[matthewwong]

Crop cam is it mean like 500D 50D 7D??
FF is it mean 5D, 1D?
I'm not so sure....
by the way, I saw u guys written crop cam use 24-105 is not wide enough....need to use FF??
Can u guys explain it to me??
THX CHING

[h0001244]

crop size sensor is smaller than FF sensor
Aps-c is only 40% of FF
The same focal length eg 24mm on APS-c looks like zoom-in compared with FF
To make it easy to understand, we add a multiplier factor to the focal length.
APS-C on Canon is 1.6x
ie. 24mm on APS-c = 24mm x 1.6 on FF = 38.4mm on FF
note that physically no change on focal length, but just to let ppl who used to the FF or 135 system easier to make reference to it

Exact expression shall be, angle of view of 24mm on APS-c = angle of view of 38.4mm on FF

[ACanonGuy]

Hi Matthew,

Here is a good reference for your question.

http://www.the-digital-picture.com/Canon-Lenses/Field-of-View-Crop-Factor.aspx

With 24mm on FF you get an angle of view of 84 degrees which is considered "wide angle". With the same 24mm on 1.6x crop factor sensor body such as the 7D it becomes 24mm * 1.6 roughly = 38mm in which the angle of view will be less than 84 degrees and may fall under the "wide angle" threshold of about 70 degrees (?).

Hope this helps.

[happyt610]

I would recommend you to read this link before buying any DSLR
http://web.canon.jp/imaging/enjoydslr/index.html.

[matthewwong]

I understand rite now......which means if I wanna take wide angle photos, I should consider to get 5D....
By the way, How do I know which one is FF like different brand...such as Nikon, Sony and so on

[philleung]

It is not necessarily true that only FF camera like 5D or 1Ds can take wide angle shot. In fact, it depends on the combination of lens and camera you use. Despite the image quality in this discussion, a 1.6x camera with 10-16 EFS lens will give you an equivlent 16mm wide shot while a FF camera with 16-35 EF lens will also give a 16mm wide shot. However, you only need to pay around $10K for the 1.6x camera combination while the FF set will easily set you back at $30K+.

You can look at the specification of different camera and they will stated the crop factor like 1x, 1.3x, 1.5x, 2x, etc. Please noted that only 1x is considered as FF while others are crop cam.

[pongyee]

I understand rite now......which means if I wanna take wide angle photos, I should consider to get 5D....

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there are also wide angle lenses for APS-C sensor cameras, e.g. the TOKINA 116.