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08-18-2009, 07:23 PM   #1
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Shoot manual 50mm

Hello everyone,

So I got this new used prime from a fellow member. And I was ready to go hiking with it. No luck with moving water shots because it too dry in NorCal. Anyways, I after a long long exhausting hike, I got home to upload some pic to my unpleasant surprise some shots were blurry. Through the view finder everything looked in focus and I even got focus confirmation.

I did read the shooting manual thread prior to heading out.


First time shooting manual lens. Is this pic out of focus or aperture too open? Any advise is welcomed. I just wanted to confirm what I did wrong.

f/1.7 1/125s 50mm

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08-18-2009, 07:53 PM   #2
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Looks to me that your focus point may have been on the background trees. You were using f1.7? Too open for that shot. Probably should have been around f5.6 to f11. Don't rely totally on focus confirmation. It's not all that accurate. Maybe your diopter needs adjustment?

Larry
08-18-2009, 08:02 PM   #3
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I've got a 50mm 1.7, too. I love it, but I had a lot of trouble focusing it for quite a while.

I would get the same thing you did -- a manual focus confirmation from my K100D, and a background in focus, foreground out. I've since gotten a manual focus screen from jinfinance on ebay, and that helped a ton. I'm still not particularly good.
It's hard to tell from the LCD what's in focus. Gotta zoom in all the way and confirm.

At 1.7, the depth of field is very shallow. Works well if you're doing a portrait of a single person standing still, but for a shot like this where there are 3 people and a gate in front, you'll want a much deeper depth of field.
As Larry mentioned, you should choose an aperture setting around 8ish for this shot. Much more forgiving in terms of what you can capture in focus.

-graham
08-18-2009, 08:29 PM   #4
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The viewfinder *will* lie a bit and show more in focus than will really end up in focus in the actual shot. so you have to get used to anticipating. But it won't be off by this much. It's possible your focus screen is installed incorrectly (have you ever removed it?), but just as possible you let yourself be fooled into checking focus by looking at the trees rather than the face, or let yourself be fooled by the focus confirmation beep, which certainly didn't discriminate between face and tree.

08-18-2009, 10:15 PM   #5
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Larry - Before shooting with the manual. I also shot with a 70-300 with auto-focus. Those images came out nice and sharp. So i dont think the diopter is inaccurate.

Graham - Will the manual focus screen work with the focus confirmation tool? Kinda scary thinking I have open-up the camera to install it. Thanks for the suggestion i will look it up further

Marc - I do not think I have ever removed the focus screen. It is possible I was fool by checking focus.

Safe to assume that the equiptment is a-ok and the problem is my skill?
08-18-2009, 11:11 PM   #6
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QuoteOriginally posted by prinze18 Quote
Larry - Before shooting with the manual. I also shot with a 70-300 with auto-focus. Those images came out nice and sharp. So i dont think the diopter is inaccurate.

Graham - Will the manual focus screen work with the focus confirmation tool? Kinda scary thinking I have open-up the camera to install it. Thanks for the suggestion i will look it up further

Marc - I do not think I have ever removed the focus screen. It is possible I was fool by checking focus.

Safe to assume that the equiptment is a-ok and the problem is my skill?
Ummm...the diopter adjust and AF are not related (different light paths). To check the diopter:
  1. Point the camera at a well-lit blank wall
  2. Don't worry about whether the lens is in focus
  3. Adjust the diopter setting until the AF zone lines in the viewfinder appear sharp
  4. If the diopter has inadequate adjustment, there are auxiliary viewfinder attachments that will provide additional +/- bias. My daughter is near-sighted and required a -2 diopter on her K10D in addition to the built-in adjustment.

When doing manual focus:
  • If using focus confirm, be sure you are focusing on your subject and that the green hexagon is lit. I know this sounds silly, but in your example picture focus was attained for the background, not your subjects. This may happen if you are using focus confirm and allow the camera to choose the focus point.
  • Use a narrow enough aperture to insure adequate depth-of-field. Use the DOF preview if in doubt.
  • Be aware that critical focus may be difficult to attain using the stock screen with lenses with maximum aperture wider than about f/3.5

Steve

Last edited by stevebrot; 08-18-2009 at 11:19 PM.
08-19-2009, 08:28 AM   #7
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I would assume the problem was in your technique, but I'd also test that by practicing around the house. Open the aperture to f/1.7, focus carefully on an object, take note of how much appears to be in focus in front and in back of the subject, then takle the picture and see how it compares with your expectations. it's normal that there would be more in focus in the viewfinder than the picture. It's not normal that something would be in focus in the picture that was *not* in focus in the viewfinder. Assuming the practice tells you the camera is fine, then keep practicing and you'll get better and better at it.
08-19-2009, 06:30 PM   #8
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This sounds like great feedback to me.

Thanks a bunches. Back to practise taking picture of a moving snail

08-20-2009, 11:59 AM   #9
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Prinze18: Were you trying to focus on the gentleman with the tripod? It looks like the vegatation to his left is in focus. I you used the center point confirmation it may have given you the beep because it was focused- just not what you had intended. I agree with others that 1.7 is way to wide for this type of shot.

A couple of suggestions:
1. I turn of my LED and audible beep confirmation and allow my eyes to fully concentrate on the point I am focusing on.

2. The other suggestion seems obvious but I practice all the time. Not on serious subjects. I have hundreds of shots of by bathroom! I work on technique with camera holding, body position, and working with narrow depth of field so that it becomes natural. Also, in low light I work on manual focusing. I should not that I have a Katz eye focusing screen. They are pricy but I enjoy using the older manual lenses and working on the art of manual focusing. Certainly not mandatory but very helpful.
08-20-2009, 02:28 PM   #10
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Just look at the whole screen when you focus.
It comes from blurry to becoming sharp but with the stock screen, this is kinda hard to determine but it is noticeable.
You might have been distracted by the whole background being in-focus and the focus confirmation lighting up green ('coz it confirmed focus on the background).
You probably didn't actually check whether the subjects themselves where in focus when you got the green light so you took the shot.
08-20-2009, 02:31 PM   #11
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When I focus manually, I go from blurry focusing screen to being in-focus then past the focus point to blurry again (to confirm that I passed focus) then go back to focus...and then shoot.
I rack up the focusing ring back and forth so i know which point of the turning is actually the focus point. It is more like fine tuning the focus.
08-20-2009, 09:48 PM   #12
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MSM - Indeed I was focusing on the my "assistant" - hihih, It was my first time using a manual focus. Sometime I also switch to manual focus when the AF is hunting too much. Yes I was using center point confirmation. Should I have used another confirmation point?

GerryL - great tip on going beyond and double back on the focus point. I think I may also rushed the shot and being distrated by the bg.
08-20-2009, 10:39 PM   #13
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Center is the only point that works with a manual lens. The issue wasn't which point you used, but the extent to which you relied on confirmation at all rather than your eyes. Confirmation just tells you *something* in the general vicinity of the center is in focus. It can't distinguish between a person and the tree right behind them.
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