Nikon Z 100-400mm f/4.5-5.6 S vs Tamron 70-300mm f/4.5-6.3

Partly for fun – and partly to see if you get what you pay for – I wanted to compare two rather different telephoto zooms today. One of them is among Nikon’s most coveted professional lenses, the Z 100-400mm f/4.5-5.6 S; the other is a third-party optic that costs about 1/3 as much, the Tamron 70-300mm f/4.5-6.3. Which lens wins? Well, that’s not going to be a surprise, it’s the Nikon. But by how much? That’s what I’ll cover below!

Focal Length (and Related Considerations)

Starting with the obvious, these two lenses have different focal length ranges and different maximum aperture values at each focal length. For most photographers, reaching to 400mm on the long end will be more helpful than reaching to 70mm on the wide end, especially if you have other lenses that already cover 70mm.

In terms of maximum aperture, the Nikon lens has about a 1/3-stop advantage at 100mm and about a 1/2-stop advantage at 300mm. It’s nothing major, but still a win for the Nikon lens. You can also add a teleconverter to the Nikon Z 100-400mm f/4.5-5.6 S to extend your reach, while the Tamron 70-300mm f/4.5-6.3 is incompatible with Nikon’s teleconverters.

Lastly, the Nikon Z lens has vibration reduction built-in, while the Tamron doesn’t. That’s not a big negative for Tamron so long as your camera has in-body image stabilization. However, if you intend to use this lens with any Nikon Z camera without IBIS, you’ll be much better off with the Nikon Z 100-400mm.

Size and Weight

Unsurprisingly, the Nikon Z 100-400mm f/4.5-5.6 S is a much larger and heavier lens than the Tamron 70-300mm f/4.5-6.3. However, until you’ve held both of these lenses, the degree of difference might be difficult to understand.

I’ll put it this way – even with its tripod collar removed, the Nikon lens is 2.5 times as heavy as the Tamron lens. And the size difference feels even greater. Here’s a rough comparison, to scale, of both lenses:

When I was testing these two lenses in the field, the Tamron was easy to throw in my backpack (or just handhold) with barely a second thought. As for the Nikon lens, it’s not like it stayed in my bag the whole time, but carrying it around all day was a lot tougher. You don’t need a tripod when you’re using the Nikon Z 100-400mm f/4.5-5.6 S, but you’ll probably want one.

Some photographers may prefer the reassuring heft of the Nikon lens over the lightweight feel of the Tamron, but if I had to bring either lens on a long hike, I know which one I’d reach for.

Build and Handling

There’s no contest here – the Nikon Z 100-400mm f/4.5-5.6 S is a pro-level lens with excellent build quality and handling features. I was actually impressed by the Tamron lens’s build quality and weatherproofing, but in terms of handling, it’s terrible by comparison.

The Nikon Z 100-400mm has a multitude of buttons and switches – two function buttons, an extra control ring, a focus limiter, an illuminated display, and an A-M switch. The side of the lens looks like this:

Meanwhile, the Tamron lens doesn’t have any buttons or switches at all – not even an A-M switch. There’s just the usual focus and zoom rings. Of course, that’s part of how Tamron got the weight and price down, so some photographers won’t care one way or another.

Both lenses extend when zoomed, with a single barrel telescoping design. This isn’t ideal for working in rainy or dusty conditions, but the sealing on both lenses never gave me any problems even in harsh weather.

Image Quality

1. Distortion

Telephoto lenses aren’t known for having high levels of distortion, but the Tamron lens does get higher than I’d like to see. Here are my distortion measurements for both lenses:

The Nikon lens maxes out at 1.95% pincushion distortion, while the Tamron lens reaches as high as 3.14% pincushion distortion. This is usually easy to correct in post-processing regardless, but it’s still a win in the 100-400mm f/4.5-5.6’s column.

