Understanding lenses.

I bought the 50mm 1.8 first, had fun with it for a while indoors but then when taking it for landscapes realised it wasn't feasible, I then bought the Canon 10-22mm and it's been fun, and I love how wide it is, my next purchase in the summer is going to be tricky though, I don't know whether to go for a decent walkabout lens (good range e.g the 17-70), go for a macro for some fun or a decent zoom (70-200) because whichever decision I make I'm missing out a lot of focal lengths.

It's all what you think you'll use the most, the 10-22mm (/10-20) is fun as though!
 
RandomTom said:
I bought the 50mm 1.8 first, had fun with it for a while indoors but then when taking it for landscapes realised it wasn't feasible, I then bought the Canon 10-22mm and it's been fun, and I love how wide it is, my next purchase in the summer is going to be tricky though, I don't know whether to go for a decent walkabout lens (good range e.g the 17-70), go for a macro for some fun or a decent zoom (70-200) because whichever decision I make I'm missing out a lot of focal lengths.

It's all what you think you'll use the most, the 10-22mm (/10-20) is fun as though!
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Well im interested in landscape, panoramic shots and shots of the sky mostly... Atm that is, there my fav types of photography, and i want to get shots of objects, i.e. wind farm, trees, buildings, tunnels, things that you dont see that many pics of of that no one has ever seen shots of, impressive shots.

Ill get a 18-55mm kit with my camera, what kind of shots will that favour the most?
 
You know when you turn a compact sideways to get a different type of shot i.e. landspace/portrait, can you just turn the lens instead of the camera?
 
But you can get a 'vertical grip' which attaches to the bottom of the camera, and means you can still grip it normally even when turned through 90 degrees. These usually take an extra battery too.
 
Joe T said:
But you can get a 'vertical grip' which attaches to the bottom of the camera, and means you can still grip it normally even when turned through 90 degrees. These usually take an extra battery too.
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Battery grips?

Expsnsive? What would an average or reasonable price be?
 
you can pick up an unbranded grip that's basically the same as the Canon one for about £35-36 imported from HK. Or a cheap one which just offers the grip+extended battery life rather than the extra controls for £20~.

The official one is £75-80.
 
If you understand how a lens works, you will understand what all lens do.

First off is focal length, for example "18-55mm" written on a kit lens. The human eye sees at the similar focal range and angle of view as 50mm on a digital full frame or film camera. (roughly 30mm on a 1.6x crop sensor [ i.e canon 400d ] )

So basically speaking, on a canon 400D, to zoom in double what you see, you would need to use 60mm.

Next up is aperture, for example "f/3.5-f/5.6" written on a kit lens. These are the minimum apertures at both ends of the focal range. So at 18mm the minimum aperture is f/3.5, and at 55mm the minimum aperture is f/5.6 (although f/5.6 will probably take effect at around 40mm). The lower the f/number means the faster the lens is. This is why fixed aperture lens (i.e. f/2.8) are so expensive. Aperture controls the size of the opening in a lens, effecting how much light passes through the lens to the sensor. A low aperture (i.e. f/3.5) means the hole is larger, letting more light to the sensor. A higher aperture (i.e. f/11) means the hole is smaller, letting less light to the sensor. As seen below in the diagram (image originally hosted by www.shortcourses.com)

aperturexq7.jpg


Aperture also effects depth of field (the distance infront and behind of your focal point). A low aperture will give you a small DOF, a high aperture will give you a larger DOF.

For example:

F/2.8
aperturelowuv9.jpg


f/16
aperturehighbh5.jpg


There are many abbreviations manufactures use for extra features of a lens. Most of the descriptions for these can be found on their site.
 
alexisonfire said:
If you understand how a lens works, you will understand what all lens do.
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Thats perfectly taught, i completely understand that, someone did try to teach me last night but i found it slightly difficult to comprehend but the pictures helped quite a bit.

Ill sum it up to make sure i got it right:

  • Higher the aperture, lower the light.
  • Higher the aperture, Longer the DOF

Thats right yeah?

So then... How does exposure work along with this? I understand longer the exposure slower the shutter ultimately bringing in more light, but how does that work with aperture?
 
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James07 said:
So then... How does exposure work along with this? I understand longer the exposure slower the shutter ultimately bringing in more light, but how does that work with aperture?
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You simply have to balance one with the other to get the exposure you want.

Also, remember that a large aperture = small f-number! This is something that gets people confused time and time again.
 
If you use a higher (smaller) aperture you can use a longer exposure without overexposing the shot.

For example I just took a shot at 200 ISO, f3.5 and I used 1/20s to get a correct exposure whereas f/22 gave similar results with a 2 second exposure.
 
Not quite, using a large aperture such as f/2.8 has a shallow depth of field, this aperture also is good in low light situations.

Aperture and shutter speed go hand in hand, and they often lead to a compromise.

If you're shooting in daylight you might be able to use 1/200 seconds to keep a steady shot (at say f/4), but for landscapes where you might want a lot in focus, a smaller aperture of say f/16 means that you're going to have to lower the speed to maybe 1 second to let the same amount of light in (to keep it properly exposed).
 
Shutter speed
aperture

1/4000
F2

1/2000
F2.8

1/1000
F4

1/500
F5.6

1/250
F8

1/125
F11

1/60
F16

1/30
F22

1/15
F32

1/8
F45
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Im assuming thats the settings for the perfect exposure? It was on the website provided by Gungnir.
 
Nah that's pretty much just crap. Exposure depends on the ISO as well, and the situation you are in, what you're shooting, whether you have a tripod. IMO take no notice to that at all, and when you get it, use the camera and see.

I took over 400 photos before I kept/edited one to keep. One outing I had I kept 2 out of 150 images, (I only want the best though) you'll find the right settings through just using the camera.
 
James07 said:
Im assuming thats the settings for the perfect exposure? It was on the website provided by Gungnir.
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Each of those will give the same exposure (same amount of light will hit the sensor) with the same ISO setting but the image will vary dramatically from the first to the last example. Perfect exposure is entirely dependant on the conditions and what you want to achieve.

Every time the shutter is stopped down the aperture is stopped up to balance the exposure.
 
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