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bTaryag
04-01-2007, 08:58 PM
Hello all.

I was asked by a neighbor to shoot a picture of all her grandkinds posing together. (Don't ask how many, it's in the twenties). She knows that I am not a pro, which is why she asked me - she doesn't want to pay for a pro!

The pictures will be taken indoors, but in an area with good/decent indoor lighting. Here is my dilemma: I plan on using my Canon A630, and would like to use the smallest aperture available (f8) to get all the kids in focus, which in turn will require a slower shutter speed. Flash will not be of much use as I will have to be far back to get everyone in the picture. I can raise the ISO, but that will cause the picture to be noisy.

My question is as follows. I will be using a tripod, so a slower shutter speed won't cause problems on my end. However, there may be problems on the other end, if a kid moves while I take the picture.

What is the slowest shutter speed I can use without this being a problem. The kids will be posing for the pictures, not running around, so I guess I can go low. The question is, how low can I go?

SpecialK
04-01-2007, 09:24 PM
On a tripod, 1/30 or 1/60th would be a reasonable shutter speed. You may not need to be at the smallest aperture, anyway, because you can be back, say, 12 or more feet which will help your focus issue.

Chrisku13
04-02-2007, 12:22 AM
Plus, as I understand it, the point and shoot's smaller sensor would make it more difficult to obtain much DOF. I have the A630, and find that even with a larger aperture, things stay pretty much in focus. I would say try to lower the aperture and possibly use flash for a fill-in. You could keep the camera in aperture priority mode, and just use different ones to see which works best. With that number of variables (grandchildren), I imagine it would be hard to use a slow shutter speed without some kind of movement going on. Unless my family's the only one with kids that lack a proper attention span. It's weird, we never seem to.......

Hey, how was everyone's April Fool's Day?

avi777
04-02-2007, 12:41 AM
Hello all.

I was asked by a neighbor to shoot a picture of all her grandkinds posing together. (Don't ask how many, it's in the twenties). She knows that I am not a pro, which is why she asked me - she doesn't want to pay for a pro!

The pictures will be taken indoors, but in an area with good/decent indoor lighting. Here is my dilemma: I plan on using my Canon A630, and would like to use the smallest aperture available (f8) to get all the kids in focus, which in turn will require a slower shutter speed. Flash will not be of much use as I will have to be far back to get everyone in the picture. I can raise the ISO, but that will cause the picture to be noisy.

My question is as follows. I will be using a tripod, so a slower shutter speed won't cause problems on my end. However, there may be problems on the other end, if a kid moves while I take the picture.

What is the slowest shutter speed I can use without this being a problem. The kids will be posing for the pictures, not running around, so I guess I can go low. The question is, how low can I go?

I would say, since you are not gonna use use any zoom, you could try at the widest aperture and you wouldn't have any DOF issue if you have enough distance between yourself and the crowd. However you should try to get in some good lighting to cover them all. Make sure they are all front lit and then keep the ISO as low as possible. I would suggest you have a shutter speed of anything over 1/100 - knowing that kids will be kids. Hope this helps.

AlexMonro
04-02-2007, 03:12 AM
You don't need to worry about DoF to get all the kids in focus. Assuming you're using the wide end of the zoom range, to fit them all in the frame, the tiny 1/1.8" sensor of the A630 will give a sharp focus zone from about 1.5 metres to infinity, even at f/2.8 (hyperfocal distance 2.7 metres). See Depth of Field calculator (http://www.cambridgeincolour.com/tutorials/DOF-calculator.htm) (remember that this uses the actual focal length, not the 35mm equiv).

If you set ISO 100 for minimal noise, you should still get a shutter speed of at least 1/30 - 1/60s, if the lighting is reasonably good - you might not even need the tripod, and if the kids are keeping fairly still, motion blur should be no problem.

It might be worth using a grey card, or piece of plain white paper, to set a custom white balance.

bTaryag
04-04-2007, 11:05 PM
Thanks guys, the big day is tomorrow!

I went to a camera store (and there are so few of these left!) to buy a gray card, and on a whim I bought an external slave flash. It is an older Phoenix model, so I got it cheap.

I could simply use this flash pointed at the kids, but I am not a big fan of using the flash - red eye becomes an issue, and people wind up looking "harsh".

I played around with it a bit, and when the head is pointing at a (white) ceiling on a bit of an angle, it bounces back light to the whole room, resulting in a much softer and even look. This too, lets me reduce the shutter speed by a whole lot.

I plan on using the built in flash on it's lowest output, which will trigger the slave which will be set to the highest output. Together with the lighting of the room, should be enough.

avi777
04-04-2007, 11:16 PM
Good luck and don't forget to post a few of the pics you take.

AlexMonro
04-05-2007, 02:31 AM
If you use a mixture of bounce flash and room lighting (incandescent or flourescent), it's going to complicate the white balance. The flash will probably produce daylight balance, though it will be coloured by the ceiling unless that's pure white, but the room lights could be anything. A fast shutter speed will minimise the effect of the room lights, but it might be best to turn them off and just use the flash and any daylight coming through the windows.

If you place the grey card in a corner of the shot where you can crop it out, you can use that to correct the colour balance in post processing, or if there are any pure white objects in the shot, you could use them.

Bounce flash is probably the best way to go though.

bTaryag
04-17-2007, 11:05 AM
Sorry, for not posting earlier -

I got some very nice shots. The kids were cooperating, so that helped.

With the external flash and all the room lights on, positioned in a way that the light from the windows hits the kids, I used a 1/50 shutter speed together with f8, and ISO of 100. I used gray card to get accurate white balance.

I used the 3-2-1 trick, and I got a few shots with everyone's eyes open (that a total of 42 eyes!).

On my PC afterwards I adjusted the color temperature to make it look a bit warmer.

We selected the nicest picture, and it is now 24 by 36 (or 20 by 30, I don't remember which she chose) hanging in my neighbor's house. She is very happy.

Unfortunately, she doesn't allow me to post a picture online. Next time I'll have to make it a precondition.

Thanks all!