[Tonytee]

I am having difficulties in reproducing the color, Light Blue. My wife's African Violet Plant Flowers are a light blue with just a tinge of Purple around the Stamen and the

entire flower turns out a dark purple. I have tried various lenses and cannot get what I am shooting for. I even tried another make of gear and same problem. Please

see the uploaded image. Again, the flowers are a Light Blue. Please below image for EXIF Data. Thnx. Tonytee.


Camera Make PENTAX
Camera Model PENTAX K-7
Date Taken 2023-01-02 10:23 PM
Resolution 977 x 700 pixels
Flash Used No
Focal Length 135.0mm (35mm equivalent: 202mm)
Exposure Time 1/60s (0.017)
Aperture F/8.0
ISO Equivalent 100
Exposure Bias 3.00
White Balance Auto
Metering Mode Pattern
Exposure Manual
Exposure Mode Manual
Focus Range Distant
JPEG Quality 100
Lens ID A Series Lens

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Last edited by Tonytee; 01-03-2023 at 12:40 AM.

[Medex]

Probably you should set proper white balance using 18 percent gray card. If this not help, then postprocess RAW file in editing software.

[kypfer]

This could be one of those instances where the light reflected contains an element of ultra-violet, which the eye doesn't register but the camera does, so may be one of those rare occasions in modern photography where a genuine old-fashioned UV filter might be useful!
However, I'd disagree with the idea of using an 18% grey card for white-balance settings.
Grey cards are for exposure settings, white card is needed for white-balance settings, (the clue's in the name!)
Good luck

[Medex]

This could be one of those instances where the light reflected contains an element of ultra-violet, which the eye doesn't register but the camera does, so may be one of those rare occasions in modern photography where a genuine old-fashioned UV filter might be useful!
However, I'd disagree with the idea of using an 18% grey card for white-balance settings.
Grey cards are for exposure settings, white card is needed for white-balance settings, (the clue's in the name!)
Good luck

Reasonable

[mlag]

Why exposure bias 3 stops? Looks a lot...
On camera I think this is the +/- EV button.
If you did set it 3 stops darker, I can understand that light violet gets into dark violet....would also be consistent with all lenses as it is a camera setting.
It seems to confirm my general impression of a dark image....

Is it only on this scene or also other (blue...violet) stuff ? Try a color chart or rainbow or so...

Can you try green mode on top dial iso manual, it overrides (other , maybe accidental) settings on camera?
Awb is ok in exif, maybe some jpg conversion or warm mode , sometimes people activate accidently stuff on the 4way (up-down-left-right button) button controller on back of camera..... right button settings?

[UncleVanya]

Why exposure bias 3 stops? Looks a lot...
On camera I think this is the +/- EV button.
If you did set it 3 stops darker, I can understand that light violet gets into dark violet....would also be consistent with all lenses as it is a camera setting.
It seems to confirm my general impression of a dark image....

Is it only on this scene or also other (blue...violet) stuff ? Try a color chart or rainbow or so...

Can you try green mode on top dial iso manual, it overrides (other , maybe accidental) settings on camera?
Awb is ok in exif, maybe some jpg conversion or warm mode , sometimes people activate accidently stuff on the 4way (up-down-left-right button) button controller on back of camera..... right button settings?

That’s a plus 3 not -3 exposure bias. It certainly doesn’t look like it however. The older dslr Pentax models often struggled to reproduce reds without overexposure/oversaturation. I wonder if that’s involved - blue plus red is purple. I’d like to see the histogram of the raw file if available.

[texandrews]

So, I think you need to try to shoot some raw images with a color card---such as a Macbeth. But I will also say that even doing that you will have to expend some time and effort to dial in your color. Sensors render colors their own way, and truly 100%accurate color can be tough to achieve.

[OrchidJulie]

In my (admittedly limited) experience, this blue/purple color is very, very difficult for digital sensors to capture and record accurately. In my former life, I dealt often and regularly with official flower photographers connected to the American Orchid Society, whose job it was to accurately capture AOS-award winning orchid flowers. All of them lamented the inaccuracy of the sensors in their equipment (mostly Nikon and Canon, but some other brands as well) to correctly record flowers in this color range. I had the same issues doing in-house catalog images of similar flowers...none was correct SOOC.

