I shot a wedding today and upon review found WAY too many non-keepers due to OOF. f2.8 is not entirely to blame; but even f5.6 or so would have saved me on most.

I used f2.8 for the ceremony and they were fine (lots of distance). However; the hotel room bridals struggled (focus kept getting grabbed by the boquet).

I'm curious; how often do you use f2.8? Often? Only when absolutely necessary?

So; the obvious question is; what's your go-to f-stop for:

1. Making the rounds at the tables?

2. Fairly well lit church that frowns on overuse of flash?

3. Group shots?

4. Dancing (night or indoor)?

Obviously; "it depends". But in general, I'm curious what how it usually ends up.

I use f/2.8 a LOT. I really don't have problems getting a good focus though, is your lens back-focusing?

Leann

Are you using all the focus points...or just the centre point? Centre point only is best when using shallow DOF.

Something else that's helped me get better focus is using the 'back button' to focus. There's been quite a bit of discussion on this...I'll try and find it for you.

HERE 'TIS

There are more threads on this...just try a search on 'back button'

Hope this helps....

Oh, and if you're already doing both the things I just suggested, please ignore this! LOL

Annie

I use f2.8 ALL the time. This weekend I rented a Canon 50mm f1.0 (they haven't made it for like 20 years), and that lens was gnarly! I'll post some shots later on my blog at f1. It's pretty nuts, but worked really well.

Considering I use my 70-200 2.8 outdoors, I keep it at 2.8 (3.2 for a larger group). I love shooting wide. I don't really have OOF shots outside of the occasional few from movements/camera shake, etc.

Keep trying!!!

Sounds to me like you are having focusing troubles not f-stop troubles. I shoot at 2.8 all day long with the exception of the group shots. I think the first post got it right, the key is to use the center focus sensor. Focus on the eyes by pushing the button half way then re-compose and push the other half. I my experience the camera dose a poor job of deciding what you want in focus. "Focus and re-compose"

Carl Stevens
www.artists-eyes.com

I always (well, not always, always) use 2.8! I love shallow DOF and I must say I think I'm addicted to shooting wide open. Keep practicing. Could your OOF shots be camera shake or something?? I have to really concentrate on breathing right sometimes so that I'm not wiggling. What lens are you using??

i dunno what make camera you are using, but the more expensive models D2x, MKIIn have more focus points stronger focusing motors (more power) and better focusing algorithms.

I rarely use 2.8. Over 80% of my images are shot at 1.8 or 2.0.

Karen

I'm with you - I use 2.8 when that's the best my lens will do. I love 1.8 and 1.4 and I wish even more that I could get loving on a few 1.8 lenses in the coming year.

I love shallow and dont have too many focus issues with it. have you tested the lens?

sounds to me, as others have said, that this is a problem more with your focus point selection than your aperature. i would highly recommend not letting the camera choose your autofocus point, especially at 2.8.

i shoot at 2.8 all day long, but im always changing my autofocus point around throughout the day, always. it's constantly changing for me. i do realize there are 45 points on the 1D so it makes it easier than maybe the 5D or 30D, but even those have enough points to make the switching easier.

try moving your points around to ensure the right portion of your image is in focus. even if you just went to 5.6 in the shots you described the focus would be on the bouquet, not the bride. so while she might be acceptably in focus, it's not how you want to shoot.

PS - guys...it's not the lens. she even said "the camera kept picking up the bouquet." that lens can obviously focus right.

i shoot wide open all the time too. can you post up some example OOF shots? it's better to get the focus on the right spot rather than rely on larger DOF from stopping down. another thing that could cause OOF shots wide open is focus and recomposing.

having said all that, it's possible that the camera or the lens could be the culprit. one of my 20Ds had to go into the shop because it was back focussing. in your case, it is possible that either your camera or lens could be front focussing, which is less common but highly possible.

She probably noticed this after the fact, and front/back focusing issues do exist. So, it could be the lens or camera. But most likely, it's the technique.

I did not know there was another setting besides 2.8. Just kidding. I am always set a 2.8 or 1.4 on my 50mm. Always worth the cost because your glass is where it is at.

Hi Leann,

I've heard this term thrown around but unfortunately I don't know what it means. What is "backfocusing?"

one way to find out is to follow the instructions on this site:

http://photo.net/learn/focustest/

Thanks for all the responses. I didn't elaborate much for sake of brevity.

