Low light focus performance

[elliot1]

<p>Although your question has really been answered, I wanted to make sure you understood that NO camera will focus in the dark or near dark, including the D3, under the shooting conditions you had, without focus assist.</p>

<p>FWIW, Nikon cameras do not have focus assist either when continuous focus is selected and, depending on the camera, when spot metering is selected.</p>

[bob_osullivan]

<p>I'd just like to ad that if you use any metering mode other than M and use only the ST-E2 for AF assist, then your shots will be under esxposed. In any other mode the camera expects there is a flash that will fire and illuminate the scene. So, only use M with an ST-E2 alone for AF Assist. </p>

<p>I however find that this technique only improves the situation marginally. When it's that dark I'll either use Manaual focus flash.</p>

<p>You could have used flash with it's af pre-flash and set the flash to Manaual at it's very lowest settings to preserve the natural light mood and dragged the shutter. Of course oneshot and center af point still apply.</p>

[picturesque]

<p>Michael--I don't think I need to own a 1DMkIII to know that without One Shot, the focus assist doesn't work. Without focus assist, autofocusing in the dark or near dark is not going to work well.</p>

<p>I shoot weddings and at receptions, nobody reacts to the focus assist pattern at all. Certainly not for subject aware images and even for subject unaware images... During a ceremony, I would not use focus assist, but otherwise, it really doesn't matter.</p>

[juans eye]

<p>Youre getting good advice on here. You need to adapt to the situation. I am trying to do a series on hollyweird night life using available light. My little EF 28 f1.8 does ok in extremely dark situations. But I do lose quite a few shots. It is to be expected. I would say that with a focus assist light, you should get back into your regular keeper ratio.<br>

Here is a sample. The two over exposed candles on the bar will give you an idea of how low the light level was. The grain was added with PS. I like the aesthetic of grainy low light pics.<br>

<img src="http://i12.photobucket.com/albums/a218/bing123/MissJuli.jpg" alt="" width="533" height="800" /></p>

 

[david_amberson1]

<p>For sure. A little outide advice and suddenly I knew what I had done wrong. I'm telling you...its a bad feeling when you come to the conclusion that its your equipment and its time to change Manufacturer. It sucks. How am I gonna do it $$$?</p>

<p>As stated above. It was absolutley about..."Do I have the best equipment I can find to make sure my customers are getting good stuff. I absolutley cant afford to start losing this count of shots. Good thing is that it was my fault....for now. I never had this kind of failure in low light before so it freaked me out. Course never this bad. It was similar to the above. So I decided to ask for advice from those who shoot the above.</p>

<p>If I run into it next time after making some adjustments, then I'll do some looking. I was ready to rent a D3 system and go back to see if I would have better luck.</p>

<p>I tested a D3 a while back and I didnt like the slower speed in which it focused compared to mine. I noticed just before it locked, it would ratchet 2-3 times like it wasnt sure, where mine locked with a beep the first time. And it was faster to get there. But yesterday, I started wondering if maybe the 2-3 time double check on focus confirmation would be better all be it slower than a fast OOF. Feel me. All the speed in the world is no good if its OOF.</p>

<p>I'm good for now. Thanks everyone.</p>

<p>Oh, something else. This just put the icing on the cake. After playing with the 50 1.8 today. I noticed it was set to -20 micro adjustment in the body. Just some quick news paper shots set that way compared to 0 was way off. I dont how it got set that way, but it could have performed better Friday night than it already did had that been right. I mean, I know how it got that way. I set it there....obviously. I guess when I made the change back to 0 during setup, I never confirmed it so it went back to -20. AHHHH!</p>

<p>I've gotten to where when setting up a new lens in the body micro adj, I dont do a chart at a 45* angle. It is highly dependent on exactly where the point is. SO I put a paper on the wall with very fine detail. I set the camera on a tripod exactly 90* from the paper. Rack the lens OOF, then let the camera focus and check it @100%. I set the micro adj. to whatever number gives the best detail. I find this represents more of an in field shot of someones eyes than the traditional way. It also worth mention that all my lenses are set to 0. Even the long accused 24-70 f2.8L. It works fine at default. I guess the out of spec is really a rarity.</p>

<p>While I had it out, I decided to do something I've never done. With the 24-70 f2.8L at 50mm wide open, it is just as sharp, maybe sharper than the 50 f1.8 stopped down to f2.8. Surprised me of how well a zoom performed wide open. Maybe all of us should lighten up on our gear a little.</p>

<p> </p>

[sofie_dittmann]

