wide aperture and low light

I can't post my samples so you'll have to take my word for it that "they stunk".

 

At wedding I assisted last week, I tried something I have tried before (also

without luck which is why I have steered clear of it until now) - shooting with

my 50mm 1.4 during reception without flash. Basically, very occassionally, I got

a neat looking candid of people talking at the tables or whatever. But mostly, I

had trouble with focusing. I'm not sure what my question is because I'm not sure

what the problem is - the wide aperture making the in focus area small and

sensitive, or the low light making it hard to auto focus? or both? and whichever

the problem, what is the solution? Can it be a matter of just practicing to get

the focus right? When I switched back to flash, I was able to focus and still

use wide aperture.

 

I practiced with my dog friday, though it wasn't in low light and he mostly

wasn't moving so not sure how good it was for practice and things came out as I

wanted. (just first group of shots is from friday- up to his wearing glasses)

 

http://www.photo.net/photodb/folder?folder_id=524837

 

I have to stop avoiding this lens and be able to use it. What's the use of 1.4

if I can't use it-

beautiful dog. My little ankle biter wont stay still long enough.

 

A friend called desperatly with gear issues and I rushed to her aid. Loaned her my SB800's and broke out the Leica for fun since I wasn't on the clock.

 

Here was an attempt yesterday from my Leica. Both lense and camera date to 1959, and I think it shows.

 

Can't wait to get back my 90 cron shots with my other M3 body, because I know that one is in better shape.

 

My focusing was pretty good, even with the recession (?) shots.<div></div>

Lauren,

 

When using these wide aperturs, you have to develop good focusing techniques. The best practice is learning how to use your selective focus points while you have the camera to your eye. Learning to use these focus points fluently, will minimize movement and will ensure focus position. The focus/recompose technique is worthless with an apeture of 1.4......simply too little DOF for the slightlest mis-focus position. Also, remember the rules of hand holding sufficient shutter speeds in natural light (shutter must be equal to the focal length) (unless using proper lighting ratios).

Hi Lauren, if I remember correctly you are shooting with the D70. They are not the best at finding focus in low light. Practice manual focusing and using the focused indicator in the bottom left of the display in the viewfinder, then reframe and shoot. I hope that answers your question.

Have you looked at this site yet? http://www.dofmaster.com/dofjs.html

Wide open apertures are tricky and it's good to know exactly what will be in focus at a given aperture and distance. This calculator will show you that if you focus on something 20 feet away with your 50mm lens at f/1.4 on a D70, the area in focus will be 2.75 feet. So for photographing a few people, you'll want to be at least that far away, maybe further. Write down the focus distance at certain f/stops, get familiar with them, and you'll know that lens well.

Can't you switch your flash to some AF assist only mode? - I've seen a few PJs having their flashes riged up at no flash allowed locations.

 

Practicing AF spot selection is a good idea too.

You just found out for yourself that myth of using fast lenses for low light is just that: a

myth.

 

Fast lenses give you a nice bright viewfinder, but that's about it. There are very few good

images to be had at wide open, especially in social events where more often that not you

end up trying to photograph a group of people up close; one person ends up in focus but

the rest are blurred. Sure, you can take a nice portrait that way or snatch a nice candid of

that cute flowergirl, but in most cases the DOF is way too shallow...

 

(as demonstrated above, it also works well enough for a big overview shot where the focus

is on or near infinity; you might just get enough DOF way out there)

 

Practice will help, but at the end of the day, in my opinion, f/1.4 is not that useful.

Try setting the camera to use the center AF area. I think that one is the most sensitive. Then you have to look for something contrasty to focus on. Then practice at home in similar dim light to what you had at the reception.

First be sure your problems aren't due to handholding or motion blur. Rule that out--remember, flash freezes motion so the difference you saw between the no flash and flash shots could have been due to that fact. Once you rule out the two things I mention, decide whether to use the autofocus or use manual focus. As others have said, f1.4 has very little depth of field to use as a margin of error. If you use autofocus, use the center focus point and/or rig up your flash so that you can use the focus assist without the flash firing. I don't know how to do that with the Nikon/SB800. And practicing is good. If you decide to use manual focus, you might want to investigate getting a split prism screen.

