# why is my focus ring not working?



## ph0toe (Mar 21, 2021)

trying to use manual focus. i have the 24mm-105mm lens switched from auto to manual. i also switch to viewfinder /video live view and magnify x5 to zoom in and then turn the focus ring but it isn't getting sharper. what am i doing wrong?

using mark 3 5d


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## weepete (Mar 22, 2021)

Are you closer than the minimum focus distance of your lens?


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## ph0toe (Mar 22, 2021)

weepete said:


> Are you closer than the minimum focus distance of your lens?



hi, thanks for the reply. can you explain to me in baby terms what that means? always confused by that. why each lens have different minimum focus?


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## petrochemist (Mar 22, 2021)

ph0toe said:


> weepete said:
> 
> 
> > Are you closer than the minimum focus distance of your lens?
> ...


The amount of movement a lens needs to focus will be dependant on it's focal length. Macro lenses are typically designed to focus closer than other lenses, it's just one of a host of parameters that are optimised by the manufacturer based on how the lens is expected to be used.


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## ph0toe (Mar 22, 2021)

petrochemist said:


> ph0toe said:
> 
> 
> > weepete said:
> ...




so what about a zoom lens? it can focus in and out as far as it allows (for me 24mm-105mm) , which is a large range. 
is there a minimum focus distance for 24mm, to say 50mm to 85mm to 105mm?

and if so, what is it?


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## petrochemist (Mar 22, 2021)

It sounds as if you might be confusing the zoom control which changes the lenses focal length (& so it's field of view) with the focus control.
Most manual zooms are designed to have the same focus settings at all focal lengths, AF zooms can vary slightly but it's usually fairly small amounts.
I do have one adapted lens where the zoom control makes a vast difference to the focusing distance, zoomed out it's macro only, zoom in far enough and infinity focus is possible, this is usual for lenses mounted on extension tubes but not to anything like this extent.

I don't have a 24-105 of any type in my lens hoard. I do have numerous 70-200 lenses & the minimum focus distance of each design will differ. Some will go into a pseudo macro mode at one end of the zoom & allow much closer focusing in this mode.

I did a quick google for canon 24-105 lenses & found the specs. of one version which quotes the minimum focus distance as 450mm (about 1.5 ft) I believe the Mk2 version is similar.

This is probably a limitation required for it's large zoom range as my 24mm prime focuses to less than half that, though the focus distance is fairly typical for 200mm lenses.


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## Scott Whaley (Mar 22, 2021)

ph0toe said:


> trying to use manual focus. i have the 24mm-105mm lens switched from auto to manual. i also switch to viewfinder /video live view and magnify x5 to zoom in and then turn the focus ring but it isn't getting sharper. what am i doing wrong?
> 
> using mark 3 5d



Try connecting it to the camera....  Just kidding.


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## wfooshee (Mar 22, 2021)

Don't confuse focal length with focus distance. The 24-105 has nothing to do with the actual subject distance, that's just a measurement of the lens's focal length, which is a measure of it field of view, with a smaller focal length having a wider view.

A zoom lens set at 24mm focal length will not be able to focus on something only s4mm away.


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## weepete (Mar 22, 2021)

ph0toe said:


> hi, thanks for the reply. can you explain to me in baby terms what that means? always confused by that. why each lens have different minimum focus?



Minimum focus distance is the closest your lens can be to a subject and still focus. If you are closer than that you won't be able to focus at all, and need to move the lens further back.


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## ph0toe (Mar 23, 2021)

so from my understanding, every len has a minimum focus. as petrochemist alluded to, the specs for my len is about 1.5 ft. so moving my camera mounted on a tripod 1.5ft away or further should result in the image focusing. 

with all the parameters (iso, shutter and iso) in my environment figured where the light meter dialed right at 0, i should get a correctly exposure clear crisp image, right?


well when i tested this using manual focus and then magnifying it on my camera , it is very blurry. i see people able to just tilt the focus ring which is the closest turn knob ( shows macros to infinity), it doesn't change the focus. not being to achieve this means if i want to shoot product photography, or if i want to shoot video and have it focus on a subject eye for example i am at a stall....


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## weepete (Mar 24, 2021)

Does your autofocus work? Can you manually focus on something much further away?


