White Balance: Were it comes from, what it is and what to do about it

Things Digital Posted by Alun Foster Sun, February 27, 2022 22:19:19

By Alun Foster

Where it comes from

Objects in a scene reflect light (so we can see them) in a way that depends on their own surface colour and the colours in the illuminating light. Your eyes expect this to be “white” (though it often isn’t) and correct for this in “real life”: light must be a very strong colour before we stop seeing objects and start seeing art.

But our eyes don’t do a good job when looking at a photograph (which, of course, is always art). If the illuminating light source when the photograph was taken has stronger (or weaker) colours, this will affect the colours we see in the photograph, and this must sometimes be compensated for the photo to look “right”. The same is true if it is viewed as a print or on a screen of some sort.

Most natural sources of light have a colour that depends upon their temperature. In the ideal world of physics, they are “black body radiators” of light. (Paradoxically, an ideal radiator of light is also a very good absorber of light, hence ‘black’). Like this:

So, the colour of the light emitted is related to its temperature. We can say that light has a “colour temperature”, therefore. In reality, the only things to get that “blisteringly hot” are some very distant stars. Our own sun is quite a cool 5600 K, by comparison. This is why 5600 K (or close) is often used as the reference colour temperature.

I’ve made a table of some common light sources’ colour temperatures here, to get a feel for what this means in some scenes we can relate to.

Light Source	Colour Temperature
Candle	1000-2000 K
Tungsten Lamp	2500-3500 K
Morning / Evening sun (clear sky)	3000-4000 K
Fluorescent Lamps	4000-5000 K
Electronic Flash	5000-5500 K
Direct sunlight (noon)	5000-6500 K
Cloudy sky	6500-8000 K
Shade	9000-10000 K

A couple of things to note about this.

Colours that we associate with “warm” actually have a lower colour temperature than the blue tints we associate with things being cool.
Cloudy sky and shade show colour temperatures that are higher than that of the light source itself – our sun. The reason for this is the same as why the sky is blue. The air (and clouds) above us tend to reflect away the red tones, leaving the light looking more blue except when it comes at us head-on.

So, to correct for the colour of these light sources, to make them look as if they are close to our “standard “ 5600 K sunlight, we would need to “add some blue” (or take away some red) if they are too low, or “add some red” (or take away some blue) if they are too high on our colour temperature scale.

The effect of colour temperature (simulated)

In these photos, I’ve simulated the effect of various light sources on what we see in the scene.

Electronic flash is designed to be close to our natural view of ‘white’. Though it can look quite blue if used directly, diffused flash is probably your best bet for getting natural-looking colours when indoors.

A shaded area (or indoors near a window pointing away from the sun) is basically being illuminated by a huge blue light – the (hopefully blue) sky, so tends to look quite blue as a result. Giving your subjects a blue complexion is not recommended.

Incandescent (tungsten) light, on the other hand, is quite definitely orange coloured, which makes our photos look correspondingly so.

Gas discharge light of the “TL” variety actually emit a spectrum of light that is far from ideal (see later), but we often see the result as having quite a ‘green’ cast (so, we have to “add purple” to compensate for the missing red and blue). More on this type of light source later.

Adjusting for White Balance – in camera

So, what can we do about all this? Especially if you shoot JPEG (though, also useful to get a good reference if shooting raw), your camera will more than likely offer you a number of “White balance” options.

Auto White Balance (AWB). This is by far the best to use for all general-purpose shots. Here, the camera analyses the scene and tries to compensate for any colour cast. It generally works well, except at extremes (tungsten, shade) or when there is no “white” in the scene to guess from.

Presets. Like the name suggests, these are pre-cooked compensation for a variety of fairly standard lighting conditions (tungsten, fluorescent, flash, daylight, shade, cloudy). Simply select a WB preset as appropriate when taking the shot. (Pro tip – you can select the “wrong” white balance preset to get some creative effects. Try “shade” or “cloudy” on autumn colours, for example. Or “tungsten” during “blue hour” for some spooky effects).

Other Options. Many cameras will allow a “custom white balance” to be selected. This usually requires taking a photo of a white object (paper, …) in the prevailing light, which the camera will then use as a reference for adjusting the white balance of pictures taken with the “custom” mode. Some cameras may also offer a feature where you can “dial in” a desired white balance colour temperature (though this is often harder to use well).

