Blue, Blue, My Love Is Azure Blue - and happily some of our paints are too 😀

[Nick Millman]

Hi John

The closest I can get using Humbrol is with their brightest blue which is 14 Gloss French Blue. The mix is approximately 12 white, 4 blue and 1 red (in this case 153 Matt Insignia Red) but there is a caveat in that I have no Humbrol matt white and had to use Revell satin white (301) instead! I have no idea if Humbrol matt white would produce a slightly different result. Using the gloss gives the bonus that is is very nice to brush paint. I'll measure it later and see how far off it is.

I haven't tried the 25 Matt Blue but suspect it may make the mix too grey.

As an aside I like to use Humbrol gloss primary colours in mixes (with matt and satin) when I can because they aid brush painting significantly being very smooth and levelling well.

Nick

Update: Measured the Humbrol mix described here - 3.4 PB 5.9/5.2 compared to RAF Museum chip 4.1 PB 6.2/6.0. Difference calculation is 3.40 where < 2.0 = a close match. In the photo it looks less similar than it actually appears to the eye. The RAF Museum chip is still slightly brighter but so far none of the hobby paints captures this degree of brightness.

Edited July 7, 2010 by Nick Millman

[Nick Millman]

I measured the chip of ANA 609 (US) Azure Blue and it is 3.1 PB 5.2/4.9 compared to RAF Azure Blue's 4.1 PB 6.2/6.0, a difference calculation of 9.48 where < 2.0 = a close match. The caveat is that the cracking of the surface may have compromised the accuracy of the measurement. However, in comparison to FS595B the closest match is still 35231 @ 3.52 which accords with most sources.

The US colour is a deeper, "cooler" blue and comparing it with Xtracolor the difference is 5.84 which suggests that paint may have been matched to ANA 609 rather than to the RAF Azure Blue. On the other hand, checking my old Kittyhawk the Xtracolor Azure Blue I used on that (from the same tin) is closer to the RAF Museum chip than the swatch I brushed out a few days ago so I have a sneaking suspicion that the Xtracolor paint may have become darker with age in the tin. I did think this might have happened once before with a tin of RAF Trainer Yellow.

In the photo below the only Azure Blue on the model retaining its original colour is a narrow strip either side of the centreline - barely visible on the photo but best seen on the inboard edges of the flaps. It is quite different to the swatch of the same paint from the same tin brushed out a few days ago. The rest of the paint on the model has become cooler and greener although there is a deeper blue patch behind the starboard wheel well (to the left on the photo)

Nick

Edited July 7, 2010 by Nick Millman

[Kes]

For what it's worth I've painted out some samples, and Humbrol Authentic Azure Blue is a little brighter and bluer more like PRU Blue compare to Hu157 which is more like a bluish Dark Sea Grey, which might just do for FFA Blue Grey used as used on 70's Navy Helicopters

. . . Kes

[stevehnz]

Here's what I got when I tried the mix mentioned by Edgar and Steve:

The result is lighter and brighter than either of the Hannants shades, so heading in the right direction. Compared to the RAFM chip (and acknowledging Nick's points above!) it still looks too grey and not violet enough to me.

This is obviously an elusive shade. I'm wondering if Humbrol white plus 25 Blue is the correct way to start, I'm not sure 25 is strong enough.

John

John, your last comment is interesting. Something I'd forgotten till I read it is that when I first tried this I didn't have any H25 so ended up using some H14 French Blue which is quite a lot more vivid. This is what the wee Spit in the pic in my first post is finished in. The fact it was brushed over a coat of H89 Middle Blue lead me to believe this had made it bluer than subsequent mixes but its worth trying with H14 perhaps.

Nick, thanks for the links & info on the Munsell system, I've some reading to do though I still reckon I'll fall back on the TLAR system, perception & interpretaion are very important but its nice to have some science as a start point.

Steve.

[Prop Duster]

...one of the reasons I don't trust visual matches (there are other reasons too) - and no offence to anyone is intended or should be taken - but prefer instead to number crunch the tristimulus values, the chromacity coordinates and the CIE LAB values! Nick

Nick

Very commendable and scientific and no doubt the most accurate method currently available.

I'm sure we general modelers will go to a favored brand of paint and mix in additional colors, as you allude, "until it looks right to me". But just knowing that there is work/results available for a "true" color match, is worth having for those occasions where extreme accuracy is needed.

Now the question; What will it take, to get your kind of results, incorporated into the manufactures paints?

Giving us, the general population, a product both accurate and more uniform from most, if not all, manufactures. Even if they should have to -gasp!- change their current formulations and perhaps -shudder!- change the names (ie the 2 azure blues) to be more relevant to our needs.

