"Class 42 blue livery - query" or "BR Chromatic Blue"

Peter C

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Hello all,
Upon looking at the Videoscene webpage for the SVR Diesels 30 Years DVD, I found that the following image of a Class 42 "Warship" was on the cover.
Class 42 blue.png
Apologies for the poor quality.

Is it just me, or is this a slightly lighter version of the BR blue livery? I was just wondering. If this has already been discussed, please let me know as soon as possible.
If anyone has any photos or info about this engine and livery, also let me know! :)

-Peter
 
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Hello all,
Upon looking at the Videoscene webpage for the SVR Diesels 30 Years DVD, I found that the following image of a Class 42 "Warship" was on the cover.
View attachment 66029
Apologies for the poor quality.

Is it just me, or is this a slightly lighter version of the BR blue livery? I was just wondering. If this has already been discussed, please let me know as soon as possible.
If anyone has any photos or info about this engine and livery, also let me know! :)

-Peter
In the mid 60's before the adoption of BR Rail Blue there were several Warships and Westerns painted experimentally in Chromatic blue with small yellow panels. D831 was an example.
 

Peter C

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In the mid 60's before the adoption of BR Rail Blue there were several Warships and Westerns painted experimentally in Chromatic blue with small yellow panels. D831 was an example.
Thanks very much. I'm interested in this sort of thing so I'll look it up.

-Peter
 

Peter C

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An example can be seen on page 58 of "Looking back at Westerns"
With the limitations of 1960's colour film it is difficult to tell.
OK. Thanks both. Reading up on that thread, it turns out that it was more down to the film used by the photographer and the lighting conditions, rather than a difference in livery.
I'll look up this Looking back at Westerns book. A local heritage line will probably have a copy!

-Peter
 

Alanko

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BR Blue seems to be a tricksy colour to photograph. I went to see Deltic 'Alycidon' in Waverley a few months back (just before it had its incident) and tried to photograph it with my iPhone 8. The camera was not getting the blue right. It was subtly mixing out some of the green element of this particular hue of blue.

Google for models of locomotives in BR blue and you see a whole spectrum of blue being used.
 

Peter C

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BR Blue seems to be a tricksy colour to photograph. I went to see Deltic 'Alycidon' in Waverley a few months back (just before it had its incident) and tried to photograph it with my iPhone 8. The camera was not getting the blue right. It was subtly mixing out some of the green element of this particular hue of blue.

Google for models of locomotives in BR blue and you see a whole spectrum of blue being used.
I Googled for the Chromatic Blue and pretty much every model which came up said it was in this shade. But even a loco which I had thought in model form was BR Blue was said to be in Chromatic!

-Peter
 

Alanko

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I Googled for the Chromatic Blue and pretty much every model which came up said it was in this shade. But even a loco which I had thought in model form was BR Blue was said to be in Chromatic!

-Peter
It is an interesting quandary. When I last visited Bo'Ness there was 27001 chuntering around, in BR Blue with yellow ends. Up close it looked surprisingly rough. Presumably this loco is hand painted? Was this a standard approach, back in the day, or a cost cutting measure for a preserved railway? The paint around the cab has been applied over either a lot of existing paint or a lot of shrunken filler. Presumably it takes too long to take these panels back to bare metal. Note the 'acne' above the window!



Either way, the colour above very close to the Deltic, both locos being much cleaner now than when used in anger presumably, and my iPhone didn't get the colour right. I saw one colour with my eyes and another on screen. IPhone cameras can peep into near infrared; snap a photo of a halogen hob and you will see a purplish glow on screen where there is none in real life. I'm wondering if this is why my phone struggles with BR Blue, and perhaps film cameras struggle as well? I've seen the theory stated before that Chromatic Blue was simply the result of primitive colour film struggling to capture the colour correctly.

Presumably 'Chromatic Blue' could also just be an expertly applied BR Blue over properly prepped metal work, then maybe finished off with a clear coat? From time spent spraying guitars I know that a good finish starts with a properly prepped, flattened surface. You can't spray a thick coat and hope that all the swirls, dents and heavy sanding marks will fill themselves in, or that lots of block sanding will remove the marks once the lacquer is cured. The Bo'Ness 27 looks like thickly applied paint over many previous coats of paint and filler. Would loco finishes of the period just be cellulose paint and thinners, or something a bit harder wearing?

I suppose the next question then is who had the recipe for BR Blue paint? Was it produced centrally somewhere, or was it up to individual sheds to reproduce by mixing stock paints to a known ratio? How well did the paint respond to UV light (if cellulose then not very well). I've seen it mentioned online that Chromatic Blue was metallic, which suggests a sprayed finish (and a nightmare to get the metallic particles to sit correctly so as to appear uniform when finished).