Adjusting White Balance “in post”

All image editors will offer some means of correcting for white balance, and most work in more-or-less the same way. While post-processing corrections for WB can be done on JPEG captures, the range of correction you can achieve before weird things start to happen is more limited than when using raw. (See insert to get a technical background for this).

JPEG and raw JPEG format uses 8 digital bits per channel, whereas raw uses the full range of bits available from the sensor – usually 12, or these days commonly 14 bits per colour channel. This not only gives better precision in setting the level of each colour, it also gives more “overhead” for the arithmetic to work with before digital artefacts start appearing. Each extra bit effectively doubles the available range for adjustment, so going from 8 to 12 bits is already a 16-fold theoretical improvement. JPEG compresses the image data by throwing out a lot of colour detail (more than the luminance, or “B&W” part) – it is “lossy” compression. This lost information can be vital in colour-related corrections such as white-balance. Raw file formats use “lossless” (or sometimes, no-) compression, so all information for making colour-related adjustments is to hand.

In all cases, the first step is to call up a preset (most programmes have them). Like the presets in the camera, they use a standard set of adjustments for each of the commonly encountered modes. From these, small manual adjustments to “get it just right” are also possible.

In more difficult cases, you can usually use a ‘dropper’ to pick a “white” colour reference in the image. This could be a white shirt, or paper item in the shot, or even a colour reference card that you include in a test shot. Pro-tip: “white” objects could potentially be “blown out”, so is best to choose a neutral grey as a reference. White reference cards usually offer a white or a grey surface.

A more awkward “pro tip” when really desperate is to use the white of a person’s eye as a reference.

When in post-processing mode, you can also use local adjustments for mixed lighting cases (defined by masks or layers, … the terminology may be tool-dependent).

Other light sources

All of the above assumes a fairly “uniform”, ideal light source, like a “black body” radiator. Such sources have smooth, predictable curves that describe the wavelengths (colours) of light they emit. No gaps or major spikes. Nice and smooth, like that in this diagram.

Many man-made lights are far from this ideal.

Such lights are far from ideal for photographing subjects where the colour rendering is of any importance. Certain colours are over-represented, or even completely missing (an object of such a colour would appear very dark in the photo). The better-quality lights, especially of LED lamps, are carefully designed and measured to have a “Colour Rendering Index” (CRI), and this should be higher than 95 (or, even better, 98).

For most applications, understanding the light source in a scene and using white balance correction is quite good enough for most applications. For best colour rendering, use flash if you can, and/or a high quality continuous light source (CRI>>95). If all else fails and the colours don’t work for you at all (for example, when there is a mix of illuinating light, this can be very tricky indeed), there’s always conversion to Black and White…

If your particular application requires very good colour rendering, you can go the whole mile and use a colour calibration chart. Such charts allow a complete colour profile of the light source and the camera sensor to be built, to compensate all of these physical side-effects. This is in fact quite simple to do, and is covered in the next section.

The ultimate solution – custom ICC profiles

Colour management standards for digital imaging are established by the “International Color Consortium” – ICC. “ICC profiles” are essentially correction tables that can be applied to different parts of the flow of image information as it moves through the processing chain – coming in from camera sensor through your favourite image editor and going out to the computer screen or printer.

Manufacturers of the software and hardware we use provide profiles for “the best possible average” for their specific products. These standard profiles are certainly adequate or most applications (with the notable exception of monitor/screens, though some manufacturers do now offer calibrated screens – it’s still worth while checking this though). For applications that require better colour rendering, a custom ICC profile can be created for each lighting condition, and for each camera’s unique response to colour.

This may sound complicated, but manufacturers of such tools do make it rather simple to do. This article describes the use of X-Rite tools and Capture One Pro: other options are of course available, but all work in more-or-less the same manner. A brief step-by step guide follows.

Step One – Create a reference image using the calibration card.

Calibrating the light source and camera starts by taking a reference image using a calibration card. While a grey card can be used to detect non-optimal white balance, a more detailed reference for many different colours is needed to compensate in more demanding situations. The colours are not random: In addition to grey at different levels, they include skin-tone colours, a variety of “nature” colours and some prime references.

When taking the reference shot, it’s best to bracket the exposure to be sure you have one where none of colour channels are “burned out” (which would confuse the later calibration steps).

