Hello Dave
fancy seeing you here
I did post a response to this over on Britmodeller , where there is a thread on a new findings on RLM83
http://www.britmodeller.com/forums/index.php?/topic/234939571-rlm83/In regard to the Spitfire, the rudder is a VVS repaint, but it seems to have been standard British practice to paint out national markings and apply red stars to lend-lease aircraft.
This is why Hurricanes and Spitfires etc tend to have upperwing stars, but not on the fin, even though this was not usual VVS practice. Have a look through the lend-lease section, there are some very interesting threads there.
The reason why this got quoted is....because of a posting on the Luftwaffe Experten Message Board [LEMB]
http://www.luftwaffe-experten.org/forums/index.php?showtopic=9035&hl=note post #57
as the site is for members, I'll quote the relevant post.
This is the last news regarding RLM83 Dunkelblau from Kjetil ?kra and Erik Pilawskii recently visit to Stavanger on the He115.
Regarding M. Ullmann?s RLM83 Dunkelblau we also examined the paint on the Bv138 float at Stavanger. Our findings are also in the report and it is clear to us that this is a new dark blue colour. We suspect it was much more prevalent on maritime Luftwaffe aircraft from late 1943 to the end of the war than is currently known. A sample of the paint was not taken. Pursuant to earlier research conducted by notable Luftwaffe historian Michael Ullman, we believed that this paint represented physical evidence of Ullman?s recently described RLM83 Dunkelblau (Maritime). However, upon returning home I discovered that sufficient quantities of this paint were still to be found on my sandpaper so as to enable me to conduct a Ph test. This was done, and the result was conclusive: 7.6. I am convinced that this is the world?s first recognised surviving sample of RLM83. Mr Ullman will be contacted by Kjetil and myself and we will update this investigation as it proceeds.
my response
a pH test on paint, gives a reading of 7.6, proves it's mildly alkaline?
http://en.wikipedia.org/wiki/PHwhich doesn't seem to prove anything about the colour to me.
So, is this is this a different kind Ph? if so, what is it? what is the 7.6 reading?
The name 'Pilawskii' in association with paint tends to start alarm bells ringing with me I'm afraid, and as it says 'Kjetil and myself' it must be Mr Pilawskii.
please see -
http://sovietwarplanes.com/board/index.php?topic=1071.0and -
http://sovietwarplanes.com/board/index.php?topic=1351.0The float photos could be a dark blue, or they could be chalked and faded version of 72/73, which are blue hued greens.
A quick look at the chips in the Official Monogram Guide to Painting German Aircraft shows this could easily be a faded and chalked version of RLM72 but without comparison chips or paint chart on the float then who knows.
HTH
T
one of the links is obviously this thread..
response on LEMB
Troy and others. It is really not that diffuicult if you have the entire report! The Ph-test was done to confirm that it had the same properties as other confirmed RLM paints and was not a point from another source. Other properties, chemcial composition and reflectivity back up this finding. So we know the colour on the bluish float is an RLM paint.
As to the hue of this blue paint we found paintsamples that had been hidden under a metal plate and was undeterioriated, which allowed us to give a very good approximation of how this paint appeared. We are still waiting for Mr. Ullmann's comments, but this colour on the float is indeed intriguing.
And Troy, if the name Pilawskii starts ringing alarm bells with you, I would urge you to seek other sources than the forum on a website which has a clear agenda against mr. Pilawskii's findings. And please use some sources whose sources is not solely googling the internet! Let me tell you that Eric has more than 20 years of experience studying VVS and other collurs and he travelled the Soviet Union when it was still the Soviet Union and checked the paint samples on old aircraft and archival material there which are now largely disappeared (i.e. sold!) or unaccessible, respctively, in modern Russia.
And you can check how many of his protagonist who have actually seen samples of the colours they discuss and have scientific experience in interpreeting black and white photography. I'll be none of them know how specific colours behave on the various types of films used by the Soveits during the war. Eric has this experiences as he has studied it for decades.
Kjetil
I don't know if Kjetil read the threads linked here?
Nick Millman, who is a very careful colour researcher makes some points on Britmodeller. Worth quoting as he makes some interesting points.
Posted 05 August 2014 - 05:32 PM
"...explain how the Ph level of a paint can specifically identify it's origin as being that of an unknown paint colour?"