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## ph0toe (Mar 24, 2021)

weepete said:


> Does your autofocus work? Can you manually focus on something much further away?



 autofocus does work. when i snap a picture on af it beeeps indicating so, and the image turns out sharp ,which is to be expected


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## SquarePeg (Mar 25, 2021)

Pick a focus length on the zoom.  Back away from subject, auto focus, turn on m focus, gradually move up and adjust m focus ring (not the zoom) until sharp.  Keep moving forward until you reach the closest point where you can still achieve sharp focus.  That’s as close as you’re going to get.  You can play with the zoom to see if that makes a difference in getting you closer.  Keep in mind that most zooms are not at their sharpest at either extreme.


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## ph0toe (Mar 25, 2021)

SquarePeg said:


> Pick a focus length on the zoom.  Back away from subject, auto focus, turn on m focus, gradually move up and adjust m focus ring (not the zoom) until sharp.  Keep moving forward until you reach the closest point where you can still achieve sharp focus.  That’s as close as you’re going to get.  You can play with the zoom to see if that makes a difference in getting you closer.  Keep in mind that most zooms are not at their sharpest at either extreme.




hi thanks so much. however, when when i manual focus and then i magnify it using the button near viewfinder it is blurry when i try to move my camera closer it is still blurry no matter how much i change the focus ring where it says the number in meters all the way to infininity. i try to adjust the diaopter to seee if it fixes anything (it is clear for my eyes on the viewfinder, not blurry, so i know this is not thee issue)


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## SquarePeg (Mar 25, 2021)

ph0toe said:


> SquarePeg said:
> 
> 
> > Pick a focus length on the zoom.  Back away from subject, auto focus, turn on m focus, gradually move up and adjust m focus ring (not the zoom) until sharp.  Keep moving forward until you reach the closest point where you can still achieve sharp focus.  That’s as close as you’re going to get.  You can play with the zoom to see if that makes a difference in getting you closer.  Keep in mind that most zooms are not at their sharpest at either extreme.
> ...



did you follow the steps above?


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## ph0toe (Mar 26, 2021)

yes i did, i picked a focus length of 50mm. i backed away from the subject (being the object), i autofocus then switch to manual focus and then i moved closer and adjust the focus ring and it isnt sharp.


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## SquarePeg (Mar 26, 2021)

how much closer?  1 step? 1 inch?  Try it without moving closer.  Can you focus manually then?  I can't really think of any circumstances where auto focus would work and manual focus adjustments would immediately make it blurry unless you are either moving the af ring too much or moving too close.  Maybe you should post one of these blurry photos along with your settings.


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## weepete (Mar 26, 2021)

Is your lens able to manually focus with distant objects? Say 300ft or so.


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## petrochemist (Mar 26, 2021)

ph0toe said:


> yes i did, i picked a focus length of 50mm. i backed away from the subject (being the object), i autofocus then switch to manual focus and then i moved closer and adjust the focus ring and it isnt sharp.


As has been pointed out earlier it's NOT 'focus length' of 50mm, it's a *focal* length of 50mm (close to the field of view of he eye). If you can focus on things at least 2 foot away all the way out to infinity the lens is working fine. This lens doesn't focus close up, 'moving closer' is your problem - with the lens zoomed to 200mm it will make items look closer while still being further away.


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## ph0toe (Mar 27, 2021)

Dropbox - IMG_0612.MOV - Simplify your life


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## wfooshee (Mar 27, 2021)

I have no idea what you were trying to show us in that video, or why we had to have the second half of it looking at the floor.

The 50 on the lens IS NOT the distance to the subject!!!! The distance to the subject is in that little window on the top of the lens barrel.

Also, zooming in the display in Live View is a digital zoom, and getting "blurry" is _normal_ for that. It's not really zooming, it's enlarging a section of the image, blowing up pixels and all as it does so.

If you're thinking you can focus on something that 50mm away from the lens, then you need to reset your expectations. The closest it will go is whatever the smallest number is that shows in that windows on top of the lens.


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## ph0toe (Mar 31, 2021)

I tried refilming and reuploading.. but it keeps crashing 
anyways, yes i am aware that the 50 on the lens is not the distance, it is just the focal length. at 50mm, its basically what the human eye sees. any less makes it wider and everything seen and any higher makes it possible to take a picture very far away (telephoto) 

so the number on the focus ring indicate the distance to subject from the smallest being .7 to infinite. 
now my question is why am i unable to turn the focus ring knob and get it in focus? i thought it was problem with the diopter but i set it so my eyes can see very clear through viewfinder..