So it isn't anything you're doing, Tony.

[MossyRocks]

In my (admittedly limited) experience, this blue/purple color is very, very difficult for digital sensors to capture and record accurately.

I believe this is the case here. There are colors that exist outside of the RGB or CMY color spaces that just can't be accurately reproduced by devices that operate in them. From what I remember various shades of violet fall into that area. Here is an explanation I found after a quick search that should help shed some light on the issue. I figured there would be a wikipedia article on this as well that might better show things and did find that here so hope this helps too.

[Tonytee]

Okay, many thanks for all the helpful hints, suggestions and instructions. After carefully following every instruction, this is the best I could come up with. Please see the

EXIF Data below the image. Another observation: After each snap, the flowers show up perfectly in Light Blue on the rear screen however, they show up purple when

uploaded. ??? I checked the resolution and settings on my monitor and all is kosher, no problems. I will also upload an image taken of fabrics my wife uses, including one

of Light Blue. Many thanks for the assistance. Please view EXIF Data below the flower image. These are RAW Files.

Tonytee.






Camera Make PENTAX
Camera Model PENTAX K-7
Date Taken 2023-01-03 05:10 PM
Resolution 1054 x 700 pixels
Flash Used Yes (manual)
Focal Length 200.0mm (35mm equivalent: 300mm)
Exposure Time 1/60s (0.017)
Aperture F/8.0
ISO Equivalent 100
White Balance Auto
Metering Mode Pattern
Exposure Manual
Exposure Mode Manual
Focus Range Distant
JPEG Quality 100

---------- Post added 01-03-23 at 06:32 PM ----------

Fabrics my wife works with. Notice how awesome all the Light Blues turned out. Please see EXIF Data below image. Thanks again, Tonytee.





Camera Make PENTAX
Camera Model PENTAX K-7
Date Taken 2023-01-03 04:56 PM
Resolution 700 x 800 pixels
Flash Used Yes (manual)
Focal Length 135.0mm (35mm equivalent: 202mm)
Exposure Time 1/60s (0.017)
Aperture F/5.6
ISO Equivalent 100
White Balance Auto
Metering Mode Pattern
Exposure Manual
Exposure Mode Manual
Focus Range Distant
JPEG Quality 100

---------- Post added 01-03-23 at 06:37 PM ----------

Here is some help in understanding the color Violet. Makes sense as Julie so aptly described as to why it is difficult to accurately replicate.


What is the color Violet? - Google Search

[K-Three]

Is this under mixed lighting? Combination of daylight and indoor (tungsten, CFL and/or LED?) Get it to a single light source if you can.
The +3 over exposure is likely part of the issue, and if the original is a JPEG (I see "JPEG Quality 100" in the EXIF), there may be some baked in processing that can't be undone. For critical work I like to work with RAW.
I'd try it with a known color reference, neutral gray or white, in the frame, in the same light as the flowers, and use the neutral eyedropper tool in your photo editor to start the correction process, making the neutral card neutral (white or grey) on screen. See where that puts you for the flowers. You may need some more tweaks, but this should get you close.
Bracket your exposures too, from about 2 over to 1 under, in half stops,
Shoot with the color reference card in and out of the frames, make the corrections to the referenced image, then copy the corrections to the frame with the same exposure, but no color reference in it.

Your reference card does not need to be anything fancy, even a white sheet of printer paper should do the trick. You just need something you can tell the software is neutral. But it does need to be placed in exactly the same light as the flowers.

Your first image shows no flash, second w/Flash,

Potentially lots of frames exposed to test it, but you should be able to drive this issue to ground with one session of testing.

