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Thanks useful information: 5
As the title suggests, I suck at manual focus! Of the MF photo's I take, around only 10% are any good! Is there a secret to it? Is it because my eyesight is a little poor (I wear glasses)? I'd prefer not to use AF because it sometimes focuses on the wrong thing, and can be a little slow at times...
Any advice would be greatly appreciated?
Cheers, Michael.
Nikon D3100, Nikon DX 18-55, Nikon DX 55-300
Make sure that the diopter adjustment on your viewfinder is set correctly.
Using Live View at full magnification, focus on a solid object, lock the focus (by making sure the lens is on manual focus), then look through the viewfinder and adjust the diopter adjustment so that the object is in perfect focus through the eyepiece.
The diopter adjustment is usually a little wheel beside the viewfinder.
It's easy for it to get knocked too, so when you have it perfectly adjusted put a little drop of white paint of white out on it so you can easily see if it has been moved.
I grew up with manual focus, so I find it quite comfortable, but if your veiwfinder is not adjusted properly, it can be impossible to focus as everything looks fuzzy - in focus or not.
Otherwise, use your auto-focus, but set it to do spot focussing (using just one focus point).
All my photos are taken with recycled pixels.
Knowledge is knowing that a tomato is a fruit.
Wisdom, is knowing not to serve it in a fruit salad.
I think most people will find that focusing manually, through a viewfinder, is a skill which takes some practice to master. I've been focusing manually since the early 80's and it is by far my preferred method of operation, particularly where the depth of field is very shallow and accurate focus is most critical.
MF will be affected by many factors and in the best circumstances can be relatively easy but in poor circumstances can be extremely difficult at best.
Some cameras, in fact almost all amateur cameras, are not designed to be very good at MF as most amateur cameras are used with AF so manual focus is not a big issue. They typically have a small viewfinder, low image magnification, and a focusing screen designed to give a bright image rather than one which allows accurate focusing (they are not the same thing). Modern 'pro' cameras such a 1ds3 (and similar) are designed to focus manually. Intermediate cameras like the 5d2 can be quite poor. I regularly use a 5d2 and have difficulty with it if focusing through the viewfinder (Live View is another matter). Some times you can replace the focusing screen in the camera to improve focusing accuracy, at the cost of brightness, and I certainly recommend doing that if you intend to use MF regularly.
The lens you are using will also be a major factor. Consider that the image you see when focusing is the image that the lens creates when it is wide open. Most lenses are not at their best when wide open and some can even be a bit fuzzy/poor so if you are already focusing with an image which is not very sharp then the task becomes even harder. A high quality lens might have a better image when wide open so focusing can become much easier. The maximum aperture of the lens will also be a factor. An F1.4 lens will obviously give a very bright image but the image might not be as sharp as that from a similar but slower lens, say a macro. It’s not exactly a ‘trick’ but you can use the depth of field preview function on a camera to stop it down one or 2 stops and focus that way, giving you a sharper image with which to focus. The other extreme is the kit lens which is typically not very sharp wide open and then usually very slow as well. Frankly you are pushing shit up hill with these. There are other factors too, such as field curvature and focus shift, walk first, run later.
Even in the best conditions you need to practice to recognise what a sharp image looks like in your camera. There's always a certain amount of 'wiggle' room where the image may not really seem to change very much but in fact the image will have changed significantly. Recognising the exact point where the image is perfectly focused with your camera may take some practice and comparing it to what you see in Live View is a good way to check how you are performing.
If you wear glasses then remember that the image you are viewing corrected to appear approx 1m away so you need your distance, not reading, correction.
JJ
Last edited by jjphoto; 24-06-2012 at 9:02pm.
^^
And if you need to ask more, go ahead.
Am.
CC, Image editing OK.
You seem to have AF lenses. - why are you manually focusing or at least trying to ?????
It may be easier ato sharpen up your AF skills instead to get that faster and more accurate
Last edited by mongo; 25-06-2012 at 9:09am.
Nikon and Pentax user
I don't know why you are trying either, I thin I would stick to af and learn the more impotent things that drive your camera.
If I use manual focus with the 7d when the subject is in focus the focal points threw the view finder blink to tell me that it is focused
Canon 7d efs 15-85mm, Sigma 150-500mm. Nicon coolpix 5400
John(jjphoto) described the issue pretty well with the main issue being the viewfinder in the camera as the main culprit.
I changed my focusing screen on my D300 to one from KatzEye, and it's so much easier to manually focus any fast lens because of that.
Just changing the focus screen to one that's apparently better for manual focusing is not the answer tho.
