FX vs DX lenses on APS-C bodies: I have read UHH for some time, but am participating now for the first time. I have a Nikon D5200 and recently purchased a Sigma Zoom 50-500mm f4.5-6.3...

TrickyDick

I have read UHH for some time, but am participating now for the first time.

I have a Nikon D5200 and recently purchased a Sigma Zoom 50-500mm f4.5-6.3 FX lense. Several reasons:

1. General quality of FX over DX lenses;
2. I can upgrade to FF later and still use the lense if I want.
3. My belief that given the same lense, the FX will give me 750mm from the center of the lense and project it onto the full D5200 sensor still using all 24mp. That same lense on a FF body with 24mp sensor would have to be cropped to the 750mm view and loose some of the pixels and therefore quality because it is using just part of the FF sensor results. Thus, I assume, generally speaking, is that this FX lense on an APS-C body would probably result in a slightly sharper photo for the 750mm distance or view.

Am I right about #3 above?

I am also curious as to your thoughts on this body and lense combination.

Dngallagher Loc: Wilmington De.

TrickyDick wrote:

I have read UHH for some time, but am participatin... (show quote)

Yes, a DX sensor has a 1.5 crop factor so 500 mm lens = 500x1.5=750 mm in 35 mm speak ;)

It will actually spill over the DX sensor, as the FX lens projects a larger image...but the DX sensor will be getting an image from the "sweet spot" of the FX lens...

I have several FX lenses that I use on a DX body, work fine....

This from the Nikon site sums it up....

http://www.nikonusa.com/en/Learn-And-Explore/Article/g588ouey/the-dx-and-fx-formats.html

lighthouse Loc: No Fixed Abode

TrickyDick wrote:

I have read UHH for some time, but am participatin... (show quote)

OK, prepare for posters tied up in semantics telling you why you are totally wrong ... and then totally ignore them.

You have described it in an awkward roundabout way but basically yes, you will get a 750mm equivalent image from the centre of the lens. Your camera will crop that image area out of the lens and use your full 24megapixels to record it.

lighthouse Loc: No Fixed Abode

Dngallagher wrote:

Yes, a DX sensor has a 1.5 crop factor so 500 mm lens = 500x1.5=750 mm in 35 mm speak ;)

It will actually spill over the DX sensor, as the FX lens projects a larger image...but the DX sensor will be getting an image from the "sweet spot" of the FX lens...

I have several FX lenses that I use on a DX body, work fine....

This from the Nikon site sums it up....

http://www.nikonusa.com/en/Learn-And-Explore/Article/g588ouey/the-dx-and-fx-formats.html

Sorry, your words are correct, but that diagram is misleading.
That centre image is not a 1.5X crop of the FX image.
There is virtually no difference in those two images.
The cropping/enlarging effect is much more pronounced than that.

SonnyE Loc: Communist California, USA

FX Lens on DX camera = good.
DX Lens on FX camera = not so good.

Any questions?

As for me, I don't expect to wear out my DX camera. So I don't care.

amehta Loc: Boston

TrickyDick wrote:

I have read UHH for some time, but am participatin... (show quote)

You are mostly right about the effect of the DX sensor as opposed to a FX (full frame) camera. The basic benefit is that the 24mp DX sensor has a higher pixel density than the 24mp FX sensor.

For the part which is not states quite right, let's consider the DX 55-300mm and FX 70-300mm lenses. With the D5200, both will give a 450mm equivalent field of view. It does not matter if it is a DX or FX lens.

SteveR Loc: Michigan

Dngallagher wrote:

Yes, a DX sensor has a 1.5 crop factor so 500 mm lens = 500x1.5=750 mm in 35 mm speak ;)

It will actually spill over the DX sensor, as the FX lens projects a larger image...but the DX sensor will be getting an image from the "sweet spot" of the FX lens...

I have several FX lenses that I use on a DX body, work fine....

