badlydrawnboy wrote:
I should have been clear that I'm posting 100% crops. These aren't really extreme close-ups.
A shutter speed of 1/160 at 70mm should be enough to stop motion blur, should it not? I was under the impression that 1 / 2x focal length with a FF camera would be sufficient. And the first picture at 50mm is 1/640.
I have calibrated the 24-70 with FoCal, and it returned a zero adjustment at 24mm and a -1 at 70mm.
I agree that a tripod and static subject would be a more controlled test. But I'm also interested in seeing how a lens performs in my normal shooting conditions. My 50/1.4 is very sharp above f/1.8 in normal shooting using the same technique and settings I used for these pictures. The same is true for my 40/2.8. The lenses I've had issues with are the Sigma 35/1.4 (obviously front-focusing by a significant amount), Sigma 85/1.4 (erratic focus) and possibly the 24-70 II (*maybe* slightly soft wide open, especially at 70mm).
Today I will try a more controlled test and see what I can learn.
And yes, perhaps I should send the 5D3 into Canon — with the 24-70. ...Show more →
first, just try some fast shutter high-contrast, low to moderate ISO, 10x zoom liveview manually focused shots and look at the best ones, if those look bad then you know the optics are bad
if those are good, then you may be getting shake (even on a tripod, if you don't use liveview mode you can get mirror slap shake which can make a mess, or if you don't let it settle down since many tripod, even sturdy still have a bit of bounce after you touch the camera) or poor AF (either due to the body or lens or simply poor MFA)
badlydrawnboy wrote:
A shutter speed of 1/160 at 70mm should be enough to stop motion blur, should it not?
depends, it usually is, but it is still possible to get shake there with these high density sensors used these days
and maybe the subject moved a tiny bit
of course it might be something less than ideal with the equipment
corndog wrote:
One problem with focusing on the front of something is that if the focus is even further in front, you wouldn't know. This is why I suggested grass, because there will always be something in the foreground and the background. Nature's test chart.
Apparently you are not familiar with the Lensalign system used for this . Do you see the ruler on the right hand side? It is at an angle to the focusing target on the left. It shows exactly what you meant and it gives you an arbitrary scale and it takes the guess work out. Just FYI, of course.
corndog wrote:
The guy spent over five grand on a camera and lens, nothing wrong with a little paranoia!
Yes, and I've had a pretty unlucky experience with the last few lens purchases:
– Canon 50/1.4: AF problems; sent to Canon and they confirmed lens assembly needed replacement.
– Sigma 85/1.4: AF problems; sent image sample to Sigma who confirmed problem, asked me to return to B&H
– Sigma 35/1.4: severe front-focus problem; sending back to B&H
I have a Canon 50/1.4 and 40/2.8 that have not issues at all.
The 24-70 appears to be fine, but I'll admit I was a little paranoid based on my previous experience.
Lars Johnsson wrote:
I think Canon should check your camera. I have seen 10-15 posts from you similar to this one with other lenses also.
And I don't think your way of testing lenses (both this or your Sigma 35) for sharpness is good at all. Every test shot that I have seen is an extreme close up of a small child and often wide open like here! How do you know the child didn't move two cm when you where shooting? Take test shots at a more normal distance and with a still subject. Maybe use a tripod also. Because you will move a little bit when shooting.
I would do it in another way than you. But if every lens you test isn't sharp enough for you. Maybe you need Canon to adjust your 5D3...Show more →
+1 ;-)
OP's last photo is focused on portions of the hat that appear to be farther away than the eyes, and there the focus is excellent for a handheld 100% crop.
To the OP,
If you are trying to test a Lens, you need to take AF (Phase Detect) variable and any motion and noise variables out of the equation. Using Live View will give you best focus, ensure enough light for low Iso and fast shutter. Now you will get sharpest potential image from your camera and Lens. I thing your pock holed wooden squirrel doesn't show squat, I can't tell where in each image is the sharpest or the point of focus. Based on what I see in this threat, imho you have not yet determined that your lens is ok, I would think it would be sharper for a MK II but you have yet to shoot an image ith clear delineation showing the focal plane (area of image more sharp than immediate part of image in fron and behind the plane) with all the AF, shitter,iso etc.
gschlact wrote:
To the OP,
If you are trying to test a Lens, you need to take AF (Phase Detect) variable and any motion and noise variables out of the equation. Using Live View will give you best focus, ensure enough light for low Iso and fast shutter. Now you will get sharpest potential image from your camera and Lens. I thing your pock holed wooden squirrel doesn't show squat, I can't tell where in each image is the sharpest or the point of focus. Based on what I see in this threat, imho you have not yet determined that your lens is ok, I would think it would be sharper for a MK II but you have yet to shoot an image ith clear delineation showing the focal plane (area of image more sharp than immediate part of image in fron and behind the plane) with all the AF, shitter,iso etc.
Does the LensAlign focus target not meet these criteria? It has a diagonal ruler designed to show front or back focus as well as a target with high contrast to focus on. I'm not sure what a better target would be than that?
. Do you see the ruler on the right hand side? It is at an angle to the focusing target on the left. It shows exactly what you meant and it gives you an arbitrary scale and it takes the guess work out. Just FYI, of course.