I shot the 17-55 IS + 30D using center focus point and my habit is to half-press the shutter button until I see the red blink, sometimes I re-center. I habitually focus on eye slits then re-center, but I'm guessing I just got slopy.

Thanks for the back-button tip. I keep the * for the test flash strobe, but I think programming another button for that is possible.

Agreed; "the camera kept picking up the bouquet" is operator error. It was a poor example since I do that intentionally sometimes (although usually at f1.4 since f2.8 isn't dramatic enough) and maybe I just over-used it.

That camera is fresh back from Canon for focus issues so it may be inconsistant, but whether Operator Error or Equipment, I really need to get this sorted out quick. I only recently switched to a f2.8 zoom and haven't had focus issues previously (some slow SS blur on occassion, but not missed focus - I had noticed that previously and switched bodies immediately).

However; my question is answered. You guys do it all the time, so I just need to practice more, resolve my issue, whatever. The answer is not "hey, most people stick to f5.6 for this, f8 for that, f4 for other stuff, and only f2.8 and below for a few artsy shots".

80%, at 2.0 or under, wow! I also like bokeh but my percentages go way down when doing it on the run.

Bottom line; I either got spoiled with my f4 IS zoom and haven't done enough prime work lately, or the camera's inconsistant. I'll do some testing. I'm realizing that it works well in good lighting, but dim stuff is less. I'm really envious of the AF system on the 1D series. Some day...

I shoot as wide-open as possible. I have a 50/1 for my Leica M8. That is my favorite lens. Even stuff 20 feet away has selective focus.

For SLRs, I'd put the focus point only on the center, ever, ever, unless you're focus tracking on something in motion, and then select an off-center focus point.

Also, one shot autofocus mode helps improve focus accuracy.

Also, lenses faster than 2.8 have greater focusing accuracy. When the camera is not taking a picture (e.g. when it's autofocusing) the aperture is as wide open as it can get. When you're shooting with an f/1.4 lens (for example) the camera has 2 more stops (4x as much light) to "see" what to focus on. So I find that my 24-70/2.8 focus-tracks more than my 50/1.4.

But if you want hyper-accurate low-light focusing, even wide open, buy a Leica M8.

I'm also a wide-open shooter - the key is knowing how much depth of field is possible based on your distance to the subject and the lens length. For example... at 24mm @ f2.8 is going to have a much larger depth of field than 50mm @ f2.8 from the same distance. Step back a few feet and you get a larger depth of field, get closer and you have a shorter depth of field. When you're taking portraits and you're close enough to be in the range where you only have a few inches of DoF than you need to consider with AF point will give you the most accurate sharpness instead of focusing & recomposing, which changes the plane of focus. (does that all sound like mumbo jumbo, or what?!)

Basically... once you know how much DoF you have at any given distance with your lens of choice, you can make better decisions about how wide or tight your aperture needs to be to give you the field of focus that you're looking for.



Hmmm... do you shoot in a way that lets the camera select your AF point, or are you manually selecting where it focuses? That could be the cause of great distress!! Another tip for faster focusing is to find a point of contrast - which is what the lens needs in order for it to focus - so putting your focus point on a white dress or black tux is useless to the camera, but focusing on the point where the tux meets the white shirt is very helpful!

To answer your original questions...
I'm curious; how often do you use f2.8? Often? Only when absolutely necessary?
VERY often.

So; the obvious question is; what's your go-to f-stop for:

1. Making the rounds at the tables? f2.8 @ 24-35 mm from about 6 ft. away.

2. Fairly well lit church that frowns on overuse of flash? f2.8 for most everything because I can be far enough away at all times. If I'm in a situation where I have to prefocus manually because it's soooo dark, than I'll usually bump it up for more breathing room and pop some flash in the scene.. ie. processionals.

3. Group shots? For formals, I usually bring it up to somewhere between 4.0 & 5.6 depending on the focal length and distance to the group. Always keeping in mind - 1/3 in front and 2/3 in back is in focus.

4. Dancing (night or indoor)? f2.8 or less!! Unless I'm doing some really cool light painting or dragging shutter effects.

Right on!

So you focus, recompose, then shoot? I just can't use that technique! I always change focus points in order to change my composition. It's not so bad when your subjects aren't moving, but I find that mine are always in motion, pretty much. Even with posed shots or when people are sitting down they still move enough to ruin a shot with shallow DOF, because they may throw their head back to laugh or something like that.

