Originally posted by shang thanks a lot! so the 70mm ltd should be good enough for indoor use.
I think so - although of course, it's officially f/2.4. Some say that this is overstated, but if so, so are all my other lenses, because it's definitely about half a stop faster than my f/2.8 lenses.
Depending on the nature of the presentation, where you will be shooting from, and how you want to frame, you might find 70mm not an ideal focal length. Some people would say it's too long (definitely is for more casual indoor use - candids, etc), others would say not long enough if you are trying to emphasize the expression of the person giving the presentation more than the overall gesture. Most would probably recommend the DA*50-135 for this purpose. But that DA70 is cheaper, nice and small and light, and probably a good "compromise" focal length for your intended purpose.