This example shows a calibration set up for a studio environment (recording a painting, using flash), but the same principle applies at an on-location shoot of any sort.

Step two – import the test image into your image processors

Due to the huge variety of raw image formats, colour calibration tools prefer to take in a standardised image format, such a TIFF or DNG. Therefore, use your favourite raw processor to create a TIFF or DNG image. (JPEG from a camera has already been processed and much of the colour information compressed, so is not directly suitable for this type of work). When converting the calibration image, it is important the no additional processing is done when creating the TIFF (or DNG) reference. This means:

Turning off any existing or default ICC profile. In Capture One Pro, this is done in the “Base Characteristics” tab.

Base Characteristics in normal use.

Settings required for the calibration image.

By selecting “No colour correction” and “Linear response”, the data from the camera sensor is in effect being imported complexly unmodified.
Colour correcting parameters in your editor must all be “neutral”. In particular, “White balance” control should be set to OFF or “None” if possible. The image can/should be cropped to include just the calibration card.

Step three – export the test image

Export the image as 16-bit TIFF (or DNG). For this, ensure that no profile or corrections are included with the file. A trick to do this in Capture One Pro is to “include camera profile”, which has in fact been set to “none” in step two above.

The output recipe format for Capture One Pro

You end up with a TIFF file that, unsurprisingly, looks like this:

Step four – create the ICC profile

The example here uses the software delivered with the X-Rite Colorchecker Passport. Start the programme and drop your newly created reference image into its window.

The programme will automatically detect the corner markers and place its monitoring points appropriately on each colour patch. It may need little help; you can manually adjust the corners to get the best match.

Test image in place within the Colorchecker software.

Simply clicking on “Create Profile” does just that. Give it a name of choice and it’s ready for use!

Step Five – using your new colour calibration profile

The newly created profile is used in place of the standard profile you may normally use in “Base Characteristics”, like this:

This profile can now be used when processing all images taken under the same conditions as the calibration shots.

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Pixels and Print sizes. Views from a distance.

When printing a digital image, it is important to know and understand how the size of the print, the viewing distance and the number of pixels in the digital image file interact to determine the perceived quality of the resulting print .

A standard reference is that the human eye can resolve about 300 dots per inch (or DPI – which is 118 dots per centimetre) on a 20×30 cm pages (A4-ish) viewed from a distance of 30 cms. Having more dots per inch than this is wasteful: you can’t see them: having fewer dots per inch and the image may start to appear “soft focus”. To assure quality, a little margin is taken – typically 330 or 360 DPI. For simplicity, like most people, I equate “dots per inch” to “pixels per inch”, though a printer will put down very many more dots in the space of each pixel due to the way they work.

If you do the sums, an A4-sized print needs a little over 10 million pixels to achieve 330 DPI resolution (which is roughly 3800 pixels on its longest side: 330 pixels per inch over 12 inches).

At this same resolution, a print at 40 x 60 cms needs 33 million pixels, and an A0-size (84 x 119 cms) needs 140 million pixels!

Hang on… Such huge files is getting to be a bit silly. Indeed, this observation was mentioned to me in a discussion with an artistic photographer who gets excellent, exhibition quality large prints with less than half the size of file this theory would indicate. Investigating further on the Interwebs I came across this useful little table.

Viewing Distance (m)	Resolution (DPI)
0,5	360
1	180
1,5	120
2	90
2,5	72
3	60
5	36
10	18
20	9

In other words, the further away from the print you stand, the lower the resolution needs to be for the same subjective quality. In fact, looking at the table you can see that the suggested DPI is simply 180 divided by the viewing distance in metres.

Elsewhere on the same Interwebs you can read that the best viewing distance is about 1.5 times the diagonal of the picture. Which makes sense, as you typically view larger things from further away. Put those together and you find that the DPI you need decreases as the print size increases, actually quite exactly, such that the number of pixels you need stays roughly the same, no matter how big a print you want to make!

Now, this is of course a theoretical case. Some people do go up close to exhibition prints to look at fine detail, so this guideline should definitely be regarded as the “minimum case”. In practice, a file with about 20 million pixels is quite big enough for the size of larger prints most of us need to make.