By the way, I have far, far more keepers with this technique when using my D2X copmared with my 5D. The focus is just so much faster and more accurate, especially in the non-centre focus points (and particularly with lenses that won't go as wide as f2.8).

Oh, and I should add that I always use the continuous (AI) focus for moving subjects, even if they're not moving much.

I don't know the D2X or the 5D, but with both my D70 and D200 doing this will be much slower than using the center focus point, pressing the shutter 1/2 way, recomposing and shooting. Since I have gotten used to it, I am pretty fast. As for moving subjects, unless they are moving away/towards you then you can't use the focus, recompose, and shoot, 'cuz they'll be blurry, so in this case set your camera to continuous focus and focus with whatever focus point falls on your subject with the composition you want.



I think this could be a cause for your OOF problems. In this setting the camera will take the picture even when it's not in focus and if you set your subject on a focus point and then even slightly move your camera, your hand, your head, etc. your point of focus would have changed.

The only time I get some OOF shots, is when shooting with my 50 f1.8 @ 1.8 and up close and that is mostly because either the subject or I moved.

Hope this helps.

Thanks Anne:
To answer your question - I always (with a very rare exception, like once a month) use the center AF button and recenter. However; last month I caught myself not paying attention to the little "focus locked" light in my viewfinder. I do wait for the beep and I think it's the same thing, but that could explain my results. Also; with only a few inches to play with, recentering can also be an issue.

Andrew:
Thanks for the tip on wider lenses. It never occurred to me that more light would improve AF accuracy - drrrr, that's so simple! My subject had bright backlighting (I always shoot in Manual exposure mode) and I'm wondering if that affected AF at all ... that is, focusing on the darker face. Is that a factor?

Also; my brain just tweeked that I used the edge of her face outline on a few shots and, ummm, it undoubtedly grabbed the curtains behind her.

Hey; I did get about 5 or 6 very acceptable shots from the session so it wasn't a failure. It just got me wondering if I was being stupid in trying to do it all wide open - since backing to f5.6 or above would have been so much safer. (True; it wouldn't solve actual errors and Andrew; it may have even introduced more AF errors due to smaller aperture).

I believe that putting a 50 or 35 prime on and backing up to the other side of the bed, and maybe even breaking out a monopod, is what I'll try next time I'm in that situation. I've almost exclusively used my 35L and 85 f1.8 when shooting prime, for many obvious reasons, but a big one is that I've not had focusing issues (I usually shoot them at f1.6 and 1.8 respectively). Your explanation would explain, I suppose, why I find them such good focusing lenses.

Another thing about f1.8. Here's a portrait the couple chose (different couple) taken with my 85 f1.8 + 30D. She's nicely in focus. His head is just about 2 or 3 inches forward. Maybe the focus point is back an inch or two because of the focus-recenter (actually; I think I keyed on her locket).

I just have to say; I don't know how you guys do it. This photo is reasonably sharp but they want a 12x18. With such tight tolerances, oh my gosh how can they all be perfect? f2.4 even would have expanded my DOF a lot. I know; a seasoned pro would have known it's only a 1 inch DOF and wouldn't have shot that - focused on him since he's slightly in front.

Their number 2, 3, and 4 choices were good so I'm covered, but it's just a thin line.

Thanks for the tips, Ramiro. I think part of the reason why the D2X will get more in-focus shots than the 5D is because the D2X won't fire unless the subject is in focus, but the Canon does.

I used to do the focus-recompose-shoot thing--I started into the SLR world with a Pentax K1000--but I found that it wasn't a good way to capture fast-moving subjects, so I haven't done it for a while. You're fast at what you do because you've practiced it; I'm reasonably fast at switcing focus points because I've practiced that.

I do family shoots where I almost fill the frame with a small child running around the house or yard. Would you be able to use your technique in those situations? If you really think you could then I might practice your method again to see how I go.

Cheers,
Mark

While I do like shots wide open, I really love to crank the aperture to f18 or f20 and shoot that way. Everything looks surreal and the complexity you get in background with everything in focus can really make a composition pop...

It really just depends on the way you like to shoot. I love the almost plastic look of really high apertures but the bokeh of an 85 set at 1.2 is pretty amazing too. If you shoot wide open just make sure you take lots of frames and try not to focus and recompose too much as the focus point will be thrown off.

ken