Category Archives: Learning

KISS – Keep It Simple, S.

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This picture shows that you do not need a studio with much equipment, necessarily.

I used a Canon 1D Mark IV camera with a 580 EX II speedlite.

And that’s it. Really.

I had the camera on 400 ISO, manual, 1/60th second, f/4. TTL did the rest with the flash.

The flash which was of course pointed behind me, giving “light from 45 degrees above”. Leading to pictures like the one above, and this:

Which when you zoom in enough shows you The Man In The Pupil:

..which of course is me.

Can you see how my flash aimed backward makes a pattern on the ceiling that looks like an umbrella? That’s the  entire point!

Sometimes very simple equipment is al you need for professional work.

RGB?

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Adobe or sRGB? You may have wondered how to set up your camera in this regard. Look through its menus and the choice of colour space will come  up.

This question means “how shall I translate the colours to bits when making a JPG file”.

So what determines your choice?

  • AdobeRGB has more colours but can look very bad on a PC, on the web, or when printed on a cheap printer.
  • sRGB has fewer colours but is optimised to look good on  a computer screen, cheap printer, etc.
  • See above: “…when making a JPG file”.  It is only important when you are shooting JPG.

So the answer is:

  • When shooting JPG, use sRGB
  • Only change to AdobeRGB if the publication you are shooting for says you should use that colour space.
  • When shooting RAW the choice is irrelevant (so set it to sRGB too).

Simple. Like so many things.

And this also represents one of the many advantages of shooting RAW: not ahving to worry about such things as colour space, as they are set later, when the JPG is generated.

Alu Gobi

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I shot a food party tonight, for a glossy magazine. This included, of course, some food shots.

My setup was simple:

One 430EX flash in an umbrella above the food, and one 430EX direct flash with grid side/behind the food.

The camera: a Canon 1Ds MkIII with a 100mm f/2.8 EF Macro lens, with a 580EX flash fitted to drive the other two flashes. I set the camera to manual, f/8 at 1/125th second, 200 ISO, and used wireless E-TTL to drive the external flashes.

The shots: like this one of an Alu Gobi dish (it was freshly cooked Indian food):

See the steam?

And the food? Delicious.

Expose to the right

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What is this “expose to the right” thing we keep hearing about? And do I expose to the right?

A sensor can distinguish varying light levels. Say, for the sake of argument, 100 (the actual number does not matter. A JPG has 255 levels per red-green-blue colour, for example. A sensor can pick up more. But for this discussion, let’s just assume 100).

A picture will be a mix of dark and light (unless it is all one shade).

So let’s assume I am taking a picture of some normal scene that goes from dark to bright.

Ideally, I will want this scene’s sensor data to contain everything from “0” pixels (black) all the way up to “100” pixels (bright white). If I grossly underexpose it, it will be mainly black pixels (level 0), with some lighter pixels (say, between 0 and 10).  If I overexpose it, I’ll get maybe pixels between level 90 and 100.

So for a normal scene, it’s clear, I will want between 0 and 100. The histogram will stretch from left to right.

Now assume a dark scene, e.g. a nightscape. The actual scene may only contain dark stuff – from black to mid grey, say. So exposing it “realistically” would give me pixels from 0 to 50. And when I analyse it, there would be 50 levels. Or let’s assume I have a cave, where it’s so dark it only contains black to very dark. Real levels maybe 0 to 5.

So if I expose to give me a realistic histogram, it would only have five levels of black in the picture. Not much detail in five levels of black. Posterisation (that blocky stuff in areas that change brightness gradually) could easily occur. Also, low-level electronic noise would be hard to distinguish from signal (“The signal to noise ratio is low”, we say).

But if I expose that more (e.g. by opening the aperture or increasing shutter opening time), I would get, say, 0 to 80 levels of signal. Yes, the picture would look wrong – all bright – but if I do it that way I get 80 levels of black. I.e. I would preserve a lot more detail. I would of course need to reduce the levels again later in Lightroom or Photoshop, but I could do that in a way that allows me to choose which detail level to show.

