Why does my 17-55mm 2.8 take a different picture than a 16-35mm 2.8?

[Alex_B]

No it means for a DX sensor a 17 is a 17 and not some differend adjusted for "crop factor" focal length. Otherwise why bother making DX formatted lenses.

a 17mm is always a 17mm, no matter on what sort of sensor or film you use it on. but the angle of view is small on a crop sensor.

DX lenses can just be smaller and lighter, and cheaper to produce, since they can survive with a smaller image circle.

A 17mm DX lens on a DX sensor gives around 79 degrees angle of view. on a full frame sensor, you would get the same angle of view of 79 degrees, if the focal length was 1.5x17mm. This is the meaning of the so called crop factor.

 

[Socrates]

a 17mm is always a 17mm, no matter on what sort of sensor or film you use it on. but the angle of view is small on a crop sensor.

DX lenses can just be smaller and lighter, and cheaper to produce, since they can survive with a smaller image circle.

A 17mm DX lens on a DX sensor gives around 79 degrees angle of view. on a full frame sensor, you would get the same angle of view of 79 degrees, if the focal length was 1.5x17mm. This is the meaning of the so called crop factor.

Your explanation is correct. More detail is here:
http://support.nikontech.com/cgi-bi...F9zZWFyY2hfdGV4dD1EWCBGWA**&p_li=&p_topview=1

 

[sabbath999]

oh, and it is Canon by the way, Cannons are meant to shoot people in a slightly different way.

Whenever I see this, I am always tempted to ask a poster if he has a howitzer, a smoothbore Napoleon, a Parrot or a Dahlgren.

Personally, I prefer Napoleon's... they have a better "bark".

 

[JIP]

Hey Soc that link you posted is fine and I saw it in my lookng around for an answer but in all the illustrations they showed there were no DX lenses so I do not think it really fits in this discussion or I woul dhave posted it myself.

 

[sabbath999]

No it means for a DX sensor a 17 is a 17 and not some differend adjusted for "crop factor" focal length. Otherwise why bother making DX formatted lenses.

A 17 is a 17, yes, but DX has absolutely nothing to do with "perceived" focal lengths.

A DX 17 on a 1.5 crop lens is EXACTLY the same focal length as a non-DX one, offering EXACTLY the same field of view... which, by the way, is 25.5mm.

 

[Alex_B]

Hey Soc that link you posted is fine and I saw it in my lookng around for an answer but in all the illustrations they showed there were no DX lenses so I do not think it really fits in this discussion or I woul dhave posted it myself.

Yes, but what the links says, and what i said, is that the DX on the lens has no meaning regarding your resulting angle of view. it is the sensor size and the focal length which do define it.

 

[Alex_B]

Personally, I prefer Napoleon's... they have a better "bark".

filters for that diameter must be very costly ...

 

[sabbath999]

filters for that diameter must be very costly ...

Ya, and the filters break a lot too...

 

[Alex_B]

Ya, and the filters break a lot too...

:lmao:

 

[GTHill]

A lot of the 16-35mm shots you're referring to are from his Canon 5D, which is a full-frame camera. Your D300 has a crop factor of 1.5, so you have to multiply the focal length you're shooting at by that to get the "equivalent 35mm / full-frame" point of view. 17mm on a Nikon/DX is equivalent to 26mm in 35mm/FF terms, and thus a lot less wide than 16mm on a full-frame (1.0x crop factor) Canon 5D. To get super wide like that on a Nikon DX you need something like a 12-24mm (Nikon, Tokina) or a Sigma 10-20mm. The widest you can get is the 10.5mm DX fisheye which gives a 180-degree diagonal field of view, and 160-degrees horizontally, but fisheye lenses aren't always the best for landscape photos.

Here's one from my 10.5 and D80.

I really like that picture! That is what I'm looking for. I'm going to look at the 12-24mm today and see what happens. Thanks!

Gene

 

[Dubious Drewski]

I get a little bit confused when I'm trying to pick out a lens. I recently saw some sample shots that someone had taken with a 28mm lens and I thought "hmm, that's nice and wide, I need one of those", so I like an idiot, I paid for one on ebay right away. Now I've had this realization that I have the Kit 18-55 lens already. But the thing is, those 28mm samples looked wider than what I get with my kit lens!

Bah, owell, the 28mm came with a camera, so now I'll have a K1000 to play around with.

 

[Mike_E]

I get a little bit confused when I'm trying to pick out a lens. I recently saw some sample shots that someone had taken with a 28mm lens and I thought "hmm, that's nice and wide, I need one of those", so I like an idiot, I paid for one on ebay right away. Now I've had this realization that I have the Kit 18-55 lens already. But the thing is, those 28mm samples looked wider than what I get with my kit lens!

Bah, owell, the 28mm came with a camera, so now I'll have a K1000 to play around with.

Try looking up hyperfocal length and setting your 28mm prime to that. You might just be happy you bought it!

Also if anyone is interested, a DX lens is designed to be smaller than an FX lens and won't cover all the frame of the FX. Although Xmm is Xmm regardless, the term 'crop factor' comes into play because with the DX sensor you are effectively taking a piece (cropping) of what would have been your print and blowing it up to fill out the dimensions of the print.

 

[Socrates]

Yes, but what the links says, and what i said, is that the DX on the lens has no meaning regarding your resulting angle of view. it is the sensor size and the focal length which do define it.

Again absolutely correct. In fact the same thing is true if you put a DX lens on an FX body. The only issue is that the DX lens will not provide lighting to the entire area of the FX sensor and, as a result, the outer edges will be dark.

 

[Socrates]

Try looking up hyperfocal length and setting your 28mm prime to that. You might just be happy you bought it!

Also if anyone is interested, a DX lens is designed to be smaller than an FX lens and won't cover all the frame of the FX. Although Xmm is Xmm regardless, the term 'crop factor' comes into play because with the DX sensor you are effectively taking a piece (cropping) of what would have been your print and blowing it up to fill out the dimensions of the print.

I'm familiar with "hyperfocal distance" for focusing but what is "hyperfocal length" and how does it relate to Drewski's issue?

 

[Socrates]

No it means for a DX sensor a 17 is a 17 and not some differend adjusted for "crop factor" focal length. Otherwise why bother making DX formatted lenses.

An FX lens casts light on an area much greater than the physical size of a DX sensor and therefore you're paying for more lens that you need. Purchasing an FX lens for a DX body is roughly comparable to putting premium gasoline in an automobile designed for regular octane. A DX lens is a cost-effective alternative that illuminates only the area of a DX sensor.

Of course, some times you have no choice. The lens that you want might not be available in a DX configuration. Kinda like a gasoline station that ran out of regular gasoline.