Exposure Explained…. via Beer?

F stops, shutter speeds and ISO can be confusing.

I like to think in terms of things I understand when trying to explain difficult concepts, and it happens that beer can be roughly equated to exposure…

F-Stops

So the F stop relates to how fast a beer flows from the pump:-

  • Guinness takes ages, that’s got a tiny flow – so that’s a small aperture, like F16, F22 or even F35
  • Hand pulled bitter comes out really fast – that’s like a fast aperture, say F1.4 or F2.8
  • Lagers and cider are somewhere in the middle, you’re looking at F5.6-F11 there

Shutter Speed

Shutter speed relates to how long it takes to fill your glass

  • Guinness takes ages so that has a long shutter speed – maybe 30 seconds
  • Hand pulled bitter comes out really fast – so we’re talking fast shutter speeds, 1/500th second is pretty fast, though most cameras go to 1/8000th these days
  • Lagers and cider are somewhere in the middle, 1 second maybe

The link…..?

Can you see how the 2 link… a slow pouring beer like Guinness takes a long time to fill the glass, whereas a fast hand pulled beer fills the same glass in a fraction of the time. In both cases, you get a full pint, but you just need to vary the pouring time because of the different flow of the beer.

What is ISO?

What about ISO then….

Well this relates to the size of the glass!

It’s actually the “speed” of the film, the sensitivity of your camera’s sensor, but glass size is easier to think about. It’s basically how much beer you need to fill the glass.

Lets say ISO 400 = 1 Pint

  • ISO 800 is like a half pint glass – i.e. it takes HALF AS MUCH BEER to fill it – it’s twice as “fast”
  • ISO 200 is like a 2 pint glass (or a litre stein you see in bavaria) – it takes TWICE AS MUCH BEER to fill it.
  • ISO 100 would be a 4 pint glass, it takes 4 times as much to fill!
  • ISO 1600 would be a 1/4 pint glass – so it takes a quarter of the beer to fill.

Keeping up….?

So lets gather all this together in camera speak.

  • We have a “flow of beer” = Aperture
  • We have a “time the flow runs for” = Shutter speed
  • Volume of the glass we’re pouring in into = ISO

STOPS – What Are They?

All these things are related closely by a unit called a “stop” – a weird name really.

Aperture, ISO and Shutter can all varied by “stops”, but they each have different names and “steps” between them. The Stops are named as follows:-

  • Aperture Stops – F1 F1.4 F2 F2.8 F4 F5.6 F8 F11 F16 F22 etc.
  • Shutter speed Stops – (units of time, measured in seconds) 1/1000th 1/500th 1/250th 1/125th 1/60th 1/30th etc.
  • ISO Stops –  50 100 200 400 800 1600 3200

All Doubles and Halves

The Shutter speed and ISO stops double or halve when you move along the list. This is because each “stop” is “double or half” of the neighbour.

  • 1/500th has neighbours 1/250th (double the time) and 1/1000th (half the time)
  • ISO 400 has ISO 200 or ISO 800 as neighbours.

Aperture Stops Are Strange

So why does aperture look so odd?

Well its a bit more complex, but each stop is about 1.4 from the neighbours – so there is a relation ship there. (it’s to do with the square root of 2 = 1.41).

So from

  • F1 to F1.4 is 1.4 times –
  • next is F2 (that’s 1.4 * 1.4)
  • next is F2.8 – (that’s 1.4 * 2.0)
  • and so on

So what does all this mean?

You have 3 variables which control the exposure of a picture – get them wrong and you’ll get a badly exposed shot. i.e.

  • if you don’t let enough light in you get a dark shot  (or a glass that’s not full if we talk about beer)
  • if you let too much light in you get a completely useless white shot  (or a load of beer flowing over the top of the glass on to the floor)

 

Here’s the critical thing you need to know – if you change one of the settings by a “stop”, you double (or half) the brightness of the shot.

Yes – remember, it’s all doubles and halves

  • If you increase the shutter speed by 1 stop, the shutter stays open for twice as long and you get exactly twice as much light on the sensor (or twice as much beer in the glass)
  • If you increase the Aperture by 1 stop, the flow of light is doubled and you get exactly twice as much light on the sensor (or twice as much beer in the glass)
  • If you increase the ISO by 1 stop, the amount of light needed to get an exposure is halved and you get an images exactly twice as bright (or you reduce the size of the glass by half – but the flow of beer is the same, you just may end up with some spillage if you’re not careful!)

