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Old May 13, 2007, 1:14 AM   #21
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i was looking through the canon lenses section and found a discussion about telezoom lenses. would the Sigma 70-300 APO DG Macro be long enough for my shooting situation. It seems liek a gr8 lens, and a nice low price tag. My other issue is that the cannon Xt (i dont think) has image stabilization, and i think cannon puts the stabilization into their lenses. So if im holding the camera w/ my hands and i shake a littl while rpessing the button, would the picture get messed up?
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Old May 13, 2007, 1:25 AM   #22
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i looked on other forums and i found that pople bought a 70-300mm lens, then bought a "1.4x" which turned it into a 520mm lens. I dont really understand what a 1.4x is but it seems like an attachment that magnifies the lens. Would this help me afford a 400mm lens for my budget?
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Old May 13, 2007, 2:09 AM   #23
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You probably are not going to be able to use a typical 70-300mm lens like at all in lighting that low, much less with a Teleconverter. You lose too much light (a 1.4x TC will result in one stop of light loss, which means only half the light gets to the camera). That means you'd need shutter speeds twice as long for proper exposure for any given lighting and ISO speed. That means blurry photos. ;-) Most cameras won't even be able to Autofocus if you tried to use a teleconverter on a lens as dim as the ones you're looking at (the typical 70-300mm zoom lenses only have f/5.6 available).

You've got to worry about the shutter speed you'll be able to get with any lens you consider, and that means having a good understanding of what aperture and ISO speed you'll need available to the camera.

That's why you only got 1 photo out of 150 that was sharp (your shutter speed was very slow). ;-)

That's a very good shot. But, the shutter speed was only 1/10 second at f/3.7.

f/3.7 is more than twice as bright as the largest available aperture on the zoom lenses you're looking at (the ones you're looking at are only f/5.6 on their long end, which lets in less than half the light of your Kodak's lens at f/3.7). That means even *slower* shutter speeds for the same lighting and ISO speed with the lenses you're considering ;-) But, a DSLR does have higher available ISO speeds (which is how sensitive the camera is to light).

Do you know what ISO speed was used for that photo? The Flikr Account you are using stripped out the EXIF from the image. It shows the EXIF under properties in flikr. But, it does not give the ISO speed.

I'm trying to see what you may be able to get for shutter speeds with a DSLR at much higher ISO speeds. But, I would not count on being able to use the types of lenses you're looking at. They're probably not going to be bright enough for indoor photos without a flash.

Otherwise, you're going to get blur from both camera shake and subject movement. You can eliminate blur from camera shake by using a tripod (or using a technique like you did and place the camera on something sturdy and use a self timer). But, that will not help if the subject is moving any at all. You'll need a perfectly still subject to get any non-blurry photos that are usable at smaller print sizes at shutter speeds that slow.

In order to get a better idea of what you would need, I need to know the ISO speed that photo was taken at. Can you post a downsized copy of it here (or from some other source besides flikr)? Flikr stripped the EXIF from the images you can see, and it's Photo Properties section showing EXIF info is incomplete.

Chances are, you're going to need a lens with f/2.8 or larger apertures available (and smaller f/stop numbers represent a larger aperture opening) to have much chance at usable images if the light is as low as I suspect it is. The lenses you're looking at are nowhere near that bright.

I see you used both Photoshop CS2 and Picasa to edit that image. Can you take a look at the image properties in one of them and see what ISO speed was used?

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Old May 13, 2007, 2:42 AM   #24
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P.S.

With an entry level DSLR model like the Canon you're looking at, a lens will appear to be about 60% longer.

For example, a 300mm lens on an entry level Canon DSLR model would give you the same angle of view (apparent magnifcation) that you'd get using a 450mm lens.

The shot you took was equivalent to the same angle of view you'd have using a 380mm lens on a 35mm camera. So, you'd need a focal length of around 240mm on a DSLR to get the same framing (because a lens on an entry level model like the Canon you're looking at will appear to be about 60% longer since the sensor is smaller than 35mm film).

But, lenses that long are probably not going to be bright enough to get many usable images, unless you're willing to spend a *lot* more money than you have budgeted.

My guess is that you're going to need to go with a used lens (something like a Sigma 70-200mm f/2.8 ) and crop for the desired framing, in order to get fast enough shutter speeds to get some keepers and stay within budget. A better choice would be something like a Sigma 120-300mm f/2.8 (but, that lens sells for around $2700 at online discounters). A bright lens that long is not cheap, and you need a bright lens to get enough light to the camera to get faster shutter speeds indoors without a flash. Otherwise, you'll end up with blurry photos.

