Autofocus lenses and Crop Factor/ Equiv

[Purduephotog]

I'm not looking for the right things, apparently, as I'm only finding very small zooms. I was looking for any autofocus lens to see what's out there. Any pointers to where they're sold?


Second question:

Right now I have a 50mm (6.7 FOV) on the camera, but wanted to check my math. I used to know all this.

Image sensor format - Wikipedia

en.wikipedia.org

So if I have a 50mm on a 1/2.8 sensor, that's equiv to about a 400mm on a full frame 35mm.

However if I put my 50mm from my 35mm camera onto a 1/2.8 sensor, then I'll have about a 50mmx7 crop factor to be about 350mm. Right?

 

[alastairstevenson]

I was looking for any autofocus lens to see what's out there. Any pointers to where they're sold?

I've had some lenses from the Aliexepress Treeeye store that I've been happy with.

Then there are the choices on all of Aliexpress

- Buy with free shipping on AliExpress

Quality with free worldwide shipping on AliExpress

s.click.aliexpress.com

 

[Purduephotog]

I did buy my 50mm from them- they sent one with an IR filter, so a little 'snip snip', crunch and crackle later.... it was removed.

I'm still looking for a 7.6mmx7.6mm IR PASS filter; I found an 8mm, but I don't know of any mounts that would fit that.

So I slapped an IR-only (850nm bandpass) over the camera. Now I have IR during the day, and during the night.

Now... the auto exposure sucks, and the manual exposure sucks, and.... sigh.