Critical sharpness with Mamiya 7's 80mm lens

[jon_warwick2]

<p>Using a 10x Schneider loupe, I've noticed that images from my Mamiya 7 + 80mm lens are detailed and in focus with no "obvious" shake at all. And up to a size of 24"x20", I always get very crisp and apparently sharp prints.<br>

But I've also noticed that whilst they're all "good", it's only a MINORITY of slides that are blazingly sharp (ie, where I don't think they could be any sharper) when scrutinised under the 10x loupe. This minority of mega-sharp slides stand out as being something different from the pack. I'm currently using the Mamiya 7 handheld at normally 1/250 second. I'm also pretty confident that I've got a steady hand, and the leaf shutter is essentially without vibration. <br>

To be honest, all considered, I'm surprised that the vast majority of images aren't 100% perfectly sharp.<br>

My question is whether I'm not "treating" the Mamiya 7's 80mm lens quite right? <br>

It's generally assumed that you need faster shutter speeds or better technique (ie, tripod) for a Telephoto over a Wide Angle lens. <br>

So, should I be viewing the 80mm lens in MF as "wide angle" (given that's the angle of view it forms on 6x7 film), or more as a "telephoto" (that requires more care)? Perhaps ironically, I'd be the first to bolt my 35mm Leica film camera to a tripod when using a short telephoto lens!<br>

The question is all the more pertinent, because I'm looking to do a project that will require an output of very large (50x40") prints.<br>

Thanks for your views!</p>

<p> </p>

[bwbob]

<p>Check your rangefinder alignment. Not an uncommon problem with the Mamiya 7. If the image is diffusely unsharp it is more likely a motion phenomenon. For really critical image sharpness always use a tripod no matter how steady your hand is. Mamiya 7 lenses are among the sharpest in medium format and I have never had an issue with the 80mm but then I never hand hold. Good luck</p>

[johncox]

<blockquote>

<p>should I be viewing the 80mm lens in MF as "wide angle" (given that's the angle of view it forms on 6x7 film), or more as a "telephoto" (that requires more care)?</p>

</blockquote>

<p>It's a standard angle lens approximately 40mm in 35mm world.</p>

<blockquote>

<p>But I've also noticed that whilst they're all "good", it's only a MINORITY of slides that are blazingly sharp (ie, where I don't think they could be any sharper) when scrutinised under the 10x loupe</p>

</blockquote>

<p>This could be due to aperture, all lenses perform better at certain apertures. That's my guess.</p>

[david_henderson]

<p>You'd need to guess the answer to this but how much is due to depth of field issues? It may be that the very sharp pictures are where the main subject is all on a plane with the point of focus? You can't see dof through the lens with a rangefinder and dof is less than some people will be used to. There will be plenty of pictures where you can't get everything sharp across the frame and where you have to choose where you want your point of focus/maximum sharpness to be and accept the consequences. <br>

You will also find those ho will say that there is a visible difference in sharpness between a good tripod -assisted shot and handholding at pretty much any shutter speed. </p>

 

[donbright]

<p>In handholding camera's where you have success intermittently is not unusual. We just can't know what kind of motion we have induced at the moment of exposure. We can guess, but generally we're busy in getting the shot right, and not totally aware of that decisive moment as to the kind of shake we caused. The tripod, of course takes away the shake equation, then there is the issue of aperture diffusion. It can also be the quality of light in that frame that may, or may not agree with the type of lens coating on that lens. Light quality does affect our perception of sharpness. Bad light will distort the appearance of the objects emphasized in the scene. In medium format work, those that boast their success in handholding the camera, usually show their successes, but won't reveal the failures. Right to the move from 35mm to medium format, I just presumed the tripod would be my friend.</p>

[gerard_bynre]

<p>It could be motion blur - you will never know until you properly test with a tripod, and / or flash exposure. But as Robert says, the Mamiya 7 seems to be highly prone to rangefinder misalignment. I've noticed these issues with mine - where somehow the sharp part of the image always appeared to be just in front of what I thought should be sharp. Again, you can test on a tripod, lens wide open, with a clear and definitive focus point / scale.<br>

As I'm sure you are aware, the 80mm lens is really sharp and should give great results, but the camera body is less dependable. All things considered, I get more consistent results from my Canham DLC 5x4 then I do from the Mamiya, albeit the comparison is not on an even playing field. Then again I also bought the 150mm lens for the Mamiya 7, which sort of gives the rig a bad rep. Its much harder to use than even a LF camera with a long lens, whether on a tripod or not. So maybe I'm prejudiced, but I find the Mamiya 7 a wonderful, and wonderfully tricky camera to use.</p>

<p> </p>

[david_henderson]

<p>If you had a rangefinder adjustment problem I'd expect to see photographs that are consistently unsharp and always in the same direction (ie back focus or front focus). This isn't what you describe. I'd be looking at user-driven faults first, eg focussing accuracy, camera or subject movement, or as I said above, depth of field. For each of these there are improvements you can make before your project comes along. </p>

<p>I'd suggest though that independent of all else, if I wanted pin sharp 50" x 40" prints from a 67 camera, I'd be using a tripod and slow film rather than constantly worrying about keeping my shutter speed high. </p>

[andrew_gardiner]

<p>A tripod, preferably not using a centre column, and a cable release. Without starting at this basic point it's just all conjecture surely?</p>

[gerard_bynre]

<p>The camera has a justifiably big reputation, and users expect a lot from it. But casually used, which its handiness encourages, its very very unforgiving (esp. that 150mm lens). Therein lies the paradox of the Mamiya 7.</p>

[joshloeser]

<p>The 80/4 is a phenomenally sharp lens. It is as sharp wide open as most other lenses are stopped down, no matter what lens you're talking about. It doesn't really improve when stopped down, which is mainly because it's so sharp to begin with. All you're gaining is more depth of field at smaller apertures. <br>

I've gotten sharp images with the 80 at 1/30th at f/4, though of course that's uncommon (in large part because I don't shoot like that much).<br>

It takes time to learn how to use the 7. I picked up the basics from the first roll I shot and made good photographs from the beginning. Since then, I've learned it well enough to say that I've mastered it. It just takes time and experience.</p>

[jose_angel]

<p>Just spend a couple rolls checking focus and apertures at a given distance (with a good tripod&cable release), and your handholding technique at different speeds (shooting a led dot in a dim room).<br>

If you shoot b&w film, think that different developers could show dramatic differences.</p>