What size is my lens on a200

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debrito

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hi
dont know if i have got this rigt but someone told me that if i got a 50mm lens that it would not be 50mm it would be more like 80mm ???
i'm a bit confussed

gear sony a200 m42 adaptor 50mm pentacon 1.8


help help ??
whats it all about
 
It's due to the 'crop factor'. I think it'll be a 1.6 crop factor (the sensor is 1.6 times smaller than 'full frame' - 35mm film). Hence the effective focal length is 50*1.6 = 80mm.

So what you see with a 50mm lens on your camera is the same as if you had a full-frame camera, or a film camera with a 80mm lens mounted on it. The focal length is still 50mm, but you don't see the whole image that the lens produces, only the middle bit. Hope this helps a little!
 
debrito said:
hi
dont know if i have got this rigt but someone told me that if i got a 50mm lens that it would not be 50mm it would be more like 80mm ???
i'm a bit confussed

gear sony a200 m42 adaptor 50mm pentacon 1.8


help help ??
whats it all about
Click to expand...

This is all to do with cropped-sensor sizes. The focal length does not change (50mm is 50mm) however the field of view will be different. For example on a 1.5x sensor a 50mm lens will have a field of view of 75mm.
 
just to claify though - whilst you only see the "middle bit of the image" that is what gets recorded when you click..... you don't lose 1/2 of what you see in the viewfinder......
 
ok thanks for that, i think i understand is that a good think then?
 
it's a 1.5x crop factor on a Sony APS-C.
As for whether it's a good thing it depends what you want/shoot.
If you tend towards telephoto it's probably a good thing but if you want wide it's bad.
 
heidfirst said:
As for whether it's a good thing it depends what you want/shoot.
If you tend towards telephoto it's probably a good thing but if you want wide it's bad.
Click to expand...
Not quite correct, and maybe I'm being a little pedantic here but I feel it's worth correcting...

It's not a 'bad thing' if you want wide on a crop camera as you say, it's just not as good as taking wide on a full frame camera... :)

We don't want people to think that any lenses used to shoot landscapes on anything but a ff camera are 'bad' now do we... (y)
 
theMusicMan said:
Not quite correct, and maybe I'm being a little pedantic here but I feel it's worth correcting...

It's not a 'bad thing' if you want wide on a crop camera as you say, it's just not as good as taking wide on a full frame camera... :)

We don't want people to think that any lenses used to shoot landscapes on anything but a ff camera are 'bad' now do we... (y)
Click to expand...
it's "bad" in that it's harder to go wide on an APS-C on a budget than on FF not that the image will vary between FF & APS-C if shot with equivalent effective focal lengths.
e.g. take a Minolta/Sony 24mm lens (be it prime or zoom) - on FF that's wide but on APS-C it's effectively 36mm in 35mm/FF terms which isn't wide at all...
 
I hear what you're saying heidfirst, and I understand the effect of focal length on ff/crop bodies very well.

However, I think you might be missing my point a little. It's just that any newcomers to photography might interpret what was posted as for landscapes, as all lenses on non ff cameras are bad - when they are certainly not bad. They are just perhaps not as good as images you may capture on ff, but are certainly 'wider' :)
 
what are you too talking about ???

its really not worth it!!!!! you have confussed me know
 
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