After the 450D presses the shutter halfway to focus, can I shift it and press the shutter again?

If you deflect too much from the new composition after focusing, it will cause blurring, especially if the aperture is too large. There are several solutions, one is to re-select the focus point or focus object, one is to use a smaller aperture to make the depth of field wider, and the other is that if the lens you use has full-time manual focus, that is, the lens is focused, and you can also rotate the focus ring for manual focus after pressing the shutter halfway, and you can also solve it with a little fine-tuning, but this method requires more skill, and there are two conditions for recomposing the photo after pressing the shutter halfway to focus: 1. You can't relax the shutter when recomposing, Otherwise, pressing the shutter again will refocus on a place other than the subject, and the subject will be blurred.

2. The focal length is already locked after pressing the shutter halfway, and the distance between the camera and the subject will change after reframing, and once this distance changes too much, the subject will naturally be blurry when it is out of focus.

So, one is not to relax the shutter, and the other is not to change the focal length too much when recomposing.

Of course, hand tremors can also cause blurring.

Normally, theoretically, it won't be out of focus, but it can be done!

But in fact, many lenses can do this when they are new, and they must not be out of focus! But if you use it for a long time, there will be out-of-focus phenomenon!

Therefore, it is recommended to develop the habit of composing the picture first and then setting the focus of the object! Shoot with a good focus!

This is my experience!

If you can't release the shutter halfway, you can also set other focus lock methods.

Zoom the composition first, then press the shutter halfway to focus, and then press the shutter all the way down to complete the shot.

Another way is to identify the subject first, press the shutter halfway to focus, move the camera to complete the composition, and then press the shutter to the end to complete the shot. Remember to keep the shutter pressed halfway during the composition process to avoid losing focus.

Pull the lens to the closest, focus, and then no matter how you push and pull, it won't be misaligned, and half-press the shutter to focus? Is that automatic? If so, then it's best to frame the shot first and then press the shutter to focus.

When you press the shutter halfway, if you turn on the autofocus, the camera will start autofocusing, and then you should keep the camera steady, and then press the shutter and slowly release it, so as not to shake the picture.

According to your description, you press the shutter halfway, the focus is done, and then you have to recompose the shot, and in this process, the camera is constantly adjusting through the reflection of the lens, and then the focus is not complete, and you press the shutter, so the focus is out of focus, and the focus is finished, and it is easy to shake when you press the shutter, which will cause the image to be blurry.

Hope it helps.

It's no problem, it's your problem. When the camera is shooting, it is according to the data measured by pressing the shutter half-before**, you have measured it, the focus is on, if you are moving, it is no problem to ensure that the distance of the focused object remains the same, but the distance changes and it will naturally go out of focus! Hope that helps.

The right way to focus:

If you want to place the person on the left side of the frame, move the camera to the right to reframe the shot (but never readjust the focal length) and press the shutter again.

Generally, it is not until the shutter is pressed halfway again that the camera will "refocus".

So, when you release the shutter, the "focus distance" will not change until the next time you press the shutter again.

Note: "Focus distance" is not the same thing as "focus". The focus distance does not change (the lens focus ring does not move), which does not mean that the focus point does not change.

For example, if the focusing distance is 5 meters, your focus can fall to A 5 meters away, or to B 5 meters away.

You're wrong in this way, so there's no need to fight;

First of all, you have to shoot a certain object, you press the shutter halfway to focus, and then you move the camera, and then even if you press the focus lock at this time, it is useless, because the focus is no longer on the object you want to shoot, the correct way is to press the shutter halfway to refocus, unless you want to shoot an out-of-focus **;

Yes because you release the shutter, it won't change if you don't let go and keep the shutter halfway.

Yes. Because of the cosine difference (please google it yourself).

It depends on whether you set the fixed focus point, if it is fixed, then no matter how you shift it, it will not change the focus point, only the focal length.

If it's not fixed, it may change, unless your object is still on this optimal focus point.

Metering and focusing are two different things, and it's fine if you reframe the shot after metering.

If your focus point is not focused, you can change the method of focus point to avoid being out of focus.

Also, if you don't focus at close range with a wide aperture and then recompose the shot, you don't have to think too much about out-of-focus.

Normally, the autofocus camera focuses on the set focus point when the shutter button is pressed halfway, and the focus locks when the focus indicator appears, and as long as the button is not released, the shutter can be reframed and the shutter can be pressed without falling out of focus. A better DSLR camera may also have other autofocus modes, so it's best to read the manual to understand the performance of the camera in your hand, so that you can do whatever you want when taking pictures.

In the case of a single focus, continuous focus and half pressing the shutter will not lock the focus, and will refocus according to the focus movement caused by the movement of the camera. But if it's set, after locking the focus and panning, it won't run out of focus, of course, strictly speaking, it will run, because you're not panning, but an arc, but it's very slight, as long as it's not a large aperture at every turn, you shouldn't be able to see it.

