Sunday 19 December 2010

Olympus 24mm f/2: Stay Frosty


5D MkII / Olympus 24mm f/2 @ f/2

A while back I wrote about the Olympus 24mm f/2.8, a vintage lens for the Olympus OM system of the late twentieth century. Olympus stopped production of the OM range several years ago, but the lenses are still readily available on the used market, and some of them are pretty good. They can be easily adapted to work with modern Canon digital SLRs with a simple metal adapter ring, and unlike some of the old Pentax Takumars they don't have clearance problems with the mirror on a 5D.

The 24mm f/2.8 is particularly handy if you have a 5D, because Canon doesn't sell a good cheap wide angle prime. In fact the company's wide angle range has always been weak; either cheap and nasty, or very expensive and disappointingly okay. The 24mm f/2.8 is nice and sharp and used examples sell for less than £100. It's tiny, too. Tinier than Holly Hunter, who is 5'2". Tinier than Dame Judi Dench, who is 5'09". Tinier even than Christina Ricci, who barely tops five feet. Here's an alpaca:

I call him McCartney McAlpaca or Macca the Alpaca for short. And he is short; shorter than a llama, which is one of the things that differentiate alpacas and llamas. Alpacas are half the size of llamas. They are shorter than Christina Ricci even, but weigh more than her. This is in contrast to Christina Hendricks, who weighs more than an alpaca but less than a llama. She is taller than an alpaca and almost exactly the same height as a llama. And she has humps, like a camel.

EDIT: A correspondent points out that there appear to be two alpacas rather than just one. This is in fact an illusion; the second alpaca is actually a temporal echo of the first. Alpacas are descended from a race of beings that existed before the physical properties of the universe had become solidified, and are not governed by the laws of time. Thus the second alpaca is actually the first alpaca, but at a different point in the space/time continuum, apparently some time in the past. Alpacas leave a trail of temporal echoes that extend to infinity, but only the first echo is visible; the others have been redshifted by the acceleration of the universe into invisibility, although you can still touch them. It is entirely possible that the alpacas are preceded by an infinite string of blueshifted future alpacas which time is rushing to meet, and that they are the rails upon which time runs, and perhaps they link at some point with the redshifted alpacas to form a giant ring. Like a tiger devouring its own tail.

Still, back on topic. As far as I know it's tricky to mount old OM lenses on other SLR systems. The registration distance is too long for Pentax and Sony / Minolta, and not comfortably long enough for Nikon, although the difference is small enough that the lenses can be modified to work (a company called Leitax will sell you the parts). For the Micro Four Thirds system Olympus will sell you an official adapter, although the 2x crop factor and tiny high-resolution sensor means that the 24mm f/2.8, for example, becomes a mediocre slow 50mm. Then again, if you want a nice sharp 400mm f/4 for a fraction the price of Canon's 400 f/5.6L, there you go. Manual focus, mind.

5D MkII / Olympus 24mm f/2 @ f/2

I think the sculptor started out making a man, and added the breasts later on. Still, the 24mm f/2.8 wasn't Olympus' only 24mm lens. The company tended to make several versions of each focal length, differentiated by lens speed; typically there was a fast, expensive f/2 version and a slower, cheaper f/3.5 budget option and a middle-of-the-road f/2.8. For the 24mm focal length Olympus did things a little bit differently. There were actually two f/2.8s, the manual focus version mentioned above and an autofocus version that came out in 1986, which appears to have had the same optical design. It may well have been just as good, but unfortunately due to some short-sighted thinking by Olympus it was autofocus only, with no manual focus or manual aperture rings. Unless Novoflex ever release an OM-707 - EOS adapter ring it is useless nowadays.

The f/3.5 version, meanwhile, was a stunningly expensive shift lens that sells for nigh-on £1,000 on eBay. Is it any good? I have no idea. You're welcome to buy one and send it to me (seriously - I won't break it) but then again how can you be sure that this blog wasn't started all those years ago for the sole purpose of swindling you out of your Olympus 24mm f/3.5 shift? You can't.