Practice and Learn…

Exposure is best learned by using your camera, getting curious and trying various settings – I’d recommend putting your camera in Manual exposure mode “M”, and taking lots of shots and seeing what happens – go through each Stop in turn and learn that way.

There is a lot more to it than this, but next time you’re in the pub, watch the beers being poured and think “exposure”!

Exhibition in Abbot Hall, Kendal, November 2011

McFade photography are happy to announce that we will be putting on an exhibition at Abbot Hall in Kendal in November 2011.

The Abbot Hall website is here http://www.abbothall.org.uk/coffee-shop-exhibitions for directions.

The title of the exhibition is “North East-West”, taking photographs from the west coast to the east coast of northern England. These will include both landscape and urban scenes, coastal and countryside, giving a visual representation of the trip from the east to the west of the north.

Expect to see images from the Lake District, Manchester, Leeds, The Yorkshire Dales and many other places from Yorkshire, Lancashire and Cumbria.

The timing is perfect for Christmas presents as all the images will be on sale.

Also, there will be a “meet the artist” day, where I shall be at the gallery to talk about the work, the date for that is yet to be announced.

Everyone hates having their portrait taken…… at first

Out of your comfort zone

Unless you are a model, you are completely out of your comfort zone. No one has a camera pointing at them, like a sniper, in normal life. You will be uncomfortable.

So the photographers adds in all the lights flashing, other unfamiliar gizmos like reflectors, snoots and softboxes, and then puts you in odd positions; you really are in unfamiliar territory. Then if you’re on location, there will be people walking past and looking at you… that’s weird – they’ll be looking to see if you are famous!

Relax – it’s only a camera!

As the shoot progresses you will start to relax, photographers sees it every shoot. An amazing build up of confidence that comes as the rapport builds. Rather than feel scared of the lens,  it will, unconsciously, become your friend. You can do what you like and it never answers back – and a good photographer should recognise what you enjoy, and encourage it.

Photographer gives you constant feedback, showing you the shots on camera. You start to see how you are coming across, that your fears were unfounded, the effect the lighting’s creating  something you can never visualise whilst posing.

It takes 2 to tango…

This is also your opportunity to say what you think – if the clothes are not working, or you see something you need changing, we can take that on board and adapt, then check the results again.

It’s a happy feedback loop – the more you see the results, the more honed we can get the look. Also the more you realise that what seems “uncomfortable” when posing, actually looks great on camera; so you are far more willing to expand on the ideas.

In the Zone!

Towards the end of the shoot, you’re in the zone – some call it “flow” – as soon as the photographer has found a new location and set up the lights, you’re in position waiting for him.

Earlier, you were stood with your head down and hands dangling forlornly at your side – now you’re standing with great posture, using your hands and shades to add energy to the shot. You’ve forgotten you were ever nervous about the camera and hardly need any direction from the photographer.

Its at this stage where the magic always seems to happen – everything comes together and you get the “real you” in the photos.

And then the shoot is over!

Not because we end it when things start to flow, but the time flies by so fast the session seems over so quickly.

That’s a pattern I’ve seen over and over again – especially with longer shoots that take in multiple locations. Each new location is a new beginning, a new space for you to occupy and a gives you a new set of ideas.

Profile Shoot – The Jazz Guitarist

Chris Rae is a multi-musician, playing jazz on both Piano and Guitar with equal skill and dexterity. As with many areas of life, the internet has come to the musician’s aid and Chris is now partnering up with people across the world to create new and exciting tunes.

There are many of Chris’ tunes on Sound Cloud, which you can find here.

http://soundcloud.com/chrisrae

As with “social media”, your on-line personality is largely dictated by what you say (and play, in the case of the musician) , but your profile image is also a huge part of it. It certainly can attract people to click on you above many other “ordinary” avatars.

