Acetone test results megathread

[verticity]

Here's the link to @Deleted User's discussion of the paper where Lebot validated the acetone test (includes the paper):
http://kavaforums.com/forum/threads/acetone-test-now-validated-by-dr-lebot.7131/
Quote from abstract:

"The significant (+0.757**) correlation between the total FK content and the extracts absorbance at 400 nm indicates that a simple colorimeter can be used to detect poor-quality raw material."​

 

[Sam Handwich]

Another Acetone test, on the left is KWK Borogu (known noble) then Lami Kava, then Kava Time. On the far right is KBR Tudei. As always it's tough to get accurate photos but I'm not worried about either of these. Both Kava Time and Lami look good and are actually a little lighter to the eye.

 

[Deleted User01]

The test results with the windows as background seems to do them more justice. Interesting post. the one against the white background was less flattering to at least 1 on them.

 

[Sam Handwich]

The test results with the windows as background seems to do them more justice. Interesting post. the one against the white background was less flattering to at least 1 on them.

Agreed, oddly enough the one that looks darker with the white background is actually the lightest one of the 4 to the naked eye. Just goes to show that photos of the acetone test are pretty worthless unless the difference is huge.

 

[verticity]

Another Acetone test, on the left is KWK Borogu (known noble) then Lami Kava, then Kava Time. On the far right is KBR Tudei. As always it's tough to get accurate photos but I'm not worried about either of these. Both Kava Time and Lami look good and are actually a little lighter to the eye. View attachment 6959 View attachment 6960

Props for using natural sunlight in the photographs. The reason that is good is that the absorption peak is around 400 nanometers, which is well covered by natural sunlight, but not so much by incandescent or fluorescent lights. This picture compares the spectral distribution of daylight, incandescent tungsten lights, and fluorescent lights:

Notice that daylight is the most uniform, and also has the greatest intensity at 400 nm, which is very important for accurately seeing the color of acetone tests. The incandescent light is much less intense at 400 nm relative to the rest of the spectrum; in fact the peak of an incandescent bulb is in the infrared (this is because the color temperature of a hot tungsten filament is about 2400 K; it is much cooler that the Sun, which has a peak in the blue-green, and a color temperature of 6500 K). Also, you can see from the picture above that fluorescent lighting has distinct peaks, with very little intensity around 400 nm, so fluorescent lighting would be complete unsuitable for looking at or photographing acetone tests.
An electronic flash lamp has a color temperature of 5500-6000 K, so that might help, but it is best to photograph acetone tests outdoors on a sunny day (or using sunlight through a window like you did) if possible.
As far as background, I think the white background is better, because otherwise the background colors are not uniform, which can distort the appearance of a photograph.

 

[Sam Handwich]

Wow! That is really awesome, thank you for putting this together.

 

[verticity]

Actually that picture looks fairly accurate. Here it is again with the white balance corrected to 6500K (based on the paper behind the bottles), and a section of each bottle moved up to make comparison easier. Depending on the calibration of your monitor, you should see a definite orange tint in sample 4.
View attachment 6971

Here's a pic of calibrated filters, the distinction between the noble/two day sections - yellow vs orange - is what makes the difference.
View attachment 6972

Will the cards be available for sale? A number of people have been asking.

 

[verticity]

Actually that picture looks fairly accurate. Here it is again with the white balance corrected to 6500K (based on the paper behind the bottles), and a section of each bottle moved up to make comparison easier. Depending on the calibration of your monitor, you should see a definite orange tint in sample 4.
View attachment 6971

Here's a pic of calibrated filters, the distinction between the noble/two day sections - yellow vs orange - is what makes the difference.
View attachment 6972

Also, am I correct in assuming that there are no "adulterated" filters in that? That is all the top ones are 100% tudei with varying saturations, and likewise the bottom ones are 100% noble with varying saturations? i.e. the darker yellow filters on the bottom are not "more noble" than the lighter yellow ones? I think there has been some confusion among some folks between "darkness" vs "orangeness"...

 

[verticity]

@Deleted User since you're here, could you please provide the details about how you make your really nice a-test photographs? What kind of lighting do you use?

 

[Kojo Douglas]

@Deleted User do you think, according to the results, that Lami Kava looks like Two Day # 6 on your card?

 

[verticity]

...None of the filters denote true "adulterated", though #4 is basically what you could expect from an adulterated sample....

Sorry, I don't quite understand. Are you saying #4 represents a hue that would correspond to a certain percent adulteration, or not?

 

[verticity]

...When I take pictures of tests, I use a pure white background and 6500K fluorescent lighting, about 3/4 of the lighting on the background. ...

Hmm, using fluorescent lighting might not be ideal, because fluorescent lighting has discrete lines, it is not continuous black-body radiation (like the Sun). The fact that an effective color temperature can be assigned to it does not mean it is equivalent to D65. But your pictures do look good....
To really simulate daylight well you would need a plasma grow light.

 

[Kava Time]

Another Acetone test, on the left is KWK Borogu (known noble) then Lami Kava, then Kava Time. On the far right is KBR Tudei. As always it's tough to get accurate photos but I'm not worried about either of these. Both Kava Time and Lami look good and are actually a little lighter to the eye. View attachment 6959 View attachment 6960

Is it just me or does lami kava results by the window look murky? Which batch did you use for this test? Pre cyclone or post?
Does anyone know apart from the scientific testing of kava, how tudei can visibly be distinguished from noble when the roots are in dried form?

 

[kasa_balavu]

Does anyone know apart from the scientific testing of kava, how tudei can visibly be distinguished from noble when the roots are in dried form?

There is no way to tell dried noble root from dried tudei root. It's not like false kava, which have roots that look different and smell different (very peppery).

 

[Sam Handwich]

Is it just me or does lami kava results by the window look murky? Which batch did you use for this test? Pre cyclone or post?
Does anyone know apart from the scientific testing of kava, how tudei can visibly be distinguished from noble when the roots are in dried form?

The Lami was from the trial offering from a few weeks ago. It was the last one that I mixed up and had only settled overnight, perhaps that's why it looks a bit cloudy.

 

[verticity]

Filters #1, #2, and #3 are different saturations (intensities) of the same hue (dominant wavelength ~575.9nm), which is typical of all verified noble samples. Filters #4, #5, #6, and #7 use the same principle, and are indicative of the dominant wavelength of verified two day samples (~582.1nm). ... since the orange hue tends to overpower the yellow, a 25% adulterated noble could easily match filter #4, i.e. the presence of this hue is a basically positive indicator of two day content. The exact degree of adulteration cannot be determined by this method, ...

OK, I see what you are saying.
The filter card could be useful as a rough screening tool, but it is not as accurate as analyzing the full spectrum.. Nonetheless, it would be very useful, if it came with a very clear set of instructions about what it can and can't be used for.

 

[verticity]

I guess it would be possible to make a card showing "adulterated" dominant wavelengths in addition to pure ones. I'm picturing like a grid with 3 or 4 columns and 5 rows. The top row would be various saturation levels of the "tudei" hue. The bottom row would be the same for the "noble" hue. The rows in between would have filters representing blended (75%, 50%, and 25%) hues, also with a range of saturations. It might be confusing to use at first, but would be a good reminder for people to show they should be looking for hue, not saturation, and would be good "eye training" to tell the difference.