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03-30-2013, 09:12 AM   #16
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QuoteOriginally posted by wes k Quote
That's great guys, but I already understand crop factor, and wasn't actually what I asked, but i've got an answer so, thank you.
I should probably have asked - "do Pentax compensate for the crop factor when labelling their DA lenses?" (this might sound strange to you all, but makes sense to me)
Well, the reason it doesn't make sense to compensate for the crop factor is because things would become a mess, and because they would be lying. A 35mm lens is and will always be a 35mm lens, calling it a 53mm would be a lie.
Imagine, Canon labeling with their 1.6x and 1.3x crop sensor, Pentax with their 1.56x and 5.6x crop...
For that reason, every company labels their lenses by the fullframe focal length.


Last edited by GabrielFFontes; 03-30-2013 at 09:57 AM.
03-30-2013, 09:15 AM   #17
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QuoteOriginally posted by wes k Quote
I should probably have asked - "do Pentax compensate for the crop factor when labelling their DA lenses?" (this might sound strange to you all, but makes sense to me)
Only P&S cameras are labeled that way.
03-30-2013, 09:39 AM   #18
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QuoteOriginally posted by GabrielFFontes Quote
For that reason, every company labels their lenses by the fullframe focal length.
I don't mean to pick on you here and I understand what your meaning is, but statements like this tend to add to people's confusion. There is no such thing as "fullframe focal length" focal length is focal length and has absolutely nothing to do with the dimensions of the media that the lens will be projecting the image onto.
03-30-2013, 09:58 AM   #19
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QuoteOriginally posted by Parallax Quote
I don't mean to pick on you here and I understand what your meaning is, but statements like this tend to add to people's confusion. There is no such thing as "fullframe focal length" focal length is focal length and has absolutely nothing to do with the dimensions of the media that the lens will be projecting the image onto.
Yes, yes, sorry, you're right...i actually contradicted myself in there, since i said "a 35mm lens is and will always be a 35mm", but then said "fullframe focal length"...i don't even know why i said that haha

03-30-2013, 05:36 PM   #20
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QuoteOriginally posted by wes k Quote
I should probably have asked - "do Pentax compensate for the crop factor when labelling their DA lenses?"
No, if you're smart enough to use a Pentax,
you're smart enough to multiply by 1.5 in your head.
03-30-2013, 05:42 PM   #21
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QuoteOriginally posted by lytrytyr Quote
No, if you're smart enough to use a Pentax,
you're smart enough to multiply by 1.5 in your head.
Not if you count with your fingers. Hmmmm how do I count .5 with my fingers?
03-30-2013, 05:56 PM   #22
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QuoteOriginally posted by Driline Quote
Hmmmm how do I count .5 with my fingers?
I believe the yakuza can help you with that.
03-30-2013, 09:19 PM   #23
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QuoteOriginally posted by lytrytyr Quote
I believe the yakuza can help you with that.
LOL , in my town it would be the Mafioso.

03-31-2013, 06:59 AM   #24
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QuoteOriginally posted by Na Horuk Quote
The only reason people even talk about "FF equivalent" is because this helps out old photographers who used film for decades and already know how a 50mm and 35mm looks like on film and would be surprised if they used it on a crop.
That may be the reason "equivalent" focal lengths originated, I don't really know. But the value of it now is that it enables us to compare across systems. Comparing FOV of a 50mm lens on a Q, Nikon 1, M4/3 and APS-C is dead simple because you can easily convert all to FF equivalents.

QuoteOriginally posted by kerrowdown Quote
Absolutely spot on, it's an old chestnut this one, but it's been well explained again in this thread.
I just wish someone could explain crop factor to 4/3 and M4/3 shooters and have it stick. I could scream every time I hear it "My 300mm is a 600mm lens on my Panalympus body. Have you ever seen how big a FF 600mm lens is?"
03-31-2013, 08:08 AM   #25
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QuoteOriginally posted by Parallax Quote
statements like this tend to add to people's confusion. There is no such thing as "fullframe focal length"
With all the different sizes out there now,
from 1/2.3 sensors to 10 x 8 in. sheet film,
we do need some way to compare lenses.

Angles don't work too well
(diagonal, horizontal, . . . ?),
so "FF equivalent" is probably the best way to go.
"FF" has the advantage of being somewhere in the middle,
and having a defined 3:2 aspect ratio.

So we can appreciate that the 01 prime on a Q
is like the FA 31 on APS-C,
in particular since both are "47mm FF equivalent."
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