DSLR Newb!
 

I got myself a Canon 350D from a boot fair last Sunday for £40!

Works perfectly, and came with a 35-80mm Lenses.

Closet I've ever come to using DSLR is a bridging camera, which is basically point and shoot.

I've watched a few YouTube vids, but can someone explain in simple terms AV and TV.

Thanks :wink:

Keen bird watcher are we :rofl:

AV = Aperture Priority http://www.wikihow.com/Use-Your-Came...-Priority-Mode


TV = Shutter Priority


this covers both: http://digital-photography-school.co...riority-modes/


nice camera by the way, I have an eos 20d and am looking to get a 50d or 1D mk2 or 3 soon.

AV - Aperture Value. This mode lets you control the aperture (The iris inside the lens) and takes over shutter speed and ISO for you. The wider the aperture, the more light hits the sensor and will create blurred backgrounds. The smaller the aperture, the sharper the image will be... (In general)

TV - Time Value. This lets you select the shutter speed, while sorting out the aperture and ISO for you. With a fast shutter speed, you can freeze fast motion. The slower the shutter speed, you can create movement in your photo. (For example, those photos you see of motorsport, where the car is sharp, but the background is blurred as it's blasting down a straight)

There's a lot more too it and might sound a bit boggling, but with practice you'll soon crack it! :doubleup:

Bit of a thread revival but thought I'd post up... I’m very bored at work so this might get a bit long…


In pretty much any camera, there's a lens, a shutter, and a light-sensitive photo medium i.e. film or sensor. That's it; at their heart even digital cameras are just this. To capture an image, the medium needs to get just enough light, and not too much. So there's three different values which together affect how the image is taken.

First value is aperture. This is exactly the same as the iris muscles in our eye: in bright situations we regulate the amount of light entering the eye by restricting the pupil (aperture) and the opposite happens in low-light. The camera lens has an iris which is made by a set of interlocking blades, as the angle of each blade reduces the iris opens. You’ll have a maximum aperture dictated by the lens. It’s shown by the F-number e.g. f2.8, f4.5, which is a ratio of lens length to maximum lens width basically. You can choose to stop the aperture down narrower, but of course it can’t be opened wider than maximum.

Second value is shutter speed, simply how long the shutter stays open for. With DSLRs this will usually range from something like 30secs to 1/3200th of a second or so (some slower, some faster than this).

Third value is medium sensitivity. This is referred to by the 'ISO' range: most point-and-shoot cameras won't even let you play with this setting, but DSLRs will. The lower the ISO, the less sensitive the medium is to light. It will go from around ISO 50 to ISO 3200+ with modern DSLRs. It might seem obvious to always go with the highest sensitivity (and in some situations you will need to) but the trade-off is a loss of fine detail, and increased 'noise' or grain in the image. Particularly with digital this noise can be quite unattractive, with film however less so.

Aperture affects 'depth of field'. This is best thought of as a zone of focus extending out from the camera: from the point where you focus, there will be a range in front and behind which will appear to be sharp. With a wide aperture you'll get a shallow range of focus, whereas with a narrow aperture you'll have a broad range. So it's not to say wide aperture = unsharp, just that where you focus is a bit less critical with a narrow aperture. Wide aperture is used a lot in portrait photography, where the focus is almost always on the subject's eyes: come forward and you may see that the tip of the nose is blurred in a front-on shot, likewise going back the ears won't be in focus either. But this effect is really useful, as we're drawn to see what's in focus. If you go on Speedhunters.com, you’ll see a lot of pics using wide apertures in car photography, using the selective focus to highlight beautiful / unusual aspects of the vehicles. Narrow apertures OTOH can be used to good effect in landscapes, where the depth of field will appear to come forward all the way to the viewer (or near enough), and aft go out to infinity / horizon.

Shutter affects the amount of ‘movement’ in the shot, as Hrimfaxi points out. Slow shutter speeds can be used to introduce some blur around the picture’s subject. An extreme example is that of star trails where say a mountain in the foreground is sharp, and the stars create concentric curves in the sky behind; for this the shutter is left open for hours. And yes in motorsport photography the effect is exploited too to lend an impression of speed. In the first example the camera will be mounted absolutely still on a tripod, in the second the ‘tog will need to pan the camera along with the car’s movement. Fast shutter speeds OTOH can completely freeze movement, which itself can make some nice creative effects e.g. with splashing water or whatever.

Regarding ISO sensitivity, a good rule of thumb is go for the lowest value you think you can get away with. This preserves detail and dynamic range. If you find the shot's not possible due to low light, go up one (each step doubles the sensitivity).

So all these values are present in the camera’s fully manual mode: theoretically you choose each value for every picture. However most photographers will usually have a good idea of which creative effect they wish to get, so will often only vary time or aperture, deciding on a compromise setting for the unwanted values. AV and TV takes the thinking out of it, it’s like a halfway house between point-and-shoot and fully manual. With AV selected you decide you want a certain opening for your creative effect, the camera automatically decides the shutter speed for you. Vice versa with TV.

FWIW I’d recommend shooting absolutely tons of images: with digital you’ve no processing costs so you’re completely free to mess around, make mistakes and learn. As a massive bonus, every image you take will contain EXIF data – when you see a memorable shot or a big mistake, you can right-click ‘properties’ and you’ll be able to see what the aperture, shutter and sensitivity were so you’ll know exactly how you did it.

Great post :10:

Thank you!

:grin:

I also have a new camera,what a fantastic post.Thanks Luke.

Cracking post Luke :)

There are a few budding photographers on here ;)

Really good read Luke, I was bored on my lunch break at work so made the most of it reading your post :).

