The right workflow for using TTL when taking pictures of insects?

A3S

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I practice with TTL when taking (macro) photos of insects outdoors. There is ambient light and the light of the TTL flash. I have to find the right balance between these two light sources.

The insects are visiting flowers on a green plant with widely spaced branches against a distant green background.

I want to find out if 50% ambient light and 50% flash light will result in the right balance.

I wonder if the following workflow is the right approach for that:
  1. I set program mode of the camera to Aperture priority.
  2. I choose an aperture Ax that will give sufficient depth of field.
  3. I set an ISO-value ISOx that with aperture Ax results in a shutter speed of 1/100.
  4. I set program mode of the camera to Manual.
  5. I set aperture to Ax and shutter speed to 1/200.
  6. I set Exposure compensation to minus 0,3 (the flash will not reach the background; I suppose the TTL mechanism will compensate for that with some more light and I want avoid over exposure of the visiting insect).
  7. I set the flash light to TTL.
  8. I take a photo of an insect visiting the plant.
My equipment is: a Nikon D5600 camera, a Nikon AF-S 85mm F/3.5G ED VR DX Micro, two Godox MF12 flash lights, a Godox twin flash light bracket and a Godox X2T-transmitter.
 
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If in #6 you meant "flash compensation", then it sounds like a reasonable workflow. If you are happy with the images, then it is working 😀

If you are not happy with the images, post some examples to demonstrate the issue.

When using flash at a short rage, I find most time is spent figuring out how to soften the light from the flash. It is not the settings but rather the position of the flash and light modifiers (that's a fancy name for a paper towel).
 
I practice with TTL when taking (macro) photos of insects outdoors. There is ambient light and the light of the TTL flash. I have to find the right balance between these two light sources.

The insects are visiting flowers on a green plant with widely spaced branches against a distant green background.

I want to find out if 50% ambient light and 50% flash light will result in the right balance.

I wonder if the following workflow is the right approach for that:
  1. I set program mode of the camera to Aperture priority.
  2. I choose an aperture Ax that will give sufficient depth of field.
  3. I set an ISO-value ISOx that with aperture Ax results in a shutter speed of 1/100.
  4. I set program mode of the camera to Manual.
  5. I set aperture to Ax and shutter speed to 1/200.
  6. I set Exposure compensation to minus 0,3 (the flash will not reach the background; I suppose the TTL mechanism will compensate for that with some more light and I want avoid over exposure of the visiting insect).
  7. I set the flash light to TTL.
  8. I take a photo of an insect visiting the plant.
My equipment is: a Nikon D5600 camera, a Nikon AF-S 85mm F/3.5G ED VR DX Micro, two Godox MF12 flash lights, a Godox twin flash light bracket and a Godox X2T-transmitter.
What I do with my Nikon bodies (currently D40, D7100, Z50, Z5)

Manual exposure mode. Set exposure for the ambient light by selecting the shutter speed and aperture you want. You may want the background a bit darker. If so select a shorter shutter speed - you are probably selecting aperture suitable for your close up subject. Shutter speed needs to be equal too or less than the cameras max flash sync speed.

Ensure flash is in TTL and not Balanced Fill TTL which is the Nikon default and what it tries to do when matrix metering is used.. Not sure if the Godox supports balanced fill but if you select spot metering on you D5600 it should force the issue.

By selecting spot metering the camera will calculate the flash exposure for the subject, which should be under one of the AF sensors (even if focusing manually) and ignore the background. The exposure for the background is determined by your aperture and shutter speed settings.

Dial in some negative flash exposure compensation. For closeups I usually start with -1.0 EV and take a test shot. Depending on the tones of the subject I may end up with a flash exposure compensating anywhere from 0 to -3 EV. I have never needed positive flash EC. I'm not sure if flash exposure compensation works with those Godox units. Easy enough to try.

I tend to get better results setting aperture and shutter speed for the ambient (background) exposure and setting flash power manually rather than TTL, but I usually try TTL first.

Sometimes the close up flash can be a bit harsh, even at low power. A diffusion panel on each flash can help. With the Nikon R1 system I used (two SB-R200 units) panels were included. If you Godox units don't have any you can make crude diffusers using tissue paper. The Godox MF12 Macro kits that are available come with diffusers.

