Why flash

[fishyone]

I am fairly new to photography and have mainly been shooting wildlife and flowers. Lately though I have been doing some portraits and taking pictures for my church. I got the 50mm 1.8 for church and for portraits, but am wondering how beneficial a flash would be for me. Is there much need for flash with flower/ wildlife pics, most of which are with the Sigma 70-300mm? I don't want to buy it and then have it sit in my bag collecting dust. I am looking at the Sigma EF 500 DG Super right now.

[steved110]

A flash allows indoor photography with slower lenses, by providing extra light. It can also allow fill-in flash to lift shadows from backlit subjects outdoors.

the sigma flash you are interested in is excellent value, and as such it would not really matter if you didn't use it all the time. My flash I consider indispensible - but it only gets used occasionally.

[Curtis N]

I use flash almost all the time for people shots, and almost never for anything else. Flash also has tremendous value for macro work, since small apertures are the norm for decent DOF and you'll need to offset that with more light.

This thread (http://www.photography-on-the.net/forum/showthread.php?t=207470) should be helpful.

[fishyone]

Thank you for your replies. Curtis, thanks for the link. I'll order the Sigma as soon as B&H are open.

[Curtis N]

Try http://sigma4less.com

[fishyone]

It looks like both B&H and Sigma are closed until the 16th. Any other reputable dealers out there?

[Curtis N]

You could go to Sigma's site and click the "Where to Buy" button. You'll get a list of online retailers, or a way to select local dealers by zip code.
http://sigmaphoto.com/where/where.asp

[accentodesign]

I got mine on eBay from 47th Street Photo for less than 200 bucks. I can't be happier with it.

[fishyone]

Thanks for all the replies. Looks like 47th Street Photo is going to get my business this time.

[Papaw]

Curtis,
I have always avoided flash as I felt it was so distracting and attrusive (sp?) when involving people. I have been very pleased with the outcome of the 35L to achieve this in most situations. However I see there are times the flash would greatly improve the outcome. I shoot manual and every time I use the flash there are shadows and the white balance becomes much harder to dial in. I am doing this with the auto setting on the 580 EX and wondering how to cut down the intensity of the flash. I have read the sticky on this and still don't understand how to control the flash.

Jack

[Curtis N]

Jack,

I'm assuming you're referring to indoor situations under tungsten or fluorescent lighting, and you're using manual exposure on the camera and E-TTL on the flash. Controlling the flash is accomplished by adjusting flash exposure compensation (FEC).

Mixing flash with ambient light in this situation will create white balance issues that are hard to overcome. The areas lit mostly by flash will have one color and the areas lit mostly by the ambient will be a different color. If you want to mix flash with tungsten or fluorescent light, it's best to put a gel on the flash to change its color temp to match the ambient. The sample swatch books from Rosco have gels specifically for this purpose. Change your shutter speed to manage the ambient exposure and adjust FEC to manage the flash. Direct flash with this approach will still give you noticeable shadows, but they won't be as bad as with strategy #2.

Strategy #2 is to overpower the ambient light and make flash the only significant light source. This requires completely changing the way you think about exposure. Set your shutter at 1/250, your ISO at 400 or less and your aperture at 4 or higher. You can open up the lens to blur the background if you want, but try to keep the needle in the viewfinder blinking on -2. This is the camera's way of telling you that the ambient light will be more than 2 stops underexposed and the flash will do all the work. This should rid you of white balance problems. At this point, it's a matter of adjusting FEC to get the exposure you want.

There are basically two ways to deal with shadows. If you have a low, white ceiling or a close, light-colored wall, bounce it. This turns the bouncing surface into a very large light source and shadows will disappear. The other method is to use a flash bracket to keep the flash above the lens, thereby putting shadows down behind your subjects where they can't be seen.

My usual approach in residential or office settings is to use strategy #2 with bounced flash. Chapter 3 of Flash Photography 101 details how to go about it.

[blonde]

curtis, have i told you before that you rock? if i didn't, i am saying it right now. i think i have read every comment you made about flash and every single time i am learning something new..

[Curtis N]

Snir Golan, you are kind.

Flash photography can be frustrating, but it's not as complicated as some people try to make it. When you think about a flash photograph as two exposures in one, then learn how your camera works so you can manage both exposures, it becomes a lot easier. At that point, it's a matter of analyzing your shots to determine what you would want to change to make them better.