00:00          On today's show, we're going to talk about how totally mechanical manual contactless lenses work when you're shooting with mirrorless cameras.

00:15          Good morning, happy Monday and welcome to PhotoJoseph's Photo Moment; the first live three times a week show here youtube.com/photoJoseph talking about all things photography video, occasionally live streaming and uh, yeah, kind of anything related to that. Today we are talking about shooting with totally mechanical lens is a lens that has no contacts on it, no communication between the Lens and the camera. And the reason we're doing this is this had come up in a, uh, in the comments a while ago, someone was asking about how does the camera know what aperture the lenses set to when it can't communicate? And it was a question that at first kind of confused me, but then I realized, oh, this is. This thought process has probably evolved from shooting with mirrored cameras and not really adapted to mirrorless. So here's the deal. When you're shooting with a mirrored camera, your standard Dslr, the the camera doesn't know what the aperture is unless the lens can tell it or until the time of exposure, right when the mirror flips up in the sensor can read the actual exposure.

01:14          The reason for this is the meter that you're looking, that is metering. The scene on a mirrored cameras Dslr, is Miri is metering. Sorry, with the aperture wide open, right when you on a mirrored camera. If you adjust the aperture on a electronic lens, so forget the Mechanical Lens for a moment and just the a little electronic lens. The aperture doesn't actually close down, right? The the aperture never changes in the lens itself. You look through the lens and you rotate it. It doesn't actually change when you press the button to take the picture. Then the see will close down. If you've had it set to close down, it'll close down and open back up again and it does that for the actual exposure, but the lens is communicating to the Camera, Oh, I'm at f/5.6, I'm at f/8 to f/11, whatever it is, and the camera goes, okay, given the amount of light coming in, when we go to f eight, the math means that there'll be this much less light and so the exposure has to adjust this way.

01:59          So if you're shooting in say aperture priority, then the shutter speed is going to change to this or if you're an auto iso, the ISO is going to have to change to that and, and the camera meters that does the math and it's obviously all instantaneous. It does the math and makes the adjustment where else it needs to on a. If you were to then take a lens like this, he totally mechanical and put it onto a mirrored camera. The Lens, the camera has no idea what the aperture set too. So when the shutter opens and suddenly there's a hole this big, instead of this big, the cameras like, Oh crap, I have no idea what to do. You end up with an underexposed picture, which is why you generally are going to have to shoot manual when you're shooting. That way when you should've gotten a mirrored camera with a mechanical lens, but on mirrorless because there is no mere hence the name.

02:41          The sensor is constantly seeing the actual light coming through. When you close down the Lens, the amount of light coming into the lens reaching the sensor is restricted and the sensor can adjust virtually in real time so that you are getting a proper exposure and you never have to do the math to figure out what it is. You don't have to go into manual mode. You can still shoot in a semiautomatic mode when you're shooting with mechanical lenses on a mirrorless camera. It's really kind of a cool thing and then also because we get the the image on the sensor in real time all the time, we have something called focus peaking which allows us to see very, very critically what's in focus and we're going to look at both of these things real in real time. We're going to take a look through this camera here.

03:20          I've got to set up so I can adjust it and you can see what we're actually saying, but before we do that, let me. Let me take a close look at this lens. You see exactly the difference here. So here is a mechanical ends. You can see there are no contacts, right? If I grab a modern Lens on there, you've got the context on there that are going to communicate to the camera what the camera or what the Lens settings are, and this is not just what the aperture is, it's what the Lens model is. It's this one serial number. It's all kinds of extra information that is passed through. Whereas when you don't have those contacts, the camera effectively just thinks there is no lunch. It doesn't know the difference between there being no lens or one of these on here, and when I adjust the aperture on this, looking through it, you can actually see the apps are closing down, which is something you're not going to get on an electronic limbs.

