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UltravioletPhotography

Photo Ninja: Profiling for UV Photos


Andrea B.

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Visible Profile Example for the Pentax K5 + W.Acall Kyoei 35mm f/3.5 lens + Baader UVIR-Cut Filter

A Color Checker Passport was photographed with for use in Photo Ninja.

The white balance was read on the center left Labsphere reflective standard using the PN Color Correction dropper.

The profile was then created with Photo Ninja's profiling grid and stored as K5_Kyoei.

 

Photo Ninja requests a slightly blurred photo of the CC Passport.

k5_kyoei35_ccp_visSun_092014mt_122440pn.jpg

 

 

UV Profile Example for the Pentax K5 + W.Acall Kyoei 35mm f/3.5 lens + Baader UV-Pass Filter

The Labsphere white reflective standard was photographed.

The white balance was read on the center left standard using the PN Color Correction dropper.

 

There are 4 possible choices for Light Source in the drop down menu in the Color Correction Tool.

  • Match Color Temp
  • No Profile
  • Daylight/Flash
  • K5_Kyoei

Here is what the UV shot looks like for each choice.

 

Match Color Temp

The false colours are purple/blue.

k5_kyoei35_std_uvBaadSun_092014mt_122516wbMatchColorTemp.jpg

 

No Profile

The false colours are cyan/blue.

k5_kyoei35_std_uvBaadSun_092014mt_122516wbNoProfile.jpg

 

Daylight/Flash

The false colours are purple/blue.

k5_kyoei35_std_uvBaadSun_092014mt_122516wbDaylightFlash.jpg

 

K5_Kyoei

The false colours are blue.

k5_kyoei35_std_uvBaadSun_092014mt_122516pn.jpg

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UV Profile Example for the Pentax K5 + W.Acall Kyoei 35mm f/3.5 lens + Baader UV-Pass Filter

The Labsphere white reflective standard was photographed.

The white balance was read on the center left standard using the PN Color Correction dropper.

 

There are 4 possible choices for Light Source in the drop down menu in the Color Correction Tool.

  • Match Color Temp
  • No Profile
  • Daylight/Flash
  • K5_Kyoei

Here is what the UV shot looks like for each choice.

 

Match Color Temp

The false colours are purple/blue.

No Profile

The false colours are cyan/blue.

Daylight/Flash

The false colours are purple/blue.

K5_Kyoei

The false colours are blue. --Image strings not quoted

 

You really got my attention with this posting.

So, which light source choice is correct?

Isn't your K5_Kyoei a visible profile for the Baader UVIR-Cut Filter?

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So, which light source choice is correct?

 

John, I haven't the slightest idea if there is a "correct" choice. We are dealing with false colours here.

 

My personal choice is to select the last - the camera/lens profile - to apply to the false colours in the UV foto. My thinking is that if the colours are false, they might as well be bent to same camera/lens profile that is applied to the Visible fotos. That is not a scientific decision, of course. :D

 

I suppose a good case could be made for choosing the Match Color Temp setting. Although I do not know exactly how the colours are determined for this selection. Presumably cooler temps are bluer and warmer temps are redder. OTOH the colour temp we arrive at after white balancing a photograph is not "real" in any sense, so you could equally make a good case against the Match Color Temp choice. Note that it is mostly an artifact of a particular converter what colour temperature you will get after white balancing a UV foto. Some converters do not go as low as 2000K. Other converters can go below 2000K.

 

I think one can safely ignore the No Profile choice. And the Daylight/Flash choice is no doubt the same as you would get from Match Color Temp if your foto's colour temp was a typical 6500K sunny day.

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Fascinating, It would never have occurred to me to apply a Vis custom profile to a UV filter. In face since all the choices are actually for Vis I have tried to use Match Color Temp and more recently No Profile. The Art Set photo I recently posted was Light Source=No Profile & WB Mode=Manual

 

Since we actually do not have a UV-profile or any way to establish one I reasoned No Profile might actually be the "correct" option. Apparently you make an opposite conclusion in ignoring No Profile. I am confused because, to my eye at least, the No Profile image in your 20Sep14 comparison seems closer to your preferred K5_Kyoei than the other two. I guess it is because I have tried to learn how to avoid the purples so much that a cyan cast seems better! :D

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We need to look into it some more. And think about it.

 

Recall that Bjørn and I decided long ago that our "standard" for botanical presentations in UV would be the blue/yellow/gray false colour scheme.

