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12-23-2013, 03:35 AM   #16
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Lets hope it has decent video :-)

12-23-2013, 11:00 AM   #17
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This topic has always been the biggest problem in my modern relationship with Pentax. Coming from the film era I wanted to keep the nice A series lens collection that I am comfortable using as I kept my film cameras and added a digital camera to the lineup. I only use A lenses as they are the only ones that work perfectly with both worlds (don't get me started on the damn green button or manual focusing an AF lens).
I immediately realized that my A50 was now a totally different lens with such a narrow field of view as to be useless for its original purpose, and will eventually have to switch to the A35 (when I have money and an F2 version comes up at the same time). My most used lens now is the A24-50 and even that used to be a much more versatile lens, now I really don't have a proper landscape lens at all. I used to be able to use my 70-210 as a city walk around because 70 was just wide enough and the 210 allowed sniping at a distance.
That is something that I like to remind people, Pentax has wonderful backwards compatibility, but the FOV is shifted so badly with a crop sensor that you are operating with the widest of the full frame film era lenses most of the time which happen to be the rarest and most expensive. Frustrating when there is a butt load of fast high quality primes for dirt cheap in the middle focal lengths out there. Where it hurts the most is giving up field of view to get any magnification in a telephoto, and putting up with way more distortion issues (or expensive corrections) to go wide enough for a proper landscape lens.

Bottom line is while it was helpful (or not) to help people understand back when APSC first became standard, they should just drop the comparison to FF and just think about crop focal lengths as their own world, you don't see people thinking of a FF lens as a crop percentage of a medium format (yes I know its a different mount), medium format users just think of each focal length differently when using those cameras and lenses.
12-23-2013, 08:15 PM   #18
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QuoteOriginally posted by Ploki Quote
Hi, I gathered as much and I hope its correct:
- the APS-C cameras have a crop factor around 1.5x.
- that means the effective focal length for old lenses is whatever is written on the lens x 1.5.
No, the focal length stays the same. Only the field-of-view captured on the sensor and seen through the viewfinder changes to mimic that of a 1.5 greater focal length FF lens.

I'm still a tad confused though; technically 50mm prime is a 75mm prime. Again, no. 50mm is 50mm. So if I want to shoot with a 50mm like the old film SLRs worked, I'd actually need to get a 35mm lens? Only if you want the FoV to be the same. But as far as my experience go larger field of view has more distortion, Why do you say that? meaning 35mm x crop factor won't look the same as 50mm despite the fact that image should technically look the same size. Am I getting this right?

That would mean APS-c actually brings nothing good to the table at all, at least I can't see it. Except greatly reduced cost when it comes to buying a camera. Seems like it does the same as a teleconverter would do (optically magnifies and crops). Again, no, because the crop factor is not magnification like that of a teleconverter. Except for telezooms, where you don't loose light and resolution to get greater detail.

Why didn't they bring the lens closer to the sensor so it wouldn't crop? Because that would have made the lenses impossible to focus correctly because, they would not have the same registry distance.

Are the lenses made for APS-C (that show a circle crop on a full frame) designated with crop factor being taken into account, meaning that 50mm for APS-c would technically not be the same as a normal 50mm? Lenses made for APS-C cameras have no crop factor, and their stated focal lengths are as they are. Sometimes you will see a stated equivalent 35mm range, but that is erroneous. The stated focal length on the lens already is the 35mm equivalent.

Read my response notes above.

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