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Old Jun 9, 2005, 7:13 AM   #1
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how truth is this quote?

Quote:
The ef 75-300mm was bought as part of a kit a Canon 500n 35mm camera + ef 28-80 + ef 75-300mm so lens was made for a 35mm film camera .

The size of 35mm film is 36mm width and 24mm height.

The sensor size in the Rebel 22.7mm w X 15.1mm h.

The image senor size in Rebel XT 22.2mm w X 14.8mm h
(Note sensor is smaller than the Rebel).

Right here we go the ef 75-300mm lens for the sake of easy counting can reproduce 100 lines per mm so on a 35mm film the image is 36 X 100 and 24 X 100 35mm image equals 3600 X 2400 good quality.

Take the same lens put it on the Rebel it cannot give you any more detail than 100 lines per mm
sensor size is 22.7 X 100 and 15.1 X 100 the image size 2270 X 1510 this about 4 million pixels
but the final image from the Rebel is 3072 x 2048 in size 6 million pixels
Only 4 going in 6 coming out

Do the same for the Rebel XT 22.2 X 100 and 14.8 X 100
2220 X 1480 image produced by lens still 4 million
final image Rebel XT 3456 x 2304 4 million in 8 million coming out it just interpolates the image that's a fancy word for guessed and made it up to 8 million.

The lens to match the Rebel it would have to reproduce 135 lines per mm
and the Rebel XT 155 lines per mm and that why I didn't buy the Rebel XT needs very good lenses which are very expensive.

Which lens all of the ones with L in it
Canon EF 28-300mm f/3.5-5.6 L
Canon EF 300mm 300 f4 L
Canon EF 300mm f/2.8 f2.8 L
to name but a few from the range.
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Old Jun 9, 2005, 8:51 AM   #2
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Its all rubbish.
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Old Jun 9, 2005, 9:05 AM   #3
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I agree with LBoy.

From your lens choices:
I've never seen the 28-300 L
The two 300 L primes are both excellent.

Quote:
Which lens all of the ones with L in it
Canon EF 28-300mm f/3.5-5.6 L
Canon EF 300mm 300 f4 L
Canon EF 300mm f/2.8 f2.8 L
to name but a few from the range."
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Old Jun 9, 2005, 11:16 AM   #4
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Actually he said that those lenses works fine with the 350D, but the other lens won´t.

I hope this to be BullS%"T too.

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Old Jun 10, 2005, 4:15 AM   #5
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The quote as it stands is silly, but it is the case that the high pixel density of cameras like the XT/20D does place higher demands in terms of resolution than most EF lenses were originally designed for.

If you think about the fact that the image is cropped to use the centre only and then "enlarged" you can see that clearly to get the same resolution you need better lenses. The crop factor is offset somewhat by the fact that you are only using the best part of the image.

As far as I can tell (and forgive me for not digging up all the links) you will get comparitively poorer resolution in the centre but better at the edges i.e. more consistent performance across the frame by using an EF lens on the XT than you would by using it on a FF35mm sensor e.g. 1Ds (MkII) but because of the 1.6 crop you have a larger COC and therefore will be requiring greater resolution from it.

If this starts a massive dispute I'm sure I can dig up the technical stuff. :-)

But all EF lenses will work on the XT.
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Old Jun 10, 2005, 7:48 AM   #6
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Im kinda énter in panic... if you got more information about this subject please let me know

Thanks

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Old Jun 10, 2005, 9:33 AM   #7
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Don't panic and don't worry about it.

Just use any EF lenses you have. As for new lenses just buy the best ones you can - as you would have in any event.

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Old Jun 12, 2005, 1:11 AM   #8
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Is this even English?? Don't pay attention to this gibberish... Paripatetic said all you need to know. The Rebel XT (and the original Rebel, and the 20D) are all compatible with all Canon EF and EF-S type lenses.

SinRastro wrote:
Quote:
how truth is this quote?

Quote:
The ef 75-300mm was bought as part of a kit a Canon 500n 35mm camera + ef 28-80 + ef 75-300mm so lens was made for a 35mm film camera .

The size of 35mm film is 36mm width and 24mm height.

The sensor size in the Rebel 22.7mm w X 15.1mm h.

The image senor size in Rebel XT 22.2mm w X 14.8mm h
(Note sensor is smaller than the Rebel).

Right here we go the ef 75-300mm lens for the sake of easy counting can reproduce 100 lines per mm so on a 35mm film the image is 36 X 100 and 24 X 100 35mm image equals 3600 X 2400 good quality.

Take the same lens put it on the Rebel it cannot give you any more detail than 100 lines per mm
sensor size is 22.7 X 100 and 15.1 X 100 the image size 2270 X 1510 this about 4 million pixels
but the final image from the Rebel is 3072 x 2048 in size 6 million pixels
Only 4 going in 6 coming out

Do the same for the Rebel XT 22.2 X 100 and 14.8 X 100
2220 X 1480 image produced by lens still 4 million
final image Rebel XT 3456 x 2304 4 million in 8 million coming out it just interpolates the image that's a fancy word for guessed and made it up to 8 million.

The lens to match the Rebel it would have to reproduce 135 lines per mm
and the Rebel XT 155 lines per mm and that why I didn't buy the Rebel XT needs very good lenses which are very expensive.

Which lens all of the ones with L in it
Canon EF 28-300mm f/3.5-5.6 L
Canon EF 300mm 300 f4 L
Canon EF 300mm f/2.8 f2.8 L
to name but a few from the range.
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