<p>I admit I didn't read the whole thread, so some of this may be repetition. Your camera will always have issues focussing properly in low-light conditions. Once it does focus, it'll try to readjust once you hit the shutter. It's just the nature of the beast. Nothing wrong with the camera.</p>

<p>Last time I took pictures in conditions like that, I used the highest ISO I could live with with the smallest aperture it would take. I agree with one of the posts above that grainy photographs like that have their own charm. Nothing wrong with that. And once I focused, I switched AF off in order to prevent the camera from readjusting itself. B/c it will do that.</p>

<p>So, bottom line: keep your camera... or give it to me! :op</p>

[catchlight]

<p>I don't think anyone has mentioned "back-focusing", a technique often used for shooting sports and other fast action.<br>

With single-point, centre-focus it can be very useful in locking focus in low light, especially when working without flash.<br>

Use Custom Function 4 to move control of autofocus to the * button, just behind the shutter. Your thumb can stay on that button, and capture focus before each shot. The metering function stays on the shutter button.<br>

Often you will capture focus on the face or other subject that you want, then recompose the shot. When you fire the shutter, the camera does not re-focus.<br>

It takes a bit of practice, especially so you remember where AF is activated, but in my experience this technique results in a higher ratio of keepers.</p>

[sarah_fox]

<p>Yeah, I was just going to suggest what Brent did. It's a bit of a learning curve, but it's the way to go when your focus is unsure. Do a one-shot focus with the appropriate back button (e.g. *), and after you have your focus confirmed, take a few shots. If the subject distance changes, refocus. Of course if you use this method, you can't use razor-thin DoF, or your focus will still be hit and miss.</p>

<p>When you start doing this, you're going to have a few "D'oh!" moments when you can't figure out why your lens won't focus (when you're trying to do it with a half-press of the shutter button)! ;-)</p>

[david_amberson1]

<p>I'll never understand why anyone thinks that using the rear AF On button focuses differently or better than a 1/2 pressed shutter button.</p>

<p>ITS the same thing. These are 2 methods that do the exact same thing. Its a preference to focusing but will not have any impact what so ever on focus accuracy, speed, consistency.</p>

<p>When I focus, I half press the button and hold it. I can take the picture but not completely releasing the shutter. I release it back to the half pressed position. So the focus will not reactivate or unlock.</p>

<p>I personally dont like having to use my thumb to focus and my finger to trip the shutter. Its not needed to use 2 fingers to do what can be done with one. This allows me to use my thumb in helping stabilize the body instead of pressing another button.</p>

<p>Its there for the people who cannot track focus using just the shutter button. They always release it too far causing the AF to stop and need to be reactivated again. I dont have that problem. This is not a work around to achieve a better keeper ratio, unless you cant do as I described above.</p>

<p>Brent you are describing it as if you hold it down all night. And you mention capturing focus before taking the shot. I always "try" to capture focus before each shot. I never just raise and take a picture and hope for the best. I notice some people like to just full press the shutter button so that when the camera sees focus it fires automatically. This is not the correct way to operate the camera. Me raising my camera, half pressing the shutter button to focus and wait for lock/confirmation then hold it. Then I recompose and trip shutter only releasing back to half pressed position if another shot is in the works. It does the exact same thing if you raise the camera then press the AF On button to focus. Also you are describing it as if the camera refocuses moments before the shutter it tripped. As long as you lock focus and hold and never release, it does not refocus at all.</p>

[alan_bryant1]

<p><em>ITS the same thing. These are 2 methods that do the exact same thing.</em></p>

<p>No they don't, at least on my 5D they don't. When you use the two-button configuration, the camera will always take a picture when you press the shutter button. When focus and shutter are tied to the same button, the camera will refuse to shoot unless it believes it is in focus.</p>

<p>That's a huge difference in low light when the camera is never really sure about focus. Basically it refuses to work at all, even when it is in focus, it can't be sure of that, so it won't take pictures. It's completely infuriating, and the only cure I know of is to use CF4 option 1.</p>

<p>Maybe the 1D series works differently; I've never used one.</p>

[catchlight]

<p>David, I fully respect your experience and the techniques that work for you, and was just suggesting that "back-focus" might be worth a try for the situations you described in your original post.</p>

<p>I began using the technique when shooting ski racing and other sports in AI Servo mode when you do, indeed, lock focus on your subject and hold the * button down while capturing a short burst of shots. It is standard practice among sports and wildlife shooters.</p>