Since the fastest flash sync speed on the D5600 is 1/200s, if your background is very bright, it is possible that it can be overexposed. The D5600 doesn't support high speed sync flash so you would need an ND filter.

Experiment. Have fun.

--
If cameras and lenses can have autofocus then why can't I?
 
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I practice with TTL when taking (macro) photos of insects outdoors. There is ambient light and the light of the TTL flash. I have to find the right balance between these two light sources.

The insects are visiting flowers on a green plant with widely spaced branches against a distant green background.

I want to find out if 50% ambient light and 50% flash light will result in the right balance.

I wonder if the following workflow is the right approach for that:
  1. I set program mode of the camera to Aperture priority.
  2. I choose an aperture Ax that will give sufficient depth of field.
  3. I set an ISO-value ISOx that with aperture Ax results in a shutter speed of 1/100.
  4. I set program mode of the camera to Manual.
  5. I set aperture to Ax and shutter speed to 1/200.
  6. I set Exposure compensation to minus 0,3 (the flash will not reach the background; I suppose the TTL mechanism will compensate for that with some more light and I want avoid over exposure of the visiting insect).
  7. I set the flash light to TTL.
  8. I take a photo of an insect visiting the plant.
My equipment is: a Nikon D5600 camera, a Nikon AF-S 85mm F/3.5G ED VR DX Micro, two Godox MF12 flash lights, a Godox twin flash light bracket and a Godox X2T-transmitter.
Hello,

If you want 50% ambient, 50% flash, you must underexpose (underlighten if you prefer) you subject by 1 stop. If you can, simply use a lower ISO

1 stop means twice less light, so to compensate TTL will add the same amount of light than ambient light. You may then adjust flash power with flash compensation if the flash does not brighten your subject correctly.

By the way, not clear what you mean.
  • Rules 3 and 5 look contradictory. You use 1/100 then 1/200. Unless this is to underlighten by 1 stop ?
  • Exposure compensation has no effect in manual. You can use it to estimate the "underexposure" though it could be slightly wrong. You must underexpose the subject by 1 stop.
 
If in #6 you meant "flash compensation", then it sounds like a reasonable workflow. If you are happy with the images, then it is working 😀
If this is flash compensation, -0.3 will not add more flash power.

So I do not know what the op means...
If you are not happy with the images, post some examples to demonstrate the issue.

When using flash at a short rage, I find most time is spent figuring out how to soften the light from the flash. It is not the settings but rather the position of the flash and light modifiers (that's a fancy name for a paper towel).
 
About compensation at #6:
Since with TTL the camera controls the amount of light emitted by the flash, I assumed that exposure compensation could also be done by/through the camera.

About TTL and not Balanced Fill TTL:
In the menu of my D5600 I can only choose for TTL (and not for variants of TTL). But I can select spot metering (in stead of center metering so far).

About diffusors:
I use Godox MF-12 Dental Diffusor on my MF-12 flash units.

And after more reading about it:
I now realize that Nikon names its TTL as i-TTL, even for the D5600, so there is probably more to it than what follows from a simple formula for adding the missing light not provided by the ambient light as determined by the manual aperture and manual shutter speed of 1/200.

Thanks so far!
 
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If in #6 you meant "flash compensation", then it sounds like a reasonable workflow. If you are happy with the images, then it is working 😀
If this is flash compensation, -0.3 will not add more flash power.

So I do not know what the op means...
In TTL the pre-flash will not reach the background and some parts of the scene will look "dark" to the camera. Therefore, the camera is likely to bump the flash power up trying to brighten the background.

I think I would adjust the actual flash output manually rather than try different flash compression values which might be different for different scenes. It is a balancing game either way, but going fully manual removes any inconsistencies and unknown unknowns of the automation.
 
If in #6 you meant "flash compensation", then it sounds like a reasonable workflow. If you are happy with the images, then it is working 😀
If this is flash compensation, -0.3 will not add more flash power.

