# Focus problem with 100mm



## taxi (Sep 9, 2014)

Took these shots recently and upon close inspection, I realize that AF has focused at the wrong spot.
The images are taken with 5dm3, 100mm at 2.8 and strobe. 

1st image - focused on the basil, but the sprouts were in sharp focus
2nd image - a close up of the same shot for clearer view
3rd image - focused on the mousse but the thyme was in sharp focus

What can do to correct this problem? Any tips will be helpful.
Thanks in advance.


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## rwmson (Sep 9, 2014)

I recommend manual focusing for macro shots.


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## rpt (Sep 9, 2014)

Have you AFMAed your lens? That may be the problem. Try live view focusing also - other than manual as rwmson suggested.


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## Maximilian (Sep 9, 2014)

taxi said:


> Took these shots recently and upon close inspection, I realize that AF has focused at the wrong spot.
> The images are taken with 5dm3, 100mm at 2.8 and strobe.


Hi taxi! I suppose the lens is a macro, 100 mm with or without L, because that is not 100% clear.



> 1st image - focused on the basil, but the sprouts were in sharp focus
> 2nd image - a close up of the same shot for clearer view


When I look at the basil, it is sharp - more or less. With f2.8 and at this close distance (< 50 cm?) you have almost no DOF and so just a little part of it is sharp. So here I don't see a technical problem comming from the AF. 
The sprouts are also sharp, because they are in the same focus plane. As they are filling more space in the picture they are distracting you to look at them. Difficult to say, what to do better here. 
With a T&S lens or by changing the angle of perspective you could have gotten the sprouts out of the focus plane.
Playing with the aperture could have given you more DOF and therefore the leaf of basil might become more prominent in composition.



> 3rd image - focused on the mousse but the thyme was in sharp focus


Here's something wrong with the AF. 
Maybe it failed with a BF issue. AFMA could help then.
Maybe you went beyond the MFD of the lens (approx. 30 cm).
Difficult to say.
But also again you have to think about the aperture and DOF.



rwmson said:


> I recommend manual focusing for macro shots.


100% agree.
live view, magnify the image, manual focusing, control the aperture, etc.

Try it out and let us know, if it helped.


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## taxi (Sep 9, 2014)

rpt said:


> Have you AFMAed your lens? That may be the problem. Try live view focusing also - other than manual as rwmson suggested.



Hi, what is AFMAed?
I didn't use manual focus, I center AF point, it should be the most sensitive AF point, but the image came out wrongly focused.


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## Marsu42 (Sep 9, 2014)

taxi said:


> What can do to correct this problem? Any tips will be helpful.



Don't forget that even with a premium camera, the tech still cannot read your mind. With multi af spots and an extremely thin depth of field, the camera is bound to make the wrong decision sooner or later. Better use one af spot so you know where the focus is supposed to end up, or....



rwmson said:


> I recommend manual focusing for macro shots.



... +1, esp. with Magic Lantern's focus peaking focusing tripod macro is much easier (and ML has focus stacking, too).



rpt said:


> Have you AFMAed your lens? That may be the problem.



While this for once really looks like a possible afma issue, setting this is not the solution to all problems. Esp. with a macro lens calibration is tricky since the required value depends on the object distance. At least with my 100L, I didn't find a single value that works at both near and far distances, so I calibrated for far and mf for macro (I could also switch the afma value with a key with ML).


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## taxi (Sep 9, 2014)

Maximilian said:


> taxi said:
> 
> 
> > Took these shots recently and upon close inspection, I realize that AF has focused at the wrong spot.
> ...



Hi Maximilian,

It is 100mm L lens. the image is not very clear bec, it is a screen shot.
I have used F5.6 for the same shot and it was fine. I don't remember now what was my distance to the food, I will only take the shot when I hear the focused sound. I thought that is the indication that the AF point is locked on.

Just tried f2.8 again to take some shots, it seems fine, the image is sharp at the selected AF point. 

Bec. I had to shoot fast, so couldn't afford to use manual focus. I will try that the next time and use live view as well.


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## awinphoto (Sep 9, 2014)

In these shots, i think AFMA is the issue, esp for the top 2 image... the 3rd, focus is (depending on how big they are, how far away you were) very close for arguements sake as far as the plane of focus side to side. The exact mouse part doesn't seem like there may have been enough detail for the camera to determine absolute perfect focus, but all things in consideration, without being there, it's hard to say one way or the other. Like other said, for food shots, especially if done for a client, live view and manual focus is king. Manual focus is a good rule of thumb for most macro shots regardless, although the AF is usually good in most situations, it's just better to have absolute control over the shot. And to answer your question, AFMA is auto focus macro adjust... in your custom settings you can use this feature to fine tune your AF performance if you find it consistently front or rear focusing... I'd use caution with macro stuff as to how it would preform on non-macro subjects, but it is something to consider if you do a lot of these style shots.


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## taxi (Sep 9, 2014)

Thanks, Awinphoto.

I think you are right, there is not enough details for the AF to lock in, therefore the focus shifted.
I just tried taking some shots at F2.8, the images are in sharp focus at the selected AF point.


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## rpt (Sep 10, 2014)

taxi said:


> rpt said:
> 
> 
> > Have you AFMAed your lens? That may be the problem. Try live view focusing also - other than manual as rwmson suggested.
> ...


http://www.the-digital-picture.com/Photography-Tips/af-microadjustment-tips.aspx
This is an article by neuro. This should help. You can look for "dot tune" on the Magic Lantern site http://www.magiclantern.fm and also look up focalweb/.

I purchased Focal. I have Magic Lantern on my 5D3 but have not tried dot tune.

Hope this helps... Let me know if you have any questions.


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## J.R. (Sep 10, 2014)

rpt said:


> I purchased Focal. I have Magic Lantern on my 5D3 but have not tried dot tune.
> 
> Hope this helps... Let me know if you have any questions.



Hi rpt,

I've tried dot-tune but the results were too variable and unreliable for me. Ever since purchasing Focal, I haven't looked back.

In the absence of Focal, manual empirical testing with different AFMA values is the best solution in my opinion. But it isn't easy to identify the sharp/sharper/sharpest photos using this method.


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## Logan (Sep 10, 2014)

the plane of focus goes through both parts of the picture. its a composition problem, other than that im not sure whats wrong.


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## rpt (Sep 10, 2014)

J.R. said:


> rpt said:
> 
> 
> > I purchased Focal. I have Magic Lantern on my 5D3 but have not tried dot tune.
> ...


OK, Thanks. Having heard that, I am not going to test it in a hurry and my expectations are not high.


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## tayassu (Sep 10, 2014)

Hey taxi 
I had exactly the same problem with the 100mm macro. I suppose you've been shooting on OneShot AF handheld? In macro, only 3mm shaking, which is perfectly normal, can make the whole picture blurry. Try Servo AF, it will work much better


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## rpt (Sep 10, 2014)

tayassu said:


> Hey taxi
> I had exactly the same problem with the 100mm macro. I suppose you've been shooting on OneShot AF handheld? In macro, only 3mm shaking, which is perfectly normal, can make the whole picture blurry. Try Servo AF, it will work much better


+1!!!

I presumed it was on a tripod. Please do let us know.


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