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02-17-2011, 05:14 AM   #1
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Manual focus on New cameras

Ok, so this may be a simple question, but I have been wondering how you would accurately focus a non-autofocus lens on a camera such as a K-5? Or really any other digital SLR.
I remember my film camera having a split viewfinder in the centre where I would focus so the two semicircles lined up - then I knew I had the correct focus and would take my picture.
Nowadays, if I look through my k100d and try to manually focus, I can get close, but never anything sharp. How do you guys with the old manual lenses do it?

02-17-2011, 05:21 AM   #2
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The fact is you will seldom get consistent focus with your manual lenses unless you swap out the original screen for a KatzEye or similar product. If you have a number of MF lenses you should give this serious consideration. There are several threads in the forum dealing with focusing screens.

Tom G
02-17-2011, 05:21 AM   #3
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You can get split image focus screens from people like Katz Eye and others. In addition here is a series of focus exercises that I have found really helpful. To give credit where credit is due, they were written by a poster over at dp review named Godfrey. They are boring to do, but they work for me.

"It's much easier to teach focusing in person. Writing up a procedure to do it is tedious. Happily, with a digital camera, it is easier to practice without wasting a ton of film in the process.

Here's a short sequence to experiment with:

- Start easy: Pick a medium focal length lens, like 50-70mm, and preferably a fast lens. (you can do it with a zoom set to this focal length too.

- Place a target about 2m away, separated from foreground and background. The target should be something with some surface texture to work with, or something with a mix of 6, 9, 12, 14 and 18 point font on it. Light it adequatelly for a wide open aperture and short exposure time (like 1/200 second). Lock in the exposure manually so it cannot vary on you.

- Get comfortable with the camera and set it to MF mode.

- Twist the focusing ring from infinity to closest focus at a medium speed. Then the other direction after a short pause. And again and again. Do it slow enough that you can watch the focus transition from blur to sharp to blur, but fast enough that the transition to critically sharp "pops" for a moment as you turn. OBSERVE the focus transition carefully, over and over again. Get a feel for how much time/how much angular displacement of the focusing ring causes how much focus transition to occur.

The trick is to look at a subject and know the lens well enough to turn the focusing at the speed which makes the sharp moment pop, and be able to stop PRECISELY at that point.

- Start trying to achieve that point of focus ... only turn in one direction and try to stop just once, make an. exposure. DON'T look at it immediately on the LCD ... it helps if you turn off the review function. You want to repeat from close limit and from infinity ten times each.

- Then download the image files to your computer and sort them into frame order. Look at them, one at a time, at 1:1 pixel resolution and mark down which are in focus and which are slightly off. Try to remember for each one what you felt as you stopped and made the exposure.

Repeat this exercise until you get nine frames sharp. Then repeat it again doing 20 frame sequences until you get 19 frames sharp. Do as many as you can but DON'T keep going until you get tired, stop and take a break for a little while. The point is to plant in your finger and eye memory how fast to turn the ring and how to stop instantly when you see the point of best focus, just once.

- Once you're doing sequences of 20 shots and getting them all in focus, double the target distance with the same lens and do the same exercise over again. Once you get 20 out of 20 with that repeatedly, you can double the distance again. It gets faster as you go along. By the time you get there, you should set up two more targets so you have three ... 2, 4, and 8m ... and do a couple of sequences where you focus on each one at a time ... put it in the center of the frame so you know which your focusing on ... and do the same sequence of 20 until you get them all in focus through the sequence repeatedly.

So now you know what it's like to focus that lens quickly and reliably, with your eye alone.

- Change the lens to a shorter focal length (say 28 to 35mm). Start at the beginning but use 1.5m as a starting point. Same rig, same target, different focal length ... the shorter the focal length, the more subtle the focus transition is to observe.

- Keep doing the sequences with shorter and shorter lenses until you get to the shortest lens you have. Realize that when you get down to the 18-20mm range, you have to accept either a slower pace or a few more erroneous focusing frames to "finish" a sequence.

