Visual difference in emission material when project got upgraded to 23.4

On this project Im working on we have a strong emssion material that gives a lightsaber esque look to it but when we made the jump to 23.4 its no longer has that look as you can see the example. I tried boosting the emission more to no avail and tried switching to lumen but that didnt work either though maybe theres an option/setting i missed. Any advice is appreciated thanks