Ok so it’s been almost two months since my last post! The irony is that because I have been very busy I have a lot to write about, but because I’ve been really busy I have not hand any time to sit down a create a post.

However, I do think this blog is important, as important as any other part of the job I do as a photographer. With that in mind I’m going to be trying to hit two posts a week. And posting more pictures, after all this is a photography blog (I’m not going to repeat the cliché concerning a specific volume of text).

In the meantime here’s a list of cool stuff I’ve seen on the internet:

• 78 Photography Rules for Complete Idiots A long and in places pretty tenuous (”It’s better to photograph clouds, when there are clouds”) list of the pretty blindingly obvious, worth a read though to see how many ‘rules’ you have have broken and actually produced great photos (I make it 24)
• Evolution of Photoshop: 1988 – 2009 A trip down memory lane, if you’re anything like me!
• Let your darkside outGood marketing, even better T-shirt!
• Manhattanhenge History repeats itself. Some very interesting images.

MG

I was reading through the proceedings of this year’s SIGGRAPH (Special Interest Group on GRAPHics and Interactive Techniques) conference - as I’m sure we have all done at some point in our lives - when I came across a very interesting paper.

The conference generally concerns computer graphics and image analysis however the following title has a very practical application in photography: Dark Flash Photography. No we’re not talking about Joey Lawrence’s promotional images for the film Twilight, but instead a way to take flash photographs without people objecting, or even noticing!

The gist is that you can ‘hide’ the pulse of light outside the visible spectrum thus making it appear as much as 200 times dimmer than a regular flash. This requires an IR enabled camera and suitably modified flashgun. The use of flash for photography can range from an mild annoyance to a dangerous distraction in certain circumstances, which leads to the use of shutter speeds far slower than would be ideal. The dark flash solves this problem but creates a new one.

left to right, IR image, natural light image, combined image, long exposure natural light (for reference)

Capturing light in the IR part of the spectrum doesn’t allow natural looking colours to be recorded. Dilip Krishnan and Rob Fergus solved this problem by taking two exposures, one with the dark flash and one high ISO natural light photo immediately after it. The clever part is that the dark flash image can be used to guide to de-noise the high ISO image far more effectively that any other noise reduction technique. Simply put if you see an edge or spike in the natural light image and there isn’t a corresponding edge in the IR image then the point is probably the result of noise. The actual process is a little more involved, I’d recommend anyone technically minded to have a look at the original paper.

The result is a clean image with natural looking colours. The post processing required is complex, and there times when the approach wont work well if the subject moves between the two exposures (shooting fast paced sports for example). However if you have an IR enabled camera and like black and white images I can see this being a very valuable technique when in many circumstances, and indeed the only real solution to the problem of dazzling people with flash.

MG

I originally got a macro (close up) lens mainly to do jewellery/product shots, I didn’t really intend to do much nature photography with it. A while ago whilst doing some late night internet shopping I had a moth buzzing round the lightshade being a nuisance. I turned the light off hoping it would go away but it just landed on the computer monitor instead. I tried (and failed) to get a shot of it using the monitor as a lightsource (it was too dim). I then decided to have a go with the flash not really knowing what to expect. Considering it was all done with no preparation I was pretty pleased with the result. Here’s the set up if you don’t believe me!

The chance to do some more nature macro photography fell into my lap recently - though I warn you if you are at all afraid of spiders then I strongly suggest you don’t click through to the second part of this post!

About a week ago I brought my reclining garden chair into the living room to rescue it from a thunderstorm. The next day I noticed something moving between the arm of the chair and headrest which on closer inspection turned out to be a nest of recently hatched spiderlings. Again I immediately went to grab my camera to take some photos.

Lighting-wise I used an Elinchrom monolight with large silver reflector as shown, mainly because I’d just been using it for something else so it was already set up. A lot of light makes things easier but as before you can get away with a small speedlight due to the possibility of moving it in close.

The back of the chair is providing the background, showing up white as it’s directly in front of the strobe on full power. As well as not showing the dirt on my sensor as badly I decided shooting from another angle to give a darker background would suit the subject - I wouldn’t exactly say that I’m a fan of spiders but I was originally attracted by the bright yellow bodies and black markings. Following an internet search I later determined they were completely harmless - the offspring of Araneus Diadematus or common garden spider).

The spiderlings were barely a few millimetres in size. The definition of macro is the ability to focus on an object around 36mm in width at a distance at which it fills the frame, so these creatures really fall into the supermacro category however the kit required for that is pretty specialist and things start to get really difficult as depth of field and light gathering becomes a real problem.