5D... and so forth. They're all at f/2.

Dah dah dah and there was a fast 24mm, the 24mm f/2. One stop faster than the f/2.8. It's not all that expensive on eBay. Here it is, next to the f/2.8:

It's relatively massive for an Olympus lens, with a huge 55mm filter thread. It weighs several grams! Mine is presumably multi-coated (it has MC written on it) and has a date code of G18, which means that it was made in August 1981, according to John Hermanson, who is the most useful man on Photo.net. If that one post of the 578 he has posted is the only one of worth, his ratio of useful posts to useless dross is still higher than most of the people on Photo.net.

How much did it cost in 1981? Again, I have no idea. Back in futuristic black-clad 1985 it sold for $203 in the US, according to this B&H price list, which is hosted by a man called Nesster, who has a tonne of fascinating old magazine ads and things. The same page also lists the old, FD version of the Canon 24mm f/1.4 L, which was $584. Why $584? Why not $599? You'd think, being American, the people of B&H would not be wonky with money.

Nikon and Canon also made 24mm f/2 lenses, and so did plucky little Pentax! The dears. None of them seem to have captured anybody's imagination, certainly not compared to the Nikon 28mm f/2.0 or the Canon 24mm f/1.4 or the Zeiss 20mm Flektogon etc etc. Perhaps the spec fell between too many stools; 24mm isn't super-wide and f/2 isn't super-fast. Even on a full-frame body you need to put the subject right up close to the camera to get narrow depth-of-field effects, and if you're using a modern digital SLR and the light is getting low you can just turn up the ISO value. Nowadays if you want a fast 24mm you have a choice between Nikon and Canon's 24mm f/1.4, which are exotic and expensive, and that's about it. If you want a fast prime with a 24mm focal length for an APS-C digital SLR you're out of luck, because there aren't any. Yet. Is there a market for an APS-C 16mm f/1.4? Sigma, are you listening?

But anyway, let's have a look at the Olympus 24mm f/2. What's it like? How does it compare with the 24mm f/2.8? And will Heironymus Merkin ever forget Mercy Humppe and find true happiness?

Here's what the vignetting looks like at f/2, shot on a 5D MkII with live view:

Here's the middle at f/2. A 100% crop uncorrected for anything, but with mild unsharp mask of 0, 0.5, 150. It's generally sharp but has a kind of purple glow which, to be fair, wouldn't be so visible if there was less snow:

Here's part of the right edge, just outside the APS-C zone:

On an APS-C camera, such as a 60D, it would be a kind of 38mm f/3 t/2 e.g. it would transmit as much light as an f/2 lens but with the apparent depth of field of something like an f/3 lens in full-frame terms. And here's the bottom-right corner, which is softer. Serves you right for shooting a landscape at f/2:

Before we go on, here's something else. This was also shot at f/2 and illustrates something called coma, which goes away when you stop down. At f/2 it distorts point light sources and creates an odd swirly effect:

Here's a phone box. The exact same box appears at the bottom of this post, but in daylight and a day later, after England was destroyed by snow:

Let's introduce the 24mm f/2.8. Here's the middle at f/2.8 - one stop down for the f/2 - with the f/2 at the top and the f/2.8 at the bottom:

I was curious to see if the 24mm f/2 was better than the 24mm f/2.8 at f/2.8, and by gum it appears to be so. Not by much, but it's there; more contrast, less glow, a bit sharper.

Here's the just-past APS-C edge at f/2.8, f/2 at the top. They look pretty much the same:

And here's the corner. "Master Ninja Theme Song!":

That'll also teach you to shoot landscapes at f/2.8. The 24mm f/2.8 actually looks a bit better in the extreme corner. How about f/11? Eh? How about it?

I'm fairly sure the f/2 is at the top. If I layer one image on top of the other and then switch between them I can't see any difference that can't be explained by minor variations of exposure and colour temperature. The Canon body, left to its own devices, shot slightly blue through the f/2, slightly green through the f/2.8. Here's the edge, and notice the CA:

The difference is striking...ly absent. Here's the corner:

The f/2 is just slightly better to my eye. Just slightly fuzzy in the last few pixels. As before these are 100% crops from a 21mp full-frame image.