 

We derived this false colour scheme during the Desert Wildflower Safari #1 of 2012 by performing a white balance on Labsphere white standards in the converters Bibble and Capture NX2 from photographs we made in Ajo, Arizona. We also played with adjusting RGB curves to support this look.

[ADDED: Other UV photographers have derived such color schemes in other ways - usually making use of white balance in some manner.]

 

Later when we began to use Photo Ninja it turned out that the combination of UV white balance and Visible Camera Profile gave this look too.

 

I have argued that the camera profile (or camera/lens profile) made from Color Checker Passport should be used for all work from a broadband camera - and not just restricted to visible work - because once the internal filters are removed, then both original visible colours and derived UV/IR false colours are altered "by the same amount" or "in the same way".

In Visible shots from a converted camera, simply performing white balance does not quite restore colours to the same colours that would have been produced by the unconverted version of the camera. You also have to add a converted camera profile to finish pulling the colours back to the proper originals. Therefore the same goes for UV shots.

Does that make any sense?

 

Anyway, that's the history.

 

What would be interesting to illustrate is the effect of the different Light Source choices on the false yellow.

I'll go dig out a Sunflower and test that now.

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Please let me know of any errors, typos, goofs or mis-interpretations.

I'd like to get this profiling thing done right and better understood.

 

Test: Appy different Photo Ninja Light Source profiles to Visible white balanced photo.

Subject: Color Checker Passport

Equipment: K5-broadband + Asahi 85mm f/4.5 Ultra-Achromatic-Takumar

Filter: Baader UV/IR-Block Filter

Exposure: f/8 for 1/500" at ISO-160

Light: Sunlight/14:44 EDT/UTC-4/120'/40.4°N

Converter: Photo Ninja

 

Reminder: Photo Ninja requests a slightly blurred photo for profiling.

Also, converting Tiffs to Jpegs for web display using the sRGB colour space may cause the CC Passport photo to vary from the actual CC Passport.

 

K5 JPEG: White balance set in-camera against a Labsphere reflective standard.

The K5 Natural colour setting was used.

Observe that for a converted camera, setting an in-camera white balance may not completely restore the original colours. I have had a few examples where it comes close, but it cannot be depended upon for a documentary photograph, imho.

1_PNTX0002inCamWB.jpg

 

Photo Ninja PEF Conversion: White balance set with Color Correction dropper.

Light Source: No Profile

Color Enhancement: Plain

Clearly this is not a wise choice for the Light Source setting.

And so we can observe that for a converted camera, setting the white balance in the converter without an application of a color profile may not completely restore the original colours.

2_PNTX0002pnWBNoProfile.jpg

 

Now let's add some color profiling to the photo. We have 3 choices in Photo Ninja: Match Color Temp, Daylight/Flash, K5_UAT Custom Light (made with CC Passport). You will see that the following 3 profiled photos have better colours (more correct) than the Jpeg version and the unprofiled version.

 

Photo Ninja PEF Conversion: White balance set with Color Correction dropper.

Light Source: Match Color Temp

Color Enhancement: Plain

Note that the photo looks much the same as the next Daylight/Flash version -

not surprising because the photo was made in early afternoon strong sunlight.

4_PNTX0002pnWBMatchColTemp4250-57.jpg

 

Photo Ninja PEF Conversion: White balance set with Color Correction dropper.

Light Source: Daylight/Flash

Color Enhancement: Plain

Note that the photo looks much the same as the preceding Match Color Temp version.

Not surprising because the photo was made in early afternoon strong sunlight.

3_PNTX0002pnWBDayFlash.jpg

 

Photo Ninja PEF Conversion

Light Source: K5_UAT Custom Light Profile

Color Enhancement: Plain

There is not a huge change between this properly profiled photo and the preceding two, but there are differences which could be important in a documentary photograph. The differences could occur on other colour patches than are seen here depending on lens and illumination. See next composite photo for a better illustration of differences.

5_PNTX0002pnK5UATProfile.jpg

 

Comparison of Match Color Temp conversion with K5_UAT Custom Light Profile conversion.

Upper Left of each color patch from Match Color Temp conversion.

Lower Right of each color patch from K5_UAT Custom Light conversion.

(Composite made in PS Elements 11.)

5_PNTX0002_Compare_ULMatch_LRProfile.jpg

 

As always, all comments, suggestions and questions welcomed.

 

*********************************************************************************

 

Test: Appy different Photo Ninja Light Source profiles to UV white balanced photo.