Thanks again for you enlightenment

= me waiting for those changes to happen

[Mark M]

can i just add the citadel blues to the mix, there is one of a very simlar colour, im at work so cant do a cip at the moment but will when i can

[cdk]

I measured the chip of ANA 609 (US) Azure Blue and it is 3.1 PB 5.2/4.9 compared to RAF Azure Blue's 4.1 PB 6.2/6.0, a difference calculation of 9.48 where < 2.0 = a close match. The caveat is that the cracking of the surface may have compromised the accuracy of the measurement. However, in comparison to FS595B the closest match is still 35231 @ 3.52 which accords with most sources.

The US colour is a deeper, "cooler" blue and comparing it with Xtracolor the difference is 5.84 which suggests that paint may have been matched to ANA 609 rather than to the RAF Azure Blue. On the other hand, checking my old Kittyhawk the Xtracolor Azure Blue I used on that (from the same tin) is closer to the RAF Museum chip than the swatch I brushed out a few days ago so I have a sneaking suspicion that the Xtracolor paint may have become darker with age in the tin. I did think this might have happened once before with a tin of RAF Trainer Yellow.

In the photo below the only Azure Blue on the model retaining its original colour is a narrow strip either side of the centreline - barely visible on the photo but best seen on the inboard edges of the flaps. It is quite different to the swatch of the same paint from the same tin brushed out a few days ago. The rest of the paint on the model has become cooler and greener although there is a deeper blue patch behind the starboard wheel well (to the left on the photo)

Nick

Hello Nick and all,

in the Monogram USN and Marine Corps Colour guide Vol. 2 is a Munsell notation for ANA 609 with 5.3PB 5.36/6.35. compared with FS 35231 wich is 5.6PB5.4/6.4. Is your ANA chip from that book or is it a original ?

This all is very interesting for me. A other question. Is there a difference between DuPont 71-062 and ANA 609 ?

Claus

[Nick Millman]

Hello Nick and all,

in the Monogram USN and Marine Corps Colour guide Vol. 2 is a Munsell notation for ANA 609 with 5.3PB 5.36/6.35. compared with FS 35231 wich is 5.6PB5.4/6.4. Is your ANA chip from that book or is it a original ?

This all is very interesting for me. A other question. Is there a difference between DuPont 71-062 and ANA 609 ?

Claus

Hello Claus

Mine is an original swatch of paint and the value I recorded for 35231, measured from the chip in L*a*b* and converted, was 4.8 PB 5.4/5.7. The book you refer to uses the word "determined" rather than "measured" and in a footnote uses the worrying phrase "visually determined" so I wonder if the Munsell Book of Colour was used for visual matches. Without L*a*b* values the Munsell values provided have to be taken on trust. But to put it into context the difference between the two quoted values is 4.48. Note also what I wrote about the cracked and chalked surface on the ANA 609 sample which may have compromised the accuracy of the measurement.

To appreciate the step changes go here:-

Munsell Colour System

In the first chart, under "Hue", the colour immediately to the left of the one marked "5 PB" (which is 5 PB 6/6) is 2.5 PB 6/6 but note the relative difference between the two. In the third chart lay your cursor on the different squares around 5 PB 5/6 and 5 PB 6/6 and you will get an idea of the tolerances involved.

I don't have a swatch of Du Pont 71-062 except on the Du Pont Colour Standards card. It looks exactly similar to the RAF colour and of course it preceded ANA 609.

Nick

[John]

I was in Edinburgh yesterday afternoon, so I dropped in to Wonderland Models to pick up a newer tin of AB. Of course, I have no way of knowing how long this particular tin has been in the shop, but I think I'd be safe in assuming it's of a more recent vintage than my original sample. These are the 2 tins together, the older on the right:

What did surprise me was the result of the brush-out. The new Xtracolor is darker and greyer than the older one:

The best visual match I could get against FS595 was 25177:

although the paint is more blue than the chip. RAL 5009 is, interestingly, close but bluer. The closest Pantone I could get was 7468.

Curioser and curioser, said Alice!

John

[cdk]

Hello Nick,

thank you for the explanation. it is good to know that DuPont and AM Azur Blue are looking the same. Up to today I was thinking Dupont and ANA Azur Blue are close. With this in mind, the pictures on page 301 and 302 in Air Arsenal North America and on page 108 and 109 in Royal Air Force of WWII in Colour shows Kittyhawk III with a dark blue underside. Is it possible that this a factory desert scheme with DuPont 71-063 Light Med. Blue? The caption in Air Arsenal North America says the picture are taken in April 1943. ANA came in use after September 1943. So it is to early for the darker ANA609. But this is stuff for a discussion about the Med. Blues.