As it is I was able to shoot at f/11 this was just about enough to get several spiders in focus if they were roughly in the same plane. I had started at f/32 but was getting considerably softness due to diffraction. Focussing was then a case of setting the lens to the closest distance and moving the camera.

I still wasn’t really liking the results, so I had the idea to shoot along the web, producing the above. Despite getting fewer individual spiders in shot the expense of getting fewer individual spiders in focus, I liked the abstract nature of the shot (click for larger).

I haven’t talked much about lighting. When you’re less than a centimetre tall a bare flashhead appears the size of a movie set scrim hence pretty much any lightsource would be considered soft. Direction, then plays the most important part and in this case it was easier to leave the light were it was and shoot from another position. This final image is probably the best of the set - there’s a little foreground detail for context and the light is more dramatic (click for larger). I’m still feeling my way through this stuff, I certainly wouldn’t consider myself any sort of expert but if I get any more opportunities for some macro nature photography I’ll let you know how I get on!

MG

Came across this interesting project today - the goal is to devise a scheme to compress an image so that it can be transmitted in a single tweet, which comprises a mere 140 characters - barely long enough to describe the four course meal you’re part way through consuming.

To illustrate the magnitude of the task at hand, that opening paragraph weighs in at about two tweets. Quasimondo’s solution utilises some neat tricks.

Firstly using Chinese characters increases the available storage as the set is larger than the standard western character set (which presumably enables anyone fluent in Cantonese to exchange essays over twitter).

The clever part as far as I’m concerned is the decoded image is generated using the Voronoi tessellation, which means each of the multi-sided shapes that make up the image can stored as a single point with x and y coordinates (plus a colour).

This enables large and potentially complex regions to be transmitted very efficiently. This does, however require the careful placing of points to generate salient shapes, whereupon the next clever idea is utilised. The points, or ’seeds’ are generated randomly at first and then mutated over many generations of a genetic algorithm to find the arrangement that best replicates the original image.

Click the thumbnail for a more complete description from the man himself.

MG

By and large telephoto lenses are easy to design, optically but require some very large [read expensive] elements if you want a fairly wide maximum aperture. In contrast wide angle lenses have to bend light much further and apertures can only be so large without the use of sophisticated [read expensive] optical corrections.

The humble 50mm, once the standard ‘kit lens’ bundled with new SLRs happens to sit at the crossover point. The focal length is long enough to employ a simpler non-retrofocus design, which is tried and tested, with inexpensive elements keeping the manufacturing and assembly cost down. As a result you get a very large maximum aperture and good optical performance for what is relatively little money.

And mounted on a full frame 35mm body the selective focus is sublime…

MG

I am now on twitter so go and add me if you want to know more about what I am up to. I promise I will only post about photography projects, updates and interesting things I come across, not about what I’m eating for breakfast!

Anyone who’s seen my flickr stream and/or blog post knows I’m a big fan of the Orbis ring flash adaptor. They recently held a competition and although I didn’t win I was pleased be in the top 10 - considering the high standard of photos selected! My image (which accompanies this post) along with the other finalists & winner have been added to the Orbis samples gallery here.

MG

I came across “Dave Cross’ Fix it challenge” via Scott Kelby’s blog. Basically each week Dave posts an image in need of some serious retouching, participants fire up photoshop and do their worst, posting the resulting images in the pool from which winner is chosen. I had been on the look out for something to practice my photoshop skills on, and being a highly competitive person I couldn’t resist having a go.

This week’s image is a period photograph of a woman standing in front of a painted background. My immediate thoughts were, on top of fixing the obvious damage, I would attempt to restore the colour that would have been present - had colour film been invented at the time! This is something I’ve not attempted before on a photograph so it’s an ideal learning opportunity. In the end it turned out to be somewhat more challenging than I had expected! What follows is a step by step breakdown of what I did and why I did it…

The original image looks something like this:

Firstly I rotated the image, cropped the border and fixed the corners. Next job was to repair the tears. This is a fairly mechanical process, working along each tear I copied adjacent areas with similar appearance to fill the gaps (a process made easier by the lack of colour).

