Focusing problems

[pgowder]

This weekend I photographed a Native American Pow Wow using a Minolta 7D. During the faster dancing, I had problems with the focusing. I was taking the photos in continous mode. The camera would focus on different places of the person's outfit and not have the whole person or thier face in sharp focus.

What can I do to improve this??

I'm still working on processing all the photos, but I've posted some here:

http://www.powwows.com/galleries/sho...=last7&cat=562

[Stephen Lutz]

This weekend I photographed a Native American Pow Wow using a Minolta 7D. During the faster dancing, I had problems with the focusing. I was taking the photos in continous mode. The camera would focus on different places of the person's outfit and not have the whole person or thier face in sharp focus.

What can I do to improve this??

I'm still working on processing all the photos, but I've posted some here:

http://www.powwows.com/galleries/sho...=last7&cat=562

First, let me say I enjoyed your images. Very good color!

Now, let me ask some questions: what lens were you using, and what was it's aperture? What was your shutter speed? What ISO did you use?

From the looks of your photos, it appears to me you were some distance from them, possibly using a 70-200 2.8 lens, wide open or close to it. It also looks like you were using ISO 800 and a fairly slow shutter speed. I know the Minolta has built in IS, which is great for static subjects, but with won't do a thing for sugject movement.

When I shoot in relatively low light, a shutter speed of 1/200 of a second is about the best I can expect at ISO 800. Since focus on a particular part of the subject is important, I suggest you switch to a single focus point and put it directly on the face of the subject. In this way, you will maintain focus on the face. You can also try a higher ISO, if it yields acceptable results. Good luck!

[Chunk]

I also enjoyed your photos. What a riot of color! The composition of these shots was excellent considering all the subject movement.
Steve has good suggestions. Anything to get shorter exposure times of course will help. On some of your softer shots it seems to me like it may be camera movement that contributes to the softness.
Have you tried taking indiviual photos rather than shooting in continuous? There might be less tendancy to move the camera and follow the motion of the dancer, instead holding the camera still and letting the dancer move into the frame.
Do you want any suggestions on presentation on the website?

[pgowder]

First, let me say I enjoyed your images. Very good color!

Now, let me ask some questions: what lens were you using, and what was it's aperture? What was your shutter speed? What ISO did you use?

From the looks of your photos, it appears to me you were some distance from them, possibly using a 70-200 2.8 lens, wide open or close to it. It also looks like you were using ISO 800 and a fairly slow shutter speed. I know the Minolta has built in IS, which is great for static subjects, but with won't do a thing for sugject movement.

When I shoot in relatively low light, a shutter speed of 1/200 of a second is about the best I can expect at ISO 800. Since focus on a particular part of the subject is important, I suggest you switch to a single focus point and put it directly on the face of the subject. In this way, you will maintain focus on the face. You can also try a higher ISO, if it yields acceptable results. Good luck!

I had ISO set to auto. I shot most of them with a 70-210 F4 on shutter priority usually 1/125 and f4. I had IS on.

What do you mean switch to single focus point? Is that a setting on the camera?

Thanks

[pgowder]

I also enjoyed your photos. What a riot of color! The composition of these shots was excellent considering all the subject movement.
Steve has good suggestions. Anything to get shorter exposure times of course will help. On some of your softer shots it seems to me like it may be camera movement that contributes to the softness.
Have you tried taking indiviual photos rather than shooting in continuous? There might be less tendancy to move the camera and follow the motion of the dancer, instead holding the camera still and letting the dancer move into the frame.
Do you want any suggestions on presentation on the website?

Thanks! No, I didn't try individual shots, I'll try that next time. It's hard though to have the dancer come into the frame since their direction isn't always predicitable!

Sure, what suggestions do you have about the presentation on the website?

[Stephen Lutz]

I must confess I know little about Minolta cameras, but I assume you have a grid of focus points to choose from. In Auto mode, the camera selects the active point that is closest to the camera, which may, or may not, be the one you want to use. On my 10D and Digital Rebel, I can either let the camera choose, or I can manually select a single focus point to be active. I usually choose the center point, since it is the most sensitive one of the group.

Check your manual, but I assume you can do something similar with the Minolta 7D. I also suggest you manually select the ISO. 1/125 of a second is a bit too slow for motion, though with IS it should be adequate for static shooting. WIth my 300mm f/4 IS I can get away with 1/125 or even 1/90 with static subjects. I suggest you get your shutter speed up a tad, and manually select your focus point and it should improve your focus accuracy. Good luck!

[another view]

The center focusing point (of five) is the most sensitive one in my Fuji S2 as well, it picks up both horizontal and vertical lines and it's the one I almost always use.

You do have some nice shots here, but the problem you describe is typical of low light, moving subjects and a short depth of field. On one hand, increasing the depth of field by closing the aperture would help minimize focusing errors, but you need all the lens speed you can get.

Here's what I do in a situation like that: Set the camera at ISO800 (looks pretty clean, as long as you're comfortable with it - try higher too if you can). Use a fast prime lens (85 f1.4 usually). This way, the viewfinder is much brighter (three stops brighter than f4) so AF has a better time of it although I probably wouldn't shoot all that much wide open. I'd probably use f2 or f2.8 and just expect some frames not to be in focus. Timing the action and trying to get one good one rather shooting on continuous will probably give you better results too.