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## weepete (Mar 31, 2021)

It's possible that your focus ring is broken, but you should try and rule out human error first. Most often people don't realise that you have to be a decent distance away from the subject for lenses to focus, unless you are using a specialist macro lens. So it's very common to see that error.

You should establish if your focus ring works at all by trying to manually focus on something much further away. If it doesn't it's probably broken, but if it does focus on something far away, you are probably still too close to your subject and need to move the camera back.

Bear in mind that modern focusing systems in modern cameras are really meant to be used with autofocus, and are not as easy to use with manual focus as the old split prism viewfinders. Though there are times when MF can come in useful.


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## wfooshee (Mar 31, 2021)

Does that number in the window change when you turn the focus ring? Does it change if you allow the lens to autofocus on something very far away, and something just a few feet away. Can you shift that focus with the focus ring?

All of this should be done looking through the viewfinder. I'm still of the opinion that using Live View to focus isn't telling you anything, as "zooming" in on the live View image is not really zooming, it's just enlarging and pixelating.


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## SquarePeg (Mar 31, 2021)

OP you haven't really answered any of our questions - you keep posting the same info/statements.  Can you manually focus on something far away?


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## petrochemist (Mar 31, 2021)

wfooshee said:


> I'm still of the opinion that using Live View to focus isn't telling you anything, as "zooming" in on the live View image is not really zooming, it's just enlarging and pixelating.


If your screen resolution is less than the sensor resolution there's no pixelation on initial zoom.
My eyesight is not bad, but I certainly find it easier to check focus on a zoomed screen, portions that look sharp enough in the viewfinder are often soft when printed to A4. Zooming the live-view image can enable focus to be pinpointed.
My experience with hundreds of manual lenses confirms it works brilliantly!


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## wfooshee (Apr 1, 2021)

Agreed, but it depends on how far you zoom, and I'm frankly not trusting the information we're getting from the OP. I use Live View zoomed in to focus on infinity for astro photography.

My statements about his zoom are based on, "It gets blurry," which I'm interpreting as, "It gets pixellated."


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## petrochemist (Apr 1, 2021)

wfooshee said:


> Agreed, but it depends on how far you zoom, and I'm frankly not trusting the information we're getting from the OP. I use Live View zoomed in to focus on infinity for astro photography.
> 
> My statements about his zoom are based on, "It gets blurry," which I'm interpreting as, "It gets pixellated."


Thanks for the explanation, your interpretation is somewhat different than mine, but you could be right. If the OP shares some examples we should be able to tell


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## stevet1 (Apr 1, 2021)

ph0toe,
Do you have the lens electronic MF enabled in your menu settings?
If so, I think you have to press your shutter button halfway and hold it , or your AF-On button and hold it in order for your manual focus to work (assuming you still have the switch on your lens switched over to AF.)
Steve Thomas


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## ph0toe (Apr 1, 2021)

wfooshee said:


> Does that number in the window change when you turn the focus ring?



YES



> Does it change if you allow the lens to autofocus on something very far away, and something just a few feet away. Can you shift that focus with the focus ring?



so i find that for autofocus instead of manual focus, if i go too close even when zoom in i am unable to take a picture because im assuming its due to the distance. when i move further away, i am able to.

All of this should be done looking through the viewfinder. I'm still of the opinion that using Live View to focus isn't telling you anything, as "zooming" in on the live View image is not really zooming, it's just enlarging and pixelating.

i find that when i "zoomed" in using the zoom lens i constantly have to adjust to get it in focus/sharp. is this normal? why cant i hold focus at say my desginated 35mm ?


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## wfooshee (Apr 2, 2021)

You _still_ haven't told us how close you're trying to get to the subject, and that is the MAJOR question everyone has. Most lenses have a minimum focus distance, where nothing inside that distance can be placed in focus. That distance changes with the zoom setting.

It's perfectly normal for a zoom lens to be able to focus on something close at the 24mm setting, but be unable to focus that close at the 70mm setting. It's also perfectly normal for some zoom lenses to not hold focus as you change the focal length; technically, that makes it a vari-focal lens, not a zoom lens, but the actual use makes no difference. ( "true" xoom does not change the focus distance as the focal length is changed, but many current lenses do, as that makes them less expensive.)


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## SquarePeg (Apr 2, 2021)

This is my last post in this thread unless you can provide straight answers to the following questions.

