Headshots

I am helping my church as the assistant photographer. My first assignment was to shoot some headshots of various people for the website. These are not typical thumbnail shots as they wanted high detail photographs they could manipulate and use as the page header for each respective ministry. To say this was a learning experience is an understatement. I spent some time on the day before practicing on my daughter in the living room. Lighting was the big challenge. I don't have an external flash and I hate the harsh appearance I get when using the onboard flash for portraits. I used a coffee filter to diffuse the light which worked fairly well in my living room. Unfortunately, this did not work nearly as well at the church even though the background was almost identical. The shots came out very dark even though they looked properly exposed on the LCD and the histograms looked OK (EDIT - A second look at the histograms shows they do NOT look OK. I can see a large spike in the middle and a smaller spike on the left with nothing on the right. Clearly underexposed. This is something I need to remember when I set up my practice shots next time.) All I can say is thank heavens for RAW. I was easily able to correct the brightness level and the Canon software did a good job of balancing the skin colors.
Besides purchasing an external flash (which I cannot afford right now), I am not sure what I would do different next time. I definitely would shoot RAW+JPG for important items like this. That was a life saver. I might overexpose by at least +1 and maybe even +2 next time if I used the diffuser. I don't want to go to far as it is easier to pull detail out of a dark photo. If I overexpose too much and blow out the highlights, there is no saving the detail from that.
I am also deliberating on whether I made the best lens choice. My kit lens is faster than my zoom, so I might get better results from the lighting. I try to avoid shooting with the kit lens at 55mm as I think images are a little soft (I have not done tests to prove this though). Benefits to using this lens would be that it lets in more light and the flash would have been closer to the subject. Drawbacks would be somewhat less depth of field than using the 75-300. I need to think about this some more. It might be time to make the homemade softboxes from the photography lessons on www.morguefile.com and use those instead.