If the size of print you want to make seems to call for rather more megapixels than your camera gave you in the first place, it is tempting to use an image editor programme to “upscale” the number of pixels. Indeed, most do an excellent job of this. However, and this is again due to the way printers actually work (the difference between “dots per inch” and “pixels per inch”), my preference is to let the printer’s software do this upscaling: it will be better adapted to the exact requirements.

So, bottom line is – at least, if you fully trust the printing service – to get the best possible print, give the printer all of the pixels you have without upsizing.

(A complete table of paper sizes, required DPI and the resulting sizes is given here. Not for the NL, but for an article in “Resources).

Paper size name	Size (in.)	Size (mm)	Xcm	Ycm	Viewing Distance (m)	DPI	PxX	Pxy	Minimum MPx	Note
A10	1 ” x 1½”	37,125 x 52,5 mm	3,7125	5,25	0,10	600	876	1240	1,1	Size in inches is approximate
A9	1½” x 2 “	37,125 x 52,5 mm	3,7125	5,25	0,10	600	876	1240	1,1	Size in inches is approximate
A8	2 ” x 3 “	52,5 x 74,25 mm	5,25	7,425	0,14	600	1240	1753	2,2	Size in inches is approximate
A7	3 ” x 4¼”	74,25 x 105 mm	7,425	10,5	0,19	600	1753	2480	4,3	Size in inches is approximate
	3¼” x 4½	82,5 x 120 mm	8,25	12	0,22	600	1948	2834	5,5	Size in inches is approximate
3R	3½” x 5″	89 x 127 mm	8,9	12,7	0,23	600	2102	3000	6,3	Called “9 × 13 cm” worldwide.
4R	4″ x 6″	102 x 152 mm	10,2	15,2	0,27	600	2409	3590	8,6	Standard 135 film & print size in US, Canada, Australia and India. Called “10 × 15 cm” worldwide.
A6	4¼” x 6¾”	105 x 148,5 mm	10,5	14,85	0,27	600	2480	3507	8,7	Size in inches is approximate
4D	4½” x 6″	114 x 152 mm	11,4	15,2	0,29	600	2692	3590	9,7	New size for most consumer level digital cameras and Micro 4/3 cameras. Also known as “6D”.[3]
5R	5″ x 7″	127 x 178 mm	12,7	17,8	0,33	549	2743	3845	10,5	Twice the size of a 3R print. Called “13 × 18 cm” worldwide.
6R	6″ x 8″	152 x 203 mm	15,2	20,3	0,38	473	2831	3781	10,7	Twice the size of a 4R print. Called “15 x 20 cm” worldwide.
A5	6¾” x 8¼”	148,5 x 210 mm	14,85	21	0,39	467	2727	3857	10,5	Size in inches is approximate
8R	8″ x 10″	203 x 254 mm	20,3	25,4	0,49	369	2949	3690	10,9	Can be used for contact prints from 8×10 film. Called “20 × 25 cm” worldwide.
S8R	8″ x 12″	203 x 305 mm	20,3	30,5	0,55	328	2617	3932	10,3	Closest approximation to A4 (210×297mm), twice the size of a 6R print. Called “20 × 30 cm” worldwide.
A4	8¼” x 12¾”	210 x 297 mm	21	29,7	0,55	330	2727	3857	10,5	Size in inches is approximate
10R	10″ x 12″	254 x 305 mm	25,4	30,5	0,60	302	3023	3630	11,0
S10R	10″ x 15″	254 x 381 mm	25,4	38,1	0,69	262	2620	3930	10,3
11R	11″ x 14″	279 x 356 mm	27,9	35,6	0,68	265	2914	3718	10,8	Called “28 × 36 cm” worldwide.
12R	12″ x 15″	305 x 381 mm	30,5	38,1	0,73	246	2952	3688	10,9
S11R	11″ x 17″	279 x 431 mm	27,9	43,1	0,77	234	2567	3965	10,2
A3	12¾” x 17½”	297 x 420 mm	29,7	42	0,77	233	2727	3857	10,5	Size in inches is approximate
S12R	12″ x 18″	305 x 457 mm	30,5	45,7	0,82	218	2622	3929	10,3	“30 x 45”
“40 x 60”	16¾” x 24½”	400 x 600 mm	40	60	1,08	166	2620	3930	10,3	“40 x 60”
A2	17½” x 23½”	420 x 594 mm	42	59,4	1,09	165	2727	3857	10,5	Size in inches is approximate
A1	23½” x 33 “	594 x 840 mm	59,4	84	1,54	117	2727	3857	10,5	Size in inches is approximate
“60 x 90”	24½” x 35½”	600 x 900 mm	60	90	1,62	111	2620	3930	10,3	“60 x 90”
A0	33 ” x 47¾”	840 x 1188 mm	84	118,8	2,18	82	2727	3857	10,5	Size in inches is approximate

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My Kit

General Posted by Alun Foster Fri, July 23, 2021 00:41:44

(Someone providing feedback about the Viewfinders newsletter suggested members discussing their photography gear. Sounds like a good idea, so here we go.)

