Confused about crop sensor vs focal length

[mchap7777]

480sparky...(or anyone who knows what they are talking about) maybe you can help me with this also. I "get" the above...but I'm still stuck on this issue - that goes a bit deeper. [Sorry - I'm dense and maybe think too much]. My question centers on whether there is a difference between a DX lens and an FX lens (does the DX lens compensate?). I say this because I have several Nikon lenses with "DX" on them. If I put a "DX" lens (I have a Nikon crop frame camera) on my DX camera - let's say a 50mm lens, then I am seeing ("angle of view" - or "field of view") the same as a 50mm full frame lens on a full frame camera? I say this because all the things I'm reading seems to say if I put the exact same lens on the two different camera bodies - then there is the crop difference - I understand this. But I guess I wondering if the "DX" lens made for a DX camera somehow equalizes the field or angle of view - and the "problems" come in when you mismatch? This presents several scenarios in my mind - running between DX and FX lenses AND DX and FX camera bodies (sensor sizes):
DX Cam with DX lens
FX Cam with FX lens
DX Cam with FX lens
FX Cam with DX lens

Please run through these four possibilities for me, and clear up my confusion. (Maybe I'm assuming possibilities that are not even real).

Main question though is: Is 50mm DX lens on DX camera a true 50mm field of view? (Compared to 50mm Full frame lens on FX camera)?

Thanks in advance.

 

[480sparky41 40]

480sparky...(or anyone who knows what they are talking about) maybe you can help me with this also. I "get" the above...but I'm still stuck on this issue - that goes a bit deeper. [Sorry - I'm dense and maybe think too much]. My question centers on whether there is a difference between a DX lens and an FX lens (does the DX lens compensate?). I say this because I have several Nikon lenses with "DX" on them. If I put a "DX" lens (I have a Nikon crop frame camera) on my DX camera - let's say a 50mm lens, then I am seeing ("angle of view" - or "field of view") the same as a 50mm full frame lens on a full frame camera? I say this because all the things I'm reading seems to say if I put the exact same lens on the two different camera bodies - then there is the crop difference - I understand this. But I guess I wondering if the "DX" lens made for a DX camera somehow equalizes the field or angle of view - and the "problems" come in when you mismatch? This presents several scenarios in my mind - running between DX and FX lenses AND DX and FX camera bodies (sensor sizes):
DX Cam with DX lens
FX Cam with FX lens
DX Cam with FX lens
FX Cam with DX lens

Please run through these four possibilities for me, and clear up my confusion. (Maybe I'm assuming possibilities that are not even real).

Main question though is: Is 50mm DX lens on DX camera a true 50mm field of view? (Compared to 50mm Full frame lens on FX camera)?

Thanks in advance.

The biggest difference between a DX and an FX lens of the same focal length is the diameter of the image projected. DX lenses only need to make a circle big enough to cover the smaller DX sensor. FX lenses need to make a bigger circle to cover the larger sensor.

A DX lens and an FX lens will be the same on a DX body. A 35mm DX lens will look the same as a 35mm FX lens through a DX viewfinder.

On an FX body, you will have three choices..... let the camera automatically detect a DX-format lens and record just the DX-format image, or shoot in either DX or FX mode regardless of what lens is attached.

 

[mchap7777]

Thanks!

 

[glun]

If you have a EF-S 17-55mm lens on a canon crop sensor does the 1.6 factor still apply? Is it 17mm or 27mm?

Flare

Yes the 1.6 factor still apply. The focal length of your lens is still 17mm but because of the crop senor of your camera it becomes 27mm.

 

[table1349]

If you have a EF-S 17-55mm lens on a canon crop sensor does the 1.6 factor still apply? Is it 17mm or 27mm?

Flare

Yes the 1.6 factor still apply. The focal length of your lens is still 17mm but because of the crop senor of your camera it becomes 27mm.

NO it does not become 27mm. Focal length is focal length. It is a property of physics. Your 17mm focal length gives you the area of view of a 27mm lens.