However, after the Nikon 1 V3 firmware upgrade this spring, the focus issue was gone, and I found the lens to be much more usable on the Nikon 1 camera. Here is how they look when mounted. The FT-1 adapter is between the camera and lens:
Of course, I wouldn't recommend buying this lens solely for the use on Nikon 1. But if you already have a Nikon DX or FX system, you may consider sharing the lens with a Nikon 1 camera as well.
But how does it perform? Do you get any real reach benefits over using the much smaller and more portable Nikon CX 70-300mm f/4.5-5.6 (my review)? After all, if using the enormous Sigma 150-600mm Sports does not give you any more details, it is better to leave it at home and bring the CX 70-300mm. To find out this, I have compared them.
Here, I have photographed a test scene at about 40m focus distance, using various configurations. For the best image quality, I took all the images at ISO 200, on a tripod, and with 10s shutter delay to avoid camera shake. With the Nikon D3300, I used Live View for focusing, for the best accuracy, and to avoid the mirror slap vibration.
When using the Sigma 150-600mm lens on Nikon 1 V3, autofocus works well, but you are limited to using the centre spot AF detector only, and the AF-A mode is not available. Otherwise, the autofocus works quite quickly.
To make it easier to compare the image quality, here are some 100% crops from the photos (click for larger versions):
Stopping down further
It is common to note that stopping down a lens yields better quality, especially for a complicated zoom lens. So let's try. Again, I have taken a series of images using the native Nikon 1 tele zoom lens, and the Sigma lens. I used ISO 400 to keep the shutter speeds fast enough (faster than 1/1000s in this case), and of course used a sturdy tripod and shutter delay to avoid camera shake.
Here is one series of results, all the images are 100% crops from the Nikon 1 V3 camera (click for larger images):
And the other:
(Note that some of the images here were unusable due to poor technique.)
We see here that stopping down to f/8 does improve the results, quite a lot actually. So at 600mm f/8, you do get much more details when using the Sigma 150-600mm f/5-6.3 Sports lens on a Nikon 1 camera, compared with using the native Nikon CX 70-300mm lens.
But in real life, it is not easy to use f/8, as you need to push the ISO quite some. Unless you have direct sunlight.
Here are some real life example images taken at 600mm f/8 with the Nikon 1 V3, handheld. The first at 600mm, f/8, 1/800s, ISO 400:
And a 100% crop from the image:
Another example image (600mm, f/8, 1/1600s, ISO 160):
And a 100% crop:
While the pixel level sharpness could have been better, these images are certainly usable. And keep in mind that these pictures have been taken at a mindboggling 1620mm equivalent reach.
Based on these images, I think there is little extra benefit of using the Sigma 150-600mm f/5-6.3 Sports on a Nikon 1 camera beyond about 400mm. And, if you mount the lens on a DX camera, you get about the same amount of details at 600mm anyway. So why bother putting the lens on a Nikon 1 camera in the first place?
So in conclusion, I think there is little extra value in using the lens on a Nikon 1 camera, at least as long as you have a fairly modern DX or FX camera. The exception is if you are able to stop the lens further down to f/8. Stopped down, you should expect better details than when using the native Nikon CX 70-300mm lens.
You can see further image comparisons here.