I was curious to see how it would be with video, so here are some shots at f/2 with some music by myself layered over the top:


The music is basically the same tune as the second half of this, but faster, and the bass seems to have survived Youtube's uploading process. I arranged it with Audiomulch, and made the robot voice-type effect by feeding the drums and the bassline into a vocoder. In retrospect I needed a graduated neutral density filter to dim the sky a bit. f/2 is handy for low-light, but as mentioned earlier it's hard to get sweet depth-of-field effects at 24mm. So, if you're shooting video, it's not much more useful than any other 24mm prime, or indeed a 24mm zoom, albeit that the 24mm f/2 will probably have less distortion, which is harder to correct with video (if only because a lot of editors don't have distortion correction options; Virtualdub will do it, but it's not a simple click-and-drag operation).

Internet legend has it that the f/2 suffers from a kind of hard-to-correct moustache waveform distortion, but it doesn't really leap out at me. It exists, though, as in the following photograph taken at Sidi Bou Said in Tunisia that has the horizon along the top:

At the top f/2, illustrating the vignetting, below it f/8. At this distance essentially everything is in focus at f/2; I would have needed to get real close to the post to blur out the background. Why didn't I? Can't remember. From top to bottom it says BOCH 8Y, RANOU, ANGFAROUHAI, CHACHA, CHACHO, ZIZOU, HOS, S, A.

Still, and in conclusion, the Olympus 24mm f/2 is sweet. Stopped down it's extremely good; at f/2 it's not fantastic, but at least you have f/2. And despite being larger than most Olympus wide angle primes it's still relatively compact. Here's that phone box again:

All of the flavour shots in this post were taken at f/2; the vignetting actually helps this image because it makes the phone box stand out. Here's a 100% crop of the middle to illustrate what f/2 in the middle looks like in a real-world shot:

Here's some flare, shot at ISO 3200. The flare isn't the white blob to the left - that's the moon, suffering from the coma I mentioned previously - it's the patch just right of centre:

And this is the end of the post. Scroll down a bit for almost exactly the same shot, but in infrared! With a 10D struggling at 1600.

Thursday 2 December 2010

Infrared Y: Swirly-swirl went the snow

It doesn't usually snow in the south of England in November, but we live in interesting times, and so I decided to take my infrared camera out into the swirling snow and take some pictures. I was curious to see what snow looks like in infrared. See, you'd instinctively expect it to look black when photographed with a thermal imager, because it's cold, but on the other hand my camera isn't a thermal imager, it only records near infrared, which is a different kind of cider altogether. Less gassy, with no strong aftertaste. Ahh, Leslie Neilsen. All things must pass. All things must pass away.

Ahh, George Harrison. Sorry, I'm drifting from the topic. Like a snow drift! Drifting. Snow. But does snow look black through a thermal imager anyway? My child-like curiosity led me to this discussion thread about the computer game Modern Warfare, which is a game that has some levels set in the snow, and you have a thermal imager. The game apparent renders snow as white when seen through the thermal imager, whereas in real life it would be grey, according to some young men who play Modern Warfare. And this video on YouTube, which has a man loitering around near some cars in the snowy darkness.

As you can see, my camera records snow as snow, presumably because the snow is reflecting near infrared radiation from the sun (which is in turn being filtered through the clouds; it was a cloudy day).

The shop in the picture is a butcher, Harrison Bros. This butcher, in fact. Shining out in the snow like a beacon of meat.

Have you ever eaten a whole bag of mints? You start by putting individual mints into your mouth, sucking them slowly until they melt, and then eventually the lust consumes you, overwhelms your fear, and you start to chew the mints instead of sucking them, and then you put several mints into your mouth, in a kind of mint orgy, and then the mints are all gone.