Prior to getting the KatzEye screen, I also got a cheapie $30 from ebay for my D70s and apart from the split prism aide, it isn't really that much better for focusing manually.
I haven't really noticed that the Katzeye screen has darkened the D300 all that much, but I did opt for the expensive optibright version of the screen too.
Part of the problem is that in most screens, to achieve a decent brightness level, the screen has a lower contrast level, which then gives a deeper observable DOF through the viewfinder.
This lower contrast screen means that what you observe as the DOF is approximating an aperture value of about f/5.6.
So if you shoot at f/3.5, then what you see(f/5.6) and what is really happening optically (f/3.5), where you think you are in focus, the optics may not agree!
Using a higher contrast screen matte(the fuzzier part of the screen), which gives you better definition as the subject comes into focus, also means that the view is also more dim.
Another thing that we really don't want is dimmer view through an already small and dim viewfinder.
But as the contrast is higher between zones of depth, the subject comes into and out of focus more clearly through the viewfinder.
That is, what you see through the vf, is more in tune with the actual optics.
If you can spare the expense, a KatzEye, or similar high quality focusing screen will help immensely.
Nikon D800E, D300, D70s
{Nikon}; -> 50/1.2 : 500/8 : 105/2.8VR Micro : 180/2.8 ais : 105mm f/1.8 ais : 24mm/2 ais
{Sigma}; ->10-20/4-5.6 : 50/1.4 : 12-24/4.5-5.6II : 150-600mm|S
{Tamron}; -> 17-50/2.8 : 28-75/2.8 : 70-200/2.8 : 300/2.8 SP MF : 24-70/2.8VC
{Yongnuo}; -> YN35/2N : YN50/1.8N
The "green dot" focus indicator is not always that accurate and also, one of the reasons for manually focusing is because the AF point is not in the area that you want to focus on, which means that the green dot focus indicator would be useless.Originally Posted by ving
My PBase site: http://www.pbase.com/lance_b
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Auto focus lenses are not always the easiest to focus with as their "focus throw", ie how far you have to turn the lens to move focus fro nearest to infinity, is very very short, which is great for fast focusing using the AF. However, the downside is that you have very little accurate fine focus control which used to be afforded with those beautifully engineered manual focus lenses we used to use. If you look at the focus throw of a modern AF lens, you will see that it probably may go from closest to infinity focus by a mere 25-30 degrees turn of the focus ring, whereas an old manually focusing lens will probably turn a good 120degrees or even more! This gives you very accurate fine focus control.
So, as with what Arthur said above, not only do you have a more difficult VF to focus with due to the way the ground glass screen works, but your lenses are not even remotely easy to do any manually focusing with. I would suggest that if you can get a decent manual focus lens of yore, you may get better results, but from what I know (but I may be wrong), your D3100 may not recognise the aperture settings of the manually focusing lenses and thus will not meter correctly. You are in a catch 22 situation. I do know that the higher ends models from Nikon will allow for use of the manually focusing lenses.
This is what I do.
I use single center focus point then focus on subject and while still holding shutter button i then compose the shot
Last edited by Duane Pipe; 25-06-2012 at 5:08pm.
How do you adjust the diopter settings? Doesn't matter where it's set to it appears to make no difference.. through the viewfinder at least...
Apologies for what I'm about to explain, as it may seem a bit contradictory.
While it's still true that the green dot range finder is not entirely accurate, you can use a method whereby it becomes 'accurate enough' to be close to spot on .. but only if you have the time to work at it.
The problem with the range finder green dot focus confirmation is that most people will jiggle the focus to and fro. That is back and forth until the focus light comes on and the image looks in focus.
This is where I had lots of issues with my fast lenses, and changed my focusing method(but I also did some hardware tweaking) to get it close to spot on too.
The focus confirm indicator can be accurate as long as you always focus to the focus point from the same direction.
I don't think the direction is important, but you need to choose one direction and stick with it.
What this means is that you have to teach yourself to focus to the subject with the lens pre set with the focus set to either MFD or infinity.
My preferred method was always from near to far. So that if I manually focus, I always pre set the lens to the closest focus distance and then focus out towards the subject.
The range finder confirm light has too much tolerance allowance for it to be accurate.
I had a hell of a time trying to use it with the 50/1.2 as the difference between confirmed or not, can be significant to a noticeable degree.
I soon practised to the point where in focusing from near to far I almost always got spot on or near enough that it didn't make a difference.
Focus slowly and smoothly from (in my case) near to far watch the focus confirm light come on and you could be close enough get a decent shot.