Subject: Silphium perfoliatum

Equipment: D600-broadband + Nikon 80mm f/5.6 EL-Nikkor

Filter: Baader UV-Pass Filter

Exposure: f/11 for 1/125" at ISO-800

Light: Sunlight/15:05 EDT/UTC-4/120'/40.4°N

Converter: Photo Ninja

 

Photo Ninja NEF Conversion: White balance set with Color Correction dropper.

Light Source: No Profile

The blue bits look mostly ok but are tending to the cyan side a bit. The yellow has a pinkish cast.

silphiumPerfoliatumUVBaadSB14_082514deepCutMtNJ_26247origpnNoProfile.jpg

 

Photo Ninja NEF Conversion: White balance set with Color Correction dropper.

Light Source: Match Color Temp

The blue bits have a purplish cast. The yellow looks ok.

silphiumPerfoliatumUVBaadSB14_082514deepCutMtNJ_26247origpnMatchColorTemp.jpg

 

Photo Ninja NEF Conversion: White balance set with Color Correction dropper.

Light Source: Daylight/Flash

The blue bits have a purplish cast. The yellow looks ok.

silphiumPerfoliatumUVBaadSB14_082514deepCutMtNJ_26247origpnDaylightFlash.jpg

 

Photo Ninja NEF Conversion

Light Source: D600_VisSun_Profile

Both blue and yellow look good.

silphiumPerfoliatumUVBaadSB14_082514deepCutMtNJ_26247origpnProfiled.jpg

 

Silphium perfoliatum in Visible light

Just for the record.

f/11 for 1/1250" at ISO-800

silphiumPerfoliatumVisSun_082514deepCutMtNJ_26228origpn.jpg

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I disagree that using a visible light profile is relevant to the colour balance of a UV photograph. In fact, the software has no clue as to what spectral response the Bayer dyes have outside of the visible range. The 'no profile' option is the only logical one for UV photography.

 

At present we have no known colour patches in the UV except for the spectrally neutral Labsphere and similar. These provide UV 'white', UV 'grey', and approx. UV 'black'. under the given spectral distribution in the UV band as seen through a given lens. A single UV w/b target is simply not enough to make a reliable colour palette unless one assumes a flat spectral response which obviously hardly exists. So, we are presented with an unstable system with too many unknowns and too few actual data points. Hardly surprising one observes such diversity in actual rendition of a scene in UV. We can obtain general likeness in the UV rendition, as shown so many times with different lenses and cameras, but precise false-colour matching is hardly attainable at present. I doubt in fact this never is to happen unless all lenses and cameras are identical in their UV behaviour which it not going to happen anyway.

 

What we should do is looking at similarity patterns and refrain from reading UV false colours as signalling a measure of narrow-band prevalence within the UV band.

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Bjørn: In fact, the software has no clue as to what spectral response the Bayer dyes have outside of the visible range.

 

Andrea: This is certainly true. That's why we have called them False Colours from Day One.

 

Bjørn: The 'no profile' option is the only logical one for UV photography.

 

Andrea: I totally disagree because in Photo Ninja the "No Profile" option does NOT give

our standardized blue/yellow/grey colour scheme agreed upon in 2012.

The Photo Ninja No Profile option - AS ILLUSTRATED ABOVE - does NOT give a nice Yellow or a nice Blue.

PN No Profile gives a Yellow with too much red and a Blue with too much green. Total yuk !!

 

I am rather surprised that you would suggest using the No Profile option in Photo Ninja because

for aeons now, you yourself have been showing CC Passport photos in UV with BLUE patches

and not with the cyanish-blue patches that No Profile gives.

 

Also, you are forgetting that other converters apply various profiles without your knowing about it.

Photo Ninja is one of the rare converters that gives you an option to have "No Profile".

Any other converter I use is applying some kind of profiling to the colours.

 

Bjørn: ...refrain from reading UV false colours as signalling a measure of narrow-band prevalence within the UV band.

 

Andrea: I totally agree. I have been advocating and warning about this constantly.

However, reading too much into false colours does not have anything to do with our agreement to use a standardized blue/yellow/grey palette as we originally developed it in 2012.

 

[ADDED: There has been some misunderstanding about the preceding sentence. Our agreement was developed in 2012. We figured out how *we* wished to standardize the b/y/g palette by using *our* choice of certain converter/editors and standards. But we have never claimed we "invented" anything here. Some people have misread the preceding paragraph.]