Having sorted the major tears I removed dust spots accumulated during scanning, and desaturated the image to produce a blank slate to begin colouring:

The original had an uneven exposure across the print so I adjusted the levels independently on several different areas to maximise the contrast. I applied a slight noise reduction - I didn’t want to lose too many details as the image wasn’t very sharp to begin with. To this end I sharpened the image using the high pass filter:

Next step is to colourise the image. I decided not to go for subtlety (if I was going to spend time putting colours in I wanted it to be bright!) so using a little artistic license I thought I’d paint a sunset in the background. In the past I’ve coloured line drawings by setting the greyscale image to multiply in order to darken a layer of colour placed underneath. I started to apply some colours in the same way but quickly realised I wasn’t getting the result I wanted:

I went back to the drawing board thinking of ways to separate colour from tone. I immediately thought of the L.A.B colour mode. That wasn’t the answer by itself, as that would require painting colour onto two channels simulataneously. But it did get me thinking along the right sort of lines, and after some experimentation I was able to recreate the way that L.A.B mixes colour and tone using the overlay blending more.

Sampling a few colours from a sunset image from stock.xchng I added colour to the sky. By selecting each section individually I could layer up the colours beneath the greyscale so they overlapped each other slightly, avoiding gaps. For certain areas I copied the greyscale image and applied a gradient overlay, to enable me to apply different colours to different brightnesses, for a more realistic look. For example specular highlights on wood are usually grey, even if the wood has a rich colour. To replicate this, the gradient overlay I used went from white, to brown and then to black in the shadows. This technique is particularly important for skin as it reflects light differently from most objects. Despite trying many gradients I was unable to get a completely convincing result:

The left hand part of the backdrop was coloured using a gradient then additional details were roughly

at this point I’m trying to replicate a photo of a painting, so accuracy isn’t of the upmost importance (at least that’s my excuse). Likewise, instead of painting in the trees on the right, I just let the sunset colours take over. This is the colourisation result:

Next I cropped the image slightly to remove an awkward area on the right and to remove some of the top of the image, which lacks detail. To give the image a ‘digital camera’ look I added a fairly large amount of colour noise. This also served to cover up some of the less convincing parts, and increase the perceived level of colour detail. Finally I tweaked the levels and colour balance of the whole image:

The above image was shot during a talk I gave to the University of York photographic society (thanks to Jens for letting me volunteer him for this demo). The topic was light, more specifically how nothing to do with light (and therefore colour) is absolute - it’s all relative.

The rim light coming in from the right has a strong yellow coloured gel in front of it but what if you don’t happen to have a yellow gel handy? Well all is not lost, provided you have a blue gel. By putting a blue gel on main light, the rim light - despite being white* - is yellower than the main light:

White balance is the process of picking an arbitrary point on the spectrum and declaring it to be “white” (something our eyes do without us realising). By choosing the white balance in order to make the blue light white, the colours shift accordingly and we end up with this:

which is surprisingly like the first shot (especially since I grabbed a yellow and blue gel that looked about right, without actually testing!)

Ok, so this isn’t the most useful technique in the world, after all if you one colour gel you’re likely to have others as well! But what about if you can’t gel one of your lightsources, what if one of your lightsources is the sky?

MG

_{*as in the colour of daylight. Residents of another planet would probably have flashes which produce a different colour light as “white”.}

This headshot of Oliver, editor of law journal Ebor Lex, done in a standard meeting room in a very short timescale. I thought it would be an interesting subject for a “stream of consciousness” post showing every shot that was taken during set-up and and trying to explain what was going through my head at the time. This is not supposed to be a perfect example of how it should be done, merely a record of how it was done.

It’s important to have some idea what you’re trying to achieve before you start so I decided I wanted something edgy, like this shot but with a more traditional background. That look was achieved by having a pair of softboxes very close to the subject, angled slightly toward the camera so I started off with the lights in that position.

No light meters no modelling lamps, what follows is exactly what I saw on the back of the camera at each stage…

I didn’t have a wide lens with me so no setup shot but here’s a diagram to help you visualise what’s going on.

First step, set up the background light (a projector screen makes the perfect background). I used a bare speedlight angled down so that the natural falloff would provide a nice gradient from light to dark. It’s close to the screen with no light modifiers so it will be nice and bright so I set it on something like 1/4 power on for faster recharge. The camera is in manual, max shutter speed I can use with flash is 1/200s, for safety I go one setting lower, 1/160s. Middle of the road aperture of f/5.6, two stops down from wide open. ISO 100. Subject in place. Bang.

The image as it comes up first is on the left, I hit the “info” button straight away to get the histogram view (right). Background is a bit darker than I wanted, so I crank the flash up a stop. Bang.

That’s better. The blinking area on the info screen indicates pixels which are blown out (i.e. have hit 100% white) since the camera can’t record more than 100% white detail is likely to be lost*. As there background is plain and I want it to be white I’m not bothered by this. I turn the background light off and the main w/softbox on. It’s in close so power is set low. Bang.