My practising method was to use an inanimate object, tripod mounted camera and brightly lit scene. The subject had to also have a shape or form that allowed me to view any focus inaccuracies instantly and by how much it was out.
(I used the corner of a wicker basket as the subject .. the corner I think).
So if your camera has live view, this makes it super easy peasy to do.
You decide to do this focusing from which ever direction feels the most natural. Camera is set on tripod, low ISO if shots need to be taken to confirm the focus.
Defocus the lens fully in the direction you prefer and then slowly focus towards the subject. You need to be very careful that your focus point is only seeing the subject that you want to focus on and that it doesn't stray around that in any way.
Once you focused to the subject, leave the camera and enable live view. If live view doesn't give you enough resolution to confirm that focus is hit or missed, then take a snap of the scene making sure that camera shale doesn't then kill the image too tho!
If live view is high res enough, before you try again, move the focus collar very slightly this way and that to confirm that better focus can't be achieved.
if it can practise again.
If you find that a better focus can be had in the majority of attempts, then this is where your ability to learn becomes very important.
(this is what I initially did):
You now need to try to pre empt focusing perfectly by partially ignoring the focus confirm light and focusing to the point on the lens where it is spot on.
So, in my case with the 50/1.2 I had to focus the collar just a wee smidge past the point where the light came on.. maybe 1/2 - 1mm on the focus collar.
It sort of feels wrong, but it works and you need to commit this to long term memory.
Mine being so flaky, I looked for alternative options, and initially this was to adjust the primary mirror stop in the camera to where the focus point coincided with the rangefinder light.
Then later on, I got the Katzeye screen, and the had to undo the mirror stop adjustment as it was out my that 1mm I set it too.
Lance is right, old manual lenses are much better for manual focusing and can be had for a song.
D3100 won't meter or recognise the lens's stats in any way.. but on the bright side you can mount ANY!!! F-mount lens, and there are plenty to be had for next to nothing on ebay.
Any non Ai lens will fit without any damage to the camera, and can be had to prices as low as $5-10 from anywhere around the globe.
Some are very good lenses, others are so so.. and I'm always on the lookout for something else.
Non D40/60/3100/3200/5100/5200 camera owners can have trouble fitting an non Ai lens to their camera.. it can damage the camera!
Your D3100 is perfectly fine except for a very few examples of lenses that simply will not fit, but these are rare and expensive lenses .. almost certainly not something you may even find easily too.
If in doubt just ask. As an example of the type of lens you need to watch for, is the very early short back focus fisheye lenses. These have long protruding rear lens elements that will destroy the mirror in any Nikon camera and cant' be fitted to any without some preparation. They are obvious to see tho.. the long rear protruding element is blindingly obvious.
So while there are exceptions, the vast majority of lenses will fit onto your lil D3100
Harder to use, but you get used to it eventually.
A 50/2 pre Ai, may set you back $10 or so!
Some really nice pre Ai 50/3.5 micro's can be had 'quite cheaply' too that I've seen .. $30-50 easily found.. some more, some less.
The diopter is not related to the focusing system. It is on the side of the mirror prism and is used to adjust the focus through the viewfinder for those with less than perfect vision. See you user manual for details on how to adjust based on your eye prescription
"It is one thing to make a picture of what a person looks like, it is another thing to make a portrait of who they are" - Paul Caponigro
Constructive Critique of my photographs is always appreciated
Nikon, etc!
RICK
My Photography
Dipotre setting makes no difference to where the focus should be.
It should always be set to display sharply focused viewfinder information details.
If they are a bit unclear than it makes a difference to focusing but only where you think it may be.
I think I get about three clicks where there seems to be no visible difference to the sharpness of the vf information indicators. So with that I always set it to the middle position...
ie. with the thinking that this is the best average point to where it should be set to.
Just on that, is that adjustment meant to allow for prescription without my glasses on or adjusting whilst still wearing glasses?
If you normally wear glasses for normal vision leave them on. If you only need glasses for reading leave them off. Multi vision glasses can cause problems as you must be sure you are looking through the normal vision area when adjusting the Diopter.
Keith.
To adjust thee dioptre, it is best to look at a plain white wall with no features on it, or a blue sky,move the dioptre and bring the lines on the focus screen as sharp as possible, with out spectacles, there may not be enough
adjustment, for some, this could help in manual focusing.
I have only just started to learn how to use the manual focus with my shorter lens and I can already see its benefit in allowing me to focus on just one (and the most important) area in my photos...especially for close up work. Will it be more difficult for me to focus manually with my longer lens? I thinks I'll have to make it a point to practise. Thanks for all of the above information.
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