And importantly, reducing the exposure also reduces the noise in that exposure (“the signal to noise ratio is higher”).

But too far, and we lose detail in the highlights (we hit the right side of the histogram).

So by “exposing to the right” and then reducing the exposure in post-production we:

  1. Reduce any posterisation
  2. Increase the signal-to-noise ratio
  3. Create a little more work for ourselves later
  4. Run the risk of exposing too far to the right – blowing out highlights.

So do I do this?

Well, I am not religious about it. Yes, I will often expose to the right. Willems’s Dictum says “Bright Pixels Are Sharp Pixels”. So as long as I can be sure I do not overexpose, I will go slightly brighter. I will check on my RGB histogram.

But not religious, because

  • Our cameras will often do a bit of this themselves, try to fill the available bit space.
  • I want to avoid too much extra work.
  • I might blow out highlights.
  • I feel bad about my skills if I look at “too bright” images.

So I do this in moderation.

Above all, though, I avoid exposing to the left, or underexposing. So you might summarise my workflow as “I always try to expose sufficiently to the right”.

Open wide:

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How do I know that this picture (taken at a recent magazine shoot) was taken at f/2.8?

Given the lens (a 16-35mm f/2.8 lens), I look at the shape of the out-of-focus lights in the background. If the aperture was stopped down, they would be hexagonal or octagonal. Round out-of-focus spots means the lens was wide open: f/2.8, therefore.

Tilt chair

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No, not the chair – what I mean is, I tilted this to get the chair in:

Dutch Angle, they call it. Hollywood term, mispronunciation of “Deutsch” – i.e. German.

As I have mentioned before, I tend to use angles for four different reasons:

  1. To add dramatic interest
  2. To add energy, dynamic motion.
  3. To make diagonals horizontal or vertical.
  4. To fit it all into the picture.

Don’t discount that last reason. People will assume I was being creative, but often I just want to fit it in. And -depending, of course, on the subject- that suits me fine. I once heard Peter Power, one of Canada’s premier photojournalists, say the same at a workshop I took. I agreed then, and I still agree!

And sometimes you til because you can’t stand up straight:

Just kidding. Really.

Curves

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Tip: always look for, and when you see them consider using, curves.

We like curves. While straight lines take us (and in the case of photos, our eyes) like a freeway to our destination, curves are more like a gentle river, or a winding mountain road, where it’s more about the trip than about getting there.

Imagine putting a bride on these stairs: wouldn’t that look good?

Backgrounds

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Another recent user question:

How do you determine the background you use for portraits?

That’s a tough one, because there is no one answer. What’s better? Look at these three “Autumn” and “Hollywood” series Honl gels:

Or this?

Or this?

Of course as usual, the answer is “it depends”.

  • For business, white is good, as is a very light blue.
  • For women, more elegant colours can be used (the purple above, for instance, is not usually considered a male colour).
  • Black is possible for dramatic low-key portraits.
  • Colours depend on hair colour, skin colour and suit colour.
  • You may, for instance, want to contrast with the suit.
  • You certainly want to contrast with the hair – avoid blending your subject into the background. (Or you use a hair light).
  • And sometimes, you may want to match the background to, say, a bright red suit, again in order to make the face stand out.

In general, the most important concerns I have are:

  1. It has to match the mood (conservative is blue, etc)
  2. Ideally, it go with the person’s clothing. That means either complementary colours (yellow and blue, say) or identical colours (A suit with purple in it? Then I can use purple in the background).
  3. Above all, I try to make the face stand out and avoid blending it into the background.

The basic rule: have fun, and keep it simple if you can. Try different colours but avoid very bright colours except for special effect. Have some very subtle blues and yellows and greens available just in case you want to add a splash of tint.

Tint is a good thing. Colour is more difficult!

I hope this gives those of you who use colour gels some ideas to try.

Focus-recompose-shoot?

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Reader Jeffrey recently read my post about focus points and commented to me. Because this is such an important issue – sharpness is essential – I thought it would be a great idea to reproduce his point here and to give my response below.