Don't feel sorry for the mints. Somewhere in the universe there is a planet where mints are the ruling species, and they use human beings as snack food. They pay for the food with little bits of tin foil. The mints have evolved over time into different breeds. Some are round with a hole in the middle - they are the female mints - some are semi-transparent, like an ice cube, very masculine, and some are coated with chocolate; these mints were once enslaved by the other mints until they won their freedom. Nonetheless they are still excluded from high-paying jobs and are forced by economic necessity to live in poor-quality housing. The mints worship a giant tongue who is simultaneously their god and their devil. They brush their teeth with meat-flavoured toothpaste. Such is life on the planet of mints.

They have a space programme. They plan to send a probe to their moon, which in their mythology is made out green chalk (of course). Because chalk is the opposite of cheese.

I bet you're wondering where "swirly-swirl went the snow" came from. This. Page 86 of the March 1988 issue of Sinclair User. Preview of Yeti, a clone of Exolon, which was a game where you were a little man that waddled slowly across the screen, and you had a gun and - this was the thing - a rocket launcher in your backpack. When you launched the rockets they went WHOOSH! up into the air, leaving a colourful trail behind them.

In hindsight the game was slow, boring, the gameplay was a throwback to a bygone age. Gunrunner, from the previous year, published by the same company, was conceptually similar but more sophisticated. But Exolon was more colourful and it had the rocket launcher, and so it was a big hit and spawned a load of clones. Raffaele Cecco had a yen for polishing up obsolete gameplay concepts with slick programming and production. Cybernoid was essentially Underwurlde or Starquake or any number of 1984, 1985-era games, but with a little spaceship, and just like them it was unfairly hard and no fun at all to play. But it had colourful explosions and a fantastic soundtrack (overshadowed by the C64 theme for Cybernoid II, though) and it sold loads.

I just had to get that off my chest. Twenty-two years of silence. No more.

Sunday 28 November 2010

Infrared X: Red Army Calls You

I've filled up the last few posts with some infrared photographs, of people and places, wavelengths redder than red. The process that created these images is long and complicated and now I shall try to explain how I did it. But not why. I can't explain why.

When Ansel Adams decided to set down his sorcerer's ways in book form, he came up with THE CAMERA, THE NEGATIVE, and THE PRINT, three weighty books that are still fetishised by sad disciples of the ancient religion of film photography. I grew up in Britain in the 1980s and so my natural instinct is to destroy the past; smash the four olds, but nonetheless Adams' compartmentalisation of the photographic process seems sensible, despite the fact that he was the product of the great Satan. First there is the camera; then there is the exposure; and then there is the electronic wizardry that turns a muddy-looking red smear into a visual symphony of angles and contrasts. I will not bother with THE PRINT because that kind of thing is old-hat, pre-internet. We have moved beyond physical media. This post is about THE CAMERA, the input device. The combination of camera and lens. The next post will be about THE NEGATIVE, the digital file.

Painters have their brushes, photographers also have their machines. Some people fetishise the technology and never move beyond. These are the people who buy coffee table books filled with photographs of guitars, the kind of people who write lengthy blog posts about the smallest technical details of old cameras. Boring empty people, the kind who write at length about (for example) infrared photography. They are wasting their lives, and yours. Here's a bloody rainbow:

The CAMERA
Let's suppose that you want to take hand-held infrared exposures. You don't want to put the camera on a tripod and wait for five seconds per exposure, you want to hold the camera in your hand and shoot whatever the bloody hell crosses your path. You're impatient, easily bored, you grew up in Britain in the 1980s and you hate the past and slow things. You worship speed and are naturally suspicious of depth. You hate waiting. Smash and hate.

In earlier posts I stuck a visible light blocking filter onto a conventional colour digital camera, with surprisingly good results, but that only worked because the camera I used was unusually sensitive to infrared, being old. A rare example of an old thing still being useful today, along with e.g. the Browning Hi-Power pistol and the Boeing B-52 bomber. Modern cameras tend to be much less sensitive to IR; my 5D Mk II has such a strong infrared blocking filter that I have to take thirty-second exposures at ISO 1600 in bright sunlight to get a signal. A tedious process. If God - who does not exist - had intended me to stand still for thirty seconds he would have broken my legs.