I use a Nikon I got second hand from eBay, best method I have found for working out what an earth I am doing is to keep taking pics and playing with the settings, a bit of trial and error!

I think its important for people to be 'brave' and try taking photos in manual mode, I am sure there are lots of people who have some amazing cameras but they have been left on 'auto' since they were taken out the box ;-)!

Yeah I see that - I've been jealously looking through the various 'Ring Trip photos among others!

Hahaha it's amazing how 'productive' one can be when bored at work, but at least you waited for your lunch, I didn't :ninja:

Yes absolutely, experimentation is key. A good technique especially when first learning or returning to the camera is that of 'bracketing'. Essentially this involves taking three pics of the same scene, doing one at the best-guess 'correct' exposure, one slightly darker and one lighter. This way you're likely to get one that looks right on the screen / in print. But for fun you can bracket with the other parameters too - varying aperture, ISO or shutter speed up and down depending on what you're trying to achieve.

I suppose the other really big tip is to experiment with angle, position and zoom, regardless of whether you feel technically competent with the camera or not... Too many people take a pic from their eye level, hoping to convey to the viewer what they 'saw'. Two problems here. First problem is that psychology of sight is highly selective: we can often focus our minds on the interesting bits while completely ignoring the ugly / mundane. Hence seeing pics with a pylon sprouting from the person's head and similar :) Angle is everything, so experiment with getting down low, high :mrgreen: and out to the side to try to bring the view into proper context and convey what you're feeling.

Second problem is that camera lenses usually present a different view of the world to our eyes - they're usually either wider (wide-angle, 35mm or lower) or narrower with more 'reach' (telephoto, 50mm or higher). This distorts the view hugely, but can be used to great creative effect. If you have a zoom lens, experiment by taking two front-on pics of someone's face. Fill the frame with their face at the longest zoomed setting and take a pic (you may need to step back a fair way). For the second shot do the opposite, zooming right out and getting close to the subject to get their head roughly the same size in the viewfinder. If you compare the two images you're going to see a massive difference. The telephoto pic will be largely flattering, with a shallow depth of field (unless you were able to stop aperture down a lot). The wide picture on the other hand is going to make the subject look comical, with an overly-enlarged nose and small ears. You can really mess with people's expectaions of beauty with this simple technique, it's one of the ways the paps / photo editors manipulate public opinion both when celebs are on the up and on the wane. Get in close with a wide lens and you can make anyone look funny... :kicknuts: But on the flip side this really 'works' for some pics too!

It's also worth noting what you can see in the background of each shot - you'll notice that the tele shot is much more 'compressed' with a narrower view of the background. Also you'll find that what is visible in the background is made more prominent. With the wide shot, you'll see loads more in the background, but each item / feature will appear to be further away than they are. Definitely worth considering these variables when you compose a pic!

It's a key moment when a photographer realises that there is an infinite choice of camera position, angle and zoom and starts to play with these. Add good creative use of aperture and shutter speed effects, and you're definitely getting somewhere: you can vary all these simple physical aspects to convey exactly what you want. Really this is the essence of creative photography.

If you decide to write a book for budding photographers can I have a signed copie.Keep this thread going please.

Hahaha that's very flattering but it's all common knowledge really, this info is available in lots of places, especially online. When I started shooting ten years ago I'd pick up old photography books in charity shops and plunder them for useful stuff. Despite having no mention of digital stuff (and because of this too) they outline the basics of photography very well and make you concentrate on the physical aspects - getting it right 'in shot' with the correct angle, focus, filter etc.

As a result, although I've only ever shot seriously with digital, I stick to old-school darkroom techniques within Photoshop and I've got quite an old-fashioned ethic, effectively sticking with the equivalent of film choice and a limited range of post-processing techniques. But there's so much creative stuff which can be done with digital, it's a very exciting world nowadays, but as I say I'm quite traditional! There's many more useful sources than me.

As an aside, there's a good example of telephoto 'compression' or foreshortening in this thread. If you look at StevePPP's current profile pic, it's a 3/4 view of the front and offside of his car on the Karussel. Notice how, despite the New Age cars being longer and taller than classics, Steve's car has almost got classic-like dimensions in this pic. Steve's morettes contribute, but to my eyes at least, you could glance at the pic and see a well-sorted classic. Moreover, the Karussel is quite a big, wide-open place, and the 'tog will have been shooting from the far side (with a mahoosive telephoto lens, probably using a monopod to stabilise). See how there's very little background visible, and the ramps behind look massive. These effects are present in Ginola's profile pic too, with the kerbs behind the car. Both are really dramatic shots, and emphasise how telephoto shots can work really well.

There's a good wide-angle shot too in NL03Scoob's profile, compare how the blob-eye shape is presented so differently to Ginola's pic above, the choice of zoom setting makes the front of the car leap out, making the headlights and grill really prominent. In a good way it's very in-your-face and makes an interesting comparison with the other style.

Who would have thought I could spend so much time looking at other peoples profile pics! I like how you have pulled little bits from the pictures, giving explinations along with examples for Steve's and Ginolas pics along with my own.

A friend of mine who is good with cameras took the picture of my car. He set it up on a tripod and after a few practise shots and getting the correct paramaters as well as the car in focus we waited for the moment when a car drove past, behind mine. We were fortunate that the shot came out as well as it did on the first pass, the pic you see had not been editied in any way.

It's a good image, and in contrast to the other two mentioned it shows that there's no absolute correct way of taking a shot. The various profile pics all stand well on their own and were chosen for a good reason (they all 'work') but when you consider the composition and the predominant features being expressed, they're all very different :)