What is 14mm equivalent?

S

sirk

Active member
Hello,
I hope I will receive a 28mm f/2.8 canon fd which I got cheap on ebay. I also got one of those adapters for only 40 euros (incl shipping from china) you can get them REALLY cheap if you look out (international search).

so there is this crop factor thing which is confusing me. I want to use the 28mm lens, and it's supposed to be a wide lens actually, but I wont get a very wide angle with it, will I? (because of that crop factor?)

my question actually is: what would be the equiv. focal length of a 'dump' lens, like a canon FD with adapter to get the same angle as the kit lens can capture with 14mm?

any ideas?
 
I thought the kit lens is "real" mm as well. That is to say if you put the kit lens at 28mm it will give you the same picture as the Canon 28mm. So to get the same view as the 14mm kit lens you'd need a 14mm lens. But the actual resulting picture for either lens is really 2x. To get a real 14mm field of view you'd need a 7mm lens.
 
Oh no here we go again.

The kit lens does not state any FOV crop conversion!

In fact no serious camera I know of in the still photography world lists FOV equivalents; 14mm is 14mm is 14mm. The equivalents are only mentioned in point and shoots and bridge cameras. 4/3s, Canon APS-C,H, full-frame, Nikon FX and DX, Pentax DA and FA, etc all state the actual focal length of the lens, that is, without any FOV crop equivalents!

If you want an FD mount lens to perform the same as the kit lens at 14mm, you need a 14mm lens. Plain and simple*.

* Actually not so simple, since many lens manufacturer's "cheat" when stating focal lengths. But that's not within the scope of a theoretical discussion!
 
I'm going to add that people should be very careful when stating equivalent FOVs; earlier on I got confused with Kholi describing 35mm equivalent because I did not think of the S35 format and was thinking of still photography 35mm FOV instead.

Moral of the story people visualise and mentally calculate focal lengths with different mindsets. There is no "right" or "wrong" equivalent; only when it is ambiguous then do the problems start occuring!
 
I don't have a full frame DSLR to compare but I did a test with a canon FD 50mm on the GH1 taking a still pic and the kit lens on 50mm taking a still pic and as far as I recall the FOV on each still was the same.

Going by the x2 crop factor rule. If you want the equivalent of a 14mm lens on a full frame, then it would be equivalent to a 7mm fish eye on the GH1.
I understand what you're saying yslee. You're saying that a 14mm lens and the kit on 14mm is the same.

EDIT: oops I re-read the original post. my bad, yes yslee is right. if you want it to match the kit on a gh1 then yes just use a 14mm, I thought you meant full frame
 
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