Best Regard

Claus

[John]

I've been able to add WEM's interpretation to my ever expanding collection of Azure Blue paints. Here is their swatch compared to the others:

It's the lightest of the paints I have, but to my eye still lacks that distinctive violet quality that fresh AB should have:

Still, probably a toss-up between this and Xtracrylic for the best from the pot so far.

John

[Nick Millman]

Interesting. The colour really is like the bright blue of the sky and has been mixed by artists from time immemorial. Unfortunately just adding white to the paints isn't the answer in this case. The demonstrated hobby paints replicate neither the hue nor the brightness of that colour, they are all too grey and too dark. I had thought Xtracolor was the best but it now seems there is no truly representative version of Azure Blue available out of a tin - or bottle. Anyone know what the Testors and/or Pollyscale are like?

Pedantry aside, this is an example where the essential character of a colour has not been achieved and good enough is not good at all.

Nick

[Edgar]

It might pay to check on Precision Paints (now known as Phoenix Precision Paints); they dropped a/c colours, but have reintroduced a range, and I know that the owner prides himself on trying for utmost accuracy.

Edgar

[Stoo]

Link for Edgar's post for the lazy: http://www.phoenix-paints.co.uk/enamel.asp?F_Railway=80

Interestingly enough, Tamiya's new Spitfire Mk.VIII has a colour which looks pretty close from an initial glance (Obviously there are probably issues around colour accuracy over the web from disparate sources) : http://www.tamiya.ca/6-70000%20series/60320_24.jpg & http://www.tamiya.ca/6-70000%20series/60320_30.jpg

[John]

It might pay to check on Precision Paints (now known as Phoenix Precision Paints); they dropped a/c colours, but have reintroduced a range, and I know that the owner prides himself on trying for utmost accuracy.

Edgar

Maybe after pay day!

John

[John]

I've sent off an order for Precision Sky and Azure, which should just about be it for paints easily available to the UK market. We'll see how they compare when they arrive.

I also went in to my local Games Workshop yesterday and had a look at what they have. None of their line of blues looks like an off the shelf solution for AB, but I did pick up a pot of Enchanted Blue, which looked to be the strongest blue in their range. I'll do some experiments with it to see if I can get near the RAFM chip. I'm pretty sure GM and Humbrol acrylics are one and the same, so there shouldn't be any problems mixing the 2. Mind you, with GM charging £2.35 for 12ml, I'll stick with the other models paint brands!

John

[Mike S]

I decided to do a little experiment this afternoon to see if I could prove a pet theory, which is that Humbrol inadvertently matched the wrong standard when they brought out their Authentic Azure Blue in the 1960s, and the wrong shade persists in the current Humbrol 157.

When BS381 was first issued in 1930, Colour No 4 was listed as Azure. It's a strong dark blue, lighter than Oxford Blue and not a great deal different from the current Roundel Blue. Subsequently, the Royal Aircraft Establishment created the bright blue Desert Scheme colour we are familiar with as Azure Blue - similar name but completely different shade! It had occurred to me to wonder if Humbrol had matched the wrong Azure, not realising there were 2 shades with more or less the same name. There is another theory that Humbrol matched their paint against Light Mediterranean Blue, rather than Azure Blue.

I looked out the oldest tin of Azure Blue I could find in my paint box, which is an early version of 157 rather that the authentic HB13. and since it is a "blue stripe" tin probably dates to when 157 was introduced to the Standard range, which Richard Humm dates at 1988 in his list on the Airfix Collectors Forum. This colour was brushed out and compared to the chips in the RAF Museum book:

It looks nothing like Azure Blue, as we know, but it's also not that close to LMB either. LMB is bluer and less grey than 157. 157 is also markedly darker and greyer than the current BS381c-104 Azure, so it looks like both these theories are wrong at least based on this particular incarnation of 157\HB13. We're still no wiser when it comes to what Humbrol were thinking when they introduced this shade!

Comparing 157 to FS595, the nearest match is 35164:

Turning to the chip of AM Azure Blue, it is actually a very hard colour to match. There's nothing in RAL or BS381c that comes close, while FS595 gives you 35231 but it's darker and greyer than AB:

Even a Pantone deck only gave approximate matches, and they were from the Violet end of the scale. To my eye at least, AB has always had a violet caste to it so that's not too surprising:

Humbrol isn't the only company who have struggled with Azure Blue. Xtracolor and Xtracrylic are actually different shades, and neither is a precise match:

I'll track down some other attempts at AB and see how they compare, both with each other and with the sample chip.