So we met to create some images for Chris’ profile and for future promo literature. Being from Ilkley I was keen to include some part of the town and surroundings into the shoot, we pondered the Cow and Calf rocks, but decided on a pebble beach on the river Wharfe. It is a lovely spot just down near the Lido, the river meanders past a curved, tree lined beach, creating all sorts of opportunities for a creative backdrop to his playing

Clearly we couldn’t lug a piano down to the beach, so we used the guitar, a prop which turned out to be very striking, with its light colour really standing out from the dark, misty background.

Chris wasn’t posing for these shots, he was playing – practising his diminished scales I think. That meant the hand positions and some of the amusing faces he pulled were all “for real”, which I think is what you’re after with a profile shot.

On a photography note – The huge advantage of the “strobist” style of lighting, which I’ve used here, is that you can get creative lighting in almost any location – without having to carry huge batteries and flash heads. Each shot on this blog used 2 flashes on stands, the rest was down to experience!

The Secrets of HDR processing….

HDR’s (High Dynamic Range) a very much maligned and misunderstood beast, most people associating it with eye popping colours and cartoon like portraits.

Well yes, you can very easily end up with images just like Loony Tunes if you want, but there’s not much use for them out there in the big wide world, so I’ll take you through a few of the steps I use to create HDR images like this shot of Lendal Bridge in York.

HDR requires 2 or more images to be truly “H” DR. The Dynamic range of a shot is the gap (usually measured in “stops” of light) between the brightest and darkest point in a photo, if you take several different shots at different exposure settings, you get an extended, or HIGH, Dynamic Range.

MISCONCEPTION: 1 exposure “tone mapped” is not actually HDR because you are not expanding the captured range; you are in fact just extrapolating the info in the one shot… anyway, that’s all a bit techy, so lets look at some pictures.

So first off we have the source photographs – here are my 3 source images

So you can see the difference between the light, medium and dark shots – the bright one lets us see the shade parts, the dark one retains nice details in the sky. You would struggle to get all that info in one photograph, having to resort to ND grad filters to darken the sky and all the problems they incur with city shooting.

The tool I use to “blend” these 3 shots together is Photomatix Pro –  a relatively cheap piece of software for what it does. It has a few methods of “blending”, my preferred one these days is Expsore Fusion – here’s what came out of the fusion process.

So the result is not actually too bad – bearing in mind I usually just guess the settings and batch process them, but the more you do it, the better your guess is 😉

First thing is to clear up any dust and get the verticals correct so things don’t look like they’re toppling over.

I also cropped it a bit as rotating the canvas to correct the verticals created some white spaces around the sides.

It’s a bit flat, so lets do a global contrast boost – that means to every pixel…

Cool, that’s looking a lot brighter now – there’s still a bit more of a boost I’d like to see in the water though, so I’ll do some “selective contrast” using masks and curves.

Ok – that’s pretty subtle, but the water has a brighter sheen to it, and notice the sky top left, that was dark on the previous shot – common in HDR – so I lightened that too.

Right, now I think the stonework and bridge could do with a bit of a sharpen – so on this next image, I’ve applied some selective sharpening using again, a mask.

At this size, it’s a struggle to see the difference, but at 100% at 4000+ pixels, you can see the stonework popping out quite a lot – that’ll look really good in print.

I think we’re nearly there, though to me it still looks a bit wierd…. why?? BLUE! The blues look a bit false, so I’ll open up Hue Saturation, select the Blues and reduce the saturation, and maybe do the same with Cyan. Here’s what we get…

Phew, that looks far more “real”. I think that’s about done for the colour version – so save that away safely.

Now lets create a mono.  I have to confess that since I got Nik Silver Efex, virtually all my mono conversions are done with it. I used to use “Channel Mixer” and then “Black and White” in Photoshop, which are fine, but Silver EFEX is the best plugin for mono ever made and will transform your work. There’s no point describing what I did in Silver Efex, so here’s the result…

Quite a difference there – the software has introduced some noise into the sky, so I’ll run that through a Noise Reduction package and get our final image…

Am I tempted to get dodging and burning the Silver EFX output? Well sometimes, but in general, it gives results like these and they are amazing.

So that’s it really – I’ve taken you through the steps I typically do on an HDR architecture shot. Seems a lot of work, but it’s very rare that this takes too long – it’s a technique you can do really fast with practice.

If you are interested in learning more about this, both from a shooting the source images to processing in Photomatix/Photoshop point of view, then drop me a line at info@mcfade.co.uk.