 

Andrea: I am always open to abandoning our blue/yellow/grey palette and just letting the False Colours fly as they will.

Just let me know and I will rewrite the Guidelines.

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Well, changes of mind can occur you know :D. Although we're talking about less shifts in rendered colour than going say from ARGB to sRGB. The basic blue-yellow-grey palette remains.

 

Besides, 'no profile' is not any significant change in approach, on the contrary. The same underlying rationale applies and only the pre-defined (and largely non-valid for UV) bias is left out. We try to twist the camera response to fit the (few) available reference points as closely as possible. PhotoNinja has a good w/b capability, better than most converting software out there, but it is not perfect. I do wish PN had a curve tool to make the last-minute adjustments to the UV rendition.

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PN could definitely use a curve tool. But I've become adept at popping the output Tiff into some other editor for curve adjustments. It's all we can do for now.

***********

 

Let me show you our original test photo - which was actually from Death Valley. A good old Encelia. Remember those? Very abundant they were. Almost taking over parts of California IIRC.

 

Anyway, you profiled this Encelia photo in Bibble. Must have been Bibble 4?? And I practiced on it in both Bibble and NX later. This was before we shot the standards in Ajo, Arizona in that parking lot. I only had a small color patch card back then. This original profiling effort has the blues tending towards purple. (This happens a lot anyway.) I do not recall today whether or not this version was made in Bibble or in NX, but we had agreed it looked good and I subsequently named the file with the word "PROFILE" as a prefix.

 

27 Feb 2012, Death Valley, California

D300-broadband + UV-Planar + Baader-U

We were soooo pleased with how this looked. :D

PROFILE_6BaaderU_WB_Neutral0_QFExp+1Shadows+50_LevelsGWAuto_Sat_Tweaks.jpg

 

Now, let me show you the same photo converted in Capture NX2 and in Photo Ninja. You will kindly note that the first two of the following three conversions look pretty much like the original "PROFILE" photo above. They also look pretty much like each other. Then note that the last conversion looks terrible.

 

First, a Capture NX2 conversion.

To maintain uniformity of the histogram across the conversions I want to show you, I have deliberately not finished this photo. Further edits would be required to 'finish' the photo. I've kept edits in each case to simply choosing a neutral picture control and to the white balance effort.

  • Neutral[0] picture control chosen.
  • White balance applied to center standard.
  • Exposure raised +1.5.
  • No other edits except to resize and apply sRGB for web display.

For anyone not using NX2, when white balance is applied to a UV photo, NX2 causes a real wrench to the exposure. So that must be compensated for using NX2's exposure slider and sometimes using adjustments to the B/W point or Shadows slider.

uvBaaderSun_D300_IncanG6_022712mt_21545_nx2NeuWBExp1.5Res.jpg

 

 

Now, the first Photo Ninja conversion.

  • Plain color enhancement chosen with default 50% saturation.
  • White balance applied to center standard.
  • D300 visible profile applied as Light Source in white balance tool.
  • No other edits except to resize and apply sRGB for web display (which, btw, I also did in NX2 because I have a saved edit there for resizing tiffs).

uvBaaderSun_D300_IncanG6_022712mt_21545origpnWBPlain50PcntSatNoSharpRes_D300Profile.jpg

 

 

And finally, the second Photo Ninja conversion.

  • Plain color enhancement chosen with default 50% saturation.
  • White balance applied to center standard.
  • No Profile applied as Light Source in white balance tool.
  • No other edits except to resize and apply sRGB for web display (again done in NX2).

You can now see that the choice of No Profile is not a natural choice for a UV photograph. The colours, saturation and contrast have gone awry (which is a polite way of saying that the colours, saturation and contrast have gone to hëłł.

uvBaaderSun_D300_IncanG6_022712mt_21545origpnWBPlain50PcntSatNoSharp_NoProfileRes.jpg

 

To make this unprofiled UV photo a bit more like the others I will increase its saturation a bit. This will at least show you the bad colours a little better. The blue heads towards cyan. It is not a horrible blue, but it is not a nice UV blue either.

uvBaaderSun_D300_IncanG6_022712mt_21545pnWBPlain50PcntSatNoSharp_NoProfileSat75.jpg

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I have lots of examples I could flood the thread with to show 'no profile' gets you the better-looking UV colours. The sample in the last post is definitively underexposed, by the way.

