Using DX lenses on FX camera: Time to upgrade my D5100 and looking a FX, but I have a lot of DX lenses and don't want to walk away from them all at once. Will my 50mm DX lens, on an FX...

acreutz

Time to upgrade my D5100 and looking a FX, but I have a lot of DX lenses and don't want to walk away from them all at once. Will my 50mm DX lens, on an FX camera, still behave like it does on the DX camera -- i.e., since it uses only about 2/3 of the FX sensor, in that context is it still a "DX lens" on a "DX camera". Is the quality as good. Could I distinguish the image between the DX lens on FX and the DX on DC?

MT Shooter Loc: Montana

acreutz wrote:

Time to upgrade my D5100 and looking a FX, but I have a lot of DX lenses and don't want to walk away from them all at once. Will my 50mm DX lens, on an FX camera, still behave like it does on the DX camera -- i.e., since it uses only about 2/3 of the FX sensor, in that context is it still a "DX lens" on a "DX camera". Is the quality as good. Could I distinguish the image between the DX lens on FX and the DX on DC?

Pretty much, yes. However there is no such thing as a 50mm DX lens. All 50mm prime lenses are FX.
Nikons FX cameras are default set to automatically switch to DX mode when a DX lens is attached, however that feature can easily be disabled allowing you to use the full sensor with DX lenses, albeit with the accompanying vignetting visible in the frame.

rmalarz Loc: Tempe, Arizona

What MT Shooter said.
--Bob

acreutz wrote:

Time to upgrade my D5100 and looking a FX, but I have a lot of DX lenses and don't want to walk away from them all at once. Will my 50mm DX lens, on an FX camera, still behave like it does on the DX camera -- i.e., since it uses only about 2/3 of the FX sensor, in that context is it still a "DX lens" on a "DX camera". Is the quality as good. Could I distinguish the image between the DX lens on FX and the DX on DC?

Cany143 Loc: SE Utah

Ditto what MT Shooter & Bob said. But I was surprised to find that my (DX) 10-20mm AF Nikkor actually covered the full FX format on my D610 --from 18 to 20mm, anyhow-- without vignetting. (There may have been some mild light fall off in the corners, but I didn't get anal enough to properly check.)

ELNikkor

I also have a D5100, and was looking to go FX, largely because the D5100 was getting "long in the tooth", and I had a lot of lenses from my film days I wanted to use on a 24x36 sensor. I chose the D750, as it was being offered with a 24-120 f4 lens and battery pack for under $2000, (which matched the amount my rewards credit card had saved), so it would be a "free" upgrade. I had imagined the D750 would offer the most versatility, as the DX lenses would work on it, it had buiilt-in flash, and a moveable screen. Although I have 18-55, and 55-200 DX lenses, I don't use them on the D750. If I put them on, there is a window which shows the area which the sensor will cover, but it is easy to forget about those lines. and compose so the subject ends up outside the frame. I've seen articles which suggest some of the DX lenses reach beyond the DX format, (specifically the 35 1.8 prime), but it is generally advised that, if you get an FX camera, you find a way to get FX lenses to use on it.

acreutz

Hadn't thought of that issue! Will want to see how it looks. I do lots of flowers, and then landscapes. For both framing is important.

CO

You'll also be throwing away a lot of pixels by using a DX lens on an FX full frame camera. For your flower and landscape shots, you might want to get an upgraded DX camera and keep using your DX lenses. The D7200 is heavily discounted right now to $696 since it's going to be discontinued soon. It's still an incredible camera. The D7500 is another camera to look at. You could go for the ultimate DX camera and get a D500. I have one. It's an incredible camera. I use my full frame D750 mostly for shots where I'm looking for a shallow depth of field.

camerapapi Loc: Miami, Fl.

Your best bet is to buy another DX body. It makes no sense to buy a FX body to use DX lenses.

joer Loc: Colorado/Illinois

acreutz wrote:

Time to upgrade my D5100 and looking a FX, but I have a lot of DX lenses and don't want to walk away from them all at once. Will my 50mm DX lens, on an FX camera, still behave like it does on the DX camera -- i.e., since it uses only about 2/3 of the FX sensor, in that context is it still a "DX lens" on a "DX camera". Is the quality as good. Could I distinguish the image between the DX lens on FX and the DX on DC?

Some optical characteristic of a lens are linked to the pixel count of the camera. As an example resolution
would be lower when the cropped image from a FF camera has a significant lower pixel count.

Would you see the difference?...it depends on how big the difference is and how large you view or print the images.

paulrph1 Loc: Washington, Utah

acreutz wrote:

Time to upgrade my D5100 and looking a FX, but I have a lot of DX lenses and don't want to walk away from them all at once. Will my 50mm DX lens, on an FX camera, still behave like it does on the DX camera -- i.e., since it uses only about 2/3 of the FX sensor, in that context is it still a "DX lens" on a "DX camera". Is the quality as good. Could I distinguish the image between the DX lens on FX and the DX on DC?

My FF camera has a setting of being able to use the camera as FX or DX. But I only shoot FF because that is what my lenses are. Nikon D 750.

BebuLamar

acreutz wrote:

Time to upgrade my D5100 and looking a FX, but I have a lot of DX lenses and don't want to walk away from them all at once. Will my 50mm DX lens, on an FX camera, still behave like it does on the DX camera -- i.e., since it uses only about 2/3 of the FX sensor, in that context is it still a "DX lens" on a "DX camera". Is the quality as good. Could I distinguish the image between the DX lens on FX and the DX on DC?

In general using DX lenses on an FX camera makes it not as good as a DX camera. I don't think there is a 50mm DX lens.

mborn Loc: Massachusetts

DX lenses on a. DX Body and vice versa but you can use either/or on both bodies

bkwaters

If you want a mirrorless camera, there's nothing wrong with getting the Z6 or Z7 and using DX lenses on it, especially for macro and telephoto. You lose pixels, so will need to limit excessive cropping or very large prints, especially on a Z6. In my opinion this is a great advantage of shooting Nikons. The DX lenses also match well with the smaller size of the Z-bodies.

PHRubin Loc: Nashville TN USA

acreutz wrote:

Time to upgrade my D5100 and looking a FX, but I have a lot of DX lenses and don't want to walk away from them all at once. Will my 50mm DX lens, on an FX camera, still behave like it does on the DX camera -- i.e., since it uses only about 2/3 of the FX sensor, in that context is it still a "DX lens" on a "DX camera". Is the quality as good. Could I distinguish the image between the DX lens on FX and the DX on DC?

It turns out that cropping an FX by 1.5 (the crop factor of DX) does not leave 2/3 of the pixels. It cuts by 1.5 both in width and length. So 1/1.5/1.5=0.44, or les than half.
Alternately an FX sensor is 864mm²
A DX sensor is 380mm²
380/864=0.44

acreutz

Thanx to all. PH, you actually addressed one of my questions whether a DX lens on an FX camera would really be "equivalent", and, your math shows it clearly is not.
I think I am back to the 7200/7500 decision...