Or he would have made me without legs. And even then I would still move around. Like that athlete, you know. Aimee Mullins, who was in Cremaster III. She was born without fibula bones and so they took her legs off when she was young; then she became a sprinter, a job that involves moving around a lot whenever a gun goes off. Imagine if they dropped her into the Afghanistan war, with all those guns going off; she'd never stop running. Which would be perfectly sensible given that it's the Afghanistan war. She'd probably survive better than people who just stood still. I must take less cocaine. Fewer cocaine. I must take less of it.

There exist a very few dedicated infrared cameras, such as the Fuji IS Pro, but these tend to be very expensive and aimed at nerds and sad technical boffins. The next option, and one of the most popular, is to take a cheap old camera and send it off to the appropriate company to be converted into an infrared camera. The conversion process involves taking off the infrared blocking filter and replacing it with a visible light blocking filter. The camera still functions as it did before, but instead of recording visible light it records infrared.

But which camera? If money is no object there's nothing to stop you from buying a Nikon D700 or Canon 7D etc and converting that, but as I have always said, if money is no object, why the hell are you bothering with cameras? Live your life of ease, don't waste time photographing it.

The absolute cheapest digital SLR on the used market in Britain as I write these words is the Canon D30, which is a three megapixel model from yonks ago. Three megapixels does not excite me; but for a tiny bit more money you cold have a Canon D60, which is a six megapixel model that people tend to confuse with the more recent 60D. However the D60 only goes up to ISO 1000, which is limiting. One step up again, £130 or so, gets you a used 10D, which seems to be a technological sweet spot, and a popular choice for this sort of thing. It's not really good enough that you'd miss throwing away its ability to take pictures with visible light, and it's not so old and noisy and slow that it's a waste of money. Here's mine, with the battery grip and a Samyang 14mm f/2.8:

I have taped over the 10D logo with gaffer tape so that people will think it's a posher camera because I hate the blinking self-timer light. Just for the hell of it, here's a portrait of my 5D MkII taken with the 10D:

The lens is an old Olympus 21mm f/3.5. It's made of metal, painted black, and so is the camera, but it must be a different kind of paint. Altogether. "I'm the locksmith. And... I'm the locksmith."

While I'm photographing cameras, here's my Olympus OM-10:

The colour makes it look like a rare special edition, like one of those gold Leicas, of which there have been many down the years. There was never a gold Olympus 24mm f/2.8, although there was a gold OM-2N. Because I'm on a roll, here's some fruit:

I also photographed a cup of tea, but I'm not going to post the image because it looked like a mug of warm semen. It really did. I'm not just saying that to be shocking; it really did look like a mug of warm semen. I drank it just the same.

The Canon 10D
The 10D was a kind of slicked-up refinement of the D60, with a tougher all-metal body and ISO 3200. It uses cheap and widely-available BP-511 batteries and takes ordinary Compact Flash cards, although it has trouble with cards larger than 2gb. The most recent firmware will read larger cards, but I have had trouble with the camera locking up when a 4gb card is almost filled up, so I use a couple of good fast 2gb cards instead. 2gb equals roughly 240 RAW shots, and you will be shooting RAW. Dunno why I write RAW in capitals, it's not an acronym. It's not even a file extension (the 10D produces .CRW files, which it batches into hundred-file folders, which are a bugger to archive).

NB Companies other than Canon have made digital SLRs, and some continue to do so. But Canon made a lot of them, and thus they tend to be slightly cheaper on the used market. The direct parallel universe Nikon-world analogue of the 10D would be the Nikon D100, which from what I have read is just as good and bad as the 10D (good image quality, slow). Nikon also made a string of six-megapixel SLRs with slightly cheaper bodies - the D70 and D50 and D40 in that order - which are apparently just as handy. Fuji's S2 is also available cheaply, but according to Lifepixel - more about them later - they cannot be converted into infrared cameras. I owned one for a short while; it was sensitive enough to infrared that it would record a signal with two, three-second exposures, but not shorter than that.

