Velocity Reviews > If I Cropped A Photo From A 5D...

# If I Cropped A Photo From A 5D...

Mike
Guest
Posts: n/a

 06-28-2006
I never was any good at maths.

If I cropped a photo from a 5D to match a 1.6 crop sensor size, how many
megapixels would the image be?

5D Sensor Size = 36 x 24 mm
5D Resolution = 4368 x 2912

20D Sensor Size = 22.5 x 15.0 mm
20D Resolution = 3504 x 2336

Daniel Silevitch
Guest
Posts: n/a

 06-28-2006
On Wed, 28 Jun 2006 21:01:29 +0100, Mike <(E-Mail Removed)> wrote:
> I never was any good at maths.
>
> If I cropped a photo from a 5D to match a 1.6 crop sensor size, how many
> megapixels would the image be?
>
> 5D Sensor Size = 36 x 24 mm
> 5D Resolution = 4368 x 2912

cropped 5D: (4368/1.6)*(2912/1.6) = 4,968,600
or roughly 5 megapixels.

-dms

Prometheus
Guest
Posts: n/a

 06-28-2006
In article <(E-Mail Removed)>, Mike
<(E-Mail Removed)> writes
>I never was any good at maths.
>
>If I cropped a photo from a 5D to match a 1.6 crop sensor size, how many
>megapixels would the image be?
>
>5D Sensor Size = 36 x 24 mm
>5D Resolution = 4368 x 2912

>20D Sensor Size = 22.5 x 15.0 mm
>20D Resolution = 3504 x 2336

(4368/1.6) * (2912/1.6) = 4,968,600

3504 * 2336 = 8,185,344
--
Ian G8ILZ

Mike
Guest
Posts: n/a

 06-28-2006
Cheers Daniel

"Daniel Silevitch" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed).. .
> On Wed, 28 Jun 2006 21:01:29 +0100, Mike <(E-Mail Removed)> wrote:
>> I never was any good at maths.
>>
>> If I cropped a photo from a 5D to match a 1.6 crop sensor size, how many
>> megapixels would the image be?
>>
>> 5D Sensor Size = 36 x 24 mm
>> 5D Resolution = 4368 x 2912

>
> cropped 5D: (4368/1.6)*(2912/1.6) = 4,968,600
> or roughly 5 megapixels.
>
> -dms
>

boozz
Guest
Posts: n/a

 06-29-2006

Mike wrote:
> I never was any good at maths.
>
> If I cropped a photo from a 5D to match a 1.6 crop sensor size, how many
> megapixels would the image be?
>
> 5D Sensor Size = 36 x 24 mm
> 5D Resolution = 4368 x 2912
>
> 20D Sensor Size = 22.5 x 15.0 mm
> 20D Resolution = 3504 x 2336

David J. Littleboy
Guest
Posts: n/a

 06-29-2006

"Mike" <(E-Mail Removed)> wrote:
>I never was any good at maths.

The only difficulty is that people sometimes forget to divide by 1.6 in
_both_ directions.

> If I cropped a photo from a 5D to match a 1.6 crop sensor size, how many
> megapixels would the image be?
>
> 5D Sensor Size = 36 x 24 mm
> 5D Resolution = 4368 x 2912
>
> 20D Sensor Size = 22.5 x 15.0 mm
> 20D Resolution = 3504 x 2336

1.6x cropped 5D resolution = (4368/1.6) x (2912/1.6) = 2730 x 1822 = 4.9 MP.

Since the 5D pixels are quite a bit larger than 20D pixels, if you use the
same area of sensor from the 5D as you use on the 20D, you get a lot fewer
pixels.

In other words, if most of your shooting is birds with long lenses
(especially if you crop most of your shots), you really don't want a 5D.

The only exception would be if you really wanted more pixels on the birds
(to make larger prints) and were willing to use much bigger glass. But most
birders, I'd think, would be using the largest lenses they can afford...

David J. Littleboy
Tokyo, Japan

Roy G
Guest
Posts: n/a

 06-29-2006
"Mike" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
>I never was any good at maths.
>
> If I cropped a photo from a 5D to match a 1.6 crop sensor size, how many
> megapixels would the image be?
>
> 5D Sensor Size = 36 x 24 mm
> 5D Resolution = 4368 x 2912
>
> 20D Sensor Size = 22.5 x 15.0 mm
> 20D Resolution = 3504 x 2336
>
>

Hi.

You should have paid a bit more attention at school, if you really cannot
work out this answer for yourself.

There is quite a lot of Arithmetic involved in Photography, and in every day
life. You might well be paying too much for things you buy, or not getting
paid enough for the work you do, or even worse paying too much in taxes.

If you came to stay at my Guesthouse for 10 nights, and I said that my
special offer of "7 Nights for the price of 6" would be applied, would you
know whether I charged the correct amount. Perhaps I should do you a
special offer of "6 for the price of 7"

Roy G

John McWilliams
Guest
Posts: n/a

 06-29-2006
On 6/29/06 6:33 AM, Roy G posted the following:
>
> If you came to stay at my Guesthouse for 10 nights, and I said that my
> special offer of "7 Nights for the price of 6" would be applied, would you
> know whether I charged the correct amount. Perhaps I should do you a
> special offer of "6 for the price of 7"
>

I'd be especially wary of how the remaining 3 -or 4 - nights were
charged! Would they be charged reg. rates, or 6/7ths, or 7/6ths??
Enquiring minds and all.

--
john mcwilliams

Roy G
Guest
Posts: n/a

 06-29-2006
"John McWilliams" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On 6/29/06 6:33 AM, Roy G posted the following:
>>
>> If you came to stay at my Guesthouse for 10 nights, and I said that my
>> special offer of "7 Nights for the price of 6" would be applied, would
>> you know whether I charged the correct amount. Perhaps I should do you a
>> special offer of "6 for the price of 7"
>>

> I'd be especially wary of how the remaining 3 -or 4 - nights were charged!
> Would they be charged reg. rates, or 6/7ths, or 7/6ths?? Enquiring minds
> and all.
>
> --
> john mcwilliams

Ah, but you are not the arithmetically challenged poster who could not work
out how many pixels.

If the booking were to be initiated through this NG, you might well get an
even better deal.

But then again..............................

Roy G

Matt Ion
Guest
Posts: n/a

 06-29-2006
Roy G wrote:
> "Mike" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
>
>>I never was any good at maths.
>>
>>If I cropped a photo from a 5D to match a 1.6 crop sensor size, how many
>>megapixels would the image be?
>>
>>5D Sensor Size = 36 x 24 mm
>>5D Resolution = 4368 x 2912
>>
>>20D Sensor Size = 22.5 x 15.0 mm
>>20D Resolution = 3504 x 2336
>>
>>

>
> Hi.
>
> You should have paid a bit more attention at school, if you really cannot
> work out this answer for yourself.
>
> There is quite a lot of Arithmetic involved in Photography, and in every day
> life. You might well be paying too much for things you buy, or not getting
> paid enough for the work you do, or even worse paying too much in taxes.

Maybe the math itself isn't the problem... everyone else who's responded
seems to have a grasp on how to work their calculators, but my
understanding was that the "crop factor" figure referred to the effectiv
35mm focal length; ie. a 200mm lens on a 1.6 "crop factor" sensor would
be equivalent to a (200*1.6) or 320mm lens on a 35mm sensor; on a 1.5
"crop factor" sensor, it would be (200*1.5)=300mm.

If that is in fact the case, then all the other calculations provided
thus far are wrong...