1 - can you use manual focus to focus on something far away?
2 - exactly how physically close are you from the subject (in feet/inches or meters) when you are having issues manually focusing?


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## snowbear (Apr 2, 2021)

SquarePeg said:


> OP you haven't really answered any of our questions - you keep posting the same info/statements.  Can you manually focus on something far away?





SquarePeg said:


> This is my last post in this thread unless you can provide straight answers to the following questions.
> 
> 1 - can you use manual focus to focus on something far away?
> 2 - exactly how physically close are you from the subject (in feet/inches or meters) when you are having issues manually focusing?



Maybe it's time to just lock the thread if the questions are not actually answered.


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## ph0toe (Apr 2, 2021)

I know a lot of what was said here was reiterated

Dropbox - IMG_0662.mp4 - Simplify your life


but to answer ya'll questions , when you say manually focus, I imagine stationary and it not continiously tracking. in that case yes i am able to manually focus. i noticed when i move closer it wont focus, so i can understand what you mean by there being a focus distance for every lens. when i move oh so slightly away i can focus and i get the sounded beep. however, the image is STILL NOT as crisp as i would like it, and that might be something to do with my ameatur skills, or something else

in terms of inches/feet i dont know how to measure that off the top but if you review the video, you'll see how close/far i am away from subject (bag hanging off the door knob) . i know thats not really helpful but it is the best i can show. fyi my room is around 12 x 11inches so from one end to another give or take.


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## weepete (Apr 2, 2021)

read up on depth of field.


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## ph0toe (Apr 3, 2021)

I did. aperture affects dof.since mine could only go as far down to 4.0, i wont get a shallow dof to say a 2.8. but it should focus on subject and blur background a bit as opposed to say a f/11. what am i missing here?


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## SquarePeg (Apr 3, 2021)

ph0toe said:


> the image is STILL NOT as crisp as i would like it, and that might be something to do with my ameatur skills, or something else



This is likely due to your settings and/or shooting stance if you are hand holding or due to lens vibration if you are on a tripod and didn't turn off VR.  Too slow shutter speed or too high ISO can reduce sharpness.  Post a photo along with your settings so we can take a look and try to help.


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## weepete (Apr 3, 2021)

The closer you are to a subject the thinner your DOF is, at minimum focus distance your DOF will be very thin even with a small aperture. That means you can't hold focus over a large area and you need to refocus the lens. That's just optics.

At a focal length of 105mm and an aperture of f4, when you are 0.7m away from your subject your DOF will be 0.01m (10mm). You'll need to keep your shutter speed up as well, so use at least 1/100th of a second,  1/200th would be better to eliminate camera shake. You won't be able to hold focus over a large area.

My advice is to get an actual subject, buy a cheap action figure off ebay or use a flower or something and try that.


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## ph0toe (Apr 6, 2021)

Dropbox - IMG_0662.mp4 - Simplify your life

thank you for your patience


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## wfooshee (Apr 7, 2021)

That's definitely not too close for the lens, nor are you zooming to the point of pixelating the image in Live View, both of which are what we were thinking might be happening. It's also suspicious to me that when you touched the shutter button to display your exposure setting in the top LCD screen, the lens did not focus, and you hadn't switched from AF to MF yet, nor had you turned on Live View. It should have focused at _that_ point.

The number "1" that you pointed out indicates that the lens is focused at 1 meter, which is much closer than the subject. A later glimpse of that window after you'd half-pressed the shutter button but before you switched to manual focus shows the distance scale in the same position, meaning the lens did not focus. That windows indicates the distance to which the lens is focused. On "1" something 1 meter away should be in focus.

Later, when you turned the focus ring it did adjust the distance scale, but it appears nothing changed in Live View. That tells me that something's wrong with the lens. When you manually focus while looking through the viewfinder instead of Live View, does it focus, or is it the same behavior? Is this your only lens? If you have another lens, does it exhibit this behavior, or does it work correctly?


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## weepete (Apr 7, 2021)

Yup, looks like the the lens is bust. That turn of the focus ring should have thrown it way out of focus and then back in, it seems like you are seeing no change. It may be that BBF has been enabled, and that could explain why AF doesn't work with a half depress of the shutter, but everything else in your video is pointing to a lens with a broken focusing system.


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## FrancisM (Apr 25, 2021)

I don`t know the situation but check this


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## cdd29 (Jul 14, 2021)

Older thread but just a thought... do you have another lens you can try?


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