Under normal circumstances, SLRs have tracking and focusing functions, as well as lock focusing functions, after the focus is completed, press the lock button, and then re-compose the photo will not be out of focus, I don't know what brand of camera you are using, different camera settings are different, but the function is definitely there, you can refer to the camera's manual.

After focusing, keep pressing the shutter halfway, and it will no longer be out of focus.

Downfocus is a phenomenon that occurs on individual lenses on individual bodies, and has nothing to do with operation.

In single-shot focus mode, the shutter button will not be out of focus as long as you do not release the half-pressed shutter button.

Recompose the shot to see if you move back and forth or left and right, depending on the size of your aperture and the depth of view.

Reframe the shot, the focal length remains the same, and it will not be out of focus.

As long as it is a SLR, there is a probability of being out of focus, and it has nothing to do with the focusing method.

Is there not enough light? This happens when there is not enough light, and do you set multiple focus points? It is recommended to set only one focus point, focus on the subject, and press the shutter halfway to focus before composing the shot.

It is better to use manual focus for shooting long shots, and you can use the screen to zoom in to see if it is the clearest state. Although the camera has an auto-fit function, it is not always possible to close the focus where you want to focus.

It is recommended that you can choose the manual focus point, and after setting the focus point you want to choose, you can solve this problem by shooting in the composition. See the manual for specific operation!

Some experts have already given some advice, so let me remind you to add it.

It's also common for the autofocus function of many lenses to go out of focus. Fortunately, I haven't owned the sub-factory lenses for the time being, and for the time being, all the original lenses have not encountered this problem.

In addition, when focusing manually, please adjust the diopter of your viewfinder, otherwise the manual focus you see in the viewfinder is actually very likely to be biased back and forth.

All of the above is not considered as a small depth of field at the maximum aperture, and all of the above are discussed in the case of testing and focusing at the maximum aperture.

Maybe you're using a deep field effect with a wide aperture.

Hello; The camera lens out of focus should be the lens of the sub-factory, if the original lens please go to the maintenance to see, it should not be too big a thing. If you're going to use manual focus now, that should be the best choice. As for how much you move in the motivation position after focusing well, it's really hard to grasp. All right.

<>Don't you read the manual?

The problem you're talking about is focus locking. Keeping the shutter halfway locked to the focus point (i.e., locked distance), the distance between the subject and the camera basically doesn't change when you compose the shot again, so the subject is still sharp.

PS: Not every camera has a half-press shutter to lock focus, this depends on the settings and model. Some use the shutter button halfway to lock**, while others use the AF-ON button to lock the focus.

You mentioned this good focusing habit.

It depends on the specific shooting environment:

If you want to shoot news, sports, etc., and the object distance is relatively unstable, you generally need to cooperate with continuous focus (artificial intelligence automatic servo focus) to shoot.

To say that the more professional focusing habits are done by manual focusing with automatic focusing.

Didi focused successfully, and the focus was locked.

Theoretically, this moving composition is inaccurate, which is called the cosine error. Originally, your focus is on the face, but if you move the focus, the distance from the face to your camera becomes a right-angled edge. This error is more noticeable for larger apertures.

Many people think that the camera is out of focus, but in fact, this is the reason, and they do not have good focusing habits.

But it's really convenient to do so, and in many cases you don't have time to choose the focus point at all, so it depends on your aperture. I feel that the average aperture is above, and the impact of this error is actually negligible.

In order to get the most accurate focus, you must use the focus point closest to the focal point and try not to move the frame composition. For example, if you want to focus on the model's eyes, you must use the focus point closest to the eyes and shoot immediately after locking it. In general, posing will be more relaxed, so try to use this focusing method.

If it's a snap, then there's no way but to make do.

With a single focus, focus on the eyes first, then lock the composition, and then **. I've always done this in the studio.

If the camera is barely on a tripod, your body will move, and the model will move, so it is better to find a closer focus point to shoot directly, and the post-cropping effect will be good, and the chances will be blurred.

When you press the shutter halfway, the collection distance is locked, and then the frame is reframed, as long as you pan the camera and don't change the shooting distance, you still clearly shape me after 2025.

Pan the camera so that you don't move as much as possible, and it generally doesn't get out of focus.

Reframing will not be clear.

Portraits are taboo to recompose.

Because the photographer is moving, so are the models.

Reframing can easily cause out-of-focus, and the intention is to keep the eyes in focus, but both are moving, and it is difficult to ensure that the eyes are still in focus.

This approach is feasible if it can be ensured that it does not move.

A better way is to adjust the focus point so that the focus point is for the eyes or face, and then crop the composition later.

The 6D has a little less focus point, and the composition on the side is not convenient.

There is a cosine error, and if the aperture is too large or easy to degum, trade with the focus point closest to the eye.

It also depends on your metering mode.