So I do not know what the op means...
In TTL the pre-flash will not reach the background and some parts of the scene will look "dark" to the camera. Therefore, the camera is likely to bump the flash power up trying to brighten the background.
Oh ok, was a bit difficult to interpret #6.. Thanks for the explanations

TTL will focus on subject lighting and is supposed to work correctly with a dark background. But it is true that very dark background can have a small impact.

So I agree with what you said, thanks.
I think I would adjust the actual flash output manually rather than try different flash compression values which might be different for different scenes. It is a balancing game either way, but going fully manual removes any inconsistencies and unknown unknowns of the automation.
 
About compensation at #6:
Since with TTL the camera controls the amount of light emitted by the flash, I assumed that exposure compensation could also be done by/through the camera.
Your assumption is probably correct. I don't think the Godox manual mentions exposure compensation since the unit doesn't have an adjustment control on it. Still, with 3rd party units I always test functions to very.
About TTL and not Balanced Fill TTL:
In the menu of my D5600 I can only choose for TTL (and not for variants of TTL). But I can select spot metering (in stead of center metering so far).
Nikon has two forms of i-TTL. When using matrix or center weighted metering it uses what they call i-TTL Balanced Fill flash. The camera attempts to balance flash output between main subject and background.

When using spot metering it uses what they call Standard i-TTL which adjusts flash output for the subject and ignores the background.

Balanced i-TTL often works pretty well but can sometimes produce less than desirable results if there is a big difference between subject and background distance, big differences in subject and background tonality, and some other types of scenes. It may work just fine for your scene. Because Balanced i-TTL tries to adjust for the entire scene even slight changes in framing can effect the exposure if the background changes a bit even if the subject is the same.

Standard i-TTL ensures that the flash output is adjusted just for the subject. You are more likely to get consistent results on your subject. But you need to set your background exposure manually.

You also need to be aware that the Nikon meters want to make your subject middle gray. In Matrix metering if a large portion of the scene is a very dark tone (such as black) you may get some over exposure as it tries make those dark areas more gray. If a large portion of the scene is very light (such as white) it may underexpose.

When using spot metering the same thing can happen, but relative to the subject under the focus sensor rather than the entire scene. You can address this by dialing in negative exposure compensation in the first case and positive in the second case if the image looks wrong.

For the 50:50 balance you were looking for -1.0 EV Flash Compensation is a good start. But depending on the tones in your subject you may need alter that. If the subject insect is a light tone, such as a white butterfly, you may need a lower negative value like -0.3 or 0. If it is really dark like a black carpenter any you may need a higher negative number like -1.7 or -2.0. You can experiment. With experience you may find that you get pretty good at dialing a suitable Flash EC right away.

Depending on the scene and framing, including distance between subject and background, you may get the same results using matrix metering, and thus i-TTL Balanced, and spot metering, and thus i-TTL Standard. Or the differences may but subtle or obvious. But I find that I get more consistently repeatable results across a wide range of scenes using spot metering/i-TTL Standard.

If you are not getting good results with i-TTL you can fall back to selecting flash power manually. I have a lot of butterfly shots where I have manually set flash output to 1/64 or 1/128 because I wasn't getting great results with either type of i-TTL.
About diffusors:
I use Godox MF-12 Dental Diffusor on my MF-12 flash units.

And after more reading about it:
I now realize that Nikon names its TTL as i-TTL, even for the D5600, so there is probably more to it than what follows from a simple formula for adding the missing light not provided by the ambient light as determined by the manual aperture and manual shutter speed of 1/200.
You can set up some test scenes where you have more control over the subject, background, lighting, subject and background tones, etc and experiment with manual exposure versus aperture, priority, matrix metering (and i-TTL Balanced) vs Spot metering (i-TTL Standard), and different levels of Flash EC or setting flash output manually to see how your camera/flash system produces different results. This will help develop some confidence with your preferred way of operating and find a workflow that works best for you.
Thanks so far!
--
If cameras and lenses can have autofocus then why can't I?
 
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If in #6 you meant "flash compensation", then it sounds like a reasonable workflow. If you are happy with the images, then it is working 😀
If this is flash compensation, -0.3 will not add more flash power.

