AF misses. Canon

ThrillaMozilla wrote:

Read the manual.

DUH! That is not nice.

I believe you have to wait for the solid green light to be sure it's focused.

The green circle always lights up at the same time as the red view finder LEDs light up. So, a rude post without any reason or sense.

ohrid wrote:

Hi! I have an old 450d Canon. I noticed my wide-angle lenses such as 24mm and 10-18mm are often misses the focus despite AF blinks as focused on viewfinder. I wonder is it camera's problem or what? Thanks

Do they miss focus in standard static scenes? How do they miss focus, are they focussing on something close to the AF point you have selected, or is it a total focus miss? You don't have all AF points active, right?

Can you post an example or two, explaining where you AF point was, so it shows the miss-focus to us?

It misses like without any reason in standard static scenes. It looks more like FF/BF but I tested lenses and they doing well. What do you mean "all AF points active"? I use automatic selection or single AF point from time to time.

Here are a few examples

https://photos.app.goo.gl/uurDU1YDmegbbMVJ3

No. All out of focus. It looks like bf/ff, but on tests all the lenses are within norm. And the misses happen like 1 out of 5 shots

ohrid wrote:

No. All out of focus. It looks like bf/ff, but on tests all the lenses are within norm. And the misses happen like 1 out of 5 shots

How are you letting it focus? You choose the autofocus point or let the camera choose which to use?

if you choose the autofocus point, which one?

ohrid wrote:

Hi! I have an old 450d Canon. I noticed my wide-angle lenses such as 24mm and 10-18mm are often misses the focus despite AF blinks as focused on viewfinder. I wonder is it camera's problem or what? Thanks

Wow - heck of a start to dpr.

Since your question is so general the answer needs to match it ( you need details to get a detailed answer ie something more than a why are my fotos $@#(* ) . The answer is " or what " .

Lets start with some basics - what's your equip :

eos 450d with which version of which lens

> non usm

> is

> stm

> " L " , ef , or efs for 24 and 10-18 is efs - yes ?    or did you use others ?       " such as "  ?

> or what ? 3rd party ?

imho - The lens ( or PPing ) is the limit to what I saw when you finally posted exemples - at least my 450(s) are taking much sharper pics with a decent lens - the is or stm from canon . Do you have an " or what " lens ? What is it ?

Your choice of 5.6 or 6.8 is of interest . The 450 can take really sharp pics at 9.0 to just about 12.0 without any ( or little ) diffraction . Why throttle it back ? Certainly 8.0 would've helped your cause as many lens have a sweet spot between 4 and 8 . I 've gone to 12 with good results for similar pics .

What did you use for pics : jpeg -v- raw ? With what software ? DPP v4 works well with raw from 450's as I recall - free from Canon too . So many details left out . . .

So many things - so many variables to cover - so the answer is " or what " .

And let's face it - it could even be an equipment issue - it is old - although capable if in good condition .

We can do more if you give us something we can sink our teeth into without spinning wheels though the above should give you alot to consider .

I use central AF

My camera usually takes extremely sharp images, I just showed examples where images are not sharp because of focus miss. Images shown in example are taken with Canon EF-S 10-18mm F4.5-5.6 IS STM. I shoot RAW.

ohrid wrote:

It misses like without any reason in standard static scenes. It looks more like FF/BF but I tested lenses and they doing well. What do you mean "all AF points active"? I use automatic selection or single AF point from time to time.

Here are a few examples

https://photos.app.goo.gl/uurDU1YDmegbbMVJ3

The 1st image looks like it is misfocused AND some "camera shake", as if the IS was not settled yet when you took the image. You do not have the camera on "AI-Servo" AF mode, right? It should be in One Shot mode.

By the way, automatic AF point selection (all AF points active) is never a good idea, it will focus on the thing most in front (under one of the AF points, of course).

What happens when you press the shutter button twice (letting the camera AF twice) before pressing it all the way to take an image?

If all this is not the reason, it must be the camera/lens combination. I find it very odd that you have such severe issues with these lenses on the 450D. I know that some other lenses can have an issue with the 450D (I used to have AF inaccuracy with my 450D and Tokina 12-24mm f4), but I would not expect it with a 10-18mm IS STM.

In live view, the Tokina and my Sigma 18-50mm f2.8 EX DC would not focus accurately on my 450D. I now have a 6D , by the way.

Yes

As I tell camera most of the time takes good-focused shots, but sometimes happens such misses inspite af blinks red. I tested with Live view as you say. Result is the same. Mostly it is focused. But sometimes it is not focused.

Ps. Google compresses photos without any damage to IQ. It downscales to 12mpx if above, but Canon 450D is accurate 12Mpx

Here are some examples with the same af, but focused well

https://photos.app.goo.gl/2xsJ18cGHderPCNt1

ThrillaMozilla wrote:

You didn't give us quite enough information, ohrid. We don't know the shutter speed or the F number at which the pictures were taken.

The f-value is not important, and it and the exposure time are in the EXIF.

There are (at least) three possibilities, listed in no particular order.

1. Camera shake. You always have to hold the camera very steady. It's hard to know by looking at these pictures.

2. Camera not focused. On your camera the focus confirmation light is on the right, at the bottom of the viewfinder. You need to look for that or listen for the beep. If you can't get a focus confirmation in broad daylight with those pictures, then you have some kind of malfunction.

3. You say misfocused in viewfinder AND live view. That suggests that you need to hold the camera steady. But it's hard to know without more information.

4. You could be doing a backbutton focus but releasing your finger before focus is confirmed.