrivial to fix it.

I hope people understand why this topic really needs an evidence-based approach (and my first post was probably a bad first step). There are a lot of people who think that the concerns about INC bulbs are a result of over-hyped LED marketing (try to find RGP conversations about these problems prior to 2008). Conversely, a lot of LED aficionados believe that LEDs are worth the time and effort. I really just want to separate fact from fiction. And frankly, I think both sides are a bit biased. There's a lot of money at stake.

I do believe in the concept of an "expert witness". For example, if someone like Vid or Chris from HEP tells me that I absolutely should not put #44 bulbs under my plastics, I'm going to listen. The rest of you, I'm going to be very skeptical of unless you supply proof.

If you think "LEDs suck" or "incandescents suck", you should probably drain this thread.