So I do not know what the op means...
In TTL the pre-flash will not reach the background and some parts of the scene will look "dark" to the camera. Therefore, the camera is likely to bump the flash power up trying to brighten the background.
Oh ok, was a bit difficult to interpret #6.. Thanks for the explanations

TTL will focus on subject lighting and is supposed to work correctly with a dark background. But it is true that very dark background can have a small impact.

So I agree with what you said, thanks.
I think I would adjust the actual flash output manually rather than try different flash compression values which might be different for different scenes. It is a balancing game either way, but going fully manual removes any inconsistencies and unknown unknowns of the automation.
There is a difference, sometimes subtle, and sometimes much more noticeable, between Nikon's i-TTL Balanced Fill and i-TTL Standard flash. The camera uses Standard when spot metering is selected; Balanced when matrix or center weighted is used. Standard ignores the background so it wont adjust flash output to try to balance subject and background exposure.

Using spot metering (and this i-TTL Standard) and setting background exposure manually removes some of the inconsistencies of the camera's automation. Of course going all manual removes all of the variability of the the automation.
 
If you want "50% flash / 50% ambient", aim for a background exposed between -1 EV and -2 EV without flash. Then let the TTL do its job on the subject.
 
If you want "50% flash / 50% ambient", aim for a background exposed between -1 EV and -2 EV without flash. Then let the TTL do its job on the subject.
My logic was:
  • the camera is controlling the amount of light that’s being emitted by the flash;
  • I want (for example) a balance between ambient and flash light of 50-50%;
  • given the aperture for sufficient dept of field I let determine the camera how much ISO is needed at a shutter speed of 1/100 using only ambient light;
  • then I set manually this aperture and ISO, and set shutter speed to half of 1/100 = 1/200, so I use 50% of the ambient light for the total amount of light the camera needs;
  • then the flash controlled by the TTL-mechanism of camera and flash unit must supplement this light with the missing 50% of total light needed.
Here I have not taken into account a more complex algorithm in the logic of an intelligent TTL program/mechanism as suggested by the name i-TTL as used by Nikon.
Apart from this, correct me if I'm wrong.
 
Here is the result of a little test following the workflow mentioned earlier, except I set the exposure compensation to minus 0.7 instead of minus 0.3.

705b0f5f18ec49c0ae1ca666a60b98c2.jpg

029b27443eba4b16a89fa2a565d26fa3.jpg

c3ed6bfa344c4762a4eec430a8662172.jpg

Depth in the object is missing in this test, but as expected the background is not black but somewhat darker than the object, so I assume the flash provided an extra amount of light and not all the light.
 
Hi,

One of the main purpose of flash iis to avoid grainy pictures.

Here you use ISO 12800... Well maybe this is just for your test but I am surprised you could not find better settings.

Chris
 
@Chris

Yes, that is a point of concern. Sometimes I will choose for more flash light and less ambient light or a lower ISO value and a larger aperture.

But till now my experience is that I lose more due to a larger aperture and less depth of field than by graininess due to a high ISO-value when taking pictures of for example bees and bumblebees.
 
Your workflow is on the right track, but remember that flash vs ambient balance isn’t a fixed 50/50 it depends on your settings. Ambient is controlled by shutter/ISO/aperture, while flash is mainly aperture/ISO. Try exposing the background a stop under ambient (manual mode), then let TTL fill the subject. Adjust flash exposure comp if the insect looks too bright or dark. This usually gives a natural look with controlled highlights.
 
Your workflow is on the right track, but remember that flash vs ambient balance isn’t a fixed 50/50 it depends on your settings. Ambient is controlled by shutter/ISO/aperture, while flash is mainly aperture/ISO. Try exposing the background a stop under ambient (manual mode), then let TTL fill the subject. Adjust flash exposure comp if the insect looks too bright or dark. This usually gives a natural look with controlled highlights.
Thanks.

After several shots my experience is that it works as you say.
Except sometimes in a shot where a lot of white fills the frame, such as of a white flower. Than the result is sometimes that the image is seriously overexposed. Why? Maybe I have to discover more of working with TTL? Or the combination of camera (Nikon 5600), TTL and Godox flash (X2T transmitter for Nikon and 2 x MF12 flash light) does not work well in every situation?
 

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