Aperture & Depth of Field

Along with being one of the three elements of exposure (ISO and Shutter Speed will be covered later), Aperture also determines the front to back sharpness of an image, more commonly known as DEPTH OF FIELD.

Aperture is measured in units called f-stops (after more research, I may add another post on why exactly they are called f-stops) , which is noted on one's camera in the form of f3.5-f5.6 (on the standard zoom/kit lens for instance) and a fixed value (one value throughout) on 'Prime' lens (one with a fixed focal length e.g. 50mm), this has the same aperture value/f-stop through out. Some zoom lenses also have a single aperture value throughout the whole range (i.e. 24-70mm, f2.8). Such lenses can be referred to as 'fast' lenses, for they permit more light onto the sensor, and allow for faster shutter speeds to be used. Not to mention, allows more creative scope for a much shallower depth of field.

A rule of thumb for understanding Aperture : the lower the number, the wider the aperture, which means the lens is allowing more light to hit the sensor. Furthermore, each f-stop allows either double of half of the amount of light as the next full stop along (e.g. f5.6 allows double the amount of light as f8; f11 allows half the amount of light than f8). There is a very good video on YouTube that explains how exposure is measured in terms of 'stops of light' in the most simplest terms possible. When I find it I will endeavour to add it below. Conversely, if you want to know about the relevance of the numbers involved, or indeed the formula used to work-out depth of field, then I may post something at a later date.

So the depth of field (otherwise known as 'depth of focus') is determined by: aperture setting, focal length and distance from subject. Below is an image showing the passage of light at particular aperture settings, and how- at wider apertures- more light is directed toward the subject (be this close or far away).

So, when we shoot portraits of people, for example, and the person in the foreground is used as the selected point of focus, using a wide aperture (anything up to say f5.6), this person will be completely in focus, and the focus will drop off towards the back of the image (hence 'front to back sharpness'). So the wider the aperture (low number), the greater the depth of field (narrow and wide in the above diagram) in the image. For landscapes we opt for a very narrow aperture setting because we want everything in focus (anything from f13 to f22 and beyond, but I often use f11 to shoot buildings).

There was some debate in the very first session over whether you can create the effects 'playing' with depth of field affords you with such a standard piece of kit. Personally, I don't think you can. When you look at how depth of field is used with a lens that can go as wide as f2.8 and wider, I think its fair to say the standard kit lens is lacking in something. After all, depth of field is used as a means of creativity- a way of telling a particular story through an image and creating context- and to do so I think a lens allowing you to get as sharp as possible (even when zoom) has the scope to tell this story. This is not to say the kit lenses we get with our cameras are completely useless, but the prices of fast lenses do seem to tell this story.

Getting to Know You

For the first session with Richard we were asked 'get into pairs', and take pictures of one another as a means of getting to know each other. I was paired with Nabiha, a trainee Make-up Artist, originally from London. She hopes to combine the disciplines of make-up art and photography, and who can blame her, for they are a match made in heaven. Below are some of the best portraits I made of Nabiha.

Some just work dead-central. Apologies, but I have actually edited this in CS6, despite this coming much later in the course. One thing you'll learn about me and the way I work, is I'm a chronic perfectionist. I'll probably make myself ill during this course (lol).

With the leading lines of the corridor, telling the 'story' that she is indeed a part of 'student life'

Nice one this. Oh, they're all shot at f5.6 by the way (more about this in my next post on Aperture/Depth of Field)

Not sure if this is my best of the four. What do you guys think?

JAspinallPhotography: a Brief History

I'm using this as an introduction to my new blog, in which I hope to showcase some of my favourite images from the past two years, along with new work and examples that emerges from the Level 3 Diploma in Photography that I have just started at The Manchester College.

Photography has excited me for many years, but it wasn't until starting- and subsequently completing- the Level One and Level Two courses that my understanding of this art-form expanded dramatically.

I like street photography, and photographing the built enviromnment. I am also gaining more of an interest in documentary, for I like the way subjects can be shot as a part of their everyday environment, adding a context and a narrative to the image. As an English graduate, I like stories, and hope to do with my images what- in a previous life- I did with words.

Photography for me is about the convergence of the Scientific, the Technical and the Aesthetic that occurs every time the shutter is pressed.

Below are some of my favourite images:

This image seems to have rendered all subsequent images as 'the difficult second album'. It will be difficult take a picture that will receive the same appreciate. Difficult, but not impossible.

Released from Strangeways earlier that day, this unusual character represents what I love about Street Photography and the people you're likely to meet.

I'm just showing off now! This- and the picture below- are two of my 'Hulme Collages', which I created  to celebrate having lived in the district for a year. I live in Denton now. Struggling to find inspiration to be honest! 

I prefer this to the above. If the above is the commercial view, this is perhaps a more inspired piece. I used approx 13 layers in CS5 to mix both images and the written word. During my time in Hulme, I collected roughly 80% of all my ASDA till receipts, so you may notice I have scanned a couple of these to create the piece. I have also incorporated the practice of creating in the collage itself by scanning some notes I made on Photoshop. I will be exhibiting these two and more at:

http://www.z-arts.org/events/celebrating-manchester-launch/

A popular cityscape shot of Salford Quays at dusk, taken from Trafford Bar bridge. This may well feature in my upcoming exhibition at Z-Arts (link above).

Humour... I shot a whole series of these. It epitomises the sense of 'theme'/grouping images in photography. I had such fun shooting this little fella. See the whole series here: https://www.facebook.com/jonaspinallphotography

This is one of my favourite images from the very first wedding I was paid to shoot.

And this is a personal fave from one of the two wedding's I have worked as Assistant Photographer

In terms of telling a story, I really like this image shot at Yorkshire Sculpture Park last year. The sense of togetherness runs alongside the uplifting words on the bench itself.