All My Kit (Smartphone photo)

My kit.

Before talking kit, let’s look at what I do, photographically. Next to being active in Viewfinders, I have a family that includes five grandchildren, so you can image there’s a lot of family photography in my life right now. Next to this, I have a day job in Communications, for which I do event shoots and some portraiture work, and this day job also allows me to continue (as a partial independent) a photography business I set up a long time ago as a means of supporting myself when I was suddenly laid off by my then employer. Mostly events photography, but some portratiture and increasingly, photos of artwork for catalogues etc… Because of the busy life (and covid), not a lot happens with that line right now, but when it does it is still important for me to be able to trust my kit. (As most working photographers know, you are only as good as your last gig so you gotta gettit right…).

That said, I am not really a kit geek. I have a set of reasonably good items that fit all but the most peculiar of tasks I need to do, be they for business or pleasure.

24-105mm f4 IS L

Bodies. As working camera, I have a Canon 5D Mk II. Already several years old, it is still proving to be as quick and as reliable as ever and (with 20 Mpx and some good optics) gives more than adequate quality for the type of work I do. It’s a very good all-round DSLR without many frills (which I wouldn’t use anyway), though is – like any DSLR – a little on the bulky side if you compare it with some recent mirrorless models. But as I said: most important is that it is fast and consistently reliable. I have a 7D kit as backup, too.

70-200mm f2.8 IS L

Optics. Most of the time (>95%), my kit is the 5D with Canon 24-105 mm f4 L IS (which works great on the 7D too). Beautifully sharp, and the slightly longer “reach” means I don’t need to change lenses so often. When I do, it’s most often for a Canon 70-20mm f2.8 L IS, though sometimes I do use a Tokina 19-35mm, or my recently acquired Canon 50mm f2.5 macro prime (I also have a 50mm f1.4 which is now redundant – any reasonable offer accepted). I often use a circular polariser, too (‘slim’ version for the wide angles, which fits all my main lenses).

50mm f2.5 macro

Lights. I have 2 Canon speedlights (plus one recently dead one – needs repair) and the special Canon ST-2 remote trigger, plus a very fun remote trigger/camera release kit from Hähnel (remember the squirrel?) One handy modifier I use quite a lot for portraits is a “beauty-dish”-like soft-box made by Roundflash, as well as some stands, umbrellas and backgrounds (inexpensive ones – these things have a tough life: my big background needs replacing). Oh, and two very cheap but remarkably good studio flash heads, which are small enough to be portable (useful for some of the jobs I do). I also have a tripod (Manfrotto), a remote release (cable and IR), and a monopod that I never use these days.

With this kit, I seldom find myself wanting for more. One item I would consider is a good, very wide-angle lens for full frame (like 10mm).

Tokina 19-35 mm

For processing I use Capture One Pro by Phase One. This is the real bee’s knees of raw image processors and the support for Canon is very good (I just can’t get on with Adobe software I’m afraid – it’s an engineer thing, don’t worry about it). I use X-Rite Color-checker Passport and Color-Munki for camera and monitor calibration/profiling.