The distance to the plane of focus is the shortest in the center, longer
everywhere else. If you compose focus then recompose, you’re guaranteed to put the target in front of the plane of focus.

To test an exaggerated example, use your 16-35 2.8L at 16mm f/2.8, and
focus on something relatively close to the minimum-focus distance. Then
recompose with that something to the far edge of the frame, and shoot.
Inspect in Lightroom.

Unless unintended in/out movement of the camera during recomposure just happens to offset the change in distance to the focus target, you should find quite a difference… (and even if you don’t, do you really want to rely on a two-wrongs-make-it-lucky close-your-eyes-and-hope philosophy?).

Modern bodies have a bazillion focus points for a reason… so you can have one in the part of the frame you actually want to focus on, specifically so you can avoid the pitfalls of “Focus, Recompose, Shoot”.

Jeffrey is right that there is an issue. I understand the geometry (I am an engineer): when you recompose, the plane of focus as you move about your camera in a circular fashion around you is not a plane: it is a sphere. The sphere of focus means that seen from the subject you focused on, your focus points gets closer to you as you swing the camera.

But there’s a few moderating factors, and reasons focus-recompose-shoot often still makes sense:

  • There are only so many focus points. Specifically, few cameras have any around the “rule of thirds” points.
  • The centre one is more sensitive and is both-way sensitive.
  • Moving points takes a lot of time on many entry-level cameras.
  • It is only when you are close that this matters. Unless you’re close and at a large aperture, you will not see the difference.

That is why “focus-recompose-shoot” makes sense, or is often even necessary. But Jeffrey is right that it should be used with caution when close.

In fact when I use my cameras wide open at f/1.4, I hardly recompose, and when I do do it, I compensate by moving my camera ever so slightly before pressing the shutter. Works for me, but be careful and check your focus!

Reader Question

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Reader Craig asks:

Is it possible to get auto ISO to play nice with external flash (I’m using Nikon equipment)?  I haven’t played with it in a while, but I specifically stopped using auto ISO because I was finding it would give me ISO 800 based on the camera metering when the flash had plenty of power to push it to say ISO 200.  It seems odd to me that since there’s a preflash, that that information wouldn’t be shared with the camera to set the proper ISO automatically.  Just curious if that’s your experience as well or if there’s a way around it.  There are a a few scenarios where I’d be happy to use a (functional) auto ISO limited to ISO 800 and just deal with the noise reduction in post.

Good question. And as always… the answer is “it depends”.

First: if you take my “Advanced Flash for Pros” workshop, I go into all the nitty gritty details of both Nikon CLS/iTTL and Canon E-TTL. That will answer some.

But let me give a simple answer here. Typically when I am using flash, I will not use auto ISO. I prefer to keep things simple. Setting it myself means simple.

You expose the background using Aperture and ISO and Shutter Speed.  You make it look as dark as you like – say, two stops below ambient as a great starting point. Auto ISO means the camera will likely overrule your brightness/darkness settings. Manual exposure settings become a sort of “exposure priority” setting instead.

So while auto ISO can work well when using flash (just set expsoure two stops below ambient in S/Tv mode), it is not necessarily ideal when using flash:

  • In M mode, you cannot set exposure compensation
  • In S/Tv mode, you may get funny apertures
  • In Av mode, you may get slow exposures.

In fact on a modern Canon DSLR like my new 1D Mark IV, when using flash, ISO will automatically go off auto and will set itself to 400 when the flash is detected.

The preflash helps the camera set the flash power level for the foreground, lit-by-the-flash subject. The aperture, shutter speed and ISO settings set the background brightness. And again, typically I will be in manual exposure, and will set that to -2 stops, metered average (two stops below ambient). Auto ISO negates that!

So while it depends, it does not depend that much.  When using flash, I will usually set ISO to a manual. Yes, you can set limits to auto ISO (Nikon is much better than Canon at that!), but it is still better to do your own, and to keep control.

The above applies to indoors flash shots where the light is consistent enough for you to use manual exposure settings. Outdoors it would be different – except there is so much light you do not need auto ISO.