The battery grip is fairly cheap, and you can use it with the D30 and D60, if you have one. A rare example of Canon maintaining backwards compatibility with its accessories. On a physical level my example is well-used but still feels like a single block of metal. The one major physical limitation is that it can't mount EF-S lenses. It predated the EF-S standard by a few months and the lens mount simply won't accept them. This is one of the reasons why the 10D is so cheap; you're restricted to Canon's full-frame lens range or digital-only lenses by Sigma and Tamron and so forth. The 20D didn't have this problem and this is one of the reasons why it's about £200 on the used market, a substantial step up from the 10D.

There is another thing. The 10D is very slow. Slow to start up, slow to write images to the card, slow to play them back. If you're taking intermittent landscape shots you'll never overwhelm the buffer. If however you're taking fashion-style portraits you'll quickly find yourself mentally swearing as the camera says BUSY at you. It takes ages to clear the images to the card - less than a minute, according to DPReview, but it feels like forever - and until it does you can't review the most recent shot. If God had intended for me to stand there for a minute watching a bar slowly count down to zero he would have made me a deep sea diver. In this respect the older Kodak DCS 560 was much better; it had a smaller buffer, but it cleared it promptly.

What is it with chins? Why did I take so many photographs of chins? What was wrong with me? Perhaps I was subconsciously thinking of the figurehead on the prow of a ship. I'm not sure why the Royal Navy thought that putting naked women on the front of their ships would strike terror into the enemy. Especially given that the enemy were usually French or Spanish, who love naked women and are familiar with them.

The last image is of Ulorin Vex at the Heygate estate in London, with the Strata in the background. There was a man cleaning the windows right at the very top of the building, and I hope he gets paid a lot of money. Cleaning the windows of a skyscraper would be a fantastic job if you were a photographer, because you'd be able to shoot panoramas of London all day long. And if you had a rifle and plenty of ammunition you could basically own London, at least until someone comes along with a helicopter. Or a gust of wind tips you out of your hoist.

Still, in its day the 10D was only one step down from the range-topping 1D and 1Ds and no doubt plenty of people were thrilled to get their hands on one. It seems beastly to rag on such a faithful servant. Nonetheless I curse its slow buffer and slow image review and wish its output was cleaner at ISO 800. Infrared photography generally requires a tonne of post-processing, pushing and pulling and contrast enhancement, and that tends to magnify the noise and grain.

A few months after the 10D came out, Canon released the cheaper 300D, which was the first budget-priced digital SLR and sold loads. They're readily available used but I'm wary of their long-term durability. It seems a shame to spend money on the camera and more money on the conversion, only for the shutter to fail after six months. The 300D wasn't much smaller than the 10D and it seems a bit pointless nowadays (the 350D was a great improvement, with a wider range of custom functions, a smaller body, and a slightly higher resolution).

Unlike modern SLRs, the 10D's infrared filter is weak enough that you can use an unmodified camera to take infrared photographs. You need to screw a visible light blocking filter on the front of the lens, and the exposure times go right up; the following was shot with the Olympus 21mm f/3.5 above, at f/3.5, on an unmodified 10D, with an exposure time of five seconds at ISO 100:

You could get by with shorter exposures in blazing sunlight but you'd need a very fast wide lens and higher ISOs to take photographs hand-held, and of course the viewfinder is blacked out, because you have an IR filter screwed onto the lens. For hand-held work with sensible exposure times you need to convert the camera into a dedicated infrared machine.

CONVERTING THE CAMERA
You can in theory convert the camera yourself. Lifepixel show you how to do it here, and they even include instructions for the 10D, complete with a detailed dissection of a 10D. If you were a digital camera you'd probably find that tutorial either immensely disturbing or very kinky. There's something seductive about the idea of tying someone up and having your way with them, and they can do nothing about it; but that is another topic for another post.