This kind of skill does not take exceptional eyesight; it takes the ability to see the motion of the focus transition 'stop' or pop for an instant and the muscular ability to stop turning the focus ring precisely at that instant. I've been able to get perfect critical focus using it even when my glasses were covered with guck after a hot session on a sweaty day or I dropped them and could not stop taking photos for one reason or another. All you're looking for is that point of "pop" in focus as the image moves a tiny bit, and to stop your fingers at that moment, you're not trying to see the details.

I'm sure that if you go through this exercise with calm motivation, you'll find your manual focusing reliability improve ten fold in a day. I've been doing this so long and with so many different cameras that it just seems to come naturally to me. First thing I do whenever I fit an unknown lens to my camera is switch to MF and just rack it in and out from infinity to close limit focus a couple of times to "calibrate" my eye and fingers. Within a few moments of that, I'm ready ... I rarely get a bad focus, if I bother to look through the viewfinder and focus at all ...

Which is another story. "


NaCl( as they say "practice, practice, practice)H2O
02-17-2011, 05:29 AM   #4
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Thanks NaClH2O (and Godfery)!


02-17-2011, 09:29 AM   #5
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QuoteOriginally posted by NaClH2O Quote
NaCl( as they say "practice, practice, practice)H2O

NaCl - thanks for advise. Great practice steps. But i want to point out regardless how much you practice if you can't see clear enough in viewfinder you still get OOF pictures.

I also have hard time manually focusing on my K-X and after much research decided to change focusing screen first. There are several options available from what i learned (in order of preference):

1) Katz eye - most expensive one ($100+)
2) Focusing Screen (Taiwan based company) - some good quality screens ($45+), my favorite is K3 based on Nikon SLR focusing screen (~$85)
3) many Chinese made knockoffs starting $18+

Even though knockoffs will be real upgrade compared to original screen I think best route is to get one from Focusing Screen. First QC is better and they may use better materials(definitely K3 is really nice)

There is downside too - many complain about effecting camera spot metering and inability to use split screen in all F stops. But I still decided to change focusing screen - what's point of original screen if can't focus anyway?

I don't want to pay $80+ for Nikon based screen and decided to go DIY route. I ordered online old Nikon focusing screen (~18) and going to follow one of many tutorials available online. Never done it before but seems like an interesting project. Good luck (I need it for sure )

Last edited by Black_ronin; 02-17-2011 at 09:37 AM.
02-17-2011, 09:56 AM   #6
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I cut my own from an old M42 mount camera and then shimmed it with pieces of aluminum foil taped together. Much higher quality than the chinese knockoffs, and dirt cheap. I think it cost about $8 shipped.

Something like this, but not quite. The tips for cutting the screen are still applicable.
02-17-2011, 09:59 AM   #7
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I use manual focus almost all the time with my K20D and numerous lenses, even for BIF, simply because it is more accurate, reliable and often faster than AF. Google Ron Kruger and click on any link to Photoshelter to see examples. Hardly anything in there is AF.
A few months ago I got a Katzeye screen, thinking it would make it even better. It doesn't, at least not for me, and there are exposure problems with spot metering and long lenses. I really should sell it. I mostly find the split screen an annoyance, just as I did those blinking focus lights and beeping before I turned them off.
Good MF technique is partly technique, but mostly it is how and where you concentrate. Try narrowing your attention to a small part of the frame where you want to center the focus, such as an eye, while ignoring the rest. I trust this more than I trust concentrating upon lining up those lines on the focus screen.
02-17-2011, 10:28 AM   #8
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It isn't as good as the split-screens, but in most cases, the AF sensors will work for focus confirmation on MF lenses.

02-17-2011, 10:46 AM   #9
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I only shoot manual, don't have a new screen, and accurate focus isn't a problem. FAST focus is, but that's a problem with some AF lenses too,

I'll soon be rigging all of my M42s with aluminum tape at the base to see what the excitement of catch-in focus is all about. For many shooters here, this seems to be the best invention since sliced bread, and I have no experience or reasons to dispute that.
05-12-2011, 01:07 AM   #10
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Shots out of focus with M lens, but OK with new ones.