<p>I liked the advantages of separating AF from light reading/shutter activation so much that I now use it in other situations, including low light settings for concerts and theatre. With these more static subjects, I place the centre point on my subject, hit the * button once, recompose, and shoot.</p>

<p>I've also used the technique for wedding ceremonies and receptions in dark venues, with good results. </p>

[juans eye]

<p>David,<br>

I think you should really try the back focus button. There are great advantages to seperating AF and Exposure, especially in difficult low light situations with intense light sources mixed in. AND, this addresses you preference for using AI SERVO.<br>

Think of it, besides the camera focus confirm override that a few had mentioned, (in difficult/moving low light situations) you can lock exposure while using spot meter and continuously track the subject and activate the AF when you are ready to take the shot.</p>

[david_amberson1]

<p><strong>>>Alan</strong>. The 1D is different. It can be set to take a picture even if not confirmed focus. Its for those times where it doesnt matter and you want to gamble in hopes of just maybe getting the shot.</p>

<p>Mine is set for focus confirmation. I didnt have an issue with no focus. My issue was with using AI Servo which was stupid on my part for the enviornment because I was using a 2.8 lens and no focus assist in such low light with AI Servo on a static subject. It was definitley 1.8 light for sure. I was asking for trouble. And if it havent been for the amazing machine as the 1D3, I wouldnt have got a 200 out of 279 keeper rate. I'm lucky I got that. And actually, about 20 of those tossed were because I didnt like the shot. Not OOF. More on that in a minute.</p>

<p><strong>>>Brent</strong>. I'll try anything once. If it works for you guys, then thats all that matters. Inever could see any benefit, so I dont use it. But I'll try it some more for sure. If it works out for me, I'll let you know.</p>

<p>To elaborate more on the focus issue. I played some more tonight, dialing back in my 50 1.8 and double checking the 24-70 I found some more micro settings out of wack. I think the last test session I did with setting my Micro adjustments, I may not have confirmed my adjustment causing it to revert back to the +/- settings I had before. All my L Series lenses are good at 0. The 50 1.8 worked best at +8. I then went to my hallway where I have a dredded paint run on a the wall. Very dark and no light, I couldnt even see the run on the wall through the viewfinder. Without focus assist, just hunting. With the flash on, both lenses nailed perfect focus everytime almost instantly in a hallway with no light at all.</p>

<p>And think, I tried to shoot all night with a 2.8 lens...in AI Servo....no focus assist. I am so lucky I came home with any usable images. God bless the 1D3.</p>

<p>Everything is golden now. I can go to the dark corner of my hall and at a 45* angle to the wall and nail the focus dead center on a paint run in total darkness that I cant even see in the VF. Thats one hell of an AF.</p>

<p>Now, wonder if I can get everyone to rerun this party again so I can have another go at it. Comforting to know now that the next job I have, everything is in order.</p>

<p>Thanks everyone.</p>

[madza_zulu]

<p>Will this help ? :-)<br>

http://photography-on-the.net/forum/showthread.php?t=28314<br>

<strong><br /> </strong></p>

[lee_smith2]

<p>Hi David, I feel your pain, Why weren't you shooting at 3200ISO, that might have helped your AF problem also. I don't think you were really using the low light capabilities of the Mark III. Lee Smith</p>

[david_amberson1]

<p>Well, shooting at ISO 3200 would do nothing for AF issues. It doesnt effect how the camera focuses at all. But it would allow more light to be recorded and ISO 1600 gave me enough ambient light without increasing noise using ISO 3200.</p>

<p>Yes 3200 is good, but 1600 is even better. I could have went ISO3200, and stopped down to f4 maybe, but found f2.8 to be enough DOF is most cases. I was shooting in the 35mm-50mm range all night from 10 feet or so. Subjects on the same plain. At these shooting specs, DOF wasnt an issue. Although I do wish I had for one or two shots, just didnt think about it before hand.</p>

[alec_myers]

<p>I've done a lot of low-light photography in clubs - literally tens of thousands of shots. And most of that done without focus assist, because the subjects are dancing and need servo focus. Just to address the other stuff on the o/p:<br>

"I'm thinking a 50 1.4 last night and I would have been golden." Be careful; it's easy to end up with a DOF so shallow that the right eye of the subject is in focus and the left eye is way off. Or, if you're not spot on with where you aim the focus box, the tip of someone's nose is sharp, but not the rest of their face.<br>

"Maybe even a 24 1.4L." - at 24mm, DOF with f/1.4 is more plausibly useful in most situations.</p>

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