Lateral Chromatic Aberration

Neither lens has high levels of chromatic aberration at the wider focal lengths. Unfortunately, the Tamron 70-300mm f/4.5-6.3 jumps sharply in CA at 300mm. Here are the full charts:

Both lenses achieve very good performance levels in the shared range from 100-200mm. I’m not sure why the Tamron lens spikes so high at 300mm by comparison. Meanwhile, the Nikon Z 100-400mm f/4.5-5.6 S has its own spike at 400mm, but it’s still less than the Tamron. Adding a teleconverter to the Nikon 100-400mm increases chromatic aberration further, unsurprisingly.

3. Vignetting

Now let’s take a look at vignetting – another area where the Nikon Z lens comes out ahead:

I wouldn’t call the differences striking, but they definitely favor the Nikon Z 100-400mm f/4.5-5.6 over the Tamron 70-300mm f/4.5-6.3. At 100mm, wide open, it’s about a 0.3-stop difference. That difference jumps to about 0.4 stops at 200mm and 0.5 stops at 300mm.

4. Sharpness

Now for the real fun! Does the Nikon Z 100-400mm f/4.5-5.6 continue its winning streak by being sharper? In a word, yes.

Here’s 100mm, the first shared focal length of these two lenses:

This really is no contest, regardless of where you look in the frame. The Nikon Z lens is much sharper at 100mm, from the center to the corners. It’s not that the Tamron lens is bad (although its corners aren’t great at 100mm) – it’s more that the Nikon lens is unusually good. The differences narrow a bit, but never equalize, at f/11 and f/16.

Now for 200mm:

This time, the Tamron lens’s corners have improved significantly, while the Nikon 100-400mm is not quite as sharp as it was at 100mm. But that’s not enough to change the story; the Nikon lens is ahead at every aperture and portion of the frame.

Lastly, here’s 300mm:

If you’ve read my Nikon Z 100-400mm f/4.5-5.6 S review, you may recall that it weakens a bit in sharpness at the longer focal lengths. The Tamron also maintains very good performance at 300mm, unlike a lot of third-party lenses. Even so, the Nikon lens is significantly sharper wide-open, and it’s sharper in the corners at every aperture. At the narrower apertures, the Tamron 70-300mm f/4.5-6.3 does manage slightly better central and midframe performance.

Overall, I think the answer is pretty clear – you do get what you pay for with a pro-level Nikon Z lens. The Nikon Z 100-400mm f/4.5-5.6 S is a vastly sharper lens than the Tamron at 100mm and 200mm, and it’s still the better performer at 300mm (although less dramatically). The Nikon lens also comes out ahead in distortion, vignetting, and chromatic aberration. It’s simply a better-corrected lens, as it should be for the price and weight.

Value

These two lenses live in very different worlds. Frankly, it’s unfair of me to compare them under a microscope optically, with the $700 Tamron doomed to lose to the $2700 Nikon S-line lens.

But seeing the differences like this side-by-side lets you get a good sense of each lens’s value. If you’re on a budget, I would get the Tamron, no contest. The same is true for any lightweight situations. As a landscape photographer who likes to hike long distances, the Tamron 70-300mm f/4.5-6.3 is immediately appealing because it still manages solid performance without breaking my back. With Tamron’s usual $100-off sale, it makes for a very good value.

Still, considering the Nikon’s impressive performance (and 400mm capabilities), it’s also a good value. They’re just made for different audiences. Professional photographers who want excellent performance and maximum versatility, even at the expense of weight and price, can’t go wrong with the Z 100-400mm f/4.5-5.6 S.

You can check the current prices, and support my testing efforts at Photography Life, at the following B&H affiliate links:

• Nikon Z 100-400mm f/4.5-5.6 S at B&H – Check prices and current sales
• Tamron 70-300mm f/4.5-6.3 for Nikon Z at B&H – Check prices and current sales

Conclusion

I hope this article helped you decide which one of the two lenses is right for you – or justify the purchase of whichever one you already have :)

The truth is that the Nikon 100-400mm f/4.5-5.6 is optically fantastic, while the Tamron 70-300mm f/4.5-6.3 performs well for a lens that’s 1/3 the price and less than 1/2 the weight. Even though this comparison has a clear winner, neither lens is a bad choice. They’re just made for different photographers.

Let me know in the comments if you have any questions about these two lenses, and I’ll do what I can to answer!