What is your technique to focus M lenses?
Bear in mind that the beep and red square isn't the focus confirmation, at least with my K-r. The green hexagon is the focus confirmation. They are always pretty close, but it might be enough if you are relying on the beep.
Check the diopter for the viewfinder is properly adjusted. If it's clear in the viewfinder, but not in the picture, then that might be the problem.
You could double check using liveview. I often find myself using that, particularly for macro and find it pretty accurate.
Lastly, perhaps use a smaller aperture to give greater depth of field.
All the above is based on my experience with the K-r. It should be pretty general advice, but you might not have liveview, for example, depending on your camera model.
Here are some links I found useful.
link
link
link
Hope these help,
Nigel
I don't have the lens you do but as mentioned above it is best to wait for the green hexagon as that is focus confirmation.
With my m42 preset lens I open the apeture to aid focus then stop down to take the picture.
With my m42 'auto' lens I switch to a which leaves the apeture wide open - focus and the switch to manual and take the shot - same thing - slightly different technique
My other mf lenses are later models (pk/m I think but without checking I could be wrong) and they hold the apeture wide open until the shot is taken so it is as simple as focus, presss the green button for the exposure and shoot
Patience and practice are key though - stick with it and I am sure you will be fine
For wildlife I try to prempt where they may be then pre focus and wait for the shot
Hope this helps
Stu
Thanks and welcome more good advice.
Another technique that is almost foolproof is to use the Live View feature on the LCD screen and zoom in on the area that requires critical focus (zoom is achieved by repeatedly pressing the 'Info' button). However, this is only possible if you're using a tripod and the subject is perfectly still. Great for indoor still life shots.
Regards
David
Focus Confirmation = you can see this in your VF - it is the little green hexagon. When lit it shows you that the subject is in focus. Note however that there is a 'range' (also with AF) so it depends on whether you are focusing from Infinity DOWN to your subject or from minimum focus distance UP to your subject. For each lens one direction will always give sharper shots (and it does vary from lens to lens though for most of mine it is Infinity DOWN to the subject). This is easy to check on the K7/K5 by taking one shot from each direction and then using the side-by-side review mode and zooming in to see which is sharper, do this a few times and you will now be certain which it is.
Take a look at this link too : link
Nikon. D800. D600. Sigma 500/4.5, Nikon 300/2.8 VRII, Sigma 120-300/2.8, Zeiss Distagon ZF2 21/2.8, Zeiss Distagon ZF2 35/2.0, Sigma 50/1.4, Nikkor 85/1.8, Nikon TC20EIII, Nikon TC14EII, Kenko x1.4, Sigma 2.0
Just to emphasise what Trickletreat said above as this was the biggest issue I found when I started using MF lenses :
Focus Confirmation = you can see this in your VF - it is the little green hexagon. When lit it shows you that the subject is in focus. Note however that there is a 'range' (also with AF) so it depends on whether you are focusing from Infinity DOWN to your subject or from minimum focus distance UP to your subject. For each lens one direction will always give sharper shots (and it does vary from lens to lens though for most of mine it is Infinity DOWN to the subject). This is easy to check on the K7/K5 by taking one shot from each direction and then using the side-by-side review mode and zooming in to see which is sharper, do this a few times and you will now be certain which it is.
Take a look at this link too : link
I didn't know that. Very helpful, thanks.
What's interesting is that what was once perfectly normal technique, using our eyes, seems to have become an issue where we look to the camera to tell us instead.
I wonder whether it's still not quite understood how to adjust the viewfinder. Point the camera at a blank wall or blank area, adjust the dioptre lever until the etched lines in the viewfinder are crisp.
Do not adjust the dioptre by viewing any sort of scene or subject as the eye adapts and the adjustment will not be correct.
2. The green hexagon light has a margin of error. Turn your focus ring slowly, and you will notice the green light come on, but it will stay on while the ring is turned until it goes off again. The optimum focus will be between the point where the light comes on and the point goes off. You can learn to anticipate where this point will be.
3. Manual focussing by eye - again, as you move the focus ring you'll notice the point where the image comes into focus and the point where it goes out of focus again; try and sense the optimal point in the middle where the correct focus will be.
4. Live-view focussing is with an enlarged view is the most accurate technique, and if you are shooting a subject many feet away, it doesn't matter if the camera moves an inch or two because you are hand holding it.
It seems to depend very much on our eyesight. I know for example that my dad had dreadful problems focusing his Nikons, despite being a precision, close worker. Maybe he had just worn out his eyes with so many years of close concentration, who knows. He tried everything, struggling with focusing magnifiers to even focus landscape shots.
Sometimes lateral thinking is needed and if anyone has severe manual focusing problems and for whatever reason can't use autofocus, then just maybe a rangefinder system would be easier and more accurate for them.
The traditional advice is that rangefinders are more accurate up to about 135mm and beyond that SLRs are more accurate.
Hopefully Pentax will one day release an EVF model which will combine the features of live view with a shielded, eye level viewfinder. Until then, stopping down to ensure decent DOF when using the OVF, plus resorting to help from the live view monitor for shallow dof focussing, are workable.
In the context of the M series lenses a better solution perhaps.
The other possibility is the Q with the new K mount adapter, when that becomes available. Third party adapters are already freely available on Ebay, for all sorts of lens mounts, but I think I'll wait for the Pentax one.
Just practice. You don't even have to pop off a shot. Just wander around with the camera switched off finding best focus on objects and people. Rock through best focus back and forth and learn to recognise when you've hit the spot.
The slightly weird thing for me is that the direction of operation of the lens barrel on Pentax is opposite to the general convention. So infinity and MOD are reversed which still catches me out. I'll see that I need to focus forward or back but because of years turning the barrel clockwise for forward and anti-clockwise for back toward infinity I still sometimes forget myself with the pentax and go the wrong way first rather than just directly to best focus.
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258 posts
14 years
Glasgow
PS - I did check BF/FF and it is as good as it can be.
Thanks