04:02          That doesn't happen until you actually push the button to take the picture. Now, incidentally, if you were to take a lens like this, a standard electronic lens, put it onto a dslr camera. The one time that it does close down for you is when you hit that depth of field preview. That's when that does close down and then you see what the depth of field will look like, but at least last time I checked in, to be fair, it's been a while since I shot a mirrored cameras. You will see a much darker scene because it is actually restricting the amount of light. There's nothing. There's no way for the system to kind of gain that up to show you something brighter. Whereas on a mirrorless camera, since you don't, well first of all, you don't even have to stop it down when you're on a manual lens, but you can still do that with electronic lenses.

04:43          You can do the depth of field preview, it'll stop it down for you. So you see what's in focus, what that depth of field preview actually is. But the cool thing on mirrorless is it automatically gains it up, it brightens it up so that you still see the thing as a proper exposure. Kind of need, a little bit of a side note. There was kind of a cool side effect of that. So anyway, so on a lens like this, when we mechanically move the apps or close it down, it literally restricts the amount of light coming in and the sensor adjusts for that automatically. So that's what we're going to see here. So let's switch to looking through this system here at Mia actually popped this lens off here. Put this one on and just moment and let's switch over and see what we've got here.

05:20          Okay, so I am. I'm looking at another system here to the screen. I am wide open right now and I'm going to focus and using focus peaking. I will know when I'm in focus and you can see the folks speaking how cool this is. It especially on the beard. It really works out well. And if focus speaking by the way, the way that it works is it's looking for contrast. Really high contrast of areas of totally highest contrast possible is where it's going to put the red. In this case, red world changed the color and I'll show you how to do that, but you end up with this, uh, focus peaking. You can see these little lines and little red lines are blue lunch whenever you send it to you. So you see exactly what's in focus. And as I move, like right now, I'm just moving my body back and forth to move in and out of focus.

05:56          Or I can move the focus ring itself, of course. So as I said, I am wide open right now and you can see really nice, shallow depth of field in here, really nice Bokeh. But as I closed the lens down, as I start to close, I'm going to close it slowly and you're going to see the depth of field changing, but the exposure you might see a little bit of a wiggle in the exposure, but then it quickly compensates and corrects itself. So you see, look at it and how I'm almost all the way stopped down Aum, and the farther I get stopped down, the longer it takes the camera to adjust. But there you can see I'm stopped on all the way. The background is largely in focus. I've lost that beautiful Bokeh, and now I'm going to open it up very quickly and you're going to see the exposure go bad, right momentarily.

06:37          But then the camera quickly adjust for to buy. Slam it down the other way, close it, it goes to dark, and then he goes, oops. And it compensates for that. So the cool thing is if you're shooting video, you can actually adjust the exposure. It just the after wall. You're while you're shooting, if you want to get generally, it's not something you do, but you certainly can. So the one of the things that you do have to be aware of is that you have something called the right study here. The constant preview on if I turn constant preview off, then we're no longer getting to see the changes in here. So before I disabled that, let me do this. I'm going to show you that I am in manual iso. If you look at the ISO and the bottom right corner, you see it set to 400 right now.

07:14          Um, I want that manual. I don't want to set this to automatic, so I'm going to leave that manual and obviously we have no reading. So let's see if I can point to where it would be right about there. You see the zero point zero, that would be the after reading, but the camera doesn't know what the picture is. So it's just shows zero. And then to the right of that we are seeing. And unfortunately it's one of those things I just wished that that number was always there. Um, you see the shutter speed, it only shows up when I half press the shutter, even though it is constantly reading it. So I'm going to leave that. I'm going to keep pressing that. If it disappears, we'll tap, tap the shutter so it brings it back up again. But I'm wide open right now. I'm at an unknown aperture.

07:52          I bet an ISO of 400. That's right there. There's the ISO 400. And as I start to close it down, you can see the shutter speed, bring it back up. You see the shutter speed changing to compensate as I close the aperture down. So I need obviously a longer and longer shutter speed. Open it back up again. And there we go. So now for that to actually work properly, for you to actually see that exposure staying accurate, you do have to have the uh, the exposure preview turned on. And one of the cool things about this too, one more thing before I turned that off is if I do a manual exposure compensation, now you see right in the middle of the screen, I can go plus or minus on the exposure compensation. I can set the image to be brighter or darker, just depending on tasting or whatever I actually want.

