The equivalent focal length of Tuli 16-50 on APS is 24-75 (Canon 25.6-80mm).
Wide angle is an obvious gap every mm.
If you care about wide angle, it's still 16-50.
Tully doesn't have a body motor, so it can't be used on Nikon D40.
Few people are equipped with two cameras with the same focal length at the same time, so there is almost no personal sample comparison. Generally speaking, Longteng 17-50 is better, because the dispersion is more serious at large aperture.
by the way
Do more homework before buying a lens. It is best to take the camera to the second-hand market. Under the same parameters, shooting the same scene with different apertures has its own understanding. Other people's opinions are all references.
It is very important to know the familiarity and skills of using the lens. As long as you like, you can buy any lens and use it to the extreme. More good films are good shots.
Good luck.
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Answer supplement:
7D quasi-professional, professional, regardless of technology and price, catching up with 5D2, accurate, 1.6 times focal length conversion shows that Canon photosensitive element is smaller than any APS-C camera on the market, including Nikon and pente.
Ax, any entry machine of Sony.
The choice of frame is more important than anything else. 120 is far superior to any 135, and Quan Huafu is far superior to any APS-C.
That's all nonsense.
It is recommended not to choose either. If you want to go to the factory, you have to go to the factory 24-70 mm F2.8. Well, lens input is a big deal. If you invest in a bunch of aps-c lenses, how can you upgrade 5D2 and 5D3 in the future?
The future lens planning should be 5D2 with 24-70mm, 7D with Xiaobai or Guo Xuwei, plus a head.
Women are afraid of marrying the wrong man, men are afraid of entering the wrong line, and cameras are afraid of standing in the wrong team.
The above is for reference