Photos of blue flowers Log 13.

[gote]

The problem in taking photos of blue flowers is often that they are not only blue but also infrared. Many types of film - and I assume also digital cameras - are more sensitive to infrared than the human eye is. This means that some blue flower might come out pink or purplish. The remedy for this is to use a filter that cuts it out. These filter are usually based on diffraction and look colourless to the eye but keep blue flowers blue.

Another problem lies in that what we see is a function of the colour of the light as well as of the object. Normally the human brain and the chips of the digital cameras sort this out and compensate for the influence of the light. However, the difference in wavelength between violet and red is large and thus flowers in the purple/blue area sometimes come out wrong.

It is difficult to do something about it. The very eager photographer could try to experiment with the kind of light he uses but that is difficult to do in the garden. Once upon a time there used to be different kinds of film for daylight and artificial light. There also used to be filters that allowed the use of daylight film with incandescent lamps. Perhaps the use of such a filter could be the solution. The colours will be wrong but the result after correction back might be better. 

Your photos are excellent Ian. (and we cannot check them against the original  )

Göte 

 

[Ian Y]

Göte 
Thanks for your experience.
 It is the purple colour that I was unable to capture and as you explain the temperature of the illuminating light plays a factor.
I tried varying the white balance setting as well as using sun light and shade but could still not get the colour I see in my head.
In the middle of the night I suddenly had an idea to try a polarising filter to cut out reflected light - I will report back.

[Paul T]

Ian,

I find with my camera that focusing on something else of a totally different colour prior to a picture "resets" the camera.  I do this where I am trying to photograph something blue and find it appearing purple on screen and vice versa.  Often, after focusing on something totally different the camera recognises the flower as a different colour and it is then much more true (or sometimes it gets worse... just try a few times.  ).  Might not work for every camera, but does work at times for mine.  Just thought I'd mention in case it helps.

[David Pilling]

I assume also digital cameras - are more sensitive to infrared than the human eye is.

There's a nice demo, point an infra red remote control at a digital camera and you'll be able to see the beam.

[gote]

Ian,
You must have noticed that some Gentiana especially some strains of sino-ornata look differently in lamplight than in daylight. In this case even the human eye can see the difference.
My suggestion is that a daylight filter would change the overall light temperature towards higher values. This would make everything bluer but after compensating back the excess blue one might be better off.
My own problem is that blue flowers that also have infra-red in the makeup like Ramonda myconi tend to become pink.
I did not know that one can see the beam as David writes.
I would be surprised if a polarising filter would help - but I am sometimes surprised.

David,
i did not know that - very interesting. I will check with my cameras one of these days.
   
Göte

[Paul T]

I find that red flowers with more than a tiny bit of pink in them come out looking pink on my digital camera.  I have a Rhododendron 'Taurus' that I have yet to take a pic that looks satisfactorily red! 

[gote]

Paul,
Have you tried to lower the exposure one stop?
Göte

[ian mcenery]

My experience with my NIkon D70 gives blues as better than real life in some cases leaning toward turquoise. Altering the white balance, bracketing the exposure or using a polariser does not make any difference. I do seem to be able to get some improvement when I use Photoshop in autofix though.

Last year I tried to photo a clematis called Gypsy Queen a sort of Jackmanii type ie sort of the blue side of purple and whatever I did with exposure, filters stc  it came out as red purple so if anyone has got some ideas I would loove to hear about them. Maybe the digital sensors can't deal with a mix of blue and red

Another interesting problem I had the other day was when taking a shot of Rhodo macabeanum at Trewithen Garden in Cornwall. This plant I think is famous for its depth of yellow and the freeness of flowering. The colour was a beatiful yellow not golden but a strong yellow. Having had probs before with yellow flowers I bracketed the shots. All were different but all were washed out in colour. This was strange as narcissus photos were OK.      