Jeff Ascough has used a Leica 50mm Noctilux f/1.0 at weddings with fairly

"decent" results. I use my fast lenses wide open all the time. 85/1.2 @ 1.2 about 90% of

the time, and that has a shallower DOF than a 50/1.4. My favorite lenses for hunting

couples shots at a reception is a 135/2L which I can't remember ever setting beyond f/2.8.

I just don't shoot them from 5 ft away.

 

I don't know about your Camera Lauren, but with Canons, the faster aperture lenses DO

focus quicker and more accurately because the more sensitive AF points are activated ...

where they are not with lenses above f/2.8. So, no matter what aperture you have selected,

all modern lenses stay wide open while focusing, so a faster aperture lens will focus faster,

and in some cases more accurately than slower lenses. On some older AF cameras only the

center focus indicator is the "sensitive" one.

 

Of course IF you need more DOF (whether it's a fast aperture lenses or not), you have to

stop down ... fast lenses aren't glued wide open, they do have other aperture settings to

select when needed ... like when shooting a group. Conversly, a slow lens can never be set

to f/1.4 when you want it.

 

Lauren, there are a number of things that can effect the appearance of being in focus.

 

Distance to subject plays a big part in depth of field even when the lens is set wide open.

The further away you are the more DOF a lens gains. If you start moving closer than DOF

becomes narrower and narrower.

 

Another thing I've seen (and done myself) is get to ambitious with shutter speeds when

using a fast aperture lens. IMO, subject movement spoils the appearence of focus just as

often as shallow DOF.

 

When shooting wide open you have to take all of the above into consideration, AND have

good technique. A solid stance is necessary when shooting close up while wide open.

Subject movement and your movement can combine to throw the focus area out just

enough to soften the eyes for example.

 

Practice is the cure, and learning more about how DOF works with all lenses.

Love DOFmaster and have nearly memorized my fav focal lengths.

 

What BAS says is correct. With a 50mm you have to almost think in terms of a wide angle. My 35mm is easier to use, but the effect is still the same.

 

I used the 35mm a few weeks ago indoors for a reception and unless the subject is isolated (hard to do candidly with a 35) the results aren't that great. You certainly have to pick and choose your angle and subject carefully.

Marc--all you say is true and applicable, but just to point out that the semi-pro models/consumer models don't have quite the agile and sure footed autofocus abilities of the pro models, something that I grapple with all the time on my 20D. Probably the D70 doesn't have quite the same autofocus quickness and reliability as a D200 or D2X. A small difference, but there, nonetheless.

The D70 does not have the best AF in the world. I swear my N90s is faster, the view finder is much better thats for sure. Make sure that your D70 is set to use only the central AF point that way you can choose what will be in focus also make sure that the AF assist lamp is working. Apart from that the D70 is what it is the new D80 is supposed to have the D200 AF and a similar view finder so it could be a good upgrade to the D70 in terms of how it functions. I am so tempted by the D80 myself but most of what I shoot are outside B&G portraits usually with a 50mm 1.8 so the D70 usually does just fine.

The D200 is closer to the Cam1300 (F100/F5/D1X) autofocus capabilities of than I ever expected.

 

Hooked up to my 300AIS the manual rangefinder focus is almost non existent with the D70, but pretty nice with the D200.

 

The D70 is a great little camera and I can handhold it to some pretty slow speeds, but you may be losing something on the AF end of things (shake, AF, DOF). You might try manual focus and test the results.

 

I rarely get anything useful with groups at f/1.4 because of the DOF and movement. But it can be pretty special when you hit it big.

