tradergeorge Loc: Newport, Kentucky

[quote=CraigFair]

What I am saying is that you are cropping the frame that would normally fit into the FX sensor to the size that fits into the DX sensor (smaller)..So, when you blow this back up to whatever size, it gives the appearance of having been changed, when in fact you are looking at the same image, just a smaller part of it. That is why I say that the optical characteristics of the lens has not changed in any way. You get the "angle of view" of a larger lens, but not anything else to goes with having a larger lens...That is why I say it is a lie and a boondoggle...

In fact, when you install a DX lens on your full frame camera, it will default to a "DX Mode", where it simulates the smaller sensor. This is to avoid all the bad things that happen when you focus the FX lens on a sensor that is larger than it is designed for. Just keep in mind that there is no free lunch. Putting a 200mm lens on as DX camera does not automatically and magically make it a 300mm lens, or anything close to "equivalent" in anything else besides that simulated "angle of view"...

lighthouse Loc: No Fixed Abode

Yep, like I said - semantics, schemantics.

tradergeorge Loc: Newport, Kentucky

Wording becomes important when people are convinced that they are getting something they are not, and even their trusted mentors say little to convince them otherwise. It is like calling the Korean War a "police action"...You might as well say that a 200mm lens with two 2X converters stacked behind it is "equivalent" to an 800mm lens. We toss around terms like "equivalent", when only one attribute is considered. This misleads people and is where the lie is.

What I fail to understand is why, when we are so careful in these forums when considering things like extra glass surfaces, ISO vs noise, and other things, that we gloss over a major point like this.

lighthouse Loc: No Fixed Abode

George, if you had an image taken with a little point and shoot at 4mm focal length, and someone asked you the focal length of the shot - what would you tell them?
Because unless you would just say "4mm." and not embellish or qualify your answer in any way at all - then your whole argument that you insist on having here is a crock of sh!t.

My first half decent digital camera was a Panasonic Lumix FZ20 (I think).
On the barrel it had written the focal range - and straight after that it had something like 28-432mm 35mm equiv

There was article discussing the furore of the British princess being photographed topless not so long ago. That article specifically did describe the lenses and extenders used and the focal length equivalence.

This is terminology that is in common use all the time.
And before I joined UHH I never saw anyone anywhere have the pedantic attitude to it that some here seem to have.

This equivalence helps people to purchase the lens that they need to cover a specific range or length. Its not hard. its not rocket science, its simplification.

CraigFair Loc: Santa Maria, CA.

Well said Lighthouse, ""equivalence or equiv"" is used everywhere in Photography.
Craig

waykee7 Loc: Cortez, Colorado

It's interesting that when I shot a Pentax 6x7 and I had a 105 mm, it rendered images very similar, in terms of perspective not quality, to a 50 mm on a 35mm camera. Did that make a difference to me? You bet! My 200 mm was about equivalent to a 100mm, and my 50mm was a wide angle. My 135 macro was roughly equivalent to a 60mm lens on a 35mm camera. So, other than a semantic argument, I don't understand how that's different from a 300mm lens on my 1.6crop sensor looking a lot like an image shot at 480mm on a 35mm camera?

CraigFair Loc: Santa Maria, CA.

"I shot a Pentax 6x7 and I had a 105 mm" Is this the Camera and Lens you used. Because I think the Lens in the picture is Specific to that Camera Body?
Craig

Pentax 6x7 & 6x7 f/2.4 105 mm Lens

(Download)

tradergeorge Loc: Newport, Kentucky

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