I am doing my first photo shoot of a birthday party for a friend. I wanted to know which lens would be the better option to use for this. I have a Canon 50mm f/1.8 prime lens as well as the standard 18-55mm IS kit lens and a 55-250mm IS tele-zoom lens. So far, just getting to know my camera I have mostly played around with the kit lens. Now I'm not sure which of the others would be a better option.
Assuming that your camera has an APS-C sensor (18-55mm IS kit lens tells me that it does), the 50mm f/1.8 is probably a good bet for shooting portraits. Typically a photographer wants to use something around 85mm-100mm (on a full frame sensor) for a nice sharp portrait. Since your camera is APS-C and probably multiplies the focal length by 1.6x, you're looking at about an 80mm equivalent from your 50mm lens which gets you close enough to the sweet spot for portraits. Also the Canon 50mm f/1.8 is way sharper than either of the other two lenses that you mentioned.
Summary: Unless you're using a 5D or 1D, you'll be just fine with the 50mm lens for portraits. If you want more candid, far away shots, try the 55-250, but for sharp portraits, the 50 is your best bet.
I'd take all three lenses with me.
Since you don't mention it, I'm going to assume that you don't have an external flash and only the built-in one. The built-in flash will help you in a pinch, but it's not very powerful and it doesn't look very good. I would aim to either not use the flash or use it only for a little fill.
First, if it's indoors and dimly lit, the 50mm may be the best and only solution simply because you can shoot at a larger aperture to get a shorter shutter speed that you can freeze the action.
If you've got a little more light, you can use the 18-55. Personally, I would find the 50mm too long for indoors shooting and would probably use the 18-55 in the 18-30mm range to get some more environmental portraits or small groups.
If you want to work on the long end of that lens -- 55mm -- for some tighter shots, you might switch to the 55-250. On the 18-55 at 55mm the largest aperture is f5.6. On the 55-250 at 55mm the aperture is f4 -- one stop brighter! That may be enough to let you get a shot.
I have the same 3 lenses that you mention with the Canon 550D and a Metz flash. I've found that the 18-55mm kit lens does quite well when stopped down to f/8 and used with the flash indoors (bounce flash in particular). Make sure that you have the portrait picture style preset in use if shooting JPEG to make the portraits look warm. The lens covers the ideal focal lengths for indoor portraits including group shots. You can also get by without flash by bumping up the ISO - 1600+ is usable on the 550D, especially if you plan to share online exclusively.
The 50mm f/1.8 prime is also quite useful for individual and small group portraits. You can use wide apertures to blur the background. It gives pretty sharp results without having to stop down, and you can do without a flash to get decent shutter speeds.
Since you are planning to shoot a birthday, make use of the burst\continuous shooting mode to capture the important moments like cake cutting. This is also handy for group photos to reduce the chance of capturing people with their eyes closed. The prime again helps here, as it can be used in burst mode without a flash.
Also, be careful when changing lenses during the party - good time to get unwanted particles into the camera\lens.
I would suggest 50 mm and 18-55. Below are the reasons
- 50 mm is great for portraits.
- if the party is not well lit, you will not have lot of difficulty with 50 mm, but 18-55 will have trouble in low light.
- 50 mm will not be wide enough to cover medium to large groups. That is where the 18-55 is going to help.
Having said that, if you don't have a second camera, it is going to be a pain to keep switching lenses and you might miss the moment. If I were you, I'd shoot most pictures with the 18-55 and then after all the action is over, shoot portraits with the 50mm
I'd go with the 50mm f/1.8. Assuming you are on a crop-sensor camera a 50mm lens will be roughly equivalent of about 80mm. Combined with the wide aperture this will afford you the ability to shoot wide open or even at f/2 - 2.8 with a great depth of field and sharpness that the 18-55 just won't give you.