The MISCONCEPTION of Variable Aperture Lenses 

That’s why I’ve said we need a 10-600mm lens with constant aperture of F1.4 all along, problem solved 😉😂

This is probably the most comprehensive video on aperture I've seen and the visuals were very good too.

Very clear explanation, and I learned something about that continuous change. It makes perfect sense.

Welcome to the wonderful world of analog to digital conversion, where there's always a threshold but it's not always true. (Some idiot will slag me on this just as they did on my last comment re the Tamron.)

And I thought I knew all about lenses and apertures yet you taught me something new and really useful. Great job 👍

I remember reading over a forum discussion recently, where people were complaining about one particular fuji lens (can't remember which one it was) which actually does get darker abruptly at certain focal lengths while zooming. So I guess that lens is mechanically stepping down its aperture for whatever reasons

Brilliant explanation of zoom v aperture. Thanks. I understand it.

Brilliant video Dave. This makes this one of my favourites for future reference.

Great video, gave the answer to the very question I had. Thank you

Thanks! In combination with your other video about constant aperture lenses, this is really interesting!

Great technical explanation...👍👌

That's REALLY great content, thanks!

Actually well done. Ty

i thought this is common knowledge that every photographer should learn, it's really just a simply understanding of how the f-numbers work

Intresting 🤔 this changes how I’ll work with these lenses

So my question is, does iris magnification affect depth of field?

Toward the end of the video, I was having cross eyes.

Excellent!

So that's why the Nikon 200-500 has a fixed aperture and the Tamron and sigma 150-600 lenses have a variable aperture.

This is why i use prime lenses

I concur

Can I have that fur baby? LOL Thanks for the tutorial.

Ok now that we are done with telling this in Greek can we get the English version now? Just kidding. I understood what you are saying. Lol.😁

So the bottom line I really wanted to confirm is, it's still better if you can afford it to get a constant aperture zoom lens if you want to keep a shallow depth of field and good low light performance (without having to raise ISO), even at telephoto focal lengths. Right?

#1 Variable Aperture Lenses is a misnomer. They are better called Variable Aperture Cap Lenses. That is the maximum aperture is capped at a different value depending on the focal length the zoom mechanism is on. At any other aperture the aperture does not actually change. A 3.5~6.3 lens can be set at F8 and will always stay at F8. If you set it to 3.5 there is a possiblity of it being pushed to 6.3 as you zoom, but once it is at 6.3 it stays there. #2 Historically there were a few zoom lenses where by the zoom mechanism does not vary the aperture diaphragm when hence the effective aperture changes constantly regardless of the aperture set with the zoom factor. ZERO modern lenses work that way.

Dave, after your conscience explanation of the f stop, rusty look toward you as a god! Great video.

That's very interesting, Dave and I am going to check it out on my Tamron 28-200 . Here's a thought, instead of going after the same sponsors as all the other photography RU-vidrs ( Skillshare, Squarespace, et.al.) , use one of your best "assets," in Rusty, and get a pet -related company on board. Rusty is a 'natural' and definitely drives more views to your channel but I do learn a lot more from you, ha,ha!

So, basically, the light sensor has amazing resolution, and the aperture control...doesn't.

Is there a way to make the d3200 iso noise on video a less terrible?

My Brain didn’t explode 🤯 so I think I got it.

Ta

Dave ,you are talking about hardware limitations as in the old days when lenses or apertures were just what they seemed to be.Nothing more. Have you thought about the possibility that the manufacturer can limit the capabilities or the specs just by tweaking the soft ware so they tweak a camera model a little bit worse than a top model only by altering its soft ware? Like in the days of pc-manufacturing when they only tweaked the clock frequency instead of changing hardware? It would be much cheaper.

Use cinema lenses with clickless aperture rings and t stops. Problem solved.