lwerthe1mer wrote:
I took some photos at a birthday party recently. My camera was a Sony a7ii. My lens was the Zeiss 2.8 fixed lens. Based on the advice of a knowledgeable photographer, I did not use a flash. I did not use a tripod.
To what can I attribute the blurriness? Unsteady hands? Not focusing properly?
Any suggestions would be greatly appreciated.
Not sure you want to listen to that knowledgeable photographer any longer - my guess was maybe you didn't hear his/her entire advice in the proper context. There is nothing wrong with using flashes as long as you know how to do it properly. Most wedding photographers use flashes - think about it. But let's not get into that discussion here.
Your pictures blurriness are probably caused by 3 things:
1. Too low of shutter speed - I only looked at the exif for a few of your pictures and one was at 1/15sec, one was at 1/30sec and one was at 1/60. All 3 were shot at 35mm FL
2. People were moving around...
3. Too wide of an aperture
The rule of thumb to avoid camera shake (unsteady hands) is to shoot at 1/FL or faster so the optimum safe speed should have been 1/60. The one picture at 1/60 that was blurry, unless you really have unsteady hands, was caused by people moving around. I'm a bit surprised that your camera anti-shake feature didn't save the day here - maybe it did but it can't do anything against fidgeting people...
In a couple of pictures with multiple people...some are clear and some are blurry...that might have to do with your aperture being set to 2.8 and it didn't have enough depth of field to make sure all people - staggered front to back - are in focus.
So when you shoot indoors where you know the light is low, you need to make sure you have high enough shutter speed and that means you need to use S (shutter speed) mode and set the speed yourself...in this case I'd set it at 1/100 if people are not moving or fidgeting and even faster if they move. Also, in cases of group picture, you want to set the aperture A to something like f/4 or f/5.6 instead of letting the camera pick for you - it always goes widest which is 2.8 for your lens.
In this case, you need to set both shutter speed and aperture, I'd recommend go to Manual mode with Auto ISO so the end result still is automatic except you get to control the speed and depth of field.