Notice the timestamp (14:46), one minute has elapsed so far! The light is more extreme than I wanted. Move the softbox toward me a little. Talk to the model, explain what’s going on. Bang.

Light is still too oblique. Move it round a lot, which involves moving the table slightly and costs some time. Bang.

Getting there, but need to move the light a little bit more to throw some light on the other side of Ollie’s face. Decide to move the tables out of the way completely, which takes a few minutes (pro-tip: move the furniture before you begin, or better still, get someone else to do it for you). Bang.

That looks like what I want but it’s overexposed. Instead of moving I drop the ISO a stop to 50 (there’s very little difference between ISO 50 and 100, we’re not taxing the DR or noise here). Bang.

Little is still a little to bright (see blinkning image, right). Can’t lower the ISO so I have to power the flash down a little. Bang.

Main light is how I want it, now I position the fill light. I’ve deviated from the original symmetrical setup in favour of a strong light from the left so I move the smaller softbox back to provide a glancing rim light. Use the same setting as the main light, knowing it’ll be darker as it’s further away. Bang.

Looks pretty good, there is still a little bit too much shadow on the face so I move the fill light closer in and toward me. Reassure model that we’re almost there. Bang.

Both lights are how I want them, The image is a little overexposed but nothing RAW can’t cope with. The purpose of turning off the back light was check the main lights don’t interefere with it. As you can see they clearly do, but they add a uniform pattern of light so all I have to do is turn the background light down a stop to compensate. Bang.

All looks fine, take a step back (I’m using a prime lens) to give wider view for more cropping options. Accidentally nudge the shutter speed to 1/100s (the flash is easily overpowering the flourescent room lights so it’s not a problem). Explain to the model we’re going for a take. Bang.

Zoom in and check the pose, all looks good. Explain to the relieved model he can relax now. Time from the first test shot to completion: 11 min. Pack up, go home. Here is the final lighting set up:

I filled in the shadows a little in the raw conversion, applied a few curves adjustment layers in photoshop and tweaked the colour balance. Finally the image was rotated slightly and cropped, leading to the finished version (click for larger):

MG

*the histogram/blinking actually shows information from the JPEG preview embedded in the RAW file so you usually have some latutide to recover the highlights even if they appear blown on the camera screen.

Posts have been a little scarce recently as I have been very busy. This does mean however that I have a lot to talk about, so stay tuned! In the meantime here are a few interesting things I’ve come across recently.

♦ Firstly, one of the reasons I love the internet: honest product reviews by people with no mandate to keep manufacturers or editors happy, such as Scott Kelby’s review of the Jobo photoGPS, a piece you’d be unlikely to find in a photography magazine! (ps if you haven’t read it already check out The Online Photographer’s review of the Nikon 24-120mm ƒ/3.5–5.6G, which is in a similar vein)

♦ Canon have announced the latest in the line of affordable DSLRs, a market segment it created back in 2003 with the release of the Digital Rebel. Check out a hands on preview of the new 500D here. The one good thing about this announcement for amateur photographers (who want to shoot pictures, not video) is that it will likely push down the cost of the 450D.

What’s wrong with the new 500D? Well they’ve equipped it with a 15 megapixel sensor, when there are widespread concerns that 15mp was too much for the 50D. To put this in perspective, 8mp is still fine for the professional sports shooters using the 1DmkII. The 35mm film that was used by some of the worlds top photographers for over half a century barely equates to 8mp. According to the stats of people visiting this site in the past year, the vast majority of users screen resolutions only correspond to a 1mp image (and that’s if it fills the entire screen). Don’t get me wrong, high resolution is not in and of itself bad, but I really can’t see including a 15mp sensor in an entry level camera as anything other than a marketing gimmick.

♦ At some point I’ll write an essay on film vs. digital, and my whole take on the debate. But to summarise, my position has always been that no matter how sophisticated the technology becomes it will always be the artistic vision and skill behind the equipment that dictates the ultimate result (until such time when computers become truly intelligent, at which point us photographers will be totally out of a job).

The sentiment was echoed by Michael Johnston in a recent post on The Online Photographer, but this time accompanied by a video which demonstrates the point far better than I could hope to do.

Disclaimer yes it’s a viral ad for Samsung and as a result you have to take what you see with a pinch of salt. But the point is it doesn’t matter if the entire thing isn’t 100% real, having seen “One Man and His Dog”, I know it could be done!