Meyer-Optik 58/1.9 M42 Lens on 5D

<p>Just a quick question. I have an old Meyer-Optik 58 f/1.9, M42 screwmount lens that I was just testing on my 5D, since I wanted to see what kind of effects I could get with its 14-blade diaphragm. Anyways, I noticed that even tho the shot was focused and looked sharp in the viewfinder, the RAW files didn't really look that sharp until the lens was stopped down to f/8 or f/11.</p>

<p>Slightly curious, I then took three more shots at f/4 - one where the lens was focused so the shot looked good in the eyepiece and then two more, with the lens focused slightly in front of and slightly behind the main object in the shot. And you know what? The shot with the lens focused slightly behind came out very sharp.</p>

<p>So, I'm wondering if this is just an issue with the lens - perhaps it needs to be serviced so the focus is accurate? Or, is this just a side effect of mounting an M42 lens on a Canon 5D?</p>

<p>If your eyepiece diopter correctly adjusted? With the standard screen it is often difficult to manually focus. I suppose it is possible your screen might have been knocked out of true. </p>

<p>My eyepiece diopter is correctly adjusted. I do agree that it is hard to manually focus with a standard screen. I've been spoiled by the film SLR cameras that have the split prism rangefinder focusing screen - whatever it's called. While the screen could've been knocked out, my camera 5D was just serviced in November.</p>

<p>As I remember frommy Exakta times, Primoplan is a rather average lens but it should be sufficiently sharp at f/4 or so. Perhaps it needs adjustments/collimation, or the adapter doesn't allow full infinity focus?<br>

Also, you may want to try it on a camera with Live View (@ 10x LCD magnification for precise focusing.)</p>

<p>Although I've never personally had any of them out of spec, have you checked the <em>adapter</em> used with another M42 lens?</p>

<p>In addition to the above....many DSLR viewfinders, unlike film SLR cameras, are not optimized for shooting with a f1.9 aperture, but rather more like f2.8 or so. I've personally found achieving perfect focus at wide apertures (f1.8 or wider) on my DLSR a bit more challenging than with my film bodies.</p>

<p>If the focus screen and the sensor disagree about where perfect focus is, the reason is probably the focus screen being misaligned.</p>

<p>Have you changed the focus screen? Perhaps it isn't seated properly.</p>

<p>If you have a 5D mk II or mk III, it's easiest to get focus right in Live View. The 5D mk I does not have that option.</p>

<p>....If you're focusing at f/1.9 then stopping down before taking the picture, another possible cause is focus shift. This can be fairly pronounced with some wide-aperture lenses. You can work around this by focusing while stopped down to the aperture you intend to use.</p>

<p>What you might be seeing is uncertainty of focus due to spherical aberration. A lens with spherical aberration has best focus for marginal rays which is different from the best focus for axial rays, which is different again from the "average" best focus. It can also show focus shift on stopping down so you need to focus at the shooting aperture, not wide open.</p>

<p>Your focus screen could also be out of registration (despite being serviced).</p>

<p>The focus screen could be out of service. Let me also better explain what I was doing. I just wanted to shoot some images using the lens and my 5D body to see how the lens performed at various apertures. I normally wouldn't otherwise use this lens wide open at 1.9.</p>

<p>With my first run through, I focused so the image looked sharp in the viewfinder, but the RAW files didn't show sharpness until f/8 or f/11. After I adjusted the focus - and I don't remember if I focused more in front of or a bit behind the main object - once I hit f/4, things sharpened up nicely. Everything taken at 1.9, 2 and 2.8 looked better too, but it was clear that the lens didn't hit its sweet spot until f/4, and I figured it wouldn't hit its sweet spot until then either. FYI, I did zoom into 100% magnification to check sharpness. Looking at the whole image fit on the screen at once, it does seem to sharpen up well at 2.8, but zoomed in at 100%, f/4 was the winner.</p>

<p>I have used other M42 lenses on this camera, all of the Pentax Super Takumar variety and I don't believe there were these issues, tho I will have to go back and check now. I have a standard adapter that allows for infinity focus. My 24-105 that I normally use with the 5D always shoots as the focus screen shows.</p>

<p>I also have an adapter to use Nikon lenses on my 5D, which has focus confirmation and to the best of my knowledge, so long as the lens is in its sweet spot, no worries.</p>

<p>While this is an issue unrelated to Canon, I have a Nikon 50/1.4 lens that was converted to be used as an AI lens. However, also when I shoot with this lens on a Nikon SLR body, the few times I've tried to use the lens at 1/1.4 - while the split-image focus screen in my FE2 shows sharp focus, when the film is developed and negatives scanned, the focus usually ends up being a bit in front or a bit behind of the spot I wanted. However, that issue is much less of a problem on my D800, between focus confirmation and live view. I know this isn't Canon related, but I just wanted to mention it.</p>