 

Do remember when you apply a defined profile to the conversion and this data is obtained in visible light, you actually instruct the software to add a specific bias to each colour channel. We have absolutely no evidence the response in UV requires a similar pre-adjustment. So basically the profiling (or actually, calibration, as we tend to use a single reference for w/b has first to undo the imbalance brought about by using the visible-light profile (such as 'Daylight/flash') then to realign the channels so the reference comes out neutral as it should. We work with a data-deficient calibration system, and the sensitivity to outliers is obviously high as the colours attained can be very unstable and minute adjustments throw them off.

 

Then there is the Pandora's box of colour spaces, monitor profiling and calibration, and what to use on the 'net. I feel we spend time unwisely if rather insignificant changes in hues of false colours are deemed very important. It's rather like the old discussion of Fuji vs Kodak colour films. More important is that we get a similarity in overall UV false-colours that is pretty much consistent.

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Do remember when you apply a defined profile to the conversion and this data is obtained in visible light,

you actually instruct the software to add a specific bias to each colour channel.

True.

 

We have absolutely no evidence the response in UV requires a similar pre-adjustment.

True.

But we also have absolutely no evidence that the UV response does not require a pre-adjustment.

 

...profiling has first to undo the imbalance brought about by using the visible-light profile (such as 'Daylight/flash')

then to realign the channels so the reference comes out neutral as it should.

Profiling does not "undo" anything. Profiling takes whatever "raw" colours are recorded and translates them to profile colours.

But whatever, just semantics on this one.

 

Why I apply the camera colour profile to both Visible and UV photos:

  • We have altered the camera's original colour response by removing its internal filters.
  • A camera profile restores the original colour response (and in some cases may even better it).
  • The camera does not know what kind of light it is receiving.
  • The camera outputs colours from any light it receives.
  • Repeat, the camera blindly receives light and outputs colours in a Crank the Black Box's Handle manner.
  • If we restore the camera's original colour response with a profile,
    then the profile might as well be applied to all output colours regardless of the input wavelengths that created them.
  • In short, I advocate True False Colours as well as the generally accepted True True Colours.

*****************

*****************

 

Dear Readers:

 

Bjørn and I debate this topic from time to time. Sometimes we switch sides in these debates. When we first had this debate, Bjørn wanted to use Daylight/Flash and I wanted to use No Profile as a Photo Ninja Light Source. That was before we even figured out how to make CC Passport profiles in Photo Ninja. But now we have changed positions. :D We may change again in the future.

 

Please note that it does not matter even a tiny little iota whether or not one uses profiled false colours or unprofiled false colours !!!!! We only try to keep UV botanical photos in the blue/yellow/grey ballpark, but we are not fussy should the blues drift off-base towards purple or cyan and the yellows towards orange. (Although I kinda do not like pink casts in UV photos. That's just wrong.)

 

 

*****************

*****************

 

Way, way back up there in this elongated thread many days ago, I mentioned being wierded out by the fact that the mob of M42 lenses I tested seemed to be all over the map in their colour response. I am still weirded out by that. I keep thinking I did something wrong with my profiling and white balancing and all that stuff. Maybe we could get back to that. Because I surely do not know how we can keep to a blue/yellow/grey palette with those kind of lens responses shown above !! So the thing Bjørn and I were debating may be simply moot.

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"Profiling does not "undo" anything. Profiling takes whatever "raw" colours are recorded and translates them to profile colours."

 

If true, it shouldn't have mattered what spectral distribution was input as long as one does w/b against a spectrally neutral target. We already know this to be false. Change the assumed light source and PN responds by altering the output colours - even when doing the w/b properly. Switch back and forth after a w/b operation and see how the result differs. So there are behind-the-curtains adjustments going on.

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Alex, thanks !! An aperture series makes sense.

 

*****

 

Bjørn, we may be talking past each other on this one. "-)

I had thought that the Light Source was an integral part of a Profile.

So changing it implies a different Profile.

But if the Light Source is not an integral part of a Profile, then true.

 

It is called "Custom Light Profile" in Photo Ninja.

 

I'm worn out. :D

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Andrea & Bjørn,

 

Thank you both for giving so much effort into a question I raised. I have been riveted to this exchange and understand now this is a recurring question about an ongoing issue.

 

One point I might offer is that, in my spectral calibration work it is vastly better to have the wrong calibration rather than no calibration. I can always perform a spectral deconvolution and reconvolution to correct for that. Perhaps the use of any profile might, in an analogous way, be preferable to No Profile especially if it lends to more reproducible, truer, false colors.

