DaveC1 Loc: South East US

This came up in another recent thread. And at the risk of muddying the waters I'm going to post it here as it may help explain some of the lens roll in obtaining in focus shots. Keep in mind as others have stated: On the other hand most lens at wide open apertures have optical abbreviations that make in focus photos, at least over the entire photo impossible.

https://www.cambridgeincolour.com/tutorials/diffraction-photography.htm

mcclizam

Thank you, gvarner. I've got it in Servo, which is the Canon setting for something in motion. And I'm holding the BBF button down once I've focused on him--that's correct, right? In other words, I lock focus and let go of the button for something still, and only can recompose on the same plane. With something in motion, I focus and then keep holding the button down as I follow, say, a moving dog. Thanks for clarifying.

mcclizam

Thanks, Dave. The link to that site is worth the price of admission!

DaveC1 Loc: South East US

Glad to be of service.

R.G. Loc: Scotland

Shooting at the widest aperture is what you do if you're shooting fast action in poor light - for example shooting sport indoors in artificial light. If you need to keep your shutter speed up you don't want to have to resort to very high ISOs. Shooting in bright daylight is another matter, though. You should be able to keep the shutter speed acceptably fast and use a smaller aperture as well.

It'll also increase DOF if you don't zoom in so close. Shooting slightly wide and if necessary cropping later is a possibility, provided you can stand to lose some of the resolution through cropping. 18MP should give you some leeway (unless you're after large, sharp prints). But in daylight you don't need to be using the lowest f-stop.

rdubreuil Loc: Dummer, NH USA

That is correct as to the use of BBF, held down continuous focus, focus and release for static subjects.