How do you select the color temperature of your strobe(s)?

[Architeuthis]

I have questions regarding the selection of the color temperature of a flashlight, especially to people who change the temperature, depending on conditions:

 

My understanding is that for photos that are lit (almost) exclusively by a flash, e.g. macro, color temperature of the flash is unimportant as the temperature of the raw file can be adjusted delibertately in postprocessing, e.g. LRc...

 

The color temperature of a flash becomes important, when ambient light and artificial light from a flash get mixed. e.g. WA. The warmer the color temperature, the less adjustment of the raw file is required in order to get the correct WB for the foreground subject that is lit by the flash. Hence, the background color, e.g. open water, is less influenced by the WB procedure and the blue will be more natural...

 

 

 

Here is an example photo that I produced on my last trip to the Carribean, using two Inon Z330s with standard diffusers. The color temperature of these flashes is at 5500K. WB was adjusted to show the correct colors of the reef shark (Carcharhinus perezi) to the left in the foreground:

Sony A7R5, Sony 20-70mm @20mm, 1/160s, f/9, ISO 400, 2*Z330:

 

I guess, if I would have used diffusers to warm up the color temperature to 4500K I would have a "better" blue in the background, i.e. less "greenish" cast?

 

 

How do you adjust the color temperature of your flashes and what temperature is the optimum for what conditions?

 

 

 

Thanks, Wolfgang

 

Edited May 6 by Architeuthis

[Interceptor121]

Warmer temperature of your strobe means the blue gets more saturated

it is not about the tint but about the color temperature

 

I have tried all sorts of filters 4600 4900 5500 ambient light and today I find my Sea and Sea YS-D2J 5250 just perfect and would not go any different

This is because you can use masks to get the blue you want if there is an issue with it

 

Some strobes have natively a look that is nicer than others, the key is to get the natural color without having to play with diffusers or filters

[Chris Ross]

I use INON Z-240s and have generally used the 4600K diffusers that came with the units in tropical blue waters and I've been happy with the results.    I have not done extensive comparisons using different diffusers though.  Agree it's about colour temperature balance, not tint.  If you are using INON strobes, diffusers I think are a given whether they are the standard ones or the warming diffusers.

For myself I would rather get it right in camera, there are various ways of addressing the blues without impacting upon the main subject including masks, but If I can get away without drawing masks on my images I will, depending on subject they can be fiddly and you always risk edge effects around your subject.

[ChrisH]

Color temperature of a strobe is an interesting topic.

 

Basically, a warmer color temperature of the strobe light will give you a nicer color of the blue water in wide-angle shots. The automatic white balance tries to contain an average of I think 18-19% grey. If you hit the foreground with a warmer light color from the strobe, the white balance in camera "counters" this with getting the whole image a cooler color, giving a better blue right out of the cam. The effect does mostly show if a good portion of the image is lit with the strobe (affecting the white balance of the whole image), so you can see it more in reef scenes or something like that.  

 

I think it can be achieved in postproduction, but it can sometimes be difficult. I found the colors look best if you get it right in camera, without having to change the hue and saturation of the blue in the RAW converter. But that is only my experience. 

A warm color temperature is one element of a good quality of light on a strobe (but not the only one). And if you ever have used a strobe with a really good quality of light (Seacam, Retra) you will instantly see the difference to other strobes... it really can transform wide-angle pictures! And you might never want to go back 😉 

The quality of light is the key feature of a strobe in my opinion and I am often astonished how people will discuss recycle time and guide numbers, just to eventually end up with unpleasant light (been there, done that 😉 ). 

 

If you have different diffusors, I would for wideangle always go for the warmer color temperature. For freshwater, this can be different, as you want to get a pleasant green water color and not blue. But I don't dive in fresh water and have therefore no experience in what color temperature ist best for freshwater. 

 

In this particular image in the first post the effect of a warmer strobe or diffusor might not have altered the background color too much, as only a small portion of the picture is lit with flash.

[Adventurer]

I am amazed by the fact that shooters discuss this in depth who use Lightroom at the same time!

 

.. noting the fact that bloody LR will reset and flatten your raw files upon import and you have to work yourself backwards on to get what you saw on your cameras LCD underwater.

 

Strobe Color Temperature is highly overrated as it will just apply to 

- white balance = AUTO
- file format = JPEG

shooters who want to be done when they exit the water.

 

The following will therefore just apply to a certain type of underwater photographer:

- green water = cooler strobe temp 

- blue water = warmer strobe temp

is slightly beneficial for rendering better blue or green background in AUTO WB.

 

The logic and scientific approach is much different:

1.) buy the strobe with the coolest color temp 

2.) manual white balance onto that strobes color temp or set the camera to a fixed Kelvin Value of your choice, measurement

 

why?

- get the same or even better effect as with AUTO WB

- utilize the fact that you are bringing optimized photon energy into the water

 

Kelvin Values can be viewed as the integral under a nanometer color spectrum curve measured.

 

The warmer your light strobe, the more absorption you will suffer from in water. With increasing distance the warm light is the first to get absorbed. Basically you are wasting a lot of energy and battery power trying to don quichotte the water column.

 

Keep in mind that this is not true for very close macro distances, where high CRI and low Kelvin values are considered to be beneficial.

[TimG]

In all the years I’ve been doing underwater photography, I don’t think I’ve ever given thought to the colour temperature of my strobes: Nikonos, then Inons and now Retras. 
 

I’m not sure what that says about me or my images! 

[Chris Ross]

1 hour ago, Adventurer said:

I am amazed by the fact that shooters discuss this in depth who use Lightroom at the same time!

 

.. noting the fact that bloody LR will reset and flatten your raw files upon import and you have to work yourself backwards on to get what you saw on your cameras LCD underwater.

 

Strobe Color Temperature is highly overrated as it will just apply to 

- white balance = AUTO
- file format = JPEG

shooters who want to be done when they exit the water.

 

 

This is not the reason people wish to use warmer strobes.  The reasoning is that a warm strobe when white balanced back to daylight colour balance will render the water bluer.  The water is not illuminated by the strobe so it has no impact on the water directly.   You can't get this effect by just white balancing cooler as the subject will then be too blue.   It's the same problem you get for example shooting flash of for example a sunset with with a flash lit foreground subject.  The WB will only be "right" for one subject as you are mixing 5000K flash light with 2000K sunset light.   The WB can only be "right"for one - not both.

 

Not sure if all cameras do this but as I understand it at least some set the WB to standard colour temperature for flash assuming it will match and produce pleasing skin tones.  So Auto WB when shooting flash defaults to 5000K or whtever the manufacturer uses.

 

Tend to agree on LR, I don't use it but as I understand it  you can set it up to use your WB and other settings as a preset to give you a starting point.

[Architeuthis]

First, let me thank all of you for the interesting comments...👍

 

Until now I was using my strobes (Z-330) at color tempearture as they come from the factory (5500 K). Two weeks ago,  I pre-ordered two Backscatter HF-1 strobes with different types of diffusers (6500 K, 5500 K and 4500 K) and am glad to read how people use such filters (or some, not at all), to have a first orientation for my own experimentation...

(I, personally, am convinced that it is better to adjust the color temperature relation between artificial and ambient light already before the light hits the sensor (this was the reason for per-ordering two HF-1's plus filters). There will be always corrections in post-processing, also using masks, but the smaller such manipulations are, the better the final outcome will be (this is at least my hope))...😊

 

 

Wolfgang

Edited May 13 by Architeuthis