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Old 09-30-09, 12:23 PM   #16
Von Hinten
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Thanks a bunch John, that's great info.

I'll start shooting questions then: that buffer running full, does it empty itself after not taking shots for a few minutes/seconds? Or how else do you get the camera back up to speed again?

And what does 'low F is 3.5 quickly moves to 5.6' and 'Light 'sensitive with F2.8' mean? I guess I just need to know what the 'F' stands for.

With regard to the lenses I think I read that you suggest sticking with the default lens until I grow out of it. Oh, and not get a Canon L series until I know for 110% sure that the reason the picture wasn't what I needed it to was not my own fault. Check.
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Old 09-30-09, 12:51 PM   #17
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I'm going to disagree slightly with McBeck's explanation of Canon's lens range.
Canon has a very wide range of lenses, with plenty in-between the budget lenses and the L-series lenses. In my experience, there are usually three choices with Canon lenses; budget, medium, and L-series.

The budget lenses are very cheap, but still produce good quality images if you understand the limitations of the lens. Usually they will have small maximum apertures (f/4 to f/5.6) and slower focusing (the old arc-form drive or micro-motor focusing). Examples: EF 50mm f/1.8 II, EF-S 55-250mm f/3.5-5.6 IS.

The next step-up usually gives faster focusing (using either of Canon's USM focus motors), but keeps the small apertures. Historically it also added things like IS to the lens, but that is now found on budget lenses too. Examples: EF 50mm f/1.4 USM, EF 70-300mm f/3.5-5.6 IS USM.

The top of the range are the L-series, which give optimum optical quality, large apertures (f/1.2 for primes, constant f/2.8 for zooms) and very rugged build quality. You also get the full ring-USM focusing in most (all?) cases. Examples: EF 50mm f/1.4L USM, EF 70-200 f/2.8L IS USM.

The kit-lens which comes with the 450D is fine, as long as you accept that it's slow to focus and won't be very good for low-light photography. If you primarily shoot landscapes, it's fine. It's only when you need to do something your current lens doesn't do that you should upgrade.

I've had a 400D for a couple of years now, and I'm reasonably happy with it. The new 7D would be ideal for me, but I can't justify the cost yet.

The buffer will fill up if the camera is capturing data faster than it can be written to the memory card. At that point, the camera will stop taking photos until enough of the buffer has been dumped to the card that it can fit in one more photo. On my 400D in RAW with a Sandisk Extreme III CF card, I can shoot 9 images in a burst before the buffer fills up. At that point, it starts taking shots about once every 2 seconds. It's a good 20 seconds or so before the buffer is completely empty again.

The f/# number you see on lens descriptions is the maximum aperture of the lens. It's the size of the hole through which the light travels to the sensor. A larger hole means more light, and a shallower depth of field. Smaller f/ numbers are larger apertures. If you see a lens specified like EF-S 18-55mm f/3.5-5.6 IS, that means that it's f/3.5 at 18mm which changes to f/5.6 at 55mm. If you zoom to, say, 30mm, you'll probably get f/4. You can always choose a smaller aperture (f/8, f/11, etc...) if you want, but those will be the largest you can get with that lens.

Hopefully that explains some of it
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Old 09-30-09, 12:53 PM   #18
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Quote:
Originally Posted by Von Hinten View Post
Thanks a bunch John, that's great info.

I'll start shooting questions then: that buffer running full, does it empty itself after not taking shots for a few minutes/seconds? Or how else do you get the camera back up to speed again?

And what does 'low F is 3.5 quickly moves to 5.6' and 'Light 'sensitive with F2.8' mean? I guess I just need to know what the 'F' stands for.

With regard to the lenses I think I read that you suggest sticking with the default lens until I grow out of it. Oh, and not get a Canon L series until I know for 110% sure that the reason the picture wasn't what I needed it to was not my own fault. Check.
OK.

F number refers to the apeture. Its the size of the whole the lens makes to the senor in the camerabody.
http://en.wikipedia.org/wiki/Aperture

A small hole will let in little light, but give you great depth of field(DOF).
Thats a high F number. See pic below:
http://fc01.deviantart.com/fs47/o/20...4e41d110fa.jpg

A big hole will let in alot of light, but give you a short DOF.
Thats a low F number. See pic below:
http://fc07.deviantart.com/fs49/o/20...15057501ba.jpg

So if you apply that to what I wrote it means that a lens which has 5.6 as the lowest F number, it means that its not light sensitive.

So why is it important how much light is let in?
In order for the sensor to capture a photo it needs a certain amount of light. How much light it gets depends on 3 things:
1) Aperture
2) Shutterspeed (How long the sensor receives light from the lens. If the speed is too slow you will get camera shake and thus blurry picures)
3) ISO (How sensitive the sensor is. The more sensitive it needs to be, the more noise it will generate - Low is better)

This pic was taken with a shutterspeed of 30 seconds (on a tripod):
http://farm4.static.flickr.com/3625/...cb1903a2_b.jpg

This pic was taken with a shutterspeed of 1/200 of a second:
http://farm4.static.flickr.com/3458/...b3992586_b.jpg

The lens I use can go from 2.8-22 through the entire zoom range. It does not matter if im at 18mm or 50mm.
The kit lens starts at 3.5 at 18mm, but you only need to zoom a little bit and it will go to 4.5 as the lowest F.

In regards to the buffer. Its inside the camera and its a fast memory thats used to store data untill its transfered to the mem card. The buffer will continue to be emptied into the mem card, but in the XXXD series the mem interface cant keep up with the buffer. The slowdown will only be for some seconds untill the buffer data is moved to the mem card.

As far as lenses I would suggest you think hard about what you need. Some people can live with the kit lens for some time.
I went straight for the Sigma lens, because I knew I would be limited too much by the kit lens.

