How to Focus YOUR PHOTOS!

I agree with you, we, as a community have been pushed more and more towards numbers, have you got enough pixels in your camera? (20Mp? Is that ALL??) Is your DOF small enough (even when theres none to speak of! "M43 just cannot DO dof!") Is your dynamic range big enough? Have we got enough stabilisation in your camera ("only 3 stops? I dont get out of bed for less than 5 stops" ) how big is your iso range? ("Does your camera go up to 256,000 iso? No?? Oh you poor thing!") it just goes on and on, it's getting silly, all it is is just a device for selling more and more units! It wasnt long ago that the Canon 5D mkiii was THE benchmark for pro photographers, with a few more than 20Mp it would be laughed at these days! We have, as an industry lost the artistry in our field, it has become black and white, if your background isn't pristine then you must be an amateur! We MUST MUST MUST move back towards theart of the photo, David Bailey, an icon in the field, in my experience was very rarely what the 'influencers' (God I hate that term!describe as technically correct, but oh my God did he turn out some iconic photos! We must relearn that

Diffraction - light trips up when it goes through a small hole a bit like a drunk in a doorway.

When I'm not sure and even sometimes when I'm sure what aperture works for the landscape shot, I take a few photos with different aperture values. For example of that tree, you can just shoot f4, f5, f8, f11, f13, f22, etc. The tree won't run away and you can just delete the photos you don't like later. Or leave them and maybe you'll change your mind after some time. Digital storage these days is so cheap...

So I don't worry about focus and eat a delicious cake instead. Thank you!

As for diffraction: the usual ray tracing diagrams you're used to seeing -- of lenses bringing rays of light down to a focus -- assume that they do so perfectly, so that every point in the scene is mapped to exactly one point in the image plane. That would be ideal, but in reality, light is an electromagnetic wave, which means that it doesn't exactly always propagate in perfectly straight lines the way the ray-tracing diagram suggests. Instead what happens is that light bends around barriers, the way water waves do when passing through an opening. Rays that were initially straight and parallel are instead now spreading out slightly. The upshot of this is that, because of the finite size of the circular aperture, instead of the lens focusing rays from a single point in a scene perfectly down to a single point on the sensor, it focuses them into a circular area on the sensor. I.e. every point in your scene gets smeared out into a circular disc of non-zero size in your focal plane (called an Airy disc). The relationship between the amount of smearing (diffraction) and the size of the aperture is inverse: smaller apertures smear light out into a larger Airy disc**, while larger apertures smear light out into a smaller disc. That's why diffraction is more noticeable at high F-numbers: you've stopped the aperture down to a smaller physical size. Diffraction obviously degrades your resolution -- if every illuminated point in your scene is now a larger disc in your image, obviously these discs will all be overlapping each other, making it more difficult to distinguish two points (e.g. distant objects) as being separate from each other. But diffraction only degrades things noticably if the size of the Airy disc is larger than the size of your pixels. If the Airy disc is smaller than the pixel scale, then obviously the smearing due to diffraction does not matter, because the finite pixel scale is what's limiting the resolution in that case.

Thank you for confirming the need for cakes in my life, especially imperfect cakes.

"...I could see the tree growing!"...ya made me laugh out loud. 🙃

I'm a teacher, and I wish I was half as entertaining as you when I don't know what I'm talking about.

Hello David, I can not believe you got distracted, you covered the wet feet, the cobwebs, the ill parking of your car, I think you were right on focus point. We even covered baking. Love it when you show your photographs as a point of reference. Thanks for another great video.

I must say james, i LOVE your content! The fact that you put your true self and proccess out there instead of portraying to be another perfect landscape photographer is awesome and very relatable. Much love and blessings from New York City!!!

One of the first images that I took when I got my first dslr, nothing is properly focused and the camera shake is horrible, but it still today gets people saying "I love that one". Now, every time I see it I love that one too..because it tells a story. It took me more than a year before I understood it

Love looking back at some of your older pics and learning new things about them!

Thanks, James - taking photos of things in landscapes is an important distinction than being a landscape photographer - never really thought about that before, but that's exactly what I do and despite doing it for years, I'd never made that intellectual leap. I thank you.

After watching this video I know three things for sure: 1. Your photos are getting more and more amazing 2. Cake, just because. 3. You are not Spider-Man ;)))

I love your vids, they're mint!! The fact that you go into "ramble mode" all the time is one of the reasons. You come across as someone trying to explain to friend what's what. The info becomes more memorable...to me anyway. Some of the others (as good & helpful as they are) just feels like a teacher/student scenario. So thanks for all the advice in your videos so far, you've been a big help. Looking forward to more in the future

My day gets better every damn time you upload a video. Good stuff as usual

Thanks for focus on focusing. Very practical video for me still working on a style for me you’re thoughts help immensely

6:50 - I see that you're going for the surfer, but I love how the rock and the mountain behind it are basically the same shape.

Always enjoy your videos, thanks David

Love your videos, humor, and knowledge. Keep em comin!