WEBVTT

00:00:00.320 --> 00:00:06.080
now it used to be that back in the time of the dinosaurs when a person set out

00:00:03.679 --> 00:00:09.639
to take a photograph specifically a not blurry one they would actually have to

00:00:07.799 --> 00:00:13.120
send their assistant out with one end of a measuring rope and then adjust their

00:00:11.320 --> 00:00:16.039
accordion lens to the proper focal distance I mean okay that's a bit of an

00:00:14.519 --> 00:00:20.359
exaggeration but I think you guys get it what I'm driving at here autofocus

00:00:18.640 --> 00:00:25.519
Optical systems like all things photography related are complex and lead

00:00:22.920 --> 00:00:30.000
to the necessity of many highly priced peripherals and accessories or to put it

00:00:28.000 --> 00:00:34.200
a gentler way there are many types of autofocus systems which can be employed

00:00:32.239 --> 00:00:38.800
depending on the necessity or manufacturer specifications thankfully

00:00:37.040 --> 00:00:44.559
these multiple types can be broken down into two very simple camps active and

00:00:41.879 --> 00:00:48.719
passive passive systems come in several different forms but all operate by

00:00:46.520 --> 00:00:53.960
analyzing an image once it has been projected onto one or more sensors then

00:00:51.800 --> 00:00:57.520
adjusting the focus based on the qualities which help it to determine

00:00:55.480 --> 00:01:02.280
subject distance or Clarity since they only respond after an image has already

00:00:59.760 --> 00:01:06.400
been captured and then make adjustments without using environmental data all

00:01:04.559 --> 00:01:10.840
processes they enact are considered passive they are mostly found in two

00:01:08.920 --> 00:01:16.240
basic varieties which are referred to as phase or contrast detection phase

00:01:13.840 --> 00:01:20.680
detection can be found commonly in DSLR style cameras and works by using an item

00:01:18.720 --> 00:01:24.960
called a beam splitter to direct the light from an incoming Source onto two

00:01:23.119 --> 00:01:29.000
separate micro sensors which are placed on opposing sides of the lens

00:01:27.000 --> 00:01:33.479
effectively doubling the image doubling the image doubling the image in older

00:01:31.000 --> 00:01:38.479
cameras the user would manually have to adjust the focus until both images came

00:01:35.560 --> 00:01:43.240
in line but today software is utilized that matches up light intensity patterns

00:01:40.759 --> 00:01:48.360
based on Peaks and valleys allowing it to make a determination about whether

00:01:45.040 --> 00:01:51.159
the subject is back or out in front of

00:01:48.360 --> 00:01:55.240
proper Focus now while phase detection works well on high quality cameras with

00:01:53.320 --> 00:02:00.320
interchangeable lenses the added cost and bulk that accompanies it does not

00:01:57.880 --> 00:02:06.039
always make it a feasible option which by contrast brings us to well contrast

00:02:04.079 --> 00:02:10.479
detection that is at least this form of focusing works by analyzing the pixel

00:02:08.319 --> 00:02:14.879
intensity of an image on the sensor automatically adjusting slightly past

00:02:12.800 --> 00:02:18.920
the point of highest contrast and then back again this is what causes that

00:02:16.920 --> 00:02:23.879
quick blur effect that you might have seen on your viewfinder before snapping

00:02:21.200 --> 00:02:27.000
a shot but lonus I thought you said that there were two different camps of

00:02:25.120 --> 00:02:30.840
autofocus what about that that active thing you mentioned before well yes I

00:02:28.560 --> 00:02:35.680
did say that but in reality it was actually a bit of a tease since

00:02:33.200 --> 00:02:41.239
applications of active autofocusing tend to be on the less than practical side so

00:02:38.160 --> 00:02:43.120
far these devices work in theory by

00:02:41.239 --> 00:02:47.599
physically measuring the distance between it and the subject and operate

00:02:45.560 --> 00:02:52.159
outside the normal functions of the optic system so two implementations of

00:02:50.200 --> 00:02:57.040
this focusing style have been seen so far sonar which uses audible clicks to

00:02:55.239 --> 00:03:02.680
determine the distance to the subject yes just like dolphins do or infrared

00:03:00.040 --> 00:03:06.920
lasers like the one found on the LG G3 smartphone these use a constantly

00:03:04.920 --> 00:03:11.120
measured distance to triangulate the space between the subject in the camera

00:03:08.319 --> 00:03:16.360
and adjust the focus quickly on demand these systems have uh you know some

00:03:14.280 --> 00:03:20.040
failings though such as you know functionality ones like the inability to

00:03:18.280 --> 00:03:23.640
work when shooting something underwater or through a window and more mundane

00:03:22.239 --> 00:03:28.560
ones as well like the annoyance of having your camera click every time you

00:03:25.840 --> 00:03:31.640
take a picture while active Focus can still be considered in the EXP

00:03:29.760 --> 00:03:35.760
experimental stage it seems for the most part the verdict is still out so whether

00:03:33.720 --> 00:03:39.640
you're shooting you know 4K footage of your self performing reviews of latest

00:03:37.959 --> 00:03:43.400
computer components or taking pictures of someone pushing a hoop down a dirt

00:03:41.080 --> 00:03:47.519
road with a stick autofocus has what it takes to keep you in the clear speaking

00:03:45.760 --> 00:03:52.840
of annoying clicks if you're just finding your current job is not clicking

00:03:51.000 --> 00:03:59.159
for you and you want to keep your future career prospects open then maybe give

00:03:56.239 --> 00:04:03.799
linda.com a try they want to expand your mind on a variety of subjects it's used

00:04:02.159 --> 00:04:08.159
by millions of people around the world they've got more than 3,000 courses

00:04:06.560 --> 00:04:13.280
available with topics like web development uh visual design business

00:04:11.239 --> 00:04:17.479
coding software training like in Excel WordPress and Photoshop which leads us

00:04:15.159 --> 00:04:20.479
to they also have photography courses I mean if you're watching this video who

00:04:18.759 --> 00:04:24.199
knows you might have a somewhat of an interest in photography and Photoshop

00:04:22.520 --> 00:04:27.960
all their courses are taught by industry experts with new courses added every

00:04:25.800 --> 00:04:32.120
week so whether you're setting you know you know new goals for yourself to just

00:04:30.120 --> 00:04:36.320
you know improve for the sake of you know tying that measuring tape around

00:04:34.320 --> 00:04:40.039
your bicep and seeing a bigger number okay they don't necessarily have courses

00:04:38.000 --> 00:04:42.680
on linda.com for that but the point is if you're just trying to improve

00:04:41.039 --> 00:04:46.160
yourself or if you're specifically trying to go out and get a new job

00:04:44.160 --> 00:04:50.960
linda.com has something for everyone and you can get a free 10-day trial by

00:04:48.000 --> 00:04:55.320
heading over to linda.com tequi and signing up now you can use linda.com on

00:04:53.479 --> 00:05:00.440
your computer on your iPhone on your Android device and plan start at only

00:04:57.000 --> 00:05:01.600
$25 a month so what are you waiting for

00:05:00.440 --> 00:05:05.479
speaking of things what are you waiting for press like if you're not waiting to

00:05:03.720 --> 00:05:08.880
press like or you already pressed like well don't press it again if you pressed

00:05:06.720 --> 00:05:12.560
it press dislike if you hated this video leave a comment if you have suggestions

00:05:10.039 --> 00:05:16.039
for future fastest posses and as always Mash that subscribe button if you

00:05:14.440 --> 00:05:21.080
haven't already we are getting frighteningly close to that 500,000

00:05:18.120 --> 00:05:21.080
subscriber mark