Thanks, Bo, Dave, Lance, Brez and anyone else responding to this.
Your points are well made and well taken. I agree that I need to discern precisely (as may be possible) when in the history of this aircraft it is being shown in the respective photographs.
It was Dave's wonderful profile (and thanks for posting it again Dave) that got me considering this subject. I like the red.
When I saw Jim's profile's in Bronnenkant's book I also thought at first it was a printing error. But it appears twice; on p.92 when Voss was at J5, as you have shown, Bo, and prior to that on p.87 when Voss was at Jasta B. I feel sure that such an error, if it is one, would have been picked up at the proofing stage of publication. If someone who knows Jim can query him on this I would be appreciative.
And, as pointed out that radiator header tank on the J5 version is a little different than the usual. I'll have to dig up a clearer photo of such an arrangement. Looks like I might be in for some scratch building on the Eduard 1/48 kit I am currently doing.
Now you've got me started! I'm also frustrated that the available decals for this 'plane generally show the bow on the wreath as a very light blue, although on all the profiles and photos it appears darker than that (notwithstanding the vagaries of photos of the era). Also, decal designers don't show the port side and starboard side bows as being slightly different, either (see Bronnenkant p90-91).
I do have the old Glencoe kit's Scalemaster decals which has the bow as darker blue, but the turtledeck heart is the same size as the fuselage heart when cleary it was larger and also had a wider white outline.
Don't get me going on Venetian red!
Cheers
Syd