 

Again, much appreciated!

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To the extent that we have been able to shed any light (should I say 'UV light' ?) on the matter, you are welcome John.

 

And here we were talking about only one converter - Photo Ninja.

Heaven knows what choices to make in all the other converters !!

 

BTW, I bumped the original thread about this: http://www.ultravioletphotography.com/content/index.php?/topic/333-photo-ninja-colour-correction-light-source-tab/

You should find it easily under this post.

I liked the original thread because it had an actual flower example.

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I like that you made this into it's own thread and refreshed the original, I was just there. Perhaps a pinned Photo Ninja TOC would help keep these threads together and easier to reference for we lowly apprentices of this dark art.

 

Actually 'UV light' is a technical oxymoron, light is what we can see as visible, UV is invisible so it is 'radiation' often abbreviated UVR in scientific publications. :D

 

The demonstration of the result of different Photo Ninja Light Source profiles on the false yellow is very instructive. In addition to trying to develop a processing scheme to avoid the purples I, like others am also seeing the intermittent appearance of greens. I particularly seem to get yellow greens on objects that are supposed to render false yellow.

 

While working through a replication of your 27 Feb 2012, Death Valley example with some of my images I chanced upon a nasty looking yellow green dandelion/buttercup replete with Spectralon & color checker recorded with Spectralon in camera WB. This yellow green was present in my in camera jpg, which was recorded along with the RW2 file.

 

Opening the RW2 in PN, I selected light source No Profile and WB mode manual and when balanced on the Spectralon the From Camera green vanished. However green remained after Manual WB with Match Color Temp or Daylight Flash profiles. I do not have a Camera&Lens custom profile on that combination so I cannot say if that would have also gotten rid of the green but I thought it perhaps worth reporting nonetheless.

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Of course UV light is as non-existing as any UV [false] colours, if we take an anthropocentric approach to the matter. However, as we 'see' these subject through the eye(s) of a camera, the notion of light is easier to comprehend. I think there is little opportunity to misunderstand what is intended.
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I particularly seem to get yellow greens on objects that are supposed to render false yellow.

 

There's that phrase again: supposed to.

 

Once again with FEELING this time....what affects the production of UV false colour ??

  • camera (sensor/software/algorithms/Bayer filter/exposure)
  • illumination
    • natural sunlight (time-of-day, time-of-year, altitude, geographic location)
    • artificial flash (type, duration, filters, strength)

    [*]lens (construction/coatings/reflections/hotspots)

    [*]filter (type/thickness/bandwidth)

    [*]raw converter(demosaicing algorithm/wb tool/camera profiles/saturation/contrast/exposure)

    [*]subject (flowers for example may change their UV-signature with age, thus false colours change)

I'm sure I have omitted an entire grocery list of false colour factors which I managed to cough up in other posts somewhere.

Anyway there really is no such thing as a false colour you are "supposed" to get. :D :D :D

Banish that supposition !!!

 

We can only say that there is a range of false colours we usually get - under Bayer filtration and the Baader-U and most white dropper tools - that tends to fall into the blue/yellow/grey and maybe-green palette.

 

I'm thinking that after this week long discussion (it seems like it has been much longer?) -- and in light of (in UV-light of ??) some recent very testy PMs I've received about the blue/yellow/grey palette -- that I will switch to using Black & White renditions of UV work.

Naturally an endless discussion of the proper way to render UV in B&W will ensue on many fronts because B&W has its own can of B&W worms.

Sigh. Oh well. :D :) :)

 

Bytheway -- in-camera white balance is not always accurate. Another huge sigh.

 

I have the worst headache right now full of purple. Or violet. I'm never sure what that colour is named.

 

But JD please post your photo so we can see what you were seeing.

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I particularly seem to get yellow greens on objects that are supposed to render false yellow.

 

There's that phrase again: supposed to.

 

Once again with FEELING this time.... .... there really is no such thing as a false colour you are "supposed" to get. :) :) :D

Banish that supposition !!!

 

Understood, wrote it down 10 times!

I should have said:

I particularly seem to get yellow greens on objects that are supposed to typically render false yellow in the preferred palette.

:D

 

But JD please post your photo so we can see what you were seeing.

 

I won't be able to get to that right away.

I have a very busy weekend, big season opening tournament. Go Tigers!

Remind me next week please and I will insert photos into that post.

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