Best accessory – Roundflash Dish: Worst buy: variable ND filter (it polarises, so shows strange dark areas, except on long lenses)

Et voilà – my kit, takes lovely photos and is good on the job too. Me happy…

Kit List

Cameras:

Canon 5D Mk-II, Canon 7D

Lenses:

Canon 70-200mm f2.8 IS L, Canon 24-105 mm f4 IS L, Canon 50mm f2.5 macro, Canon 50mm f1.4 Tokina 19-35mm

Canon EF-S 55-85 kit lens and Sigma 10-20mm (EF-S mount, for 7D)

Accessories:

Circular Polariser, UV filter, Variable ND filter

Canon cable release + IR

X-rite Colorchecker Passport

Tripod (Manfrotto)

Lights:

Canon 430 EX + 580 EX-II speedlights

QS-DGS150 flash heads

Mini Manfrotto LED light

Canon ST-2 remote trigger, Hähnel “Captur Pro” remote flash/camera trigger kit

Light Accessories:

Foldable Backdrop

Roundflash “dish” speedlight diffuser

Reflector (5 colours including black)

Umbrellas (Several)

Flash stands (3 in total)

Various GOBOs / modifiers

Post Processing: Capture One Pro, with (BenQ) monitor calibration using X-Rite Pantone Color-Munki and Color-Checker Passport

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Colour management from front to back.

Things Digital Posted by Alun Foster Thu, July 22, 2021 23:54:24

Well, the front part today at least. Regarding the “digital” parts of photography, many articles have already covered the importance of checking that your computer output device (monitor, and eventually printer) are properly calibrated/profiled etc…, so that the colours represented “in the digital domain” (i.e. as numbers in your computer) come out looking like we’d expect them to. Up to now, not so much attention has been paid to what happens before we get into the “digital domain” in the first place – i.e. how the camera we use perceives colours, and also how the lighting we have may be affecting the way it “sees” the colours.

There are basically two things that can affect the way a camera will record the colours in a scene:

The light illuminating the scene. For most sources, its “colour temperature” – though other sources like LEDs and low-energy lights have special characteristics too. (These can be weird: they emit light with very irregular spectra, with some colours missing altogether so they could appear as black in your picture!) In general, your camera flash is the best bet where practical, but if you must use continuous lighting, lamps (including LEDs) have a “Colour Rendering Index” (CRI) which must be above 90, preferably 95, if you need to render colours correctly.
The camera sensor. Here, problems could be caused by a variety things, but the combined effect of these is that the cameras sensor is a good, but not perfect, converter of light to digits.

Both sources of colour variation can be addressed in one go, by using a colour calibration chart. By photographing this chart alongside the subject of your picture, a “profile” can be built that can be used to cancel out pretty well all of the affects mentioned above.

Looking into what is available, it became apparent that, while support for Adobe products seemed fairly prevalent, other platforms such a Capture One (my photo processor of choice) seemed less well served. X-Rite Pantone® seemed to be the only reputable source of the necessary tools (my ColorMunki Photo monitor calibrator comes from there too). On the basis of this I purchased an X-Rite “ColorChecker passport”, and downloaded its accompanying software.

The colour temperature of the light can, to a great extent, be compensated by selecting the appropriate “white balance” setting, either when you capture the image or in post processing. (If using JPEG, you really must do this when shooting). The camera’s default “profile” can also be used of course, but is this precise enough?

To be honest, for the vast majority of pictures, the answer is yes. But for the specific application I have (reproducing paintings etc…), it may not be ideal. Thankfully, companies the likes of X-Rite, Adobe and Phase One make it very easy to set up the necessary “camera profile” that provides compensation for all these non-ideal phenomena (at least when using raw format), by including the colourful patches in a test shot or two, using RAW format. Process the test shots, assuring that the default profile is turned off (in Capture One Pro, this is under “Base Characteristics” – see the screen grabs: they are similar in Lightroom) and setting the response curve to “linear”, we then need to isolate the colour checker by cropping to it, to make an image suitable for the X-Rite software to analyse.

Select these for camera calibration

Having done that, we then need to export an image that the X-Rite programme can read. This must be 16-bit TIFF, and not be influenced by any output profile. (For Adobe users, a DNG file can be used instead of TIFF). So, we select “embed camera profile”, which through the above step is now set to be fully neutral.

Output process

We can then simply “drag and drop” the resulting TIFF image into the X-Rite programme, tweak the automatically detected reference points and let it do its magic. Give the resulting profile a name to remember, selecting “ICC” for Capture One Pro or “DNG” for Adobe, and save it.

Back in Capture One (or Lr / Ps), select the camera ICC profile just created (and select “auto” Curve) in the “Base Characteristics”

and you’re ready to roll with a very nicely calibrated front end!

