zug55 Loc: Naivasha, Kenya, and Austin, Texas

Very relevant question. There is no good answer without knowing what camera OP is using. Modern mirrorless cameras create usable images at ISO 6400 and higher; for DSLRs the threshold is lower. Full-frame cameras do better than APS-C cameras. Cameras with lower pixel counts generally have better low-light properties. Is the camera image-stabilized? The lens? And so on. Generally, 1/4 of a second invites lots of motion blur, regardless of equipment.

R.G. Loc: Scotland

When using a tripod, if the subject or subjects are truly stationary you should be able to use as slow a shutter speed as you want. If you're getting motion blur then there has to have been movement. With vegetation even a gentle breeze or in your case a draught can be enough to cause movement, and as you said, people breathe etc since they aren't statues.

Others have mentioned causes of camera shake, including people walking about on wooden floors, mirror slap etc.

These things aside, you need to be sure that softness is motion blur or caused by camera shake. If you're using apertures that are wider than you're used to, you may be underestimating how shallow the DOF is, especially if the indoor location forced you to stand close to the subjects.

larryepage Loc: North Texas area

It has been quite illuminating to follow this discussion and to see what it reveals about the knowledge level of photographic fundamentals here. It also speaks volumes to the level of lore, misinformation, and simple "wrongness" among photographers here and everywhere.

First...based on the post, there is absolutely no need for the OP to include an image. While it might be helpful to know what camera is being used (a few have functions that can help), that's not where the answer probably lies, either. And yes, some newer cameras might do better at a more appropriate ISO choice than others.

Second...if the photographic community did not unnecessarily complicate flash photography, the OP would probably have learned long ago to use a speed light with a simple diffusion dome to take completely serviceable, attractive images of the people at the function. He might have even discovered the benefits of a simple flash bracket to improve those images without even having to face the dangers and pitfalls of bounce flash or off-camera flash.

The only problem here is that a 1/4 second shutter is way too slow for taking photographs of people. Even with three stops of image stabilization, this is equivalent to 1/30 for the photographer, but it's still 1/4 second for any subject movement. It's not "shutter shock" or mirror shock, or any other imagined equipment shortcoming. It's just too long an exposure.

Oh...in reality, there may be a second problem. If the room is so dark as to require a 1/4 expisure time, it may also be true that is dark enough that the autofocus system can't see well enough to do its job correctly. Even with a focus assist light, the system may say that it's working when it's really not quite doing what it is supposed to.

So...to the OP...please don't despair or be overwhelmed. If you have a similar opportunity again, just
Find the brightest attractive spot in the room.
Turn on the Flicker Reduction function if available.
Take a deep breath and select a reasonable ISO (maybe 1250 or 1600).
Use Shutter Priority at 1/30 or 1/60.
Remind your subjects to stand still.

burkphoto Loc: High Point, NC

Many portrait and group images taken 120 to 150 years ago were made with exposures longer than 1/4 second. The fact that most subjects were recorded sharply was remarkable, until you realized that the photographers used metal head braces behind their subjects, instructed them in WHY they had to remain stationary with their eyes open throughout each exposure, reminded them multiple times to do so, and so on.

Perhaps I should clarify the role of stabilization systems. Some of them are now capable of eliminating up to 8 stops of camera shake. CAMERA SHAKE. That is why we use tripods, right, to eliminate camera shake? It is also why we use mirror lock-up on SLR/dSLR cameras and electronic shutter mode on mirrorless cameras. And it is the only reason to use stabilization, whether IBIS or ILIS (VR/VC/IS/OIS, or whatever the lens manufacturer calls it).

Unfortunately, nothing can eliminate subject movement short of stopping the subject from moving. But you don't need a tripod for group photos if your camera and/or lens combination has a sufficiently advanced image stabilization feature.

The point of reasonable shutter speeds is to reduce the effect of subject movement to negligible levels. How fast? It depends on the speed of the subject. I generally consider 1/30 to be marginal, 1/60 to be usable for most photos of people, and 1/125 to be my safety zone. Those three speeds are for 50mm lens on full frame, 35mm lens on APS-C, or 25mm lens on Micro 4/3. Double any focal length and you will need one stop faster shutter.