08:33          Or if you know the camera's meter enough for some other part of it, I don't want to kind of compensate for that, but I'm not going to see any of that if this constant preview is not turned on. So if I turn this off right now, now the camera is going to show me what it, what it thinks is accurate. And it doesn't matter even if I go to manual modes. Let me go to full manual exposure on here. There we go. We're in full manual right now. Now look, it says to thousands of a second. That's where I left last left. It still looks like a proper exposure. Clearly that is not a proper exposure right now. And if I was to go in and turn constant preview back on, we're going to see it look very, very dark. The problem. There we go.

09:06          So that's what it would look like with that, with that setting, I need to manually. Oops, there we go. Manually. Just the exposure is just the shutter speed to make it proper. And so the whole point there that, that constant preview, the idea behind having that on is the camera is showing you what the exposure will actually look like. And you might be wondering why would you ever turn it off? The main reason you would want that office if you're shooting in a studio environment, imagine if you will, that I'm shooting in here in the studio with studio strobes and I'm going to set my camera to one 25th of a second f whatever, uh, ISO, whatever that one, 25th of a second is that is assuming that the strobe is firing when the strobe is not firing, then the image that the camera would capture to be really, really dark.

09:48          If constant previous turned on, I would see a really dark image. So by turning it off, then you see a correct exposure no matter what the camera is set to it, which is, that's when you need it. Okay, so that's that part of it. Now let's take a look at the actual focus peaking settings. They were going to go in here and we see that that is on or off, and if I turn it off then obviously we're going to lose the focus peaking. So when you're doing manual use, something you'd probably want on. But we also have these settings in here. Let's drop down to this and you have to detect levels low and high. If I set it too high, then it is a much more critical focus required. You see the color changes, but not as much. So look at my beard.

10:23          There's not anywhere near as much red as there was before. If we go to low, we're going to see a lot more of that. So basically the difference there is how critical the focus has to be. It's looking for a less critical focus when you're on low, which is fine if you're shooting it. And I'm gonna say a four or something like that point. If you're gonna shoot wide open on a lens like this one on here which have zero point nine five, that focus is really critical. And even though like at this point, if you look at my eye that's closer to the scene, so that's probably, yeah, that's going to be totally sharp. But as I move forward just a little bit, we still have some of the red sparkles on my eye, but that is probably not as focused as it. So there's definitely a difference in there were having that set to that high point is probably a good idea.

11:04          Um, and then you can change the color. So let's go to color here and in for whatever, you know, if you're shooting something that's got a lot of red in it than the, the seeing the red focus, baby's not going to be easy to see. So you can change that color on there. So. So that's basically how that works. So you have this difference where you've got the focus peaking, allowing you to measure that critical focus based off of contrast in the scene. And if you're thinking, wait, isn't that Kinda like contrast detection, autofocus? Yes, it's exactly what it is. It is the camera looking for those areas have the highest contrast and in this case highlighting them and then the exposure itself is adjusted automatically because the sensor is seeing the light coming through the scene in real time all the time. So that's pretty much all there is to.

11:41          It was kind of fun. Kind of cool. So if you have any questions about this, we're gonna jump into the q and a next. Uh, before I do that, I want to remind you guys that we do have one of the best ways to support this show is to go to photo Joseph Dot com slash member. And if you become a member there, you access to all kinds of cool stuff, including a private facebook group that is just for members only where we can, you know, I'm much more likely to be able to respond to questions on there if someone had asked a question about the gh five the other day when I was able to help them right away through that. And it's a place where I will be going live occasionally kind of randomly while I'm, I don't know, in the back of an uber or something like that. And I can just kind of go live and talk about whatever you guys want to talk about. This is one of the new benefits to membership there. So I encourage you to please go check that out. For now though, it is time for the live q and a. So if you're watching live, make sure you get your questions in there, put that footage estimate in front of them. And if you're not watching live, just drop your question in anytime into the comments. And I will do my best to get to see in a minute.