John

I am going to chip here with a bit of history. Bob Jones of IPMS founder fame (circa 1965) was greatly relied on by Humbrol when they were first formulating their colours. Bob used the BS 381:C 1964 book as the reference and Humbrol in turn used that as their reference. This is probably where the first errors occured with as Bob did not have access to the MAP range held at Hendon and the aircraft colours in the BS are different in hue values from the earler MAP colours. Nick will undoubtably be able to measure these. Bob made exactly the same errors for British army colours and we are still living with the consequences.

[Mike G]

I am going to chip here with a bit of history. Bob Jones of IPMS founder fame (circa 1965) was greatly relied on by Humbrol when they were first formulating their colours. Bob used the BS 381:C 1964 book as the reference and Humbrol in turn used that as their reference. This is probably where the first errors occured with as Bob did not have access to the MAP range held at Hendon and the aircraft colours in the BS are different in hue values from the earler MAP colours. Nick will undoubtably be able to measure these. Bob made exactly the same errors for British army colours and we are still living with the consequences.

I made a match to a printed chip in the Monogram guide to US colours which included the ANA equivalent. Not ideal I know but it looks reasonable. It was 3 parts Humbrol 25 to 4 parts Humbrol 33.

[Nick Millman]

I am going to chip here with a bit of history. Bob Jones of IPMS founder fame (circa 1965) was greatly relied on by Humbrol when they were first formulating their colours. Bob used the BS 381:C 1964 book as the reference and Humbrol in turn used that as their reference. This is probably where the first errors occured with as Bob did not have access to the MAP range held at Hendon and the aircraft colours in the BS are different in hue values from the earler MAP colours. Nick will undoubtably be able to measure these. Bob made exactly the same errors for British army colours and we are still living with the consequences.

Hi Mike S

Thanks for that - interesting! I measured MAP Azure Blue as 4.1 PB 6.2/6.0 whereas BS381C # 104 Azure Blue is approx 4.7 PB 3.1/6.1 (and is indeed more like the Humbrol paint colour). The DE2000 difference calculation between the two is a fairly humongous 28.4 where 2.0 or less is equivalent to a close match! (White vs Black is 100 which puts 28.4 to 2.0 in context).

Hopefully, Mike G, you meant to type Humbrol 34 for your mix? Humbrol 33 is matt black!

Nick

[Mike G]

Hi Mike S

Thanks for that - interesting! I measured MAP Azure Blue as 4.1 PB 6.2/6.0 whereas BS381C # 104 Azure Blue is approx 4.7 PB 3.1/6.1 (and is indeed more like the Humbrol paint colour). The DE2000 difference calculation between the two is a fairly humongous 28.4 where 2.0 or less is equivalent to a close match! (White vs Black is 100 which puts 28.4 to 2.0 in context).

Hopefully, Mike G, you meant to type Humbrol 34 for your mix? Humbrol 33 is matt black!

Nick

Errrr....yes, Nick Humbrol 34!! Otherwise you would end up with something like Night!!

[stevehnz]

Finally got around to trying some of the mixes as discussed in this thread & in the Humbrol Colour system chart HERE. Not comprehensive, still some more I want to do but this was nearly enough to confuse me.

The right panel has at the top #1, Aeromaster 9116 Azure Blue which lacking any of the other paint chips & standards swatches others have I've used as a reference. #2 on that panel is the mix mentioned above by Mike G. #s 3 & 4 are the Colour system proprtions (nearly) without the black, which #s 5 & 6 have. #5 looks to have got too much black perhaps, I find it hard to measure such small proprtions. It was then I remembered some advice on the Stormo site from Mike Starmer about adjusting for "scale" colour ('nuther can of worms?) in which he said for 1/72 to add 1part of light grey to 6 parts of colour or same of white to greys. In the right panel I have done this with #s 2 & 4. After that I decided that the 10:2 mix of Hu34:Hu25 is pretty much what I want in an Azure blue, the Hu25 seems to impart a slightly violet tint to ithe mix. Sorry if the photo doesn't do it justice.

Steve

[Prop Duster]

...

After that I decided that the 10:2 mix of Hu34:Hu25 is pretty much what I want in an Azure blue, the Hu25 seems to impart a slightly violet tint to ithe mix. Sorry if the photo doesn't do it justice.

Steve

Photo justice or not, your perseverance and dedication, to strive toward a solution, is impressive, as were the other contributers inputs and analysis . I thought I wouldn't give a "(?) brass farthing" when I started this thread.

Now, I find that I have learned some things re: color.

So, I'll have to be a bit more judicious in my color choices and not so dependent on the paint manufactures and /or model company's choices.