The process requires, amongst other things, a "soldering iron and desoldering wick or desoldering gun", and when I read the words requires a soldering iron I cease reading. Also, anything that requires carefully de-sticking stuck-on things is more bother than it's worth. I'm talking about dissecting a camera, by the way, not tying up a person. You'd never use a soldering iron on a human being.

Therefore it is common for non-technical people to send the camera off to have it converted. In the United States, Lifepixel seems to be the most popular choice, or at least they have the most visible internet presence. I do not live in the US, however, I live in Britain. I have failed in the lottery of life. In theory I could post my camera to them, and some people do this, but I worry that UK customs will slap a huge charge on the device when it comes back. Fortunately there are a couple of companies in the UK that will convert your camera, e.g. literally two, at least that I know of. Which one did I use? The first one that offers to convert my next camera for free, that's who.

Here's what the sensor looks like with an infrared filter on it, looking like an evil black hole into the camera's heart of darkness:

Yeah, digital. Just in case you forget, and try to put film in it.

There are different strengths of infrared filter. The filters are measured in nanometres, nm, with the larger numbers being stronger. Mine blocks electromagnetic radiation with a wavelength shorter than 720nm, which cuts out most visible light except for shades of deep red. Post-processing can separate and work with this colour information to produce odd-looking colour infrared files. Stronger filters, 750nm and above, leave the camera with no visible light to work with, and so you are restricted to black and white images. Weaker filters, from 600-720nm, pass more colour, although because it's biased redwards the results still look odd.

The EXPOSURE
The camera's exposure system isn't touched by the conversion process. It measures visible light, and is generally blind to infrared, and so in practice automatic exposures tend to be spoofed when there are strong infrared sources in the frame. Sunlit trees and foliage tend to be greatly overexposed; the lightmeter sees and exposes for the tree's visible light signature, while the sensor sees a strong blast of infrared. As a consequence I tend to use minus one stop of exposure compensation almost all of the time, minus two on very sunny days, of which there were precious few in England in the latter half of 2010.

There's nothing to stop you putting an IR filter onto the lens in addition to the converted filter inside the camera. This is akin to wearing a condom on top of a watertight diving suit as a means of birth control, or just because you enjoy that kind of thing. You might want to do this if, for example - e.g. use a second filter, not wear a condom on top of a diving suit - if the converted filter is relatively weak, and you want to block all traces of visible light altogether. This has the twin disadvantages of blacking out the viewfinder and confounding the camera's exposure system, but on the positive side the exposures are still in the hand-held range. I have briefly tried this, the end result resembles the output from my DCS 560, totally black and white.

On reflection, it's more like wearing a condom after having a vasectomy than putting a condom on top of a diving suit. You can take the diving suit off, see. With that mental image in place I want you to read the next section, after this photograph of Boris Johnson's office, which I took from a helicopter using a tilt-shift lens:

It almost looks like a miniature, doesn't it? You can see that Boris Johnson's house has been rubbed smooth. This is because women slide down it. It's a fertility ritual, you see. The women hope that some of Boris Johnson's mojo will rub off on them. So they slide down it, into the scoop. The whole thing is basically a pagan sexual epicentre right in the middle of London, sited right next to a bridge that opens up in order to let ships pass through it. The symbolism could not be more obvious. But what's so wrong with pagan sexual worship?

I don't usually do repeats, but the following image was shot just bottom-centre of the above, facing the same direction, no women in sight (they had all gone home):

Beyond the basics of exposure, you must find something interesting to photograph, and then line up the shot in an interesting way. Then shoot and check the histogram and dial in minus one exposure compensation and shoot and shoot; then have a drink and something to eat, and later on review the hundreds of images you shot, and then select the three good ones.

That's not specific to infrared photography, it's photography in general. The crucial thing is to make people think that those three good shots were the only shots you took, and that they were deliberate, and that every shot you take is good, if not great. Otherwise people will think that you're no better than them, and that you were relying on random chance rather than your genius. You have to convince other people that you possess a mental greatness that they can only dream about, and that you are not like them. Doesn't matter if it's true or not. That's your number one priority as an artist. You are not like them.

