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Old Oct 21, 2009, 1:08 PM   #71
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Ok - it took 70 posts and another look at last year's pictures for me to finally get it - can anyone recommend a decent, well priced dSLR
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Old Oct 21, 2009, 1:39 PM   #72
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Originally Posted by ginaflav View Post
Ok - it took 70 posts and another look at last year's pictures for me to finally get it - can anyone recommend a decent, well priced dSLR
It is the concensus of the participants in the Further questions about the Canon XSi thread that the Canon T1i (~$705 body only, or ~$785 with the kit 18-55 stabilized lens) along with any of the Canon 100mm f/2.0 (~$450) or the Sigma 70-200mm f/2.8 (~$800.) I've also mentioned the Sigma 50-150mm f/2.8 (~$650), but no one has weighed in on that suggestion yet.

What focal lengths have you shot at in the past?
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Old Oct 21, 2009, 8:44 PM   #73
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Not trying to be funny but I don't know what a focal length is. Do you mean how far from my subject? I really have never used anything more than a P&S in the past.
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Old Oct 21, 2009, 9:23 PM   #74
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Gina-

But you can learn. Or, do you prefer not to learn/ Focal length is a measurement of generally about where a lens will actually focus. You just learned that small piece of information. More can come along the very same way you learned that small fact.

Sarah Joyce
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Old Oct 21, 2009, 9:56 PM   #75
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Focal legth is the distance in mm from the optical center of the lens to the sensor or film plane. So, a 50mm lens has an actual physical distance of 50mm from the optical center back to the sensor on the camera.

The term gets confusing because people have referred to 'effective focal length' of a lens or camera. When people talk about 'effective focal length' they're trying to provide a standard for comparison. A 50mm lens on a Nikon APSC sensor cammera has an effective focal length of 75mm. What that means is the image that appears on the sensor thru a 50mm lens on that apsc sensor is the same image that would appear on a full-frame sensor using a 75mm lens. Where it is easier to see the disparity is in digicams. You'll see that a digicam may have a 480mm equivelent lens. The physical measurement is far short of 480mm. But in order to get that same image size on a full frame DSLR you would need a lens with an actual 480mm physical focal length measurement.

The above is not technically 100% correct but it's close enough in layman's terms
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Old Oct 21, 2009, 10:56 PM   #76
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Focal legth is the distance in mm from the optical center of the lens to the sensor or film plane. So, a 50mm lens has an actual physical distance of 50mm from the optical center back to the sensor on the camera.

The term gets confusing because people have referred to 'effective focal length' of a lens or camera. When people talk about 'effective focal length' they're trying to provide a standard for comparison. A 50mm lens on a Nikon APSC sensor cammera has an effective focal length of 75mm. What that means is the image that appears on the sensor thru a 50mm lens on that apsc sensor is the same image that would appear on a full-frame sensor using a 75mm lens. Where it is easier to see the disparity is in digicams. You'll see that a digicam may have a 480mm equivelent lens. The physical measurement is far short of 480mm. But in order to get that same image size on a full frame DSLR you would need a lens with an actual 480mm physical focal length measurement.

The above is not technically 100% correct but it's close enough in layman's terms
That was in layman's terms??? LOL
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Old Oct 21, 2009, 11:00 PM   #77
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Not trying to be funny but I don't know what a focal length is. Do you mean how far from my subject? I really have never used anything more than a P&S in the past.
I think he was asking if you had used longer lenses before...if you use zoom on your P&S, you are effectively changing the focal length, so think of it that way. A longer focal length is zooming you in on your subject (so you will see less of it).
The reason it is so complicated with digital cameras is because the size of the sensor varies.
I don't know if you were familiar with different film cameras? There is the 35mm SLR, but the older P&S film camera used 110 film (remember that? Or am I just old? LOL), and then there were the really cool, really expensive "medium format" cameras like the Hasselblad...all of those had different sizes of film, so you had different results with a given lens (if you could switch the lenses, that is)...it is the same idea now, only more so... Did that help? Did you check out the xsi thread?
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Old Oct 22, 2009, 3:47 AM   #78
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Quote:
Originally Posted by mtclimber View Post
Gina-

But you can learn. Or, do you prefer not to learn/ Focal length is a measurement of generally about where a lens will actually focus. You just learned that small piece of information. More can come along the very same way you learned that small fact.

Sarah Joyce
Hi Sarah, sorry to say this is not at all correct.
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Old Oct 22, 2009, 4:02 AM   #79
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Not trying to be funny but I don't know what a focal length is. Do you mean how far from my subject? I really have never used anything more than a P&S in the past.
This will give you some examples of how a the field of view changes with the focal length of a lens.

http://www.usa.canon.com/app/html/EF...al_length.html

If you get a spare minute and want to get a little more technical then you can take a look at this http://www.photoxels.com/tutorial_focal_length.html
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Old Oct 22, 2009, 4:54 AM   #80
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Here's an explanation of focal length:

http://en.wikipedia.org/wiki/Focal_l...In_photography

And here's another website that demonstrates the effect of focal length on angle of view:

http://www.tamron.com/lenses/learnin...comparison.php
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