Focus precision, 20D vs. XT. Technique etc.
I have deficulties shooting fast moving objects like my toddlers, indoor with large apture with my Rebel XT, say on f/2.8. I tryied One-Shot, Al-Servo. Single point focus, multi-point focus (automatic??). Anyway the keepers rate is kinda low, say arround 50% or less. Stop down to f5 and below really helps. But I think it is not I focus better, but the DOF saves me.
I tried my brother-inlaw's 20D few times and I got more keepers. It looks like to me the 20D is faster and has better focus presicion. Is this actually true? Anyway, I know my technique sucks as with XT I can shoot stationaly objects fine but not fast moving toddlers. Everytime I stick a lens in front of their faces, they tend to chase me down and grab my camera. I can hardly get a focus, not to mention compose the picture. I would like to hear your tips on fast presicion focus and technique shooting picture in this kind of situation.
Thanks :thumb
Eric
I tried my brother-inlaw's 20D few times and I got more keepers. It looks like to me the 20D is faster and has better focus presicion. Is this actually true? Anyway, I know my technique sucks as with XT I can shoot stationaly objects fine but not fast moving toddlers. Everytime I stick a lens in front of their faces, they tend to chase me down and grab my camera. I can hardly get a focus, not to mention compose the picture. I would like to hear your tips on fast presicion focus and technique shooting picture in this kind of situation.
Thanks :thumb
Eric
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You may not want to hear this, but I think, even with a 20D, you're going to have a real hard time shooting kids in low light. I recommend you give strong consideration to an external flash. I know I will be when the kids come around, even though I love to use my fast lenses.
www.ackersphotography.com
http://www.chrislaudermilkphoto.com/
Thanks Ben!. I am currently using a 430EX bounce agaist the ceiling either to my left or right. I manually set F/5 and 1/100s or so with about 100mm focal length and so far this gives me the best result in terms of getting it sharp in focus.
Eric
We need more information. Different lenses have different properties, we need to know which lens you are referring to.
What is the ambient light level? (Exposure settings without flash.)
Is the focus assist lamp coming on, on the 430EX flash?
You have also commented on noticing that increased DOF gets more keepers. That's a good thing (more keepers) and a valid technique. Most lenses actually have their greatest sharpness at middle apertures as well, so maybe you could use the technique of more DOF more often? (Unless shallow DOF is important to the shot as in background control.)
Later,
ziggy53
Moderator of the Cameras and Accessories forums
At the beginning, I took a lot of pictures with a 24-70L without flash, mainly in the family room with daylights from windows or in my daughter's bed room with 2 energy saving lights equivalent to 150W normal light bulb. Family room is about 22x20 square footage with big windows on three sides of walls and relatively bright. If I shoot wide open at f2.8 apeture priority and bump the ISO to 400/800 (Depends on the time of the day and weather) I can get anyway between 1/30" to 1/60" so I can barely do the hand held. Again I can shoot stationary object fine with hand held zoom to 70mm. It is reasonably sharp at 100%. I have no tripod, but if I put the camera on a table and use the selftimer it will be of course even sharper. But in my daughter's bed room, the speed goes done to 1/10" or even lower with ISO 800. I never had any success with handheld. But again I never tried below 50mm. Either case, I never noticed the focus assistance lights lit on the flash.
Recently I start to shoot with 430EX bounce of the ceiling and find that I am more successful with a 70-200L F4. I usually set apture f5 to f5.6 at 1/100" to 1/125" manually and use ETTL. The reason, that I use the 70-200 is because I can keep more distance from my kids and get less attention. I usually zoom to 100-135mm.
Originally I suspect lens problem, but I was wrong. Both lenses are sharp as swiss knife when I shoot outdoor with sufficient light or in door with flash.
So my objects are to find
1) The better focus technique to shoot fast moving kids indoor (and outdoor). Focus quickly and precisely.
2) Good technique of shooting fast lens wide open. Right now I cannot even handle f2.8. :uhoh
Thanks for the help!
Eric
af is always going to be slow in dim light-try manually focussing
pre-focus to where the kids are moving to
or raise the light levels...
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Canon 20d,EFS-60mm Macro,Canon 85mm/1.8. Pentax Spotmatic SP,Pentax Super Takumars 50/1.4 &135/3.5,Pentax Super-Multi-Coated Takumars 200/4 ,300/4,400/5.6,Sigma 600/8.
A few other points.
Both of these lenses, the 24-70mm, f2.8L, and the 70-200mm, f4L, are pretty fast to focus, so that part of the equipment is about as good as it gets.
When you use the 24-70mm lens, your distance with respect to the subject is much less and the closing "rate" of the subject (not the closing speed) is very high. The closing rate is less with the longer lens, because the distance to the subject is greater, while the speeds remain the same. That’s why you are getting more keepers, because the "rate" of change is less.
Kid stuff usually qualifies as "action" photography. Try to keep the shutter speeds above 125th, whatever that takes. The use of flash allows shutter speeds up to the flash sync speed, usually 1/200th to 1/250th on Canon cameras, so the use of flash is highly recommended (the XT is 1/200th, which I'll bet you already knew.) You mentioned using 1/100th to 1/125th, but there is so little ambient light, you might as well go to full flash sync speed. That probably won't affect focus speed however.
