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Author Topic: 1927 1937 undersurfaces blue paint (inportant new infos)  (Read 12702 times)
righidan
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« Reply #30 on: April 19, 2015, 09:25:53 PM »

Dear friends,
   sorry to answer so late, but among many other things, I have changed PC, operating system, browser and screen, and I have met many, many more gremlins than I would have liked!
   Dear Massimo, I think that the color could be related, but unluckily the gondola is not near enough to be measured with my colorimeter and I think we should wait for a restoration to be sure.
   Dear Xan, no, I was not able to see any other blue, and being very old and so not so much optimistic, I still remember that the imperial War Museum painted his FW190 like this:



Since then the times have changed a lot?
Best regards
Daniele Righi
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Daniele
Massimo Tessitori
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« Reply #31 on: April 19, 2015, 10:16:50 PM »

Hi Daniele,
new pc, new gremlins... seems an hard time!
In absence of other data, I'm prone to identify a possible prewar blue with the darker shade on the piece of I-16. Old photos seem to show a relatively dark shade, so it could have been not too different from AMT-7.
Regards
Massimo
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righidan
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« Reply #32 on: April 22, 2015, 01:01:40 AM »

Hi Massimo,
   I think that you are right, the two colors are probably similar, and I hope to be able to prove it.
   So let us start a rather long digression...
   Even if I believe that every modeller can paint his model with whatever color he likes, as long as he has fun, I have fun trying to analyse colors in a complex way.
   So I decided to get a colorimeter, that is a rather pricey instrument used by the industry to assure color consistency.
   To analyze some Akan colors I have used a ?Color Striker? produced by Mathai, which can measure color without touching the object, as it is also used to asses the color of female hair to produce wigs.
   I will not dwell in the enormously complicated science of color, but I will enclose the briefest and clearest (for me) description of the CIE (International Commission on Illumination) L*a*b* coordinates, measured by my instrument, that I have found at the address: http://www.briarpress.org/15154 .
   It refers to how obtain Pantone colors but that is valid for other colors too.
?Along with matching visually, we use a spectrophotometer. This device reads and gives you Lab values. You can use the Pantone book as a reference and use the color that you are mixing (printed version) and scan that vs. the reference. This gives you the difference between the two colors.
For instance, if you have Lab values where your L (lightness) is high, your a value is high, and your b value is low, then you would want to look on the Lab image posted.

This will let you know what color to add, based on the Lab values you are getting. Like in the example I gave, if L is high then add black, if a is high then add green, and if b is low then add yellow. Hope this helps!?
   So using a colorimeter will give you two advantages: the first is that the color is translated in numbers, and these numbers are forever and can be used for any comparison, the second is that if two colors are different, it will tell you how to correct them to make them identical.
   Simplifying a lot, and stretching the numbers a little bit, we can say that: up to a Delta (difference) of 1, the two colors are identical, up to a Delta of two, they are very close, up to three, they are close, up to four, they are similar, up to five they are somehow similar, over five they are clearly different for most humans.
   The two colors that I have measured are Akan 83042 and 73042, that are the enamel version and the acrylic version of A II G Blue.

   As you can see from the first image, there is a small difference between the two, and essentially the acrylic version is lighter, and lacks a little bit of red and yellow.
   I consider the enamel more accurate, so from now on I will take the measure of 83042 as standard, and its value is: CIE Lab: 59.95, -11.65, -5.32, or s RGB 115,151,152.
   It was asked before in this tread how A II G compares with Luftwaffe RLM colors, and here it is, measuring the German colors from the samples in the latest book of Mr. Ullman ?Luftwaffe Colours 1935 - 1945?

As you can see, RLM 76 is completely off, with a difference of almost 10
Rlm 65 is only somehow similar, with a difference (Delta) of 4.37.

The best match is.... RLM 78! with a Delta of 2,46 it appears to be close, and it could be used ?as it is? or adding a little of yellow, and just a dash of green and white.

   Of course this does not mean that Russians have used German tropical colors, or that Germans have copied Russian colors, but simply that the amount of shades and pigments to paint military planes in the last century was limited, so many colors are similar in different nations.
   Another question is if there is a standard color that is similar to A II G as interpreted by Mr. Akan.
   Unluckily there are no similar shades in the FS 595, according to the advanced tool in the site www.e-paint.co.uk, but there are similar shades in the RAL Design color charts, with RAL 210 60 15 having a Delta of only 1,76

The problem is that buying a RAL Design color chart, that contains 1625 colors, is quite expensive, at 112,50 pounds each, and even buying a single color costs almost 10 pounds
   Having made the study of Akan A II G complicated enough up to now, I will paint other paper labels with the Akan paints 8302 and 7302 for AMT 7 Blue, and post the results, assuming that there is somebody interested ?
   Best regards
Daniele

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Daniele
Massimo Tessitori
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« Reply #33 on: April 22, 2015, 08:20:03 AM »

Hi Daniele,
yes, it's interesting.
In consideration of the fact that two chips of the same producer are scarcely consistent, an approximation with other paints, easier to find, is very interesting. If you find chips of commercial paintings too, this will make things even more useful.
Regards
Massimo
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66misos
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Absence of evidence is not evidence of absence.


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« Reply #34 on: April 22, 2015, 01:47:09 PM »

Hi Daniele,
it is very interesting. Surely post, please, results about AMT-7.
Do you plan to make similiar measurements also with greys AMT-11 and AMT-12 and green AMT-4? It would be also very helpfull.
Thank you for your effort.
Regards,
   66misos
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righidan
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Posts: 39


« Reply #35 on: April 23, 2015, 12:49:45 AM »

Dera friends,
   thank you for your encouragement.
   Yes, I have got several other WW2 colors from Akan, and I plan to measure them.
   And then of course it would be very interesting to analize colors more readly available in the west.
   Measurng colors is not too much time consuming, but, unluckily, i have (too) many other things to do, and so I work slowly, please be confident, but it will take some time.
   Best regards
Daniele
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Daniele
Massimo Tessitori
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« Reply #36 on: April 23, 2015, 12:47:50 PM »

Hi Daniele,
I see, time is tyrannic. We'll wait for your results with interest.
The most time consuming thing will be to find the chips of other paints to compare. I think that comparisons are reliable only if made with the same device.
Regards
Massimo
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Spitfire
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Posts: 143


« Reply #37 on: April 23, 2015, 08:10:20 PM »

This is very useful, information I have been trying to match AKAN enamels to the Humbrol, Xtracolor, and Testors Model Master range by eye, it would be nice to see some slightly more scientific information.

Cheers

Dennis
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