One thing, it looks like you probably use auto white balance which did a pretty good job here. A custom white balance would help though and this is a good time to do it because of one main light source in the room (fluorescent or MH in the ceiling). I can see a bit of a greenish cast in the skin tones and yellows - however it's impressive for auto WB.

[pgowder]

The center focusing point (of five) is the most sensitive one in my Fuji S2 as well, it picks up both horizontal and vertical lines and it's the one I almost always use.

You do have some nice shots here, but the problem you describe is typical of low light, moving subjects and a short depth of field. On one hand, increasing the depth of field by closing the aperture would help minimize focusing errors, but you need all the lens speed you can get.

Here's what I do in a situation like that: Set the camera at ISO800 (looks pretty clean, as long as you're comfortable with it - try higher too if you can). Use a fast prime lens (85 f1.4 usually). This way, the viewfinder is much brighter (three stops brighter than f4) so AF has a better time of it although I probably wouldn't shoot all that much wide open. I'd probably use f2 or f2.8 and just expect some frames not to be in focus. Timing the action and trying to get one good one rather shooting on continuous will probably give you better results too.

One thing, it looks like you probably use auto white balance which did a pretty good job here. A custom white balance would help though and this is a good time to do it because of one main light source in the room (fluorescent or MH in the ceiling). I can see a bit of a greenish cast in the skin tones and yellows - however it's impressive for auto WB.

Thanks! I'll try those suggestions.

On the white balance, should I try a custom setting or set it to fluorescent?

I was using a longer lense to get closer, don't know if an 85mm would have been enough. Guess I need to look for a good 100 or 200mm.

[Stephen Lutz]

Thanks! I'll try those suggestions.

On the white balance, should I try a custom setting or set it to fluorescent?

I was using a longer lense to get closer, don't know if an 85mm would have been enough. Guess I need to look for a good 100 or 200mm.

For indoor, no flash, shots like this, I use either a 135 f/2 or a 70-200 2.8L. That extra stop over the f/4 lens you were using is really crucial to success in photo ops like this. Good luck, and with IS built into the camera, if you can find a reasonably priced 2.8 long zoom for Minolta, you should see significant improvement.

[Chunk]

Sure, what suggestions do you have about the presentation on the website?

When viewing the photos, I had to scroll the screen to see the full shot. That gets a little tiresome. As you can see on this screen shot the top half of the screen is taken up by 5 horizontal menus (with some repetition in them) as well as colorful banners and separating strips that compete with the photos for the viewers attention. I'd recommend simplifying the setup by consolidating the menues into just one horizontal or even putting them all on the lefthand menu and creating some nice blank space around the picture viewing area, making sure that the photos can be viewed without scrolling.

[another view]

On the white balance, should I try a custom setting or set it to fluorescent?

I'd do a custom WB. There are a lot of different types of fluorescent and the preset may get you a little closer but you're already very close as it is.

I use the 85 f1.4 because it's very fast and easy to handhold at slower speeds. A 70-200 f2.8 would be a good choice too but it's a little heavy and you'll need a faster shutter speed if handholding because of it.

[pgowder]

When viewing the photos, I had to scroll the screen to see the full shot. That gets a little tiresome. As you can see on this screen shot the top half of the screen is taken up by 5 horizontal menus (with some repetition in them) as well as colorful banners and separating strips that compete with the photos for the viewers attention. I'd recommend simplifying the setup by consolidating the menues into just one horizontal or even putting them all on the lefthand menu and creating some nice blank space around the picture viewing area, making sure that the photos can be viewed without scrolling.

Thanks, good suggestion.

[pgowder]

I'd do a custom WB. There are a lot of different types of fluorescent and the preset may get you a little closer but you're already very close as it is.

I use the 85 f1.4 because it's very fast and easy to handhold at slower speeds. A 70-200 f2.8 would be a good choice too but it's a little heavy and you'll need a faster shutter speed if handholding because of it.

The 85 sounds like a good solution for now. I don't know if or when I'll have the $$ for a 70-200 f2.8.

But will the 85 get me close enough??

Any other suggestion besides new glass is very much appreciated! Wish I could afford one, but I'm still working on paying off the camera right now!!

[another view]

I'm not familiar with Minolta's offerings so I took a quick look at B&H's website. I didn't see anything there other than an 85 f1.4 that would be a good low-light option. Nikon and Canon both offer an f1.8 version for a lot less money but I don't see that Minolta does - maybe something to check out to be sure.

Will an 85 get you close enough? I can't answer that - go back thru your shots and look at the EXIF data. It will tell you what focal lengths you're using and that should help your judgement. I have a feeling that an 80-200 f2.8 (maybe a used one?), possibly a monopod like Bogen's 680, and carefully timed shots might be the best bet.

[pgowder]

What about a teleconverter? Would I loose any stops with one?

If I bought an 85 or 135 2.8. Can I use it with a teleconverter and not loose any speed?

Thanks

[another view]

TC's always lose speed, and sometimes sharpness. A 1.4x will cost you one stop of light and a 2x will be two stops. With a prime lens and a good TC, you shouldn't lose much if any sharpness - it's with zooms that you can have most of the problems. I know Nikon has a TC specially designed to work with their 70-200 2.8 but I haven't used it - I'm sure it's good (but expensive). Minolta may have something like this too.

[pgowder]

Here are some I took this weekend. Same type of event but outside during the day.

I used a 70-300 Sigma f4-5.6.

I'd love to hear any suggestions on how to make these better.

Thanks!

http://www.powwows.com/galleries/sho...ry.php?cat=569