I would recommend more ambient light which will help the auto focus and allow more ambient light shots without the flash. Today, you can get daylight balanced Compact Fluorescent (CF) bulbs and 40" Daylight bulbs that are pretty close to continuous light. The CF bulbs are usually the newer high-speed ballast technology, so there's less worry about the power-line cycles. Try to get up around 500-1000 watt incandescent equivalent (or more) per room. You still might have to use high ISO, but Canon cameras accommodate that pretty well. If that means "planting" a few extra lights for a shoot, just consider them photographic accessories.
One technique you might try, I saw someone use it after my kids were grown, is to move the camera during the shot. You hold the camera beside you and shoot while you move the camera in an arc away from the subject (think bullfight and torero/toreador). What you are doing is trying to match the speed and direction of the camera with the speed and direction of the subject, your toddler. You generally keep the composition loose and crop in later. This is supposed to keep the subject to camera distances constant through the shot. I never tried it, so I don't know if it will help or not.
I doubt that the 20D would make too much difference in low light focus speed, but a 1D series Canon does have better low light capabilities (sensitivity) and faster focus so a 1D MKII or 1D MKIIN probably would improve the keeper ratio. You still won't achieve 100% focus without using the other mentioned techniques and improvements, even with the best camera and lens, so more shots is the only way to insure more keepers.
BTW, shooting a portrait of a non-moving subject at f2.8 is not easy, so expecting to shoot a moving target at f2.8 is predictably going to be difficult. You are doing many correct things, with the longer zoom and flash, so persist and conquer. Your toddler is worth it, right?
Best,
ziggy53
Moderator of the Cameras and Accessories forums
I have only one minor suggestion - in very dim light the peripheral AF points in the 20D or 350xt viewfinder do not work very well.
You might try using the center AF point only as it is more sensitive, and focuses horizontal and verticle lines unike the more perepheral AF points.
Be aware that using the central AF point tends to make you want to focus and then recompose, and this is not a good idea shooting near targets with wide apertures.
Try using the focus assist light in the flash also
Moderator of the Technique Forum and Finishing School on Dgrin
I just want to take a post to thank you for this info, Ziggy. I will soon be adding lighting to our very dimmly lit family room and have been thinking about how that will affect photography of little ones in the years to come. This is excellent.
Thanks much for posting it.
www.ackersphotography.com
I will try Greg's MF tip sometime. My only concern is that I will become kind of passive so to speak. I will have to wait for them running into my focus so I can snap the picture. Obviously if they don't than I won't have any thing to shoot.
Ziggy I will keep the distance from my kids so the relative speed between the camera and the object is slower. I will try with the highest sync speed at 1/200s. Shall I use AV or manual mode? I still want the background be blur if it becomes distractive. Maybe I should still play with ISO or just blur the background with PS?
When I use the the daylight balanced Compact Fluorescent bulbs with main light source, do I have to adjust the WB? Currently I am using AWB which works pretty good for me in most situation.
Your comment on 'shooting a portrait of a non-moving subject at f2.8 is not easy' makes me feel better, because I am having difficulty with it. Any suggestion of how to handle big aperture? Compare with prime lenses 2.8 is really not that big. How do people shoot with aperture wide open and get good result? Is tripod a must?
Pathfinder, thanks for the tip, ever since I read the thread about focus and recompose discussion on this forum. I try to avoid it as much as I can. Now I just have one extra thing to do, pickup a focus sensor before focus and shoot. It slowes me down a bit. I am wondering if I should just go back to multi-point focus and take few pictures instread of one, hope that there might be one that focused on the right place?
Eric
Yes, use what works, but try both.
You are thinking that you have to accept the background from where you are standing. You may want to reposition yourself with respect to a better background. "Fixing in post" is sometimes possible, not always practical. If you can alter/simplify the background, then do that. Don't limit yourself to what is, think of what might be. (That said, I still take plenty of "snaps" with cluttered background. Sometimes the subject or the event or whatever is more important to document poorly than not at all.)
If you are happy with the AWB, then you are probably really close. You can always take a controlled photo with a white target, and some colors which you might find common. You can use the PS eyedropper to check the white, to see if it's pure and balanced, and if not, you can develop a simple action to compensate, as long as you have the same lighting setup.
Fluorescent will probably never be perfect, certainly not as good as daylight or flash, but it is very conventient. If the color balance is close, I wouldn't stress about it, unless your getting paid or have a client that's anal about color (or heaven forbid, a DP/Designer/Artist who's anal about color.) "Hot" incandescent and Tungston are also more continuous light, but they are more problematic and even dangerous.
You can also shoot in RAW format, which gives you the ability to adjust WB after the fact. In mixed source lighting, you really need to shoot RAW.
There isn't a single, simple solution, otherwise everone would do it! Most large aperture portraits are shot in very carefully controlled environments and settings, ideally a studio. Sometimes you see environmental portraits, but there you see both large and small aperture stuff.
Most of the time, the eyes are the things you want perfectly sharp. Check out Yuri Pautov's images and the eyes are almost always the most striking feature. Other than that, you need enough DOF to cover the situation. Experience is the best guide and you will learn what works best with what situation and lens.
A tripod is almost always a benefit for serious adult portraiture and image studies of non-moving subjects. I doubt that your toddler qualifies for either of those things.
ziggy53
Moderator of the Cameras and Accessories forums
Eric