Can you use available light? What kind of light is it? If mercury vapor or sodium vapor, results are likely to be plug-ugly, even if you use custom white balance. With fluorescent or LED, it really depends on the brand, color temperature, and CRI rating of the lamp. Some buildings just have marginal lighting. 277-Volt commercial lighting can be tricky, even with a camera that has a flicker-free setting. Cheaper lamps and lamp ballasts can create horrible flicker and color temperature shifts to go with it.

This is an example of a cheap, industrial lighting grid output. It's a photo of a 2'x4' ceiling "troffer" with four, 48", 40-Watt GE Cool White fluorescent tubes in it, powered by a standard 277-Volt industrial lighting circuit. I used a Canon 50D at 1/1250 second shutter speed. The images were taken in a burst of 6.3 frames per second. Note the awful shifts from frame to frame in both white balance and exposure! At 1/30 second in that room, I got minimal shifts and could rely on custom white balance for casual photography. At speeds faster than 1/60, results were unacceptable. Video was ugly without auxiliary lights.

If that's not an argument for the judicious use of flash or photo grade LED panels, I don't know one.

PHRubin Loc: Nashville TN USA

Personally, I don't like to use less than 1/60 sec. and faster, if possible. Since my camera can do flash at 1/250, and the flash itself is only milliseconds long, that combo really helps freeze action. I have to work really hard to not get motion in hand-held no flash shots.

CHG_CANON Loc: the Windy City

Use 1/30 to 1/60 sec to 'freeze' people who are suppose to be standing still. A quarter second is way too slow. Raise your ISO to achieve the necessary shutter speed, or open the aperture to give up on a depth of field, or a mixture of both.

bikinkawboy Loc: north central Missouri

Years ago I was taking photos of the moon with a D5100 with a 500mm lens with 2x teleconverter. I could never get them as sharp as I figured they should be. Ends up the mirror flipping up was causing some shake.

The camera doesn’t have the delayed shutter like some. So I took a metal tripod for a level (survey level) stripped down the busted level and made an adapter to fit the camera. I ended up adding a bunch of steel to it for ballast and I was then able to get extremely sharp images. It probably weighs 25-30 pounds but doesn’t shake even in strong winds. What also helps is that the tripod is made for stepping the points on the legs into the soil.

You might consider how solid your tripod is.

cmc4214 Loc: S.W. Pennsylvania

No

Tom Shelburne Loc: Roaring Gap NC

Learn by your mistakes and through the guidance of this fantastic panel! Many thanks to all for your input and wisdom. I have purchased book you recd on flash photography and will utilize that medium more effectively. Thx for explaining the science of hyperfocal distance!- Great group ! Three years into photography and love to learn. Very nervous about friends small wedding they asked me to shoot.Tom

foathog Loc: Greensboro, NC

That was a rhetorical question. LOL

uhaas2009

On a tripod with cable release you can shoot in any shutter speed. And your tree isn’t moving.Sure some tripod can have vibration…..
I guess it’s more how you focus or how you let the camera decide where to focus. If you set single focus point then you decide where to focus on your subject. If the camera decide where to focus then you may get lot of errors.

DavidM Loc: New Orleans, LA

As a rule of thumb, your shutter speed needs to be double (or more) than the lens focal length. So, for example, if using a 50mm lens, your shutter speed should be 1/100th sec or faster. If shooting with a 75mm lens, your shutter speed should be at least 1/150th sec.

Also follow this video.., It has always worked for me regarding using flash.

https://www.youtube.com/watch?v=wLeaX_WXUJ8&t=2s

george19

Is the tree sharp? If so, probably people motion. 1/4 second is too long. At best, 1/15 or 1/30 second, ideally at least 1/60. Bump ISO, open the lens, learn flash.

PattyW60 Loc: Northwest Illinois

Thank you for sharing this information!

montephoto

PLEASE, (and I say this with kindness and respect) do not photograph this wedding until you have a lot more experience and education. Learn to use a flash so you can do it in your sleep. Do you have backup equipment in case of equipment failure? Imagine how you will feel if images turn out poorly, like your Christmas images. It is a wedding. Never practice on a client, or a wedding.