<p>The focus screen could be out of service. Let me also better explain what I was doing. I just wanted to shoot some images using the lens and my 5D body to see how the lens performed at various apertures. I normally wouldn't otherwise use this lens wide open at 1.9.</p>

<p>With my first run through, I focused so the image looked sharp in the viewfinder, but the RAW files didn't show sharpness until f/8 or f/11. After I adjusted the focus - and I don't remember if I focused more in front of or a bit behind the main object - once I hit f/4, things sharpened up nicely. Everything taken at 1.9, 2 and 2.8 looked better too, but it was clear that the lens didn't hit its sweet spot until f/4, and I figured it wouldn't hit its sweet spot until then either. FYI, I did zoom into 100% magnification to check sharpness. Looking at the whole image fit on the screen at once, it does seem to sharpen up well at 2.8, but zoomed in at 100%, f/4 was the winner.</p>

<p>I have used other M42 lenses on this camera, all of the Pentax Super Takumar variety and I don't believe there were these issues, tho I will have to go back and check now. I have a standard adapter that allows for infinity focus. My 24-105 that I normally use with the 5D always shoots as the focus screen shows.</p>

<p>I also have an adapter to use Nikon lenses on my 5D, which has focus confirmation and to the best of my knowledge, so long as the lens is in its sweet spot, no worries.</p>

<p>While this is an issue unrelated to Canon, I have a Nikon 50/1.4 lens that was converted to be used as an AI lens. However, also when I shoot with this lens on a Nikon SLR body, the few times I've tried to use the lens at 1/1.4 - while the split-image focus screen in my FE2 shows sharp focus, when the film is developed and negatives scanned, the focus usually ends up being a bit in front or a bit behind of the spot I wanted. However, that issue is much less of a problem on my D800, between focus confirmation and live view. I know this isn't Canon related, but I just wanted to mention it.</p>

<p>The focus screen could be out of service. Let me also better explain what I was doing. I just wanted to shoot some images using the lens and my 5D body to see how the lens performed at various apertures. I normally wouldn't otherwise use this lens wide open at 1.9.</p>

<p>With my first run through, I focused so the image looked sharp in the viewfinder, but the RAW files didn't show sharpness until f/8 or f/11. After I adjusted the focus - and I don't remember if I focused more in front of or a bit behind the main object - once I hit f/4, things sharpened up nicely. Everything taken at 1.9, 2 and 2.8 looked better too, but it was clear that the lens didn't hit its sweet spot until f/4, and I figured it wouldn't hit its sweet spot until then either. FYI, I did zoom into 100% magnification to check sharpness. Looking at the whole image fit on the screen at once, it does seem to sharpen up well at 2.8, but zoomed in at 100%, f/4 was the winner.</p>

<p>I have used other M42 lenses on this camera, all of the Pentax Super Takumar variety and I don't believe there were these issues, tho I will have to go back and check now. I have a standard adapter that allows for infinity focus. My 24-105 that I normally use with the 5D always shoots as the focus screen shows.</p>

<p>I also have an adapter to use Nikon lenses on my 5D, which has focus confirmation and to the best of my knowledge, so long as the lens is in its sweet spot, no worries.</p>

<p>While this is an issue unrelated to Canon, I have a Nikon 50/1.4 lens that was converted to be used as an AI lens. However, also when I shoot with this lens on a Nikon SLR body, the few times I've tried to use the lens at 1/1.4 - while the split-image focus screen in my FE2 shows sharp focus, when the film is developed and negatives scanned, the focus usually ends up being a bit in front or a bit behind of the spot I wanted. However, that issue is much less of a problem on my D800, between focus confirmation and live view. I know this isn't Canon related, but I just wanted to mention it.</p>

<p>The focus screen could be out of service. Let me also better explain what I was doing. I just wanted to shoot some images using the lens and my 5D body to see how the lens performed at various apertures. I normally wouldn't otherwise use this lens wide open at 1.9.</p>

<p>With my first run through, I focused so the image looked sharp in the viewfinder, but the RAW files didn't show sharpness until f/8 or f/11. After I adjusted the focus - and I don't remember if I focused more in front of or a bit behind the main object - once I hit f/4, things sharpened up nicely. Everything taken at 1.9, 2 and 2.8 looked better too, but it was clear that the lens didn't hit its sweet spot until f/4, and I figured it wouldn't hit its sweet spot until then either. FYI, I did zoom into 100% magnification to check sharpness. Looking at the whole image fit on the screen at once, it does seem to sharpen up well at 2.8, but zoomed in at 100%, f/4 was the winner.</p>

