photography questions and answers
The past few days’ posts were all set to be part of the on-going question and answer theme where I look at search engine queries, and directly answer a selection of 10 questions. But they all expanded into something longer that warranted individual posts:
- available light vs fill-flash
- best fill flash settings
- exposure metering modes
01) do I need to adjust my camera exposure with flash photography
Interestingly phrased – and the answer is, yes, to an extent. To an extent you don’t need to adjust your camera exposure when you use flash photography .. IF (and a big if) .. IF your ambient exposure is low enough.
With this wedding portrait, my camera settings were 1/50 @ f4.5 @ 800 ISO, using TTL bounce flash.
The flash entirely dominates. It is in effect the only light source here. Since my ambient light levels are so low, I could’ve had a whole range of combinations of camera settings, and the TTL flash would still have taken care of the exposure.
In that sense, I need not adjust my camera settings. I could take numerous photos, and the TTL flash technology would take care of my exposure. It’s now just up to me to make sure my composition and timing and direction of light is good. So to a large extent, I could ignore my camera settings. But this only works when the ambient light levels are low. The moment the ambient light becomes more prominent .. eg, in brighter light, or because of my camera settings .. then I need to think more carefully about how to balance my flash with the available light.
This somehow segues into our next question, by way of contrast …
With manual flash, we have 4 controls for the flash exposure – aperture, ISO, power, distance. SInce the Sunny 16 rule tells us that we’re most likely in the region of: 1/250 @ f11 @ 100 ISO … this means we have to get f11 @ 100 ISO out of the flash, or more. We only have the flash’s power and distance-to-the-subject to work with then to get that f11 @ 100 ISO (or there-abouts). Since we’re probably working at full power anyway, or close to it … this then only leaves us the distance to work with. In other words, you have to get the flash close enough to your subject to give you that f11 @ 100 ISO (or more). So for us speedlight shooters working in bright sun, it is usually not so much the flash output per se, but rather the distance between the flash and the subject. Oh, and while we’re on that topic, going into High Speed Sync mode will not solve your problem, but will worsen it … unless you have plenty juice to spare in your speedlight. Taking your shutter speed over maximum flash sync speed into high-speed flash sync, means less flash power.
03) aperture controls flash exposure
Sometimes I feel like Don Quixote, tilting at this particular windmill … but really, aperture only controls flash exposure with manual flash. For TTL flash, there is an entirely different process at work. We really need to differentiate between TTL flash and manual flash, since for TTL flash, aperture does not control the flash exposure. When you hear someone say, “aperture controls flash exposure”, you just need to add the mental asterisk there yourself … *only for manual flash.
04) lens hoods, yes or no
Dude! Yes! Unequivocally and indubitably, the use of lens hoods are necessary. In fact, lens hoods should be mandatory.
05) how to avoid shadows when using flash vertically
We can avoid that typical hard flash shadow, by bouncing our flash. Or using some kind of light modifier like an umbrella or softbox. But the method that is the most easily available to us indoors, is simple bounce flash.
If you do need to use flash directly, and need to shoot vertically, then your best option is a rotating flash bracket.
06) why does TTL bounce flash need extra flash exposure compensation?
In theory, TTL flash exposure shouldn’t differ whether we shoot straight-on or with bounce flash. Keeping in mind that we need to stay within the range that the flash is capable of working in. Quite often we might be too close to our subjects when we shoot at a wider aperture. (Check the scale on the back of your speedlight.)
In practice we could very well find that we need to bump up the FEC a notch or two when bouncing flash. I take it to just be “one of those things”. Camera make and models vary. The algorithms they use to calculate flash exposure, all vary. So we could very well find that somehow we need more FEC with bounce flash. It’s one of those things we need to be aware of for our specific camera and flash, and then automatically adjust our settings for.
So why does TTL bounce flash need extra FEC some times? I don’t know. But I do know my cameras and adjust them accordingly, and get on with the photography.
07) how do you exposure for your subject? skin tones two stops up
With the Zone System, Caucasian skin tones are usually placed at Zone VI / Zone 6 .. which is one stop up from middle grey / Zone V. Very light skin tones might be placed at 2 stops up from middle grey. ie, Zone VII. However, skin tones vary a lot, and we need to keep that in mind.
Now, applying the classic Zone System directly like this – placing skin tones by adding a stop more exposure – is something we could do with B&W photography where we have exact control over the choice of film, processing of the film, and the printing stage. For digital, metering off Caucasian skin tone, and then adding 1 stop more exposure, could very well lead to over-exposure. Certainly, 2 stops up from a mid-tone with a digital camera would push the histogram right to the edge or beyond. Over-exposure.
Therefore, metering off skin tones is something we could do, but we’d have to evaluate how light or dark the skin tones is that we’re metering off.
08) what is the flash power setting for off-camera flash without a softbox
It’s impossible to give a direct answer to this. It really depends on what your ambient light is doing, and what you are trying to achieve with flash.
That said, metering for off-camera flash is most easily done with a flash-meter. If you don’t have a flash-meter, then the flash’s Guide Number will tell you what you need to know. Or just look at the distance scale on the back of your flash.
Since manual flash is dependent on:
- distance of your flash from your subject
- power setting
… it means we need to adjust our flash’s power output for the chosen aperture / ISO / distance combination. The distance scale on the back of the flash will tell us what we need to know to get close to correct exposure for our manual flash.
I feel compelled to make screengrabs of some of these search engine queries, just in case people might think I am being cute and just making this stuff up:
09) what is the best thing about camera companies
Well, for me, the best thing about camera companies, is that they make the toys we all love so much!
10) And as always, the final one is a funny … by virtue of this blog’s name
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If you find these articles interesting and of value, then you can help by
using these affiliate links to order equipment & other goodies. Thank you!