eBay Nikon G vs Nikon AI to Canon EF mount adapter

I wrote previously about my experience with a cheap Chinese Nikon G to Canon EF mount adapter to allow using Nikon mount lenses without an aperture ring on Canon DSLRs. You can read that post here: Notes on the Canon 5D MkII, with Nikon G to EOS adapter and Tokina 10-17mm fisheye.

Since I was happy with that adapter, I bought a Nikon AI to Canon EF mount adapter from the same seller. I wanted to use the AI adapter on my Nikon 50mm/1.4 D lens (which has an aperture ring), and keep the G adapter on my Tokina fisheye. The G adapter does work on both lenses, but swapping the adapter between the lenses each time you want to change lenses is quite inconvenient. So an adapter for each lens made sense.

Nikon 50mm f1.4 D lens with Nikon AI to Canon EF adapter

When I received the AI adapter, I noticed that the 50mm lens could be focused past infinity with the adapter. So I decided to test the AI adapter against the G adapter.

The G adapter is for sale on ebay as Nikon G AF-S AI F Lens to Canon EOS EF Mount Adapter 600D 550D 1100D 60D 7D 5D (item #120870176419) from the seller phoebe-g. It cost me £15.99, plus I had to buy and add an EMF (dandelion) chip.

The AI adapter is for sale on ebay as AF Confirm Nikon Lens to Canon Adapter 60D 600D 550D 7D 500D 1100D T3i T2i T3 (item #110834720976), again from the seller phoebe-g. I paid £9.99, and this includes a chip fixed at 50mm/1.4.

With the AI adapter, I purchased it with the the chip attached. I didn't mind that the focal length and aperture was fixed, since this was correct for the lens I wanted to use it with. However, when I received the adapter, I found that you can't change the aperture on the camera at all.

There are two reasons why you might want to change the aperture on the camera:

1. To record the shooting aperture in the image EXIF
2. To preview the correct exposure when using liveview with the lens wide-open to set critical focus

Neither of these are really bad problems for me, but I would like to have the ability to set the aperture on the camera available. The chip I purchased to use with the G adapter does allow this.

The other problem is that the liveview preview is often really dark. I use liveview for focusing, so this is annoying for me. I think this must be down to the chip included with the adapter as well. This means that:

1. I can't preview the exposure accurately.
2. To focus I have to set a low shutter speed (to make the display bright enough to see properly), and then set the shutter speed to what I want after focusing. Alternatively I have to switch liveview mode to 'Stills Display' mode when using the lens, and can then switch back to 'Exposure Simulation' mode when using other lenses. Either way is inefficient and annoying.

If you are thinking of getting one of these adapters, I would suggest getting one with a programmable chip. Or get one with no chip, and then buy and add the programmable chip yourself.

Nikon AI to Canon EF vs. Nikon G to Canon EF mount adapters infinity test

I tested the two adapters against each other to see how they compare with regards to infinity focus on my Nikon 50mm/1.4 D lens. (This test was actually done in June if you're wondering why the wheat in the photo is green).

I took two photos using the lens with the AI adapter - one at the infinity mark on the lens, and one manually focused using liveview so that infinity appeared in focus in the centre of the image. Then I took one photo using the lens with the G adapter, with the focus set to the infinity mark on the lens. If you would like to compare these images yourself, you can download the RAW files here: MG_9677-9.CR2.zip (73.1MB).

Image showing where crops come from

Centre top crop

Nikon AI to Canon EOS adapter, lens at infinity mark

Nikon AI to Canon EOS adapter, lens manually focused

Nikon G to Canon EOS adapter, lens at infinity mark

Centre lower crop

Nikon AI to Canon EOS adapter, lens at infinity mark

Nikon AI to Canon EOS adapter, lens manually focused

Nikon G to Canon EOS adapter, lens at infinity mark

Crop near right edge

Nikon AI to Canon EOS adapter, lens at infinity mark

Nikon AI to Canon EOS adapter, lens manually focused

Nikon G to Canon EOS adapter, lens at infinity mark

From this test we can see a number of things. First, the AI adapter is too thin, so the lens focuses further away at infinity than it should. Secondly, the G adapter seems slightly too thick, with the lens at the infinity mark, focus is a bit in front of infinity.

The Nikon 50mm/1.4 D lens also exhibits field curvature, as the sides of the image are more in focus when the lens is set to infinity on the AI adapter than the centre of the image is. (Both sides are equally in focus so it is a curved field of focus, not a slanted field of focus).

Although the Nikon G to Canon EF adapter is slightly too thick with the Nikon 50mm/1.4 lens, it seems to work okay on my Nikon 70-300mm/4.5-5.6 G lens. On this lens infinity seemed to be in the middle of or just before the middle of the infinity mark (the lens actually focuses past infinity).

Infinity focus is achieved correctly on my fisheye lens with the Nikon G adapter. But depth of field is so large that an adapter would have to be quite out of tolerance for infinity not to be achievable on this lens.

Unfortunately, since the 70-300mm lens is a G lens, this meant that I couldn't test the AI adapter on it to see how it compared. The 50mm/1.4 D is the only lens I own that the AI adapter can be used with.

Conclusion

The Nikon G to Canon EF mount adapter I purchased works fine on my G type lenses (Tokina 10-17mm fisheye and Nikon 70-300mm VR). However, it doesn't work so well with the 50mm D type lens as it cannot achieve infinity focus.

The Nikon AI adapter allows infinity focus with the 50mm D lens, but the dandelion chip on the adapter is rubbish. If you are looking to purchase a cheap Nikon F mount to Canon EF mount adapter, I would recommend purchasing an unchipped one. You can always install a good chip yourself if you want (though it's not particularly easy to get the positioning right).

I also recommend purchasing some spare Canon rear lens caps from ebay. That way you can leave the adapter attached to the lens, and screw on the Canon rear lens cap to protect the lens' rear element.