<p>I have used other M42 lenses on this camera, all of the Pentax Super Takumar variety and I don't believe there were these issues, tho I will have to go back and check now. I have a standard adapter that allows for infinity focus. My 24-105 that I normally use with the 5D always shoots as the focus screen shows.</p>

<p>I also have an adapter to use Nikon lenses on my 5D, which has focus confirmation and to the best of my knowledge, so long as the lens is in its sweet spot, no worries.</p>

<p>While this is an issue unrelated to Canon, I have a Nikon 50/1.4 lens that was converted to be used as an AI lens. However, also when I shoot with this lens on a Nikon SLR body, the few times I've tried to use the lens at 1/1.4 - while the split-image focus screen in my FE2 shows sharp focus, when the film is developed and negatives scanned, the focus usually ends up being a bit in front or a bit behind of the spot I wanted. However, that issue is much less of a problem on my D800, between focus confirmation and live view. I know this isn't Canon related, but I just wanted to mention it.</p>

<p>The focus screen could be out of service. Let me also better explain what I was doing. I just wanted to shoot some images using the lens and my 5D body to see how the lens performed at various apertures. I normally wouldn't otherwise use this lens wide open at 1.9.</p>

<p>With my first run through, I focused so the image looked sharp in the viewfinder, but the RAW files didn't show sharpness until f/8 or f/11. After I adjusted the focus - and I don't remember if I focused more in front of or a bit behind the main object - once I hit f/4, things sharpened up nicely. Everything taken at 1.9, 2 and 2.8 looked better too, but it was clear that the lens didn't hit its sweet spot until f/4, and I figured it wouldn't hit its sweet spot until then either. FYI, I did zoom into 100% magnification to check sharpness. Looking at the whole image fit on the screen at once, it does seem to sharpen up well at 2.8, but zoomed in at 100%, f/4 was the winner.</p>

<p>I have used other M42 lenses on this camera, all of the Pentax Super Takumar variety and I don't believe there were these issues, tho I will have to go back and check now. I have a standard adapter that allows for infinity focus. My 24-105 that I normally use with the 5D always shoots as the focus screen shows.</p>

<p>I also have an adapter to use Nikon lenses on my 5D, which has focus confirmation and to the best of my knowledge, so long as the lens is in its sweet spot, no worries.</p>

<p>While this is an issue unrelated to Canon, I have a Nikon 50/1.4 lens that was converted to be used as an AI lens. However, also when I shoot with this lens on a Nikon SLR body, the few times I've tried to use the lens at 1/1.4 - while the split-image focus screen in my FE2 shows sharp focus, when the film is developed and negatives scanned, the focus usually ends up being a bit in front or a bit behind of the spot I wanted. However, that issue is much less of a problem on my D800, between focus confirmation and live view. I know this isn't Canon related, but I just wanted to mention it.</p>

<p>The focus screen could be out of service. Let me also better explain what I was doing. I just wanted to shoot some images using the lens and my 5D body to see how the lens performed at various apertures. I normally wouldn't otherwise use this lens wide open at 1.9.</p>

<p>With my first run through, I focused so the image looked sharp in the viewfinder, but the RAW files didn't show sharpness until f/8 or f/11. After I adjusted the focus - and I don't remember if I focused more in front of or a bit behind the main object - once I hit f/4, things sharpened up nicely. Everything taken at 1.9, 2 and 2.8 looked better too, but it was clear that the lens didn't hit its sweet spot until f/4, and I figured it wouldn't hit its sweet spot until then either. FYI, I did zoom into 100% magnification to check sharpness. Looking at the whole image fit on the screen at once, it does seem to sharpen up well at 2.8, but zoomed in at 100%, f/4 was the winner.</p>

<p>I have used other M42 lenses on this camera, all of the Pentax Super Takumar variety and I don't believe there were these issues, tho I will have to go back and check now. I have a standard adapter that allows for infinity focus. My 24-105 that I normally use with the 5D always shoots as the focus screen shows.</p>

<p>I also have an adapter to use Nikon lenses on my 5D, which has focus confirmation and to the best of my knowledge, so long as the lens is in its sweet spot, no worries.</p>

<p>While this is an issue unrelated to Canon, I have a Nikon 50/1.4 lens that was converted to be used as an AI lens. However, also when I shoot with this lens on a Nikon SLR body, the few times I've tried to use the lens at 1/1.4 - while the split-image focus screen in my FE2 shows sharp focus, when the film is developed and negatives scanned, the focus usually ends up being a bit in front or a bit behind of the spot I wanted. However, that issue is much less of a problem on my D800, between focus confirmation and live view. I know this isn't Canon related, but I just wanted to mention it.</p>

<p>Ok, ok, ok, ok, ok, ok...</p>