Yes, I'd like to see that explanation too! It sounds like someone might have been using the bromothymol blue lab test pH indicator of 7.6 to make 2 + 2 = 95,879. There is science and then there is weird science.
Underlying corrosion (amongst other things) can alter the pH level of pigment(s) (which is an attribute rather than an identifier) and in fact special pH indicators are now being experimented with to add to specialist paint so that it changes colour to indicate corrosion occurring on the metal beneath the coating strata. Relevant to old floats maybe?
FWIW RLM 72 is a Munsell Blue, RLM 73 a Blue-Green...
Nick
in response to Kjetil's response, I cross posted due to not everyone being an LEMB member
Sorry to be harsh but most of the statements quoted are incredible.
pH levels would not be unique to RLM paint and as explained above are not necessarily constant anyway.
If the chemical composition is known then the pigments should also be identifiable. Pigment identification would be the most important factor to prove an original blue hue.
"...we found paintsamples that had been hidden under a metal plate and was undeterioriated" Being hidden under a metal plate is no guarantee they would not have deteriorated or shifted. An absence of light is not a surety of pristine, original condition and the apparent integrity of a paint surface, even down to gloss, is no surety of its original colour. Did the metal plate provide an air-tight and water-tight seal? What about thermal ageing? Relative humidity? What about hydrolysis and dilational strains?
"...scientific experience in interpreeting black and white photography." The key word there is interpreting.
"...how specific colours behave on the various types of films used by the Soveits during the war." How on earth can that remarkable process actually be verified? It is debated even in situations where the photographer is attempting to control the process with full cognisance of all the elements, film and filter type in use and with a GretagMacbeth Color Checker. It is difficult to see how any control conditions could be applied to account for camouflage paint colours subject to manufacturing variance, weathering and inconsistent illumination conditions.
http://photo.net/black-and-white-photo-film-processing-forum/00bPNU Mitch K, on 05 Aug 2014 - 8:34 PM, said:
Reaction between paint constituents and the metal plate itself cannot be entirely ruled out, I would say. Even if the plate had actually provided a hermetic seal, I would be loathe to say the colour is "original" and unaffected.
Nick, would a chemical analysis (I'm assuming an elemental analysis) tell you the composition? You'd know the proportions of (say) iron, lead, oxygen etc but not what forms they had been in in the original mix. You could extrapolate, but you've seen where that can lead us :lol:
True enough. The composition could still provide clues by extrapolation because the binder and fillers/extenders are usually an identifiable entity and most pigments will have identifiable properties - to a point (e.g. this is not a pigment, this probably is, because you know you are dealing with paint to begin with) - but certainly not as definitive as polarised light microscopy. If you found elements associated with green pigments, say, you might be sceptical that you were dealing with a blue paint. I should be very interested in the composition that pointed towards a dark blue.
An intriguing aspect of the assertion made is how the chemical composition referred to could be used to verify that RLM paints had been used. I have a post-war MAP report on German aircraft paints which indicates the composition of paints was proprietary rather than mandated. In some cases the synthetic resins (for example) were supplied without the paint manufacturer knowing what they were. For example Warnecke and Bohm (who made their own 'Ikarol' lacquers) also supplied their own proprietary synthetic resins Nos 600, 200 and 100M to Herbig Haarhaus in order for that firm to make their proprietary Herboloid lacquers and to Gustav Ruth. Both those companies had different ideas about how the resins were made! I'm not sure how you could be certain of the paint's origin without a really extensive reference catalogue of paint companies and their formulae.
The impression given (and this might be unfair) is that the identification of an 'undiscovered blue' has preceded the evidence being assembled to make the case for it. That might rule out an objective consideration of what it might be other than blue. The desire to be first to find smoking guns and silver bullets has much to answer for. But just to clarify, whilst I see no reason that a blue paint as described could not have existed my concerns are only around the methodology being described for identifying it. I have no preference of outcome and we do not have the full picture!
Nick
Nick Millman, on 05 Aug 2014 - 10:31 PM, said:
True enough. The composition could still provide clues by extrapolation because the binder and fillers/extenders are usually an identifiable entity and most pigments will have identifiable properties - to a point (e.g. this is not a pigment, this probably is, because you know you are dealing with paint to begin with) - but certainly not as definitive as polarised light microscopy. If you found elements associated with green pigments, say, you might be sceptical that you were dealing with a blue paint. I should be very interested in the composition that pointed towards a dark blue.