With your budget, you may have to go with a slower lens. But, I would try to avoid the consumer grade lenses with only f/5.6 available, or you may be in worse shape than you are now.

Let's figure out what ISO speed you were shooting at first. That will tell us more about what you can expect with a given camera/lens combination, and we can suggest a few options. Also, would you be permitted to use a external flash at these speaking engagements?


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Old May 13, 2007, 9:07 AM   #25
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I have tried everything, including a special exif reader to find the iso of my images, but it seems that if my camera used the "auto" setting for the iso, it doesnt record it in exif. I looked at many other pictures that i took, and the exif shows everythihng but the iso. So i cant figure it out. what should i get? And i cant use a flash during the speech
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Old May 13, 2007, 9:28 AM   #26
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Arfi wrote:
Quote:
i was looking through the canon lenses section and found a discussion about telezoom lenses. would the Sigma 70-300 APO DG Macro be long enough for my shooting situation. It seems liek a gr8 lens, and a nice low price tag.
Yes. After rereading some of the reviews of the different lenses I mentioned, it seems to me that the Sigma and the Tamron are the best choices.

Arfi wrote:
Quote:
My other issue is that the cannon Xt (i dont think) has image stabilization, and i think cannon puts the stabilization into their lenses. So if im holding the camera w/ my hands and i shake a littl while rpessing the button, would the picture get messed up?
Canon has Image Stabilization, but only in certain lenses. (Pentax and Sony dSLRshave it in the camera body.) But it seems to me that you have the luxury of having a table that you can brace yourself on, or even mount a small tripod on, as you take the picture, so you should be able to prevent camera shake easily. In addition, unlike your old P&S, a dSLR will have higher ISO settings and brighter lenses that you can use, so you can use faster shutter speeds to eliminate the effects of camera shake.

In addition, someone (I think it was JimC) expressed concern about exposure, but it seems to me that if you were able to get good quality images from your P&S, switching to a dSLR will only make the situation better, for some of the same reasons that permit you not to be too concerned about camera shake.
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Old May 13, 2007, 9:33 AM   #27
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A teleconverter multiplies the focal length of the lens mounted on it. Teleconverters are good ina pinch, but they add optical elements to the camera, and so reduce sharpness and add distortion and other nasty bits, so they are not something you should use routinely. Also, they reduce the brightness of the lens and make autofocusing more difficult.

So, for your routine shots, I think you should avoid teleconverters.
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Old May 13, 2007, 9:39 AM   #28
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So what lenses should i get for normal use, hobby use, and the speaker situation(i know u posted the speaker lenses before..ill look those over. Whata bout the toehr lenses? Also what ype of flash would be good (for when i go into small scale wedding photography
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Old May 13, 2007, 11:44 AM   #29
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In addition, someone (I think it was JimC) expressed concern about exposure, but it seems to me that if you were able to get good quality images from your P&S, switching to a dSLR will only make the situation better, for some of the same reasons that permit you not to be too concerned about camera shake.
He said that only 1 out of 150 photos was not blurry, using a table and self timer to get that one.

That's not very good odds, and the photo he posted a link to was taken at 1/10 second and f/3.7 using Auto ISO on a model that goes up to ISO 800 if you set it manually.

Any subject movement at all and you're going to get motion blur at 1/10 second, even if you use a tripod, especially for a head and shoulders type shot, since any movement will occur over a greater percentage of the frame compared to a wider shot.

Now, the question in my mind was the ISO speed the camera was actually using with Auto ISO. It appears that it's not being recorded in the EXIF from the photos that the OP as looked at.

My guess (only a guess) is that it's probably around ISO 320. That's typical for Auto ISO on an older 4MP model like that with up to ISO 800 settable manually.

So, if he went with a consumer grade lens with only f/5.6 available, he'd be at around 1/15 second at ISO 1600 in the same conditions (his current lens is more than a stop brighter at longer focal lengths). That's not going to "cut it" if you want many keepers, even using a tripod, for head and shoulders type shots of someone speaking (unless they're made of stone). lol

I'd suggest a lens that's at least a stop brighter, and preferraly two stops (or more) brighter.
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Old May 13, 2007, 11:55 AM   #30
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any suggestions? (i was gonna say that i remeber the camera saying it was at iso 320. I wasnt sure though, i could of been making it up. It was just a picture ni my mind. So i would say 90% it was at iso 320). The cannon kit comes w/ a 18-55mm lens. If theoretically i would get a 75-300mm, then is there any cheap lens that would cover 55-75mm? or i could just buy the body and get like a 17-75, if they exist. I dont know good brands or any lens. Suggestions would be gr8. I have to order my camera today

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