<i>You just found out for yourself that myth of using fast lenses for low light is just that: a myth.</i><p>

 

oh BS. <p>

 

no more a myth than saying a tripod can help to steady a camera or that dragging the shutter can help to reduce dark backgrounds. <p>

 

tools and techniques. nothing more. <p>

 

unrealistic expectations or an inability to master certain tools and techniques does not make their usefullness myth. <p>

 

cheers

Mark, sounds like we are in agreement then; wide open is great for shots where you isolate

people, most often when they are further away - regardless of light levels. But I am willing to

bet you usually have a 24-70/2.8 and flash on a body dangling from your other shoulder for

those up close and personal PJ shots.

 

What I am trying to say is: a fast lens is not a replacement for lack of light; when you need a

certain DOF, you need a certain DOF. While fast lenses shot wide open have their use at a

reception, trying to ditch the flash and simply grabbing a 50/1.4 and opening it wide to get

the same shots just won't work.

There are unlimited numbers of good pictures available at any aperture, including wide aperture.

 

I know it's a simple suggestion, but... have you tried focusing manually? If your camera's viewfinder is too dim for this AND your camera won't autofocus accurately under these conditions, you may have a camera problem rather than a lens or technique problem.

Bob, your first sentence made sense.

 

The second sugests that Lauren's problem is simply one of focussing. As we haven't seen

Lauren's images, who is to say she isn't simply trying to take the kind of images that won't

work at f/1.4? Just because there are unlimitted good images to be had at f/1.4 doesn't mean

any image will work just by focussing right...

Thanks everyone for all the answers. I think I may have some combinations of the mentioned problems and will have to continue practicing to figure it out. I have tried manual focusing but can not be sure I trust my eyes.

 

Someone mentioned recomposing. That is something I've had trouble doing - even if I don't lift my finger, the focus goes out when I go to recompose. and I think some of the problems are due to that and my maybe not noticing every time it happens

Depending on AF for low-light shooting can be dicey depending on the camera you use and how you use it. Manual focusing with some of the lower-end DSLRs is difficult because the finder is smaller and harder to use (AF body screens aren't as easy to focus as older MF viewfinders, for instance). Takes practice and patience.

Lauren--is your camera set to One Shot (it's called something different on the Nikon)? If it is set to Servo, the focus may wander, especially if the subject moves. Anyway, the semi-pro/consumer models have a harder time with this--there is a tendency for the focus to wander even if you set it to One Shot. Got to watch for that. One of the things I hate about my 20D. Another thing is that the focus locks on to something in front of or in back of the intended point because the focus points are actually bigger than what is marked in the viewfinder.

Make sure you don't have your camera set to continuous AF. That could be another problem because as you move the camera it will focus on what ever is in the AF frame. So as you focus everything would be OK but in continuous AF the focus is not locked.

Nadine and Stuart, I will check those settings. Thanks

Fast lenses, long lenses, tripods, fast shutter speeds, slow shutter speeds, low isos, high isos....... are tools.

<p>

<i>fast lenses and shallow DOF are useful for a particular kind of image</i><p>

 

photography is a wonderful series of technical compromises. I think they teach that in the photography 101 class, right after they teach you what the aperture does. So yes, a shallow dof can be a useful tool, or it can be the compromise you have to work around. <p>

 

be aware of your actual dof, don't just know that its "small" or "large" but exactly where it is. <p>

 

compose first, focus last<p>

 

be aware of the quality of the available light, not just the quantity.<p>

 

if your equipment is not suited for low light work change your equipment. saying that f/1.4 isn't useful because it's hard to focus on a low end dslr is like saying on camera flash isn't useful because the flashcubes on your sx-70 won't lightup a large group shot. <p>

 

cheers

Lauren,

 

 

I found that my 50 1.4 got foggy wide open. Yours may differ but I never went below f2 with it after that.

 

The Nikon lenses that don't fog that low are the 35 1.4 manual and the 50 1.2 manual. I've never tried the 85 1.4 auto so it may be OK.

 

I got both lenses off of ebay and once shot an entire reception with the 35. The trick is to get a split-image focusing screen. I got mine from Katz-eye and I added on a magnifying eyepiece. With it I can focus at 1.4 but only if nothing is moving.

 

These days I generally use my 35 2.0 auto at weddings and keep the manuals for portrait work.