Going right back to the first post, there is a number of reasons as to why the blue might not look right. It looks like a squished and squashed JPEG image, and the blue almost looks doctored to my eyes.



Oh, and the two 50s at the top there look like different shades of blue as well. I think the large logo, white roof and yellow cabs of the left hand loco makes the shade of blue look different. Likewise Finsbury Park Deltics with the white cab window surrounds look different to me. Maybe BR Blue looks different depending on the shape of the loco it is applied to and what percentage of the total area of the loco it covers. Carpet a 42 in it, sparing only some small yellow ends, and it might look quite different!
 

randyrippley

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from https://en.wikipedia.org/wiki/Phthalocyanine_Blue_BN
The substance, chemical name (29H,31H-phthalocyaninato(2−)-N29,N30,N31,N32)copper(II) (or copper phthalocyanine),[2] is also known as monastral blue, phthalo blue, helio blue, thalo blue, Winsor blue, phthalocyanine blue, C.I. Pigment Blue 15:2, Copper phthalocyanine blue, Copper tetrabenzoporphyrazine, Cu-Phthaloblue, PB-15, PB-36, C.I. 74160, and British Rail Blue. Numerous other trade names and synonyms exist.[3] The abbreviation "CuPc" is also used
 

Alanko

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Many thanks for this! It would seem that this blue is very stable as a pigment. I'm wondering if the varying green comes from either a clear topcoat or the substrate the pigment is mixed in with?

Crafmasters Paints (.co.uk) reckon this is BR Blue:



Trainshop (.co.uk) reckon this is BR Blue:



The latter is closer to Bo'Ness' 27 and 20, and the Deltic as well, and it has a lot more green in it. The former is closer to the straight blue pigment you linked to on Wikipedia. I've seen many models of diesel locos sprayed this darker blue colour with less green. Sometimes it is passed off as 'Chromatic Blue' as well.

Taking a look at a photo of supposed Chromatic Blue:



I think it is safe to say that all the colours have drifted in this photo. The platform has a purplish hue to it and the yellow panel is actually made of brown tones. I pulled it up on my laptop and sampled the RGB values of points all over that yellow panel, and there is no yellow left in it!
 

randyrippley

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It was a few years before they found a colour-stable paint formulation, the early repaints faded quickly
Of the two colours you've sampled above, the second is closer to reality but needs to have more colour density and be slightly greener - theres too much white in it. The first is closer to electric blue of the AC locos.
As I said in the other thread, there would be a lot of variables affecting the actual colour:

actual percentage pigment in the paint
spray vs brush
lacquered or not
was undercoat used or was it directly on top of the old green? My memory is that on the Hymeks the old green could be seen through the blue, especially when weathered
 

M7R

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Depending who you speak to some say it’s more green than blue, it does seem to be an odd colour that looks different depending who you ask, lighting etc
 

Peter C

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It was a few years before they found a colour-stable paint formulation, the early repaints faded quickly
Of the two colours you've sampled above, the second is closer to reality but needs to have more colour density and be slightly greener - theres too much white in it. The first is closer to electric blue of the AC locos.
As I said in the other thread, there would be a lot of variables affecting the actual colour:

actual percentage pigment in the paint
spray vs brush
lacquered or not
was undercoat used or was it directly on top of the old green? My memory is that on the Hymeks the old green could be seen through the blue, especially when weathered
Depending who you speak to some say it’s more green than blue, it does seem to be an odd colour that looks different depending who you ask, lighting etc
Interesting.
I know that the lighting conditions can distort the colours of something. The yellow panel on the Western further up the thread does seem to be yellow to us, but as the poster said, it isn't actually. I think maybe "Chromatic Blue" could be defined as BR Blue when in certain lighting conditions, e.g.
"This engine was painted in BR Blue in the workshop at Swindon but now when we see it in Paddington it's in a very nice shade of Chromatic Blue thanks to the lighting here"

-Peter
 

E759

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BR Blue seems to be a tricksy colour to photograph. I went to see Deltic 'Alycidon' in Waverley a few months back (just before it had its incident) and tried to photograph it with my iPhone 8. The camera was not getting the blue right. It was subtly mixing out some of the green element of this particular hue of blue.

Google for models of locomotives in BR blue and you see a whole spectrum of blue being used.
I use an iPhone XR, Canon 80D and Leica M10-P; it appears to me that iOS performs colour processing on the captured image before saving. Colours are often vivid with the resultant image “better” than real life.
 

