Interesting. One person mentioned that it was a normal routine in the film industry and that app is almost just as accurate.
So, while not exact, it can help a lot.
PowerBook grey filament? Which RAL?
- Thread starter mmu_man
- Start date
Interesting. One person mentioned that it was a normal routine in the film industry and that app is almost just as accurate.
So, while not exact, it can help a lot.
If anyone here knows someone who works for a place that does custom paint color matching (even Walmart, but honestly, their system isn't great) they should have a spectrophotometer you can use to get an idea of the color. Most match to a proprietary system (although some of the better ones match to Pantone), but they also almost always match to a common public domain system. The one at Walmart, if I remember correctly, maps to CIELAB as well as its own system.
From having worked with spectrophotometers in the lab, the most important aspect to keep in mind is to always check the Delta E of your measurement. Ideally you want your Delta E ≦ 2. Many people will tell you 3 is acceptable, but in all honesty, that can lead to quantifiable errors. If you stick to Delta E ≦ 2 you should be in excellent shape.
Also, many people will tell you that you only need to calibrate the spectrophotometer when it says its time to calibrate. That is only true if you honestly don't care about the accuracy of your measurements. Our major rule was calibration every 24 hours. You don't want to do it more often than that since you start to introduce intraday inter-calibration error because the spectrophotometer isn't meant to be constantly calibrated.
Lastly, many people will say you can use a sample as small as a dime for a match. That may be true with a system that is very high quality and is very well maintained. Generally, the average system couldn't provide a Delta E ≦ 2 with a sample smaller than a quarter.
From having worked with spectrophotometers in the lab, the most important aspect to keep in mind is to always check the Delta E of your measurement. Ideally you want your Delta E ≦ 2. Many people will tell you 3 is acceptable, but in all honesty, that can lead to quantifiable errors. If you stick to Delta E ≦ 2 you should be in excellent shape.
Also, many people will tell you that you only need to calibrate the spectrophotometer when it says its time to calibrate. That is only true if you honestly don't care about the accuracy of your measurements. Our major rule was calibration every 24 hours. You don't want to do it more often than that since you start to introduce intraday inter-calibration error because the spectrophotometer isn't meant to be constantly calibrated.
Lastly, many people will say you can use a sample as small as a dime for a match. That may be true with a system that is very high quality and is very well maintained. Generally, the average system couldn't provide a Delta E ≦ 2 with a sample smaller than a quarter.
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So, I got my RAL K7 palette… and spend like 3 hours trying to match the PowerBook 520c colors… No exact correspondence sadly.
I took photos using two distinct lamps including a full-spectrum one, I'll post some later. Here are the candidates I currently have:
For the light color:
- RAL 7012 / Basalt Grey (darker) (ColorFabb) - closest Pantone: P 176-12 U
- RAL 7037 / Dusty Grey (lighter) (ColorFabb) - closest Pantone: 424
- RAL 7005 / Mouse Grey (not exact tone)
For the dark color (screen hinges, ports door…):
- RAL 7043 / Traffic Grey B
- RAL 7022 / Umbra Grey
- RAL 7010 / Tarpaulin Grey
- RAL 6015 / Black Olive was suggested already here, not that close though.
I'll have to take another look. I'm more interested in the light one for now. I also checked Extrudr for possible filaments, but it seems although the advertise RAL colors, they just classify their filaments by the closest RAL without actually verifying the accuracy, which would explain the 7044 discrepancy that was found. Also they don't seem to have many of the candidates sadly, but I'd need a matching TPU for the PowerBook power connector remake…
I took photos using two distinct lamps including a full-spectrum one, I'll post some later. Here are the candidates I currently have:
For the light color:
- RAL 7012 / Basalt Grey (darker) (ColorFabb) - closest Pantone: P 176-12 U
- RAL 7037 / Dusty Grey (lighter) (ColorFabb) - closest Pantone: 424
- RAL 7005 / Mouse Grey (not exact tone)
For the dark color (screen hinges, ports door…):
- RAL 7043 / Traffic Grey B
- RAL 7022 / Umbra Grey
- RAL 7010 / Tarpaulin Grey
- RAL 6015 / Black Olive was suggested already here, not that close though.
I'll have to take another look. I'm more interested in the light one for now. I also checked Extrudr for possible filaments, but it seems although the advertise RAL colors, they just classify their filaments by the closest RAL without actually verifying the accuracy, which would explain the 7044 discrepancy that was found. Also they don't seem to have many of the candidates sadly, but I'd need a matching TPU for the PowerBook power connector remake…