5 tips for Night Photography

It may be heading towards Spring now, but there’s still time to make the most of the dark evenings with you camera.

Here are a few ideas and tips….

  1. You really need a tripod for all but the most creative “camera moving” shots – this is because the low light means you need long shutter speeds, often up to 30 seconds or more. There’s no way you can hold the camera still that long and not move it – giving blurred shots.
  2. Try to include moving lights in the shots – the most obvious thing is traffic, be it from a motorway bridge as cars zoom past or on the pavement next to a road. The lights turn into glowing lines, but the car doesn’t show… its magic!
  3. Add your own light to the scene – you can increase the interest in a night shot by using a torch to illuminate different parts of the shot. You set a long exposure going on your camera, then switch the torch on and point it at the thing you want to light – move the beam steadily over the it and you will get a more even covering of light.

    Blue torch adds light

  4. Use a head torch. They may look very geeky and weird, but when its dark and you’re looking in your kit bag for something, it makes a huge difference having both hands free AND light in the bag. Also, if it’s really dark where you’re walking, its far safer to have a light on the floor.
  5. Zoom Bursts…. this is a technique where you take a longish exposure (say at least a second) and “zoom” the lens from one extreme to the other. This means that every point of light in the shot becomes a line. If you do it with the camera on a tripod, they become straight lines, if you do it hand held, they tend to be a little wavey. It’s a cool effect

    Zoom Burst

9 Profile Photo Types – Which Are You?

LINKED IN – TWITTER – FACEBOOK – all need a great profile photo

We all social media – we’re all on Linked IN, Facebook and Twitter, they all use profile photograph to identify us.

In most cases, this photo is the first impression people have of you!

So what impression is your profile photo giving?

profile photo

Recognise Yourself – The 10 Profile Photo Types?

1 Egghead – No Picture

Some have no profile picture, this leaves the picture holder empty or with a default grey silhouette. What does this say about you?

Having no avatar can give messages like:-

  • “You’re hiding something” or
  • “You’ve not bought into this yet” or maybe even
  • “You’re a spammer”

So if its not a good idea to leave your profile empty, you could still hide by putting up a stock images, perhaps a cartoon figure or something on those lines. This gives a more powerful message than the empty avatar, but you have to beware of the message its giving.

2 Cartoon Hero

Maybe taking on the persona of Captain Caveman is amusing for a few days, but perhaps a potential client seeing that on LinkedIn would get the wrong impression.

An exception would be to use your company logo, but only do this on company accounts, not personal ones. It promotes brand consistency across your social media platform.

3 Pet-Tastic

Other common avatars are peoples pets, which are usually very endearing and often invoke an “ahhhhhh” reaction, but it’s not really appropriate for business (unless you’re a vet or run a cattery/kennel)!

Maybe use these on Facebook – but not your LINKED IN profile.

4 Little Jonny

People with new children often use their baby’s smiling face as an avatar, which again gets the “ahhhhhhhh” reaction, and can act as an ice breaker if other new parents are looking at your profile, but its not really “business”. For some non-parents, the prospect of “baby talk” can be quite off putting.

profile photo

5 Be Brave – Show your Face

So we come to the portrait – are you big enough to let people see you?

With digital cameras, phones, webcams and probably the next generation of toasters, we can now all capture images digitally and get them online very easily. Just about every website has made it so incredibly easy to do so, its second nature.

6 DIY Photographer

Most portraits are “self portraits” that follow this formula:-

  • taken at arms length
  • the camera high above the sitters head,
  • often with a bit of arm on one side of the shot,
  • certainly an un-natural shoulder position and
  • usually with a facial expression they only ever have when taking a self portrait!

They are fine for the social side of the Facebook, they are friendly, engaging, easy to relate to and you can change them every day, keep people guessing what look you will have on the next day. But for business they’re not giving that “slightly serious” look which “means business”. All a bit heath-robinson.

7 Group Shot

Another favourite is the group shot (or just your face cut out of a group shot). These are usually taken in the pub after Tequilla Slammers, arms around your mates, bleary eyed, rosey face and generally looking very very merry. Fantastic for social use, conveys that fun loving persona and the fact that you’re still able to party hard… but is it business?