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Looking at some old colour slides taken in the 70's
Kodak Ektachrome seemed to have odd colour variations particulaly with artifiical light.
 

randyrippley

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you also have to take into account weathering, dirt / oil fumes / smoke ........
as I said in the other recent thread, when applied to the Sealink ships it really did look green.

But thinking about it, I have a theory that the colour actually drifted and became less green with subsequent repaints - the earlier versions of the paint is said to have been unstable, maybe the truth is that the early iterations of the paint formula faded to a greenish shade? Later versions stayed blue?
 

Alanko

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I use an iPhone XR, Canon 80D and Leica M10-P; it appears to me that iOS performs colour processing on the captured image before saving. Colours are often vivid with the resultant image “better” than real life.
Interesting that you mention that, as I think I've observed the same thing. I was selling a Magimix blender recently, which was in this fetching shade of teal:




My iPhone was correcting the shade of blue to a much bluer hue, with far less green in the mix. When I downloaded the photos onto my laptop my photo editing software (Cyberlink PhotoDirector) initially opened the photos with the correction applied, and then instantly reverted them back to their initial state. As such the teal colour jumped back to life.


Depending who you speak to some say it’s more green than blue, it does seem to be an odd colour that looks different depending who you ask, lighting etc

This was why I was asking if BR Blue was a colour mixed at various depots, using a standard recipe. This is how Spitfires were painted during WW2, and the odd colour 'sky', painted on the underside, was quite different depending on whether it was a Castle Bromwich Spitfire (etc). The colour 'sky' upsets the scale model guys immensely, as it doesn't have any blue in it, and various paint companies produce different hues. There is a later British Standard colour 'sky blue' (BS 381c 101) that is entirely different, and is the colour that the engines in military vehicles were repainted in once they had been overhauled back in the '60s. Go into the archives at the RAF museum at Hendon (I think?) and there are original paint swatches that some consider to be definitive, but who knows how well these have aged and decomposed over time.

On a slightly similar note I've also heard about modelers going to the de Havilland museum to capture the proper shade of yellow of the prototype Mosquito. From memory somebody was very smug about getting the colour right, but elsewhere on the aircraft the yellow paint had worn away to reveal a different shade of yellow. The correct yellow was the lower layer, that had been over-painted with some sort of car paint during an earlier restoration. It isn't easy getting these colours right!

I also don't think it is unreasonable to say that it is mostly men who are interested in this stuff, and colour blindness of various forms is more prevalent in men. I use this website sometimes to check that any graphics I produce for work still make sense for colour blind people. https://www.color-blindness.com/coblis-color-blindness-simulator/

I uploaded a recent photo of the Deltic 'Alycidon', resplendent in BR Blue, and toggled through the options. If you simulate 'Green-Weak/Deuteranomaly' then you wind up with a colour close to the deeper BR Blue that some modelers use! Coincidence? A good number of us edit our photos digitally (in my case usually to try and squeeze something acceptable out of marginal quality raw ingredients), so it is no wonder that BR Blue is such a slippery fish really.

Interesting.
I know that the lighting conditions can distort the colours of something. The yellow panel on the Western further up the thread does seem to be yellow to us, but as the poster said, it isn't actually. I think maybe "Chromatic Blue" could be defined as BR Blue when in certain lighting conditions, e.g.
"This engine was painted in BR Blue in the workshop at Swindon but now when we see it in Paddington it's in a very nice shade of Chromatic Blue thanks to the lighting here"
This is what I'm thinking at this stage. I think the finish gets a helping hand from being applied to bare metal, rather than slopped on top of another finish (like the Hymeks mentioned in this thread), patched in and reapplied over a rougher surface. Ask anybody who resprays or details cars and they will tell you that if you want an optimal finish then the car needs to be taken back to bare metal, primed and sprayed after that. Of course you can simply key up the factory finish, fill up the rusty areas with body filler, level everything with 120 grit paper and then crank out the Halfords aerosols! As a finish it will work to keep the corrosion at bay and give an approximately consistent colour that looks passable from ten feet away. Likewise you can spend more time properly flattening out the finish on your car and achieve a level finish that is superior to what left the factory (some Ford Mustang restorers aim to copy the inferior 'orange peel' look of the rushed, original '60s finishes on these cars).

I think that Chromatic Blue is therefore BR Blue 'on a good day', painted on properly prepped surfaces with a high level of care an attention. I sincerely doubt they were finishing locos using metallic paint or anything else like that.
 