Nick, this is what I suspected - a little better, in fact. I didn't consider PLM (not my field at all, I'm afraid) but did wonder if FT-IR microscopy might be able to tease things out. I know it works extraordinarily well on comparison work on complex multi-layer structures like paint chips/laminates, to identify separate layers.
An intriguing aspect of the assertion made is how the chemical composition referred to could be used to verify that RLM paints had been used. I have a post-war MAP report on German aircraft paints which indicates the composition of paints was proprietary rather than mandated. In some cases the synthetic resins (for example) were supplied without the paint manufacturer knowing what they were. For example Warnecke and Bohm (who made their own 'Ikarol' lacquers also supplied their own proprietary synthetic resins Nos 600, 200 and 100M to Herbig Haarhaus in order for that firm to make their proprietary Herboloid lacquers and to Gustav Ruth. Both those companies had different ideas about how the resins were made! I'm not sure how you could be certain of the paint's origin without a really extensive reference catalogue of paint companies and their formulae.
But you very much could come up with a "same/different" list, which might be very instructive. The referencelist might not need to be that extensive - if you could identify even a small number of characteristic low-concentration compounds per manufacturer, then modern techniques (LC-TOF/MS comes to mind) could probably address this relatively quickly and easily.
The impression given (and this might be unfair) is that the identification of an 'undiscovered blue' has preceded the evidence being assembled to make the case for it. That might rule out an objective consideration of what it might be other than blue. The desire to be first to find smoking guns and silver bullets has much to answer for. But just to clarify, whilst I see no reason that a blue paint as described could not have existed my concerns are only around the methodology being described for identifying it. I have no preference of outcome and we do not have the full picture!
Nick
Quite. I have seen this with increasing frequency in my job over the last 10-15 years, and I think it's part of "CSI Syndrome", where people expect tiny pieces of sometimes fairly shonky evidence to always produce unequivocal answers in no time flat. I've lost count of the number of times I've had to explain that although we can now routinely do the impossible, miracles are still rare and take time!
Mitch K, on 05 Aug 2014 - 11:04 PM, said:
Nick, this is what I suspected - a little better, in fact. I didn't consider PLM (not my field at all, I'm afraid) but did wonder if FT-IR microscopy might be able to tease things out. I know it works extraordinarily well on comparison work on complex multi-layer structures like paint chips/laminates, to identify separate layers.
PLM is perhaps the most well-established 'standard' method for identifying pigments although Raman Spectroscopy is a more recent and highly effective development. FTIR is complementary to Raman because the latter will pick up vibrations beyond the capability of the former and intensities are different. Also there are different capabilities for FTIR with some limited in band to the point that they won't "see" certain pigments. However many examinations use both and in one case where fluorescence defeated Raman the IR scans were able to reveal some clues. Subjectively those using PLM often seem to have more insight into the way pigments work once the identification is made, probably a legacy trait from its use in art forensics.
Raman is impressive in the way that it is able to provide quite specific pigment identities. The German paints used a variety of blue pigments including synthetic ultramarine (which is a complex sodium sulfate compound), cobalt and even small amounts of anilin blue which is more dye/stain than particle pigment - I have no idea why. Some of the earlier Luftwaffe paints seem more like tinted varnishes which were applied over a brown primer made of zinc oxide, zinc chromate and carbon black but a very successful single camouflage coating was developed using synthetic paints where the only surface preparation to the metal was the application of polyvinyl chloride putty to rivet holes and panels. Herboloid RLM 02 was a complex and sophisticated composition very clearly intended to have anti-corrosive properties and contained chrome green, chrome yellow, a carbon black that had been refined six times ('sechsbrandruss'), a proprietary lead white with fireproofing capabilities and special red and black pastes of obscure purpose. It is also clear that the application techniques and materials for maritime aircraft were quite specific and included specialised anti-fouling coatings. Another clue that 'standard' Luftwaffe practices might not translate to what is to be found on a preserved float.
Nick
I have quoted Nick and Mitch extensively as it gives an insight into what actual into paint can involve, and how complex it can be.
Hopefully this kind of analysis can be done on VVS paints in the future.