This from the Nikon site sums it up....

http://www.nikonusa.com/en/Learn-And-Explore/Article/g588ouey/the-dx-and-fx-formats.html

gallagher....The problem with the image that you posted is that the dx image appears smaller than the fx image. In fact, the image of the mountain projected onto the sensors by the lens of the same focal length would be the same size on both sensors.

http://www.google.com/search?q=crop+vs+full+frame&client=firefox-a&hs=S1q&rls=org.mozilla:en-US:official&tbm=isch&tbo=u&source=univ&sa=X&ei=Xbq4UYnRJImEyAH43IHwBg&ved=0CDgQsAQ&biw=1978&bih=866#facrc=_&imgdii=_&imgrc=r9SOPeD1yoAKnM%253A%3BohOxB0R6MlhkNM%3Bhttp%253A%252F%252Flowenddslr.com%252Fimg%252Fcrop-circle.jpg%3Bhttp%253A%252F%252Flowenddslr.com%252Ftutorials%252Fcrop-factor.php%3B450%3B450

SharpShooter Loc: NorCal

TrickyDick wrote:

I have read UHH for some time, but am participatin... (show quote)

Tricky, welcome to the Hog.
1, I don't think there is anything inherantly better about ff lenses vs crop. A better indicator would be strictly cost. A more expensive crop lens is likely better than a less expensive FF lens.
That said most crop lenses don't get very long or fast, so any advantages of a crop lens is lost on big and fast lenses.

2, of course you can always upgrade, but the truth is, most shooters will never go FF.
I personnally would not go out of my way to load up on FF lenses, because in 3 years I might go to FF. But that's just me! Also, most of the advantages of crop lenses are lost by using FF lenses on a crop camera.

3, I'll have to read this later, as you completely lost me.
I will say that the lens, whether FF or crop has absolutely NOTHING to do with the cameras megapixels!
Again welcome. ;-)
SS
PS, by THIS body, are you referring to the cameras body, or your own body? :lol:

SonnyE Loc: Communist California, USA

Afterfart: Compared to my struggles since the early mid-1990's with the primitive digital offerings of the day, I'm in Heaven with my DX. And 24.5 mega pixels is outstanding!
Count me firmly entrenched in the DX stable. ;-)

SteveR Loc: Michigan

One of the advantages of an FX lens on a DX body, is that the center, sweet, portion of the lens projects onto the sensor. It's one reason I like the Nikon 28-300mm on my D7000.

DavidPine Loc: Fredericksburg, TX

An FX will work very well on a ASP-C. The crop factor of 1.5 is not a zoom but is an estimated field of view.

Dngallagher Loc: Wilmington De.

lighthouse wrote:

Sorry, your words are correct, but that diagram is misleading.
That centre image is not a 1.5X crop of the FX image.
There is virtually no difference in those two images.
The cropping/enlarging effect is much more pronounced than that.

SteveR wrote:

gallagher....The problem with the image that you p... (show quote)

Lighthouse - SteveR :the diagram denotes the SENSOR size, not the image size from the lens... meaning, as stated, the image from an FX lens on a DX camera will spill over the sensor, the DX sensor will collect light from the CENTER of the image.

The link went to the Nikon site which goes into more detail....(complete page is below)....

(Download)

SteveR Loc: Michigan

Dngallagher wrote:

Lighthouse - SteveR :the diagram denotes the SENSOR size, not the image size from the lens... meaning, as stated, the image from an FX lens on a DX camera will spill over the sensor, the DX sensor will collect light from the CENTER of the image.

The link went to the Nikon site which goes into more detail....(complete page is below)....

Dn....You're right....but it also spills over an FX sensor. See my link. The circle is the image projected by the lens. It is round. The large rectangle is the FX sensor. There is a portion of the image from the round lens that "spills over" that sensor as well.

Dngallagher Loc: Wilmington De.

SteveR wrote:

Dn....You're right....but it also spills over an FX sensor. See my link. The circle is the image projected by the lens. It is round. The large rectangle is the FX sensor. There is a portion of the image from the round lens that "spills over" that sensor as well.

Agreed - but figured that was more info then was needed for the OP ;)

SteveR Loc: Michigan

Dngallagher wrote:

Agreed - but figured that was more info then was needed for the OP ;)

That, though, could be confusing. The circle that I posted is what helped me to understand the whole crop, full frame thing. It's what made the light bulb go on.