Peter C

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This is what I'm thinking at this stage. I think the finish gets a helping hand from being applied to bare metal, rather than slopped on top of another finish (like the Hymeks mentioned in this thread), patched in and reapplied over a rougher surface. Ask anybody who resprays or details cars and they will tell you that if you want an optimal finish then the car needs to be taken back to bare metal, primed and sprayed after that. Of course you can simply key up the factory finish, fill up the rusty areas with body filler, level everything with 120 grit paper and then crank out the Halfords aerosols! As a finish it will work to keep the corrosion at bay and give an approximately consistent colour that looks passable from ten feet away. Likewise you can spend more time properly flattening out the finish on your car and achieve a level finish that is superior to what left the factory (some Ford Mustang restorers aim to copy the inferior 'orange peel' look of the rushed, original '60s finishes on these cars).

I think that Chromatic Blue is therefore BR Blue 'on a good day', painted on properly prepped surfaces with a high level of care an attention. I sincerely doubt they were finishing locos using metallic paint or anything else like that.
Interesting. Given the number of engines BR would have had to paint it's not unforgivable that they painted some in a slightly off shade. Here though some means 99%! :)
I wonder if chromatic blue will be more prevalent on heritage lines than on the national network back in the day as these lines have more time to give to each engine?

-Peter
 

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Interesting. Given the number of engines BR would have had to paint it's not unforgivable that they painted some in a slightly off shade. Here though some means 99%! :)
I wonder if chromatic blue will be more prevalent on heritage lines than on the national network back in the day as these lines have more time to give to each engine?

-Peter
One of the preserved Peaks has been painted in a version of small yellow panel BR blue, but to my eyes it doesn’t look right especially in the flesh, although I don’t remember them in that livery anyway so I’ve got nothing other than photos to compare it with...
93574C2D-2718-4E6C-B8B6-45001A2F2A26.jpeg
(46045 taken by Tom Curtis)
 

Edders23

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from what I was told a few years ago by someone who was involved in the BR engineering set up in the 60's although there was a specification for monastral or rail blue it varied between works and depots depending on the source of supply until the late 60's I think when a single source of supply was used for all.

I am sure i read somewhere that there was a different shade known as monochromatic blue tried first which was rejected in favour of the rail blue but only applied to a limited number of locos
 

Peter C

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One of the preserved Peaks has been painted in a version of small yellow panel BR blue, but to my eyes it doesn’t look right especially in the flesh, although I don’t remember them in that livery anyway so I’ve got nothing other than photos to compare it with...
View attachment 66296
(46045 taken by Tom Curtis)
That definitely looms a bit too bright to be BR Blue. But the 45 looks lovely in that livery! I saw 45149 at the GWSR Diesel Gala today and it was in a more "standard" (darker) BR Blue livery.

-Peter
 

Alanko

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Interesting. Given the number of engines BR would have had to paint it's not unforgivable that they painted some in a slightly off shade. Here though some means 99%! :)
I wonder if chromatic blue will be more prevalent on heritage lines than on the national network back in the day as these lines have more time to give to each engine?

-Peter
An interesting thought, using my pet definition of chromatic blue :wub:. On the one hand heritage locos can be babied more I presume, but they are also limited to what these guys really have the time and resources to do. A lot of heritage lines seem to have diesels under overhaul for long periods of time, so I wonder if the cosmetics come in second place? Judging by my photo of Bo'Ness' 27001, there is a lot of filler trussing up the rougher sections around the cab. I wonder if the guys at Bo'Ness can do anything but brush-paint locos. You would need a pretty hefty respirator setup, and ability to isolate the loco, if you were to properly strip it back to bare metal. You probably can't just let the apprentice have a bash with a random orbital sander! I'm not sure which heritage railways have such facilities, or whether somewhere like Crewe heritage centre is setup for this sort of work? I assume it comes down to money (and me not really knowing how engines are painted and assuming they are painted like cars).

One of the preserved Peaks has been painted in a version of small yellow panel BR blue, but to my eyes it doesn’t look right especially in the flesh, although I don’t remember them in that livery anyway so I’ve got nothing other than photos to compare it with...
View attachment 66296
(46045 taken by Tom Curtis)
That looks nice, but it is a vivid colour! There doesn't seem to be enough green in the mix, to my eyes? Presumably modern paints are formulated to hold their colour better and not yellow, so maybe the heritage guys need to start applying a yellow'd clear coat over the blue to get us back to the appearance of weathered '60s locos? Maybe spray on a bit of dirt, dust and dead flies at the same time? :p

from what I was told a few years ago by someone who was involved in the BR engineering set up in the 60's although there was a specification for monastral or rail blue it varied between works and depots depending on the source of supply until the late 60's I think when a single source of supply was used for all.

