Cropped Sensor vs. Full Frame

[lisameowrie]

Does someone mind explaining the difference?

Specifically, I just purchased a used 35mm prime and asked why they were selling and the response was that lens is for a crop body sensor camera and they moved onto full frame. This worries me because that means the lenses I have will not be compatible once I upgrade? I don't want to have to upgrade, I like the lenses I am acquiring!

 

[480sparky41 40]

Your lenses will most likely still work just fine. If the lens is specifically designed for crop sensors, you may need to use a full-frame body in crop mode. If your current lenses are made for full-frame bodies, then you have nothing to worry about.

 

[lisameowrie]

How can I tell what they're made for?

These are my lenses:
Tokina 11-16 f2.8
Nikon 50 f1.8
Nikon 35 f1.8

Not sure if you can tell from that info or not...

 

[Soocom1]

Hold the phone here.

First: If its a Canon, you CANNOT use an EF-s Lens on a Full frame. The focal distance is different. The Lens will stick too far into the camera body and chop the mirror.

If the lenses are EF then you can use those on an APS sensor body.
There are adapters.

If the camera is a Nikon, the focal distances are the same except for one series of SLR's.
If any other manufacturer, then you should really use the lenses for that system.

Back tot he original question:
1: Full frame is the same size as 35mm film. 36 x 24 mm in actual area.
APS-c sensors are the same size as the APS film. Hence the name. 22.5x 15 mm in actual area.

2: The lenses were designed (APS or "crop") to fill the focal area of the APS image area. Full frame lenses have a focal circle that is much larger than the APS to cover the full area of said area. (Think dime vs. quarter.) Full frame lenses work with an APS sensor but it has a "cropped" effect because the image area is smaller.
Now I could go on with this, but Ill let others go further into depth on this.

 

[DavidVote]

I'm assuming you have the 35mm DX version lens for Nikon? Don't worry, it'll still work on a full frame camera but if you use it in fx mode it'll just vignette really badly but it could easily be fixed in post especially if you shoot in RAW.

 

[DarkShadow]

Umm unless I am mistaken doesn't nikon FF Automatically convert to crop mode to avoid vignette if DX glass is used. Either way you have Nikon smart enough to use both FF/DX glass.If its a crop sensor Nikon then it really don't matter does it. Canon Full frame don't convert and can more likely damage the Camera what Soocom said.

 

[Derrel]

As I recall, the 35mm f/1.8 DX-Nikkor covers the 5:4 (aka the 8x10 aspect ratio) crop area that the D3 and D4 cameras offer as an in-camera cropping/capture size option. The 35/1.8 DX is an inexpensive lens, selling for $130-$150 used most often, so, you're not "into it" too much.

This page will explain it a bit better and more thoroughly: Using Nikon DX Lenses on FX Cameras this is for the 35mm f/1.8 DX-Nikkor lens:

"How can you expect it to perform on FX? I was pleasantly surprised. As expected, FX corner performance is nothing to write home about, and some noticeable vignetting is visible. However at larger apertures (larger than F8) the vignetting is bearable. Large aperture prime lenses are often used to draw attention to a single object, and then corner sharpness is seldom crucial. Vignetting may be aesthetically pleasing, and can be corrected to some extent. The center performance remains impressive, as this is what the lens has been designed for."

And again, as I mentioned, I think it "covers" the 5:4 crop area fully, without light falloff. The consumer FX bodies (D600 series for example) do not offer the in-camera 5:4 crop option, but they DO offer the Auto DX crop option, which is smaller, and which the 35/1.8 DX will fill totally. A person can easily turn the Auto DX Crop option to OFF, and that will allow any DX lens to project whatever it "can" onto the entire sensor area of 24x36mm,and you can crop off the dark edges in post.

Some of the newer FX Nikon cameras, like the D750, offer a 1.2x crop, which is a 30x20mm size...

I found these two test shots on Flickr: the first on is shot on a D600, at Full-Frame using the 24x36mm FX frame area. See the upper left corner? That is how bad it vignettes,

fx mode Flickr - Photo Sharing

This second frame is the same scene, but the D600 switched to DX mode:
dx mode Flickr - Photo Sharing

 

[raventepes]

The lenses you have will work on Full Frame bodies, though the Tokina and your new 35mm are designed for crop sensor, so when you switch over, you will be working in crop mode if you put it on, say something like a D610, D750, D810, or D4.

The thing to understand about crop mode is that you don't use the full benefit of the full frame sensor, and kind of as one would expect if they thought about it, it results in a smaller image size because you're quite literally cropping part of the full frame-ness out of it. It boils down to image circles. Full Frame cameras use bigger ones, and crop sensors use smaller ones. Put a full frame lens on a crop sensor body, and you get what's called the "crop factor", which by Nikon's standards will give you a 1.5x magnification of the field of view.