What will you use the camera for? What scenarios?

Have you looked at my portfolio?
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Old 09-30-09, 01:08 PM   #19
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Quote:
Originally Posted by Prof View Post
I'm going to disagree slightly with McBeck's explanation of Canon's lens range.
Canon has a very wide range of lenses, with plenty in-between the budget lenses and the L-series lenses. In my experience, there are usually three choices with Canon lenses; budget, medium, and L-series.

The budget lenses are very cheap, but still produce good quality images if you understand the limitations of the lens. Usually they will have small maximum apertures (f/4 to f/5.6) and slower focusing (the old arc-form drive or micro-motor focusing). Examples: EF 50mm f/1.8 II, EF-S 55-250mm f/3.5-5.6 IS.

The next step-up usually gives faster focusing (using either of Canon's USM focus motors), but keeps the small apertures. Historically it also added things like IS to the lens, but that is now found on budget lenses too. Examples: EF 50mm f/1.4 USM, EF 70-300mm f/3.5-5.6 IS USM.

The top of the range are the L-series, which give optimum optical quality, large apertures (f/1.2 for primes, constant f/2.8 for zooms) and very rugged build quality. You also get the full ring-USM focusing in most (all?) cases. Examples: EF 50mm f/1.4L USM, EF 70-200 f/2.8L IS USM.

The kit-lens which comes with the 450D is fine, as long as you accept that it's slow to focus and won't be very good for low-light photography. If you primarily shoot landscapes, it's fine. It's only when you need to do something your current lens doesn't do that you should upgrade.

I've had a 400D for a couple of years now, and I'm reasonably happy with it. The new 7D would be ideal for me, but I can't justify the cost yet.

The buffer will fill up if the camera is capturing data faster than it can be written to the memory card. At that point, the camera will stop taking photos until enough of the buffer has been dumped to the card that it can fit in one more photo. On my 400D in RAW with a Sandisk Extreme III CF card, I can shoot 9 images in a burst before the buffer fills up. At that point, it starts taking shots about once every 2 seconds. It's a good 20 seconds or so before the buffer is completely empty again.

The f/# number you see on lens descriptions is the maximum aperture of the lens. It's the size of the hole through which the light travels to the sensor. A larger hole means more light, and a shallower depth of field. Smaller f/ numbers are larger apertures. If you see a lens specified like EF-S 18-55mm f/3.5-5.6 IS, that means that it's f/3.5 at 18mm which changes to f/5.6 at 55mm. If you zoom to, say, 30mm, you'll probably get f/4. You can always choose a smaller aperture (f/8, f/11, etc...) if you want, but those will be the largest you can get with that lens.

Hopefully that explains some of it
Good comments too. I have though not found any canon lenses (yet) in the mid range that can match the Sigma 18-50 F2.8 or 70-200 F2.8.
Have you? I can only find canon lenses thats either 3.5-5.6 or highend(L)
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Old 10-01-09, 03:55 PM   #20
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Nikon Coolpix P90.

http://imaging.nikon.com/products/im.../p90/index.htm
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Old 10-01-09, 05:01 PM   #21
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Okay, I'm going to give a slightly less technical answer here... and a bit provocative.

The real camera resides inbetween your ears, meaning that if what you see with your eyes cannot produce a good photo with just about any equipment, you may have in your hands, you're lost.

I remember I once saw a documentary about a fashion photographer, and when the model saw that he was using a small compact camera, she thought he was teasing her, but THAT was his work camera. And he did make some good shots of her.

So the most expensive camera is not necessarily what will make you happy. Decide how much money you're willing or capable to pay, and then research which options you have.
I'm happy with my Sony DSLR camera, but sometimes it's too big to bring for example going to a party, so I just use my phone camera, which is good enough for that purpose.

Now you said fast moving objects, and like others allready pointed out: a digital SLR where you have the option of exchanging the lenses.
IMHO the manufacturer name ain't the most important. If you have the option then try a photo store and ask for permission to try out some different cameras with different lenses. Ultimately, you will have to make the decision, which camera it's going to be anyhow...

Most great manufacturs have a variety of extra lenses to purchase afterwards. Check those options first. The kit lenses which you can buy together with the camera house may not be the prime lenses, but they do work as a start, and you can then slowly expand the equipment with extra lenses over time. A good lens provides a big aperture (low number like 1.8), kit lenses are often at 3.5 to 5.6 for a 24-70mm zoom. If the focal length is fixed to something like 100mm, it works better with the light available, and the lens is as such then faster working.
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Old 10-01-09, 05:09 PM   #22
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Quote:
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Ditto, a good camera lots of functions and not too bad on the pocket,
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Old 10-04-09, 04:03 PM   #23
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Yeah, I've already kind of, as good as, decided that a DSLR will be the way to go for me and am currently trying to determine on how much it can cost me. With what I've read here and elsewhere on the net it's very likely that I'll end up with the 450 but who knows. I can be a bit indecisive with things like these.
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Old 10-05-09, 01:56 AM   #24
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Quote:
Originally Posted by Von Hinten View Post
Yeah, I've already kind of, as good as, decided that a DSLR will be the way to go for me and am currently trying to determine on how much it can cost me. With what I've read here and elsewhere on the net it's very likely that I'll end up with the 450 but who knows. I can be a bit indecisive with things like these.
I hope you figure out what is the best solution. And Lars has a point. You can take great pictures with a P&S. Just remember that they have some shortcommings.
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Old 10-05-09, 06:19 AM   #25
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Check out www.dpreview.com

Its has tons of reviews and a forum where the questions have been discussed several times
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Old 10-06-09, 12:08 PM   #26
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Thanks!

Note to self: do more reading!
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