The LENS, and FOCUSING
I used a Samyang 14mm f/2.8, which becomes a dead sharp 22mm with a tonne of barrel distortion on a 10D, which PTLens will correct. I don't have any APS-C ultrawides and so the 14mm was an kind of emergency choice; in practice it suits me fine. I came close to selling it, but decided that it's worth more to me as a dedicated infrared lens. I used it all the way through the previous posts in Venice and Barcelona and Montserrat as my only infrared lens, and I have come to the conclusion that 21-24mm is my bag, in terms of focal lengths.

Some lenses have a "hot spot" in the centre of the image when used with infrared; a small patch of increased brightness of differing intensity. The 14mm has this, although it's a kind of diffuse zone that is, most of the time, not obvious. The lens also suffers from flare, as mentioned in the previous post. Here's some of it with the same building I set to music a while back:

The world is set to music when there's music in your head.

There's another reason why the 14mm suits me. Infrared light doesn't focus to the same point as visible light, and so your camera's autofocus will be useless; even the optical viewfinder lies to you, so manual focus isn't the answer. The company that converts your camera can adjust the autofocus system to suit, but in my case this only seems to work with one lens, an ancient Canon 70-210mm f/4. Every other autofocus lens I have tried fails to focus properly. Only the 70-210mm f/4 works, and as a consequence of this every single one of the people portraits in this and previous posts was shot with this lens.

With manual focus lenses it takes a bit of trial and error until you work out how to focus to infrared infinity. Shooting a portrait at close range at f/1.4 would require a tape measure and lots of patience. The Samyang 14mm is odd, in that infrared infinity focus coincides exactly with the infinity focus mark on the lens, which is also at the extreme clockwise end of the focus ring's travel. Therefore, in order to achieve infinity focus all I have to do is twist the lens as far as it goes clockwise and hold it there, which leaves me free to worry about composing the image. After stopping down to f/11 everything from a few feet to infinity is in focus. Most of the landscape images in this and previous posts were shot at f/11 or f/8, varying the ISO to keep the exposure above 1/30th or so.

And that is the technology. In the next exciting episode I will show you how to turn the muddy-browny-red smudged mess that a converted camera produces into a sharp contrasty work of colourful artistic brilliance which you can put onto a blog so that ten people can scroll past them in order to get to Ulorin Vex's breasts.

Or I might write about something else, and not post part two for six months.

EDIT: There's another thing. Infrared radiation tends not to be scattered by haze, and so infrared landscape photographs often have an unreal clarity, as if shot on the moon, where there isn't any air. Without haze to provide a depth cue the image often looks a bit flat, as if it was a well-lit miniature rather than a distant mountain, but on the positive side the camera captures nine metric tonnes of detail. Here's a shot taken from Montserrat's monastery:

Here's a 100% crop with a little bit of sharpening:

That dot on the road is a car, and I can tell it's a car and not a truck because the next picture has some trucks where the car used to be. Judging by Google Earth, the car is about one and a third miles away and two thousand feet down. If I remember my maths correctly there's a clever sum you can do to work out the length of the third side of a triangle if you know the length of the other two sides, and this is the first time in my life that I've ever felt the need to find this out. (guesses) It's probably something like a mile and a half or so.

So, yes, infrared photography allows you to see a Spanish car from a mile and a half away or more.

Monday 15 November 2010

Infrared Italy III: Barcelona II

The fundamental problem is that Infrared Italy is alliterative, and Infrared Barcelona is not, and if it comes to a choice between something that is pleasing and something that is true, I pick the former. Here's some more of Barcelona - and also Montserrat, which is in Barcelona province - shot with my infrared camera.

There aren't any alliterative synonyms for infrared. I could have tried Beautiful Barcelona but that doesn't explain the fact that these photographs were taken with an infrared camera.

Barcelona: Beyond Black might have worked, but people would wonder why I was talking about black in a post about infra-red.

Barcelona Bang Bang Boogaloo is catchy but doesn't make sense. That doesn't mean it's bad; a lot of things don't make sense.