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08-05-2010, 12:08 PM   #31
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QuoteOriginally posted by CWyatt Quote
Not necessarily, full-frame might give you the resolution to crop more tightly, which is essentially what the APS-C is doing with your full-frame lens anyway.
I'm afraid I'm missing something.

FF is about twice the area of an APS-C sensor, right?

Given use of the same lens, the image of the C-5 on that FF sensor will be exactly the same size as it is on the APS-C sensor, only with a lot more blue sky around it. The FOV on FF is based on the lens' true 300mm focal length and the FOV on the APS-C looks like a 450mm-equivalent lens was used.

In PP, I can crop away the extra blue sky on the FF image and break even - now the aircraft image is the same portion of the total image. To keep just the same number of pixels representing the aircraft, the FF sensor must have slightly more than double the number of pixels as my APS-C sensor. That's 14.6 MP X ~2 = 30+ MP.

If I need 30+ MP to break even, then to get an improvement I'll be waiting a while and then spending a very large amount of money for what is, today, an MF sensor.

Again, am I missing something?

08-05-2010, 12:29 PM   #32
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QuoteOriginally posted by glanglois Quote
I'm afraid I'm missing something.

FF is about twice the area of an APS-C sensor, right?

Given use of the same lens, the image of the C-5 on that FF sensor will be exactly the same size as it is on the APS-C sensor, only with a lot more blue sky around it. The FOV on FF is based on the lens' true 300mm focal length and the FOV on the APS-C looks like a 450mm-equivalent lens was used.

In PP, I can crop away the extra blue sky on the FF image and break even - now the aircraft image is the same portion of the total image. To keep just the same number of pixels representing the aircraft, the FF sensor must have slightly more than double the number of pixels as my APS-C sensor. That's 14.6 MP X ~2 = 30+ MP.

If I need 30+ MP to break even, then to get an improvement I'll be waiting a while and then spending a very large amount of money for what is, today, an MF sensor.

Again, am I missing something?
No, you're correct. Cropping an FF image won't yield the same quality (or at least, resolution) as shooting the same object with an APS. Different tools for different purposes.
08-05-2010, 01:27 PM   #33
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Thanks, Andi. I got it right - once in a row ...
08-07-2010, 04:46 PM   #34
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Depends on your APS-C camera. As you point out, to re-create what you can get by cropping a K-7 image might be require a very high resolution FF. But to out-resolve a K10D, esp at higher ISOs, I think would be very manageable by cropping a higher-end FF.

08-07-2010, 06:22 PM   #35
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QuoteOriginally posted by Lowell Goudge Quote
just go out and get a PZ-1. they're cheap and you can always check your exposure with a digital, then make the shot on film with the PZ-1

When I went digital, my *istD came with an 18-35mm full frame lens (from the *ist film days)

It was not wide enough on digital so I went the two bdoy approach, digital for normal to tele and film for wide angle.
Pentax PZ-1 75th Anniversary Special Edition on eBay.ca (item 250677811283 end time 11-Aug-10 21:22:57 EDT)
08-07-2010, 06:26 PM   #36
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QuoteOriginally posted by CWyatt Quote
Depends on your APS-C camera. As you point out, to re-create what you can get by cropping a K-7 image might be require a very high resolution FF. But to out-resolve a K10D, esp at higher ISOs, I think would be very manageable by cropping a higher-end FF.
A proper FF to take full advantage of lens resolving powers should be over 20MP. Less is a waste, but as tech stands now, the main advantage is higher ISO capabilities. The future holds 30MP FF with very high ISO quality (D700 or better).

At that point, you can crop and beat the APS-C handily on resolution. You'll get that 2x pixel count AND the wide angle.
08-10-2010, 08:01 PM   #37
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QuoteOriginally posted by paperbag846 Quote
Now for a photographic question - in this scene I focused on the horizon because I wanted to get those two buildings as sharp as possible.

Would there be a way to get both the foreground and the buildings in focus?
There's no magic. Stop down as far as you can stand (diffraction isn't the end of the world), experiment with where to focus to get best the balance of focus between foreground and background according to your tastes. Focus is not a yes/no thing only - it's a matter of degree.

And of course, a FF camera would have less DOF for the same FOV and aperture.

08-10-2010, 11:01 PM   #38
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Hasselblad got it right a half century ago: produce a specialized camera for wide angle work. The non-retrofocus 38mm Biogon in the SWC is miles better than the retrofocus 40mm Distagon for the reflex body. Much as I don't personally care for electronic viewfinders, I think Pentax could produce one with a true (non-retrofocus) wide angle and a Kodak chip with offset microlenses such as used in the Leica M9.
08-11-2010, 12:01 AM   #39
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As an aside, Pentax apparently has yet to answer this question for their 645D system as well. Both Leica and Mamiya have superwide lenses (circa 28mm). The 35mm Pentax becomes more like a 45mm (28mm equiv. on FF 35mm body) because of the crop sensor. They're going to need something wider to compete.
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