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Image quality of a prime long lens worth it? (1 Viewer)


Well-known member
United States
Hello, I have a Nikon Z7 (I love it) and use a Nikkor 200 - 500 lens with an FTZ converter, as the lens is a F mount. The rig is very heavy, and the converter slows my frame rate. So I'm considering getting a prime 400mm, since almost everything I shoot is at 500. Question is, will the better image quality enable me to crop more, and reach farther before the edges start getting blurry? Also, is there generally better AF performance? My full frame sensor is 45 mp, and I usually shoot as wide open as lighting will allow. Thanks for any input!


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I shot with the 200-500mm lens on my D500 camera and later the D850. The 500mm PF was a tremendous upgrade in terms of autofocus performance, VR performance, and image quality. The 500mm PF is nearly 2 pounds lighter than the 200-500mm zoom.

I sold my 500mm PF and it was a mistake as this lens works very well with the FTZ adapter. I replaced it with the 400mm f/4.5 and the 1.4x teleconverter to have a 560mm f/6.3 lens setup. It is an expensive way to gain an additional 60mm of focal length. One can buy a used 500mm PF from its current owner on fredmiranda for less than $1800.

I am hoping that Sigma will release a Z mount version of their 60-600mm OS lens. Owners with the version for Sony mirrorless cameras are very positive and report being able to shoot video hand held.
Although not Nikon, I have a 500mmf4LIS prime and it is a superb piece of glass and is very capable, whether or not one will enable you to crop more I don't know, but if you get one I don't think you'll be disappointed.

Also, 500mm Tele Primes are superb at producing really good backgrounds.

Taken with a 500mmf4LIS + 1.4TC

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Superb capture! Barred owl? I'm trying to get a sense of how far I can reach with a 400 prime, and maybe a teleconverter ($$ sigh)..
Here are a few photos I just took to test for you
All taken with a canon camera with a 400mm prime lens

The closest was 5m away from the 'dog', then 8m then 10m
The dog is approximately 150mm from top of the head to bottom of the paw.
Hopefully that's helpful!
*Edit - please note that the image quality could be better, but I was doing it more to show the reach of the lens rather than the quality!


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Hello, I have a Nikon Z7 (I love it)...

The Z7 has a low frame rate and shooting wide open doesn't necessarily optimise image quality. If you're serious about bird photography I'd buy gear specifically for that job - a DX (APSC) camera of about 20mpx (Canon 7DII is still a great sports/nature camera) to 'multiply' your lenses by 1.5/1.6x, and invest in the best prime lenses.

I'm yet to be convinced that 'lots of pixels' are as good as 'really good pixels'. In fact, when retiring from photography as part of my work, I went the other way - my Fuji mirrorless XT1 is only 16mpx (and still going strong), but the sensor produces finer detail than the 36mpx Nikon D810... go figure, as they say. I had them side-by-side for a while, after retiring, and sold the Nikon.

Mikbul's superb images (#2/3) are from a Canon 40D - 10mpx!!! - at f5.6 and f8. Certainly, for screen resolution and photo-prints of up to 2ft across, anything over 24 megapixels are a waste... IMO. Sorry!
I would look at the pf500 its a cracking lens . its so light .
the af will be approx twice as fast as your 200-500 . reach is everything for bird photography.
400mm is a bit on the Short side
have a look at Steve Perry on you tube he has tested most of the Nikon Primes side by Side.
I now have a 5D markiii and a 7Dmarkii. Here's a shot with the 5D and Canon 300L IS. In the future I'll be using the 7D with that lens (1.6X crop factor) 217.JPG

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