Your first image shows no flash, second w/Flash, need to reduce variables to get meaningful results

[Tonytee]

Is this under mixed lighting? Combination of daylight and indoor (tungsten, CFL and/or LED?) Get it to a single light source if you can.
The +3 over exposure is likely part of the issue, and if the original is a JPEG (I see "JPEG Quality 100" in the EXIF), there may be some baked in processing that can't be undone. For critical work I like to work with RAW.
I'd try it with a known color reference, neutral gray or white, in the frame, in the same light as the flowers, and use the neutral eyedropper tool in your photo editor to start the correction process, making the neutral card neutral (white or grey) on screen. See where that puts you for the flowers. You may need some more tweaks, but this should get you close.
Bracket your exposures too, from about 2 over to 1 under, in half stops,
Shoot with the color reference card in and out of the frames, make the corrections to the referenced image, then copy the corrections to the frame with the same exposure, but no color reference in it.

Your reference card does not need to be anything fancy, even a white sheet of printer paper should do the trick. You just need something you can tell the software is neutral. But it does need to be placed in exactly the same light as the flowers.

Your first image shows no flash, second w/Flash,

Potentially lots of frames exposed to test it, but you should be able to drive this issue to ground with one session of testing.

Your first image shows no flash, second w/Flash, need to reduce variables to get meaningful results

Thank you very much. Tonytee. )

[rpjallan]

You have still used Auto White Balance!?!

[Tonytee]

In my (admittedly limited) experience, this blue/purple color is very, very difficult for digital sensors to capture and record accurately. In my former life, I dealt often and regularly with official flower photographers connected to the American Orchid Society, whose job it was to accurately capture AOS-award winning orchid flowers. All of them lamented the inaccuracy of the sensors in their equipment (mostly Nikon and Canon, but some other brands as well) to correctly record flowers in this color range. I had the same issues doing in-house catalog images of similar flowers...none was correct SOOC.

So it isn't anything you're doing, Tony.

A great many thanks, Julie. As always, very helpful.

Tony

---------- Post added 01-03-23 at 08:08 PM ----------

You have still used Auto White Balance!?!

Yessir, as is stated in the EXiF Data. Thank you. )

Tonytee.

---------- Post added 01-03-23 at 08:11 PM ----------

Okay, call me a traitor if you wish. I decided to go to my Canon gear and I believe this is as close to the actual, real time color as I am going to get. The only oversight on
my part was to forget to set the camera to RAW. I do like the way this turned out. Please view EXIF Date below the image.

Many thanks, Tonytee.






Camera Make Canon
Camera Model Canon EOS 7D Mark II
Date Taken 2023-01-03 07:55 PM
Resolution 1050 x 700 pixels
Flash Used Yes (manual)
Focal Length 135.0mm (35mm equivalent: 389mm)
CCD Width 12.49mm
Exposure Time 1/60s (0.017)
Aperture F/5.6
ISO Equivalent 100
White Balance Manual
Metering Mode Spot
Exposure Manual
Exposure Mode Manual
JPEG Quality 97
Lens ID Canon EF-S 18-135mm f/3.5-5.6 IS STM P.S. Every one of these shots were taken with the use of a tripod. Cheers, Tonytee.

[UncleVanya]

A great many thanks, Julie. As always, very helpful.

Tony

---------- Post added 01-03-23 at 08:08 PM ----------



Yessir, as is stated in the EXiF Data. Thank you. )

Tonytee.

---------- Post added 01-03-23 at 08:11 PM ----------

Okay, call me a traitor if you wish. I decided to go to my Canon gear and I believe this is as close to the actual, real time color as I am going to get. The only oversight on
my part was to forget to set the camera to RAW. I do like the way this turned out. Please view EXIF Date below the image.

Many thanks, Tonytee.






Camera Make Canon
Camera Model Canon EOS 7D Mark II
Date Taken 2023-01-03 07:55 PM
Resolution 1050 x 700 pixels
Flash Used Yes (manual)
Focal Length 135.0mm (35mm equivalent: 389mm)
CCD Width 12.49mm
Exposure Time 1/60s (0.017)
Aperture F/5.6
ISO Equivalent 100
White Balance Manual
Metering Mode Spot
Exposure Manual
Exposure Mode Manual
JPEG Quality 97
Lens ID Canon EF-S 18-135mm f/3.5-5.6 IS STM P.S. Every one of these shots were taken with the use of a tripod. Cheers, Tonytee.

Tony this image used a manual white balance. Have you tried the same on the Pentax? Also this is a manual exposure. Have you tried a similar exposure on the Pentax?