[Paul T]

Göte,

I really must learn the manual side of my camera.  I do have the option to hand set things but I tend to just rely on the autuomatic settings.  You're right though, if I messed with the setting myself it would probably fix that particular problem.  At this stage I'm more of a "point and click" type photographer, nothing even vaguely professional about my methods!!    Thanks for the advice.  I'll try it this spring when Taurus is in flower.

[gote]

Ian,
A polarising filter - if it is of good quality - does not change the colour of anything. It does cut out light that is polarized if it is set perpendicularly to the direction of the polarising.
Reflections from surfaces like water, glass or car paint are polarized to a certain extent. How much, depends upon the angle of reclection. Thus a polarizing filter will allow us to photograph into water and to photographe into a house through the window by decreasing the reflections. Polarizing sunglasses will decrease the glare from the hood when driving against the sun and will allow us to see the bottom of a pond better.
The sky is polarized. (Some animals like bees and birds can see this and use it as a navigation aid). For this reason it is possible to use a polarizing filter to darken the sky in a picture. Since the sky usually is a very bright "object" in any picture it will tend to be overexposed and "washed out". For this reason a polarising filter will make the sky look bluer but in reality it is not bluer it is just darker. It is not a change of hue. It is a change of saturation.

I have tried to explain why a blue flower sometimes comes out redder in my first posting. It is because your camera is more sensitive to infra-red than your eye is. The infra red is recorded as red - thus you get a red cast over some flowers.
I suggest reading: http://www.imx.nl/photo/leica/cameratest_m8/m8_part_7_results_with_the_.html
If you want to purchase a filter I suggest googling "IR blocking filter" Those based on interference technique are the best.
Balzers in Liechtenstein used to manufacture a useful filter many years ago but I do not know if it is still in production.
Good luck
Göte

[Ian Y]

Göte
The reason that I thought to try a polarising filter was to try and cut out any reflected light.
My problem is not that my blues are mixed with red but I cannot get the true royal purple colour so I want more red.
I wondered if the red pigment was at a lower level in the petal structure, and what the camera saw was the reflected light from the surface, if I can cut out the reflected light then perhaps the camera will capture the true colour.
If the light improves before the flowers fade I will try it and post the results here.

[ian mcenery]

Gote very interesting to read your comments and also the link. Just goes to show what a challenge getting the right colour can be (as I percieve it anyway).  Any thoughts on why I should have had so much difficulty with some yellow.
I show the photo below with an attempt by me to correct this in photoshop. Please note that I had bracketed this shot +1 and -1 stop and the cameras selection was best

[gote]

Ian and Ian,
My experience (and education) about photography is based on the silver halide processes (fancy word for film is it not  ) There, the most common problem has been the one with the unwanted sensitivity to infrared.

Yellow colour can be yellow only as in the sodium lamp or it can be white minus violet as in the yellow filters used to darken the sky in B&W photography. (Usually perhaps a mix of course).

What follows now is speculation (Or guesses that I hope are educated.    ) If the camera is too sensitive to ultraviolet or near ultraviolet, this will fill in the spectrum from some yellow flowers so that they look whiter. It will probably also make a purple flower more blue.

It is more difficult to check whether the camera is senstitive to ultraviolet in the borderline to visible violet. We have no remote controls working with ultraviolet. Those who have been photographing a long time probably have a yellow filter lying around. What about trying that and then correcting back on the yellow in photoshop??.

There are filters available in shops for amateur astronomers that cut out both ultraviolet and infrared but since these are expensive and this is speculation on my side I would recommend the yellow filter as first attempt.

I also have the problem when photographing purple or really red hepaticas but I have only used foul language as remedy  . This discussion perhaps can make me do something about it.

Göte

PS
The language did not help - I do not recommend it as remedy         

[ian mcenery]

Gote thanks for your comments the yellow of the flower I show above seemed to have more of a blue aura (a cold clear yellow) than a red one (golden)  so some of this seems to make sense. I also use alternative language from time to time when things go wrong but I have found that it does not improve the pictures