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Serendipity rules

General Posted by Alun Foster Sun, May 02, 2021 15:45:34

An interesting concept popped out of a recent conversation with an artist friend.(Well, I thought it was interesting…). I was admiring the creativity of the underlying concepts in their work, explaining that – as a photographer – I regard myself as something of a ‘functionalist’ (at least, as far as my little business goes): I make photos that people need, mostly for purely practical reasons (and, increasingly these days, making pictures of others’ artistic creations). I set up my kit, adjust the lights, make some necessary steps to be able to calibrate the outcome later and click…

“Oh, that’s very technical” they said. Which made me think – well, isn’t the knowledge of how your paints and colours combine and flow, how they cast their shadows on the canvas; how the clay and plaster forebears of your bronze sculptures bend to your will, expressing that inner purpose and beauty in a way I could never imitate; is that also not “technical”?

I am starting to wonder now if there is indeed such a clear polarisation between the “technical” and “creative” aspects of any art. It is so that technical parts, once mastered, become second nature and we tend to no longer think about them: we concentrate on what we somehow feel in our mind’s eye when constructing the [insert name of artefact in question here: e.g. photograph] . We are in that sense “being creative”.

But if we never question the technical part, won’t the output of our endeavours somehow converge to being the same after a while? Is it not a good idea to try out different technical approaches to see the result?

Experimentation costs nothing, but it does challenge the imagination, and from this can come some new, really great art.

In the creatively technical land of technical creativity, serendipity rules …

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Time marches on …

General Posted by Alun Foster Wed, March 03, 2021 20:20:17

It’s March already. Spring is upon us, and with it come many more opportunities than we have had of late, to wander out into the wilds of [insert town/city of residence here] to capture another new phase of the world around us. The weather has certainly been very spring-like lately, adding to the joy. But it’s all too easy, I find, to lose track of what we want to achieve with photography when randomly shooting while out and about. A project to focus on is a useful tool, but it’s not always easy to come up with something concrete.

Our Viewfinders projects can provide inspiration, and – I discovered – so can acquiring a new piece of kit. Buying new kit is something I rarely do, and I realised this when I recently purchased a second-hand lens. A macro lens – the first one I have owned (would you believe?), which is a step way beyond the makeshift (i.e. not very portable) solutions of self-made extension tubes or reversing rings I’d used in the past. And getting in close to a subject can reveal a veritable playground of possibilities. Highly recommended! (As are our Viewfinders projects, by the way… 😊 ).

Here’s a collection of pictures taken with that newly bought lens – a walk around sunny Brussels…

I’m – er – keeping the up-close pictures for a Viewfinders project… You’ll get to see them some other time 😉

Comments(0) https://blog.dafos.be/?p=348

Three-legged race

General Posted by Alun Foster Wed, October 28, 2020 23:02:01

Someone in the Viewfinders photo club asked an interesting question. What to look out for when buying a tripod?

Maybe not the most high-tech of questions, but interesting none the less!

I don’t know the particular brand of tripod they were looking at, but my experience covers things to look out for which are not really brand-specific. Here’s my list, in no particular order.

For the record, I use Manfrotto with quick-removable plate.

– Is it TALL enough? What is the maximum height you can get out of it with the legs still being reasonably stable? Sounds odd, but all my first tripods were too short – I had to stoop to use them, which gets tiresome after a while. One with a central pole that can raise up quite high is surprisingly useful. I also use the tripod as a flash stand for special effects, so it sometimes needs to be quite high.

– Rigidity/stiffness. THE most important. Mine is aluminium tubing and is really very rigid. I have seen some good quality carbon fibre ones of comparable stiffness, but also some cheaper ones which flex far too easily. Definitely a false economy.

– A model with some soft wrapping near the top, where you might want to hold onto it (mine doesn’t have this, and I miss it). This has no photographic function, but if you’re outside in the cold, without gloves (so you can feel what you’re doing), the tripod can be VERY cold to the touch, and these soft wraps make it more manageable.

– Flexibility to do alternative configurations. Standing straight up, they’re all OK, but ones where the legs can be independently splayed much wider, for example, and where the central column can be mounted “upside down” and/or placed fully horizontally are very useful. Use for macro shots close to the ground, document copying (horizontal), positioned on uneven surfaces or on stairs, … you name it, this is probably the most useful.

– Fast release plate, of course. And I find the butterfly screw tightening used on the legs of my (already quite old) model fiddly but they have one big advantage: they don’t go “CLICK!!!” in that quiet church when photographing weddings. (No Velcro on the camera bag for the same reason).