---darn it, now it's more complex poor little me, sigh

Really all, Thanks good job!

[stevehnz]

I thought to bring this thread back to Johns original premise, that Humbrol had inadvertently matched the wrong standard to arrive at its Authentic Azure Blue. Unfortunately, I don't think they did. Having found my old Vindicator kit which I know is painted with HB13 undersides (heavens knows why the Rareplanes instructions picked AB because everything I've read since indicates its totally wrong) & lined up a couple of mixes I've done along with Aeromaster 9116 & a patch of current Hu157 I reckon its fair to say that at one stage Humbrol DID make an HB13 which was a realistic option as an Azure Blue as seen below. Bear in mind this HB13 is the best part of 30-35 years old but has been in the dark for all but a few years of that time until recently.

Its obviously not too far from the Aeromaster 9116 & a heap away from current Humbrol 157. I feel I'm getting closer to a decent mix, I'm convinced Hu25 is the way to go for Blue, maybe with a touch of purple like Tamiya give as an Azure mix in their Spitfire kits (without saying what it is). I think though that their using XF18, which is not a lot different to Hu157 is too much of a grey/blue & lacks the violet edge that Azure Blue seems to have. Not having access to the RAF museum paint chips that John has, I'd like to see someone with the chips, the paint & the time try some mixes like I have. Maybe we can persuade Humbrol to change their mix & in any case, it would be handy for those who have limited access to paint ranges such as we find in NZ. Who knows, we could even find something to satisfy the science in Nicks methods rather than the TLAR that many of us go for.

Steve.

[John]

I thought to bring this thread back to Johns original premise, that Humbrol had inadvertently matched the wrong standard to arrive at its Authentic Azure Blue. Unfortunately, I don't think they did. Having found my old Vindicator kit which I know is painted with HB13 undersides (heavens knows why the Rareplanes instructions picked AB because everything I've read since indicates its totally wrong) & lined up a couple of mixes I've done along with Aeromaster 9116 & a patch of current Hu157 I reckon its fair to say that at one stage Humbrol DID make an HB13 which was a realistic option as an Azure Blue as seen below. Bear in mind this HB13 is the best part of 30-35 years old but has been in the dark for all but a few years of that time until recently.

Its obviously not too far from the Aeromaster 9116 & a heap away from current Humbrol 157. I feel I'm getting closer to a decent mix, I'm convinced Hu25 is the way to go for Blue, maybe with a touch of purple like Tamiya give as an Azure mix in their Spitfire kits (without saying what it is). I think though that their using XF18, which is not a lot different to Hu157 is too much of a grey/blue & lacks the violet edge that Azure Blue seems to have. Not having access to the RAF museum paint chips that John has, I'd like to see someone with the chips, the paint & the time try some mixes like I have. Maybe we can persuade Humbrol to change their mix & in any case, it would be handy for those who have limited access to paint ranges such as we find in NZ. Who knows, we could even find something to satisfy the science in Nicks methods rather than the TLAR that many of us go for.

Steve.

That's an extremely interesting photo Steve, and does perhaps support Graham's suggestion that the colour drifted over the years. As you say, though, any reasonable depiction of AB needs that slight violet caste that is so characteristic of the full size colour and which is missing from all the paints I've tried so far.

I wrote to Dale Luckhurst at Hornby a few weeks ago, pointing out the problem with the current 157 and asking if they could re-examine it as they did with 225 Middle Stone. He was interested and has passed my email on to the relevant people in the company.

Fingers crossed!

John

[stevehnz]

That's an extremely interesting photo Steve, and does perhaps support Graham's suggestion that the colour drifted over the years. As you say, though, any reasonable depiction of AB needs that slight violet caste that is so characteristic of the full size colour and which is missing from all the paints I've tried so far.

I found THIS to help verify that at one stage HB13 was as good as any for Azure Blue & looking at the finish, on the whole, authentic colours did give excellent results. Its worth it to pay a visit to the Spitfire builds HERE, scroll down to Spitfire, theres 5 pages of them. In wandering thru them it looks to me as the the Polyscale & Lifecolour Azure Blues come close to what we are looking for. Got either of them John?

I wrote to Dale Luckhurst at Hornby a few weeks ago, pointing out the problem with the current 157 and asking if they could re-examine it as they did with 225 Middle Stone. He was interested and has passed my email on to the relevant people in the company.

Fingers crossed!

John

That last is positive news & I hope they can do something with it. Hu227 Azure Blue sounds about right to me. Hopefully you also passed on a link to this thread so they can see what the nature of the problem is. I would then encourage them to simply let some of their superceded colours disappear.

Steve.