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Blurry/Out of focus Pics
I am editing a shoot right now and i have noticed i have a lot of out of focus shots. The camera seemed to be locking the focus. I didn't have n cont. mode. The shots looked sharp in the view finder. What could be the problem? Equipment - Nikon D200, Sigma EX 28-70 2.8 Jun 23 08 01:46 pm Link Side note I was not to close for the lens to focus. Jun 23 08 01:48 pm Link you're going to have to post some examples...you haven't given enough information. What was the lighting like.. what settings etc Jun 23 08 01:48 pm Link FlirtynFun Photography wrote: Plenty of natural light, Iso 400, aperture 2.8, shutter speed 160. Jun 23 08 01:55 pm Link Backlighting involved? Jun 23 08 01:58 pm Link Simplesoul26 wrote: No it was a basic shot. Nothing fancy. Jun 23 08 02:02 pm Link D-200 at iso400 has a lot of noise to begin with. Combine it with an aperature at 2.8, and you wont have the most sharp, crisp image. this is only my initial thinking without seeing the image. Jun 23 08 02:06 pm Link are you use to using 2.8? Might be more "soft" than out of focus?? Jun 23 08 02:07 pm Link Maybe you had the wrong focus point activated? Maybe the lens was in manual focus mode? Maybe the camera is malfunctioning? Maybe the lens is malfunctioning? Who knows..... I doubt we will be able to diagnose it remotely, even if you do give us more info. If some are sharp and others are not is likely a focus point issue. Jun 23 08 02:08 pm Link Sigma lens..you have to be meticulous about your AF. Make sure you know where your AF point(s) is/are. And I program my cam with a hot button for focus. lets you make SURE you're sharp before you click. that 'half push' is just a bad idea, IMO. You're wide open so it's very unforgiving. And make sure you're holding the cam still...if you're zoomed way in at 160 you could be getting some cam movement that's so slight it looks like OOF. I think if you bought some better glass you'd see a WORLD of improvement in this. My Tamron did the same thing. It holds down my bills on my desk now.  B Jun 23 08 02:09 pm Link Edited: Actually Sigma lenses can be a bit soft wide open, especially on the far ends of their zoom range. Jun 23 08 02:09 pm Link Leroy Dickson wrote: Read the OP before asking questions that are answered in the post. Jun 23 08 02:10 pm Link Studio 68 wrote: some lenses when you shoot wide open your not going to get as sharp as possible with the lens, its a good idea to close it up a stop or so, thats when youll get the sharpest glass. Jun 23 08 02:11 pm Link Chris Macan wrote: Yeah, I skimmed over that.. edited post. Jun 23 08 02:12 pm Link Is the background in focus? Jun 23 08 02:12 pm Link Leroy Dickson wrote: I've done the same thing more times that I like to remember. Jun 23 08 02:13 pm Link Taking the above posts, I would agree that at f2.8 the lens will be rather softer than stopped down to say f4, this seems true of Sigma lenses and I suffer the same with a 70-200mm model, but to suggest that the D200 would produce a noisy image at iso400 is off the mark I think, I never worry about taking the iso upto 800 and even higher if I plan to run a noise filter over the image in post. Is the lens quite new for you? If so, then quite likely you have not until now had a chance to use it in anger at f2.8, I always have to stop down at least 2/3 to f3.5, also if using at maximum reach I always need to wind back a few mm to get things sharp. Jun 23 08 02:14 pm Link martinimages wrote: Might be time for a new lens. Jun 23 08 02:15 pm Link Studio 68 wrote: Until then... try not to bump all the way up to either end of the zoom. Always back off a bit, if you hit the wide or long end and try not to shoot below f/4. Jun 23 08 02:20 pm Link Might be time for a new lens. The EX lenses are Sigmas top models, which you'll already know I'm sure, I would make very sure that the benefits of Nikon glass outweigh the extra cost before consigning the Sigma to the scrapyard! Jun 23 08 02:20 pm Link Before you blame your equipment and start buying new stuff, just post an image showing what you're experiencing. It may not be the lens. To be honest, as with most image problems, it's probably technique. Jun 23 08 02:37 pm Link This is how that whole look started in the 80s. New York big name photog had the same problem, bunch of unfocused shots and they said go with it and they sold the look . The rest is history. Jun 23 08 05:12 pm Link It could be anyone of the things already mentioned. I did have one other incident with out of focus images not having anything to do with technique, apeture, or brand of lens. I bumped my lens and one of the elements shifted slightly which produced out of focus images time after time even when they looked ok in the viewfinder. Got a new lens and everything was ok. Jun 23 08 05:13 pm Link Studio 68 wrote: Ancient Chinese saying: "A photo is worth a thousand words." Jun 23 08 05:16 pm Link Build an optical bench with a ruler, some match books, a try pod and a shutter release. Shoot it all different ways, then look at exif. If ya don't find the problem...then its you Jun 23 08 05:23 pm Link Could be the camera locking focus on the wrong things. My 5D always locks on the boobs, not the eyes. Jun 23 08 05:26 pm Link What is in focus in the photo...if anything? Jun 23 08 05:27 pm Link I used a focal length of 50mm Subject distance 5 ft Depth of field Near limit 4.84 ft Far limit 5.17 ft Total 0.33 ft In front of subject 0.16 ft (48%) Behind subject 0.17 ft (52%) Hyperfocal distance 145.2 ft Circle of confusion 0.02 mm ************************** focal length 70mm Subject distance 5 ft Depth of field Near limit 4.92 ft Far limit 5.09 ft Total 0.17 ft In front of subject 0.08 ft (49%) Behind subject 0.09 ft (51%) Hyperfocal distance 284.4 ft Circle of confusion 0.02 mm Jun 23 08 05:37 pm Link |