8 The Wedding Shot

How about the “wedding shot” – not just the bride and groom, often the guests and especially the bridesmaids. These are photos of you looking at your very best, its a wedding after all. But what does it say about you…. maybe you only look good at weddings, the rest of the time… ?

profile photo

9 Get a Professional in

So we come to the professional photograph, this certainly gets across a feeling of credibility. The fact that you “value” your profile sufficiently to invest in great photos says a lot.

But not all “professional photographers” are the same. Its a bit like assuming that all authors write the same book or all artists paint the same pictures. They are a diverse breed, with ideas bubbling away in their brain like a cauldron full of magic potions. Some may be amazing at shooting woodpeckers or the Dales at sunset, but would have no idea how to work with a “human”.

It’s definitely worth researching the local pool of photographers rather than plumping for the first one you see.

You can do this easily on their websites, Flickr, Facebook and even Twitter. Google is an option, but the photographers who are on the top pages are there because of great SEO, not necessarily great photography.

Also ask for recommendations from your network. Take care to look at their portfolio, because the “look” they achieved for the guy who recommended them may not be what you are after.

Another approach is to go through your friend lists on social media, look at their avatars and find ones you like the look of, then message that friend to find out who did their shots, they’ll be more than happy to pass on their details.

profile photo

Get the Right Shot by Talking

Many business profile shots are quick affairs, shot in the office or in front of a blue background, shirt and tie (or equivalent for women), lighting which you got in your school photos and an expression that’s “old school” or solemn.

That’s fine and what many people want, especially corporates – it gives a strong impression and means business, but it doesn’t make you stand out from the crowd. Standing out for the entrepreneur differentiates them from the competition.

Ideally you should have in mind the kind of look you are after so you can talk it over with your photographer. You don’t have to get technical, maybe just mention a TV program or bring a magazine with photos in, or just try your best to say what you want to look like, that’ll give the photographer a great head start in his thinking process.

profile photo

Its also important to mention the use of the photos, as you can use them for things other than just your avatar. If you want to use the shot as a header image for a page on your website, then tell the photographer and they can leave space to the side of you. If it’s going to be a vertical panel down the side of your web page, the photographer can do that too.

If you want a “sense of location”, then organise the shoot at that location, so that you can have iconic buildings as your backdrop – there’s no rule stating that you need to be in the office or studio, we can go anywhere and make a studio quality image these days.

profile photo

If you need to convey a selection of moods, expressions or looks, discuss this with the photographer – they will make sure they cover all those as the shoot progresses.

If you need some business-wear and some casual-wear shots, bring along a change of clothes – maybe just a different top or coat will do for location shoots, a full change is possible in the studio. You can always nip into the a hotel and change a top in their toilet if need be.

Think about where you are most comfortable or where people will associate with you – maybe its in the city, maybe a class room, maybe in the board room, maybe on the fells and moors, maybe in the bar…. you know best.

The more information and ideas you have to start with, the more you can aim for and the more likely you are to achieve the desired image…

…..and a strong image WILL give a fantastic first impression to anyone viewing your profile on social media

5 Tips for off camera flash

Flash is often seen as a necessary evil by many photographers, and when the flash is “on camera” (like most are) it can be a bit bland and create “bunny in the headlight” portraits.

However, get the flash (speedlite) on a stand and trigger it remotely,  you’ll see the true creative power of flash.

Here are a few starter tips.

  1. Take note of your camera’s “synch speed” – it’s usually around 1/20oth second. If you go faster than this, you’ll get dark areas on your photos
  2. Learn how to use your speedlite on manual flash power as most triggering systems don’t tell the flash how much light to emit – you need to learn how to control it yourself
  3. The amount of light that hits your subject depends on how far away you put your flash – and it’s an “INVERSE SQUARE LAW!” That just means that if its 1m away and you move it to 2m, you get 1/4 of the strength. Move it to 3m away, you get 1/9th, 4 would be 1/16th, 5 would be 1/25th etc.
  4. Most light comes from above, so get your light stands nice and high to make it look a bit more natural
  5. The best way to learn about light positioning is to experiment, if you’re digital, it’s free, so just try and try and try… if you can’t get a model, find a statue in town or even in a grave yard.