I am sure i read somewhere that there was a different shade known as monochromatic blue tried first which was rejected in favour of the rail blue but only applied to a limited number of locos
That is very interesting to hear, thanks.
 

Peter C

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An interesting thought, using my pet definition of chromatic blue :wub:. On the one hand heritage locos can be babied more I presume, but they are also limited to what these guys really have the time and resources to do. A lot of heritage lines seem to have diesels under overhaul for long periods of time, so I wonder if the cosmetics come in second place? Judging by my photo of Bo'Ness' 27001, there is a lot of filler trussing up the rougher sections around the cab. I wonder if the guys at Bo'Ness can do anything but brush-paint locos. You would need a pretty hefty respirator setup, and ability to isolate the loco, if you were to properly strip it back to bare metal. You probably can't just let the apprentice have a bash with a random orbital sander! I'm not sure which heritage railways have such facilities, or whether somewhere like Crewe heritage centre is setup for this sort of work? I assume it comes down to money (and me not really knowing how engines are painted and assuming they are painted like cars).
I don't know anything about how trains are painted, but I would say (going based on what others here have said) that to achieve the best results from BR Blue a locomotive must be completely stripped back to the bare metal, covered with some sort of an undercoat, and then painted with the BR Blue. I doubt very few heritage lines actually have a dedicated place to do this in the way they'd like to. The Class 47 in the diesel shed at the GWSR Diesel Gala today was painted in BR Blue but with some patches of very light blue which didn't look like any sort of BR Blue - more like some sort of light undercoat maybe?
Like many things on heritage railways, it is money that is the issue. I'm sure that everyone at every heritage railway line across the country would love to have a dedicated painting shop, double tracks, more engines, etc., but due to this thing called money it can't happen - unless people get involved and donate money!

-Peter
 

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Electric Blue? Excuse me for being stupid, but is that a BR colour for electric locos or a shade of blue? Sorry.

-Peter
Electric Blue is what the AC electrics AL1 - AL6 (now known as classes 81-86) were delivered in when new.
Here’s a useful picture (not mine) showing the difference in shades.
88B08CBB-1CE6-4297-8DD3-5A199D5CEE7F.jpeg

Obviously these are from the preservation era so they may not be completely correct, but Peter may have a point there regarding the 46.
(This all confuses me and I’m a painter :lol:)
 

Peter C

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Electric Blue is what the AC electrics AL1 - AL6 (now known as classes 81-86) were delivered in when new.
Here’s a useful picture (not mine) showing the difference in shades.
View attachment 66314

Obviously these are from the preservation era so they may not be completely correct, but Peter may have a point there regarding the 46.
(This all confuses me and I’m a painter :lol:)
Interesting, thanks.
I think that at the moment, from what has been said on this thread, we can define BR Chromatic Blue as being:

"A shade of blue which was applied to British Rail locomotives and was, through either the method of painting used, or the lighting conditions when observed, different in some form or other to the 'standard' British Blue blue. Chromatic Blue is often a lighter colour of the BR Blue but is slightly darker than the BR Electric Blue."

I think that Chromatic Blue is probably just the result of either:
-Rushed painting of locomotives (not stripping back to bare metal, just painting over an existing colour)
-Different colours of paints between depots (I assume that back in BR days, and correct me if I'm wrong, it would have been a bit difficult to ensure that every depot had the same shade of BR Blue; maybe now it's easier?)

I've just quickly put this little thing together in Photoshop, using the images which have been put up on this thread:
Untitled-5.jpg
And I think this shows the differences in the colours shown. I tried to sample the best pieces of the liveries, with areas out of direct sunlight being the best.

-Peter
 

Alanko

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Thanks Peter for putting all these photos together in one place.

I took this image from Wikipedia:



...and had a plitter around in image editing software:




These old photos seem to shed a lot of their green 'data' and develop a sort of purple/blue imbalance.

Is this what Class 40s looked like back in the '60s?
 

Peter C

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Thanks Peter for putting all these photos together in one place.

I took this image from Wikipedia:



...and had a plitter around in image editing software:




These old photos seem to shed a lot of their green 'data' and develop a sort of purple/blue imbalance.

Is this what Class 40s looked like back in the '60s?
You're very welcome!
You know what, that Class 40 with the edits applied looks a bit like the Tri-ang Class 37 in BR Blue I have for my model railway!
The original photo makes the day look so much more bleak and colourless; I think your edits make it so much better. If we could somehow contact the photographer and see if he/she could remember what that day was like, we could edit that photo and make it so much better. Maybe digital photos and cameras will mark the end of any confusion about Chromatic Blue and we can be more sure that the blue used is closer to standard BR Blue?

-Peter
 

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