I fully accept Mark's comments on colour film reproduction, printing, different light and even the effects of pollution. As is also well known, individuals eyes perceive colours differently. However, having said all that, there is a distinct difference in shade between the original blue and the later Rail Blue used on the AL6.
I have spent quite some time observing electrics on the WCML, which I live near and yes, the AL6's were not Electric Blue as the earlier AL1-5's. The difference between shades became marked once the 86's started to be repainted into Corporate Blue using the darker Rail Blue. Of course, the original blue had faded a bit by this time! I must add that these observations were made at all times of day, in different lighting all year round, but such are the joys of commuting!
My concern was that Heljan might have produced an as built AL6 in the wrong shade, which would have been a shame.. But, seeing as Ben is involved and is fully aware of the problem and is researching into original paint codes with the AC Electric Group, I think we will be as near as possible.