I got bunch of great old glass. Mostly Takumars and Helioses. But I get focus wrong with my k-5 pretty consistently. I have installed split-prism focus screen and I am very familiar with its usage from 30 years back.
Do I need to adjust the camera for each lens (actually I do not know how) or there is a problem with the camera itself?
All my new DA lenses focus right on spot.
05-12-2011, 02:45 AM   #11
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QuoteOriginally posted by vanakaru Quote
I got bunch of great old glass. Mostly Takumars and Helioses. But I get focus wrong with my k-5 pretty consistently. I have installed split-prism focus screen and I am very familiar with its usage from 30 years back.
Do I need to adjust the camera for each lens (actually I do not know how) or there is a problem with the camera itself?
All my new DA lenses focus right on spot.
There are a couple of problems with split-prisms and replacement screens.

Firstly, the split images need to be very accurately aligned for really accurate focusing.

Secondly - and this is a much more serious problem - when you install a new screen, you may well need to re-shim it for it to be in the correct position (and it only has to be out by a few microns for you to lose decent focus). Apparently, even the expensive screens can - and do - suffer from this. (Hopefully, all replacement screens will have their focus aids (i.e. split-prisms) harmonised with the screen itself, so you can focus accurately either using the aid or the screen itself - once you have the correct shimming.)

As I've said before on these forums, this is, for me, a major deterrent from installing my (cheap) replacement screen. So, I'll just have to continue soldiering on with the stock screen - though it certainly slows me down. For me, accurate manual focus requires a lot of effort (despite being very familiar with the techniques, from my film days).

As for using the green hexagon for focus "confirmation", in general, it just doesn't work anywhere near accurately enough (on my K-m, which autofocuses extremely accurately). However, it does seem to be able to do a reasonable job for some lenses, notably my 50s. This implies similar results for Catch-in-Focus.

So, pmastello, I would stick with the stock screen if I were you, and follow the advice given by that Godfrey chap!
05-12-2011, 03:05 AM   #12
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For still subjects, and a body with liveview, why not use liveview and magnify the view?

Another alternative is one of those Chinese right angle finders which can switch to a magnified view. I think a magnifying eyepiece is also one of the standard Pentax accessories.
05-12-2011, 03:50 AM   #13
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There are a lot of good advices here, I'll try them for sure.
To me one another good point is the live view, I think that it can help if you zoom in to the details.

I really like my Pentax K 55mm 1.8, but my focusing ability is really poor.
05-12-2011, 05:58 AM   #14
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there is a lot of good advise in the posts so far.

I have a large collection of manual focus lenses (~30) and use them regularly in my K10D and *istD.

I bought from jinfinance, a single diagonal split image for my K10D and a dual split for my *istD.

I have also discussed with rachel katz, the possibility that katzeye would develop a diagonal split (this is a personal preference for me, dating back to my ricoh XR-2s) Rachel said that a diagonal split, or I believe more ccurately any split that does not intersect a focusing line at 90% that it is not as accurate, because the eye has less ability to detect minor errors. I tend to agree, however, I find the dual split, seems to be much more accurate in this regard.

ALthouth others have needed to shim their screens I have been lucky enough not to. I attribute this to my cameras having penta prisms,, which may need less shimming inherently.

I alsoi use MF lenses with my K7D and the stock screen, and while it is harder, it is not impossible, but you tend to rely more upon the focus indicator, especially with wide and ultra wide lenses.

With the split image screens,
- yes the center can darken at F5.6 and above, and also in low light.
- yes spot metering is essentually useless.

but on the K10D, which metered very badly any way with manual aperture lenses, the loss is not critical as long as you check your lenses before hand.

Regardless of what screen you get, a split image will enhance the use of MF lenses. The debate has raged on for a very long time as to whether any one is better than another, or whether the price of a Katz eye is justified, relitive to any better performance , against the chineese screens. I won't attempt to answer, but I am sure most people are pleased with what ever screen they bought
05-12-2011, 12:43 PM   #15
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I love my old MF lenses, but I really have a difficult time seeing the image clearly enough. I've thought of the magnified eyepieces, but I wear glasses and most people report difficulty in using them with glasses. And split screens seem to cause issues with metering etc.

One exciting possibility is found here, which is also good for fast (<1:2) lenses. https://www.pentaxforums.com/forums/pentax-k-5-forum/142241-best-screen-ever-...anon-ee-s.html
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