– Light weight is good, but if it compromises on any of the above, it would detract too much from its functionality for me. I borrow a cheaper portable one for more touristic applications.

– Some models have a hook at the bottom of the vertical column, on which you can hang a heavy bag. Good for stability in windy conditions.

– The head. Mine came with 3 locking levers, for “roll/pitch/yaw”. I actually left only the pitch in place, and pre-tightened the other screws to be able to move them by hand, yet still tight enough hold their position. I find this most useful in practice. (Heads designed for video applications don’t work too well I have found, but that’s maybe just me).

– Can you put the plate on backwards? I sometimes do this to allow me to point the camera to very high elevations (star photos).

– Can you use it as a monopod too? I have used mine with just one leg extended for extra stability in difficult lighting when doing events (where you need to be agile).

Oh, and a spare plate. One on the camera, of course, but also one on the tripod mounting plate of my pretty hefty 70-200 f2.8 zoom. Really useful, that!

Comments(0) https://blog.dafos.be/?p=337

Turn turn turn…

Things Digital Posted by Alun Foster Sun, August 23, 2020 15:50:02

Not about photography this time, but another web programming exercise. I wanted to make a “spinner” to keep people busy while the new photo carrousel I put in the into section of my website was loading.

As my site is already quite “clunky (*)” I thought to try something using only the built-in features of HTML and CSS (no javascript for this one).

It’s quite hypnotic, and I’m rather proud of it, actually!

(* I’m not a professional web programmer and learned my computer programming skills during my career as a product marketing engineer for microprocessors, and while building this site over the last 8 years or so. Some of the original code I wrote early on is not so easy to maintain, therefore. When I changed jobs a long time ago, I promised myself to not go and learn another programming language – I broke my promise… 🙂 )

<!DOCTYPE html>
<html>
<title></title>
<head>

<style>
.container {
border: black solid 1px;
padding: 20px;
background-color: grey;
height: 500px;
}

.spincontainer {
padding: 10px;
text-align: center;
background-color: lightgrey;
}

.spinpaper {
display: inline-block;
position: relative;
box-sizing: border-box;
text-align: center;
width: 250px; height: 250px;
background-color: rgba(255,255,255,1);
border-radius: 100%;
}

.spintext::after {
width: 100%;
position: absolute;
top: 50%; left: 0;
margin-top: -11%;
text-align: center;
font-size: 2.2rem;
content: "\00231B";
}

.turning1, .turning2, .turning3
{
display: inline-block;
position: absolute;
box-sizing: border-box;
margin: auto;
width: inherit; max-width: 90%;
height: inherit; max-height: 90%;
top: 0; bottom: 0; left: 0; right: 0; /* Force centering by pulling on all four corners */
border-radius: 100%;
}

.turning1 {
border-top:    20px solid rgba(0,0,127,1);
border-right:  20px solid rgba(0,0,127,1);
border-bottom: 20px double rgba(0,0,127,0);
border-left:   20px double rgba(0,0,127,0.5);
animation: turner linear 3s infinite normal;
}
.turning2 {
border-top:    20px solid rgba(127,0,0,1);
border-right:  20px solid rgba(127,0,0,1);
border-bottom: 20px double rgba(127,0,0,0.5);
border-left:   20px double rgba(127,0,0,0);
animation: turner linear 1.8s infinite reverse;
}
.turning3 {
border-top:    20px solid rgba(0,127,0,1);
border-right:  20px solid rgba(0,127,0,1);
border-bottom: 20px double rgba(0,127,0,0);
border-left:   20px double rgba(0,127,0,0.5);
animation: turner linear 1.2s infinite normal;
}

@keyframes turner{
from {transform:rotate(0)}
to {transform:rotate(360deg)}
}
</style>
</head>

<body>
<div class="container" id="background" >
 <div class="spincontainer">
  <div class="spinpaper" id="spinner">
     <div class="spintext"></div>
     <div class="turning1"><div class="turning2"><div class="turning3" ></div></div></div>
  </div>
 </div> 
</div>
</body>

</html>

Comments(0) https://blog.dafos.be/?p=328

Flash (indirect)	Window (blue sky)
Incandescent lamp (tungsten)	Fluorescent light (“TL”)

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