Rather than try to explain it to you, I'll show you. The link below is Nikon's Lens Simulator. Pay close attention to the angle of view indicator and play with various combinations of bodies to lenses. Compare, say full frame lenses on DX bodies, DX lenses on FX bodies, and the same lens on both body types. The camera model itself isn't all that important. Hope it helps some.

Nikon Imaging Products NIKKOR Lens Simulator

 

[astroNikon]

Umm unless I am mistaken doesn't nikon FF Automatically convert to crop mode to avoid vignette if DX glass is used. Either way you have Nikon smart enough to use both FF/DX glass.If its a crop sensor Nikon then it really don't matter does it. Canon Full frame don't convert and can more likely damage the Camera what Soocom said.

Yes and No
The Image Area / Auto DX Crop function can be turned ON/OFF. When turned OFF then it'll vignette as it will expect an image capable of filling the FF sensor.

 

[astroNikon]

Also, DX lenses will have the DX in the name somewhere, such as
Nikon 35mm f/1.8G AF-S DX <-- DX specific lens
compared to
Nikon AF-S 50mm f/1.8 G <-- No DX identifier

FX lenses have no identification for FX/FF.

 

[nerwin]

The only lens you'll really have to replace would be the Tokina 11-16 2.8, but if I'm not mistaken you can use that lens at 16mm on full frame without too much of a vignette. For the time being you can just use it on crop mode. On my D610, I have the DOF preview button set so I can easily swap between fx and dx modes. It can be handy sometimes when you just need that extra reach. Though I hardly use it.

Your 50 1.8G is a full frame lens, so you're good there. If you have the 35 1.8G DX, then it will work decently on full frame up until f/8 before it starts to vignetting severely. When I had my D7000, I LOVED the 35 1.8G it was practically glued to my camera. The main reason why I liked it was because its such a compact lens and the new 35 1.8G fx version is a lot bigger and a lot more expensive which is why when I switched to full frame, I picked up the 35 f/2D because its similar in size of the 35 1.8G DX, more affordable and in my opinion built better.

 

[KmH]

First: If its a Canon, you CANNOT use an EF-s Lens on a Full frame. The focal distance is different. The Lens will stick too far into the camera body and chop the mirror.

The flange focal distance (FFD) is the same for all Canon EF and EF-S DSLRs and lenses - 44.mm.
The common FFD is why Canon EF lenses can be used on Canon EF-S DSLRs.
But EF-S lens bodies do have extra plastic at the back of the lens that protrudes a bit further into the mirror box and will interfere with movement of the main mirror.
But, Canon has designed EF-S lenses so an EF-S lens cannot be mounted on a Canon EF camera body, without modifying the EF-S lens body.
You can indeed use a Canon EF-S lens on a Canon EF camera, if you make a relatively simple change to the EF-S lens by sawing off the plastic piece that interferes with EF camera main mirror movement.
Note that people making that modification do not move the rear lens element and change the focal distance.
EF-S 18-55 3.5-5.6 conversion for EOS 10D

 

[KmH]

How can I tell what they're made for?

Nikon USA's web site has a column on it's DSLR lenses page that shows if a lens is a DX or an FX lens (Lens Format).

Nikon DX lenses use the DX notation in the lens name and on the lens itself.
For example - Nikon AF-S DX Nikkor 18-55 mm f/3.5-5.6G VR II
If the lens name includes no DX or FX identifier - it is an FX lens.
Third party lens makers have their own DX/FX designations. Visit the lens makers web site to learn how they do it.

Crop sensors are physically smaller than full frame sensors.

Being smaller, more crop sensors can be made on a wafer of silicon, so crop sensors cost less on a per sensor basis.
About 4x less expensive than a full frame image sensor.

Crop sensors cannot capture as wide a field of view as a full frame sensor when both use the same lens focal length.
Lenses designed for crop sensor cameras project a smaller image circle to the image sensor.
Digital Camera Sensor Sizes How it Influences Your Photography

 

[soufiej]

Does someone mind explaining the difference?

Specifically, I just purchased a used 35mm prime and asked why they were selling and the response was that lens is for a crop body sensor camera and they moved onto full frame. This worries me because that means the lenses I have will not be compatible once I upgrade? I don't want to have to upgrade, I like the lenses I am acquiring!

Are you planning to upgrade? Any idea why you would want to upgrade? Any idea of the cost involved in upgrading? People have done quite well without full frame cameras and you probably can do likewise.

I don't want my house to get squished by a rampaging dinosaur either but I don't sit up at night worrying about it.

 

[Designer]

I think her main concern is "wasting money" on lenses that may not perform as intended IF she ever buys a "full frame" body.

lisameowrie; don't worry about it. By the time you decide to upgrade the camera, you will have bought and sold several lenses. And a bunch of other stuff.