There's no doubt that capturing accurate digital photos of light itself is very tricky. I've been making decent attempts for several years as a custom flashlight collector. The biggest roadblock is the reduced dynamic range of most digital cameras. They simply can't handle the dynamic range that the human eye is capable of seeing. Digital-back medium frame cameras such as Hasselblads and pro-level DSLRs with full-frame sensors are far better that consumer grade cameras, but they're also quite expensive.
The poster on the other forum did a fairly good job of working within the limitations of a consumer digital camera, but there is some room for improvement. For example, he used manual exposure to insure that exposure was the same across the series of photos. Unfortunately, blown highlights and blooming in the first lume photo reveal that he overexposed the entire series, making everything appear too bright. Some would argue that doing so may make the images look more accurate when compared to what the eye sees. My view, however, is that when you are attempting to capture accurate brightness levels, you must start with a correctly exposed image for the brightest scene to be included and let everything else fall within the camera's dynamic range as it may and hope for the best. Overexposure and a potentially changing white balance explain the misleading color change in the first photo (white instead of blue). Overexposure and reflected light explain the non-distinct edges (blooming).
If there's interest, I can attempt to do a similar set of correctly exposed images for my two Breitlings - a 2006 Blackbird and a 2010 Aerospace. I could also include a 4 year old Marathon Navigator to provide a tritium-based steady state reference that should fit nicely within the brightness ranges of my Breitling's SL. Just be aware that, if I do this, folks will need to download the photos to their computer, turn the brightness down as much possible and wait in a dark room for night vision to fully develop. This would take about 20 minutes. If folks just try to view the photos in the thread in a normally lit room, the photos towards the end of the series would appear very faint, just like the Seiko Monster was in the last image on the other forum.
As reference, there's a recent lume shot of my Aerospace in
this thread. And
this one shows how the limited dynamic range of digital cameras can give reasonably accurate representations of varying brightness levels. I'm definitely an amateur, but I think I can get the job done.