Focus Stacking

Regardless of the method used to take the focus stacking photos, we will first have to think about the number of sensors we will have to make for each frame, but especially with the automatic method.

Lens Focal Length
It is also absolutely necessary to take into account the chosen focal length. Indeed, a wide angle is not the same as a machine vision lens because the latter has a much smaller depth of field. We must therefore increase the number of photos to ensure that the entire landscape presents the maximum sharpness.

Rotating The Focus Ring
Another important factor, especially when using manual mode, is the angle of rotation of the focus ring.

On the lenses that come in the kits usually offered by the manufacturers, and medium / high range, designed for high speed autofocusing, the paths are very short and generally do not have focus distance scales. very precise point since the separation between one and the other is very small.

On machine vision lenses, these paths are much longer and usually have markings with much more precise distances. This is the reason why we tend to make a greater number of triggers on machine vision lenses with long focusing paths than on those that do not have as many.

Recommended Number Of Photos
Taking into account what we have seen previously, regardless of the chosen mode (manual or automatic focusing), it would be best to make as few captures as possible to have the whole frame in focus because, on the contrary, taking more pictures than necessary can cause a whole lot of problems, which we will see later, when we proceed to the final blending.

If you are using a wide angle to work with focus stacking, your best bet would be no more than three captures. If you are using standard 35-50mm focal lengths, do not take more than five or six captures. And if you are working with a machine vision lens and resorting to very open diaphragms, then here you will need to secure the shot and perform a greater number of releases to prevent the characteristic shallow depth of field of these lenses leaving no area untouched. focus on your focus stacking.

How To Make The Blending Or The Combination?
There is a set of commercial software that allows you to automatically focus stacking or focus stacking. These softwares are generally used in macro photography, they are quite complex but also relatively precise. But it’s like everything: everything good has a price, so maybe it’s better to go for a more rudimentary and easy-to-run method, on software like Photoshop or Lightroom.

That said, Adobe software still has a long way to go, stacking up on debugging issues, so we can’t recommend it for exclusive use but to use it as a starting point and then complete the process. combination in hand.

Taking all this into account, I’m going to walk you through three diferent methods and you will choose one or the other, depending on the complexity of the shot and the number of images you want to combine.

Automatic Focus Stacking Method With Adobe Lightroom
Lightroom is becoming the tool par excellence for a large number of photographers, professionals as well as amateurs, since it allows all at the same time to update a collection of photos, to develop RAW files and to operate more complex retouching without going through Photoshop.

Read more:
https://shale-world.com/2021/12/09/essential-components-in-machine-vision-system/
https://tananet.net/why-do-we-need-machine-vision-systems/
https://gotartwork.com/Blog/machine-vision-availability-of-technologies-and-main-applications/19379/
https://www.mrjourno.com/technology/machine-vision-what-it-is-and-where-it-is-applied-1639122206.html
https://www.zupyak.com/p/2802606/t/how-to-choose-a-machine-vision-camera
https://www.zybuluo.com/jklovew/note/1944542
https://bioneerslive.org/2021/12/how-many-photos-to-take-for-each-frame-with-focus-stacking.html
https://newseveryday.co.uk/things-to-know-about-machine-vision-cameras/
https://ibusinessday.com/video-analytics-and-machine-vision-from-theory-to-practice/
http://www.charrcha.com/detail/telecentric-lens-in-object-space
https://answerdiaries.co.uk/2021/12/12/the-telecentric-lens-can-be-used-to-work-with-ccds/
https://podloud.com/podcast/pietervalentineglover-s-podcast/episode-2-optical-parts-basics-lenticular-lens