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Jul
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      03-07-2005, 01:39 AM
hi,

Specification for Canon G5 says that lens 7.2 - 28.8 (35 mm equivalent 35 -
140)
The ratio at both cases 1:4
but why 7.2 equivalent 35 (not 30 or 40) ?
does 7.2 for any model equivalent 35?
if not how to know what number equivalent 35 mm?

and what does mean 1:2.0 - 3.0?
all of these numbers on the lens

Thanks.


 
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[BnH]
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      03-07-2005, 02:40 AM
Canon G5 .. .as you typed :

7.2 -> 28.8 mm [ this is the 1:4 ratio .... == 4x zoom ] on 35mm range ..
it covers 35-140mm range.

f/ 2.0 -> 3.0 the max aperture at wide end is 2.0 and at the tele end is
3.0.

=bob=

"Jul" <(E-Mail Removed)> wrote in message
news:fhOWd.2549$(E-Mail Removed).. .
> hi,
>
> Specification for Canon G5 says that lens 7.2 - 28.8 (35 mm equivalent
> 35 - 140)
> The ratio at both cases 1:4
> but why 7.2 equivalent 35 (not 30 or 40) ?
> does 7.2 for any model equivalent 35?
> if not how to know what number equivalent 35 mm?
>
> and what does mean 1:2.0 - 3.0?
> all of these numbers on the lens
>
> Thanks.
>



 
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Don Stauffer in Minneapolis
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      03-07-2005, 03:19 PM
Jul wrote:

> hi,
>
> Specification for Canon G5 says that lens 7.2 - 28.8 (35 mm equivalent 35 -
> 140)
> The ratio at both cases 1:4
> but why 7.2 equivalent 35 (not 30 or 40) ?
> does 7.2 for any model equivalent 35?
> if not how to know what number equivalent 35 mm?
>
> and what does mean 1:2.0 - 3.0?
> all of these numbers on the lens
>
> Thanks.
>
>

The 35 mm equivalent is used to refer to a film camera using 35mm film.
Many digital camera users are ones who had used 35mm in past. These
folks had acquired a feel for the field of view, or perspective, of a
given focal length on their 35mm camera. I myself am in that category.
If the ad says the digicam has an 8mm - 24mm range of actual focal
length, I must find the chip size and do some math to see what actual
field of view the lens covers. If they say it is a 30-90 mm 35mm
equivalent, I know it goes from moderate wide angle to moderate telephoto.
 
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