Photographers, what's your compromised variable?

Hard to explain in just a title, but I'm interested to see how photographers manage low-light photography (specifically events).

I've got an event next week, one I've done before and the light is rather ambient. I don't have a flash for the night unfortunately, but please don't say go get one.

The event is basically lots of chaotic and un-organized spur of the moment group shots/portraits mixed with dancing.

Before I shot the event with the 50 1.8, and my technique that night was keep the aperture big, (F2, 1.8) and reserve my ISO.
The pictures although reasonably clean aren't sharp, so I'm thinking this time I'll fix my aperture at F2.8 as long as I can to retain some sharpness, and ride the ISO higher.

So POTN, what do you prefer to do...

- Sacrifice sharpness/focusing for the sake of clean images
- Sacrifice clean pictures for the sake of sharpness and bigger DOF

Thanks for replies, and yes... I am a n00b!

A noisy but sharp picture is generally better than a blurry but clean picture.

Your gear list shows you have a 7D, which gives good images at pretty high ISOs. You don't say what settings you were using, but I'd say go to at least ISO1600 to give your shots a chance with a reasonable aperture and shutter speed.

I know you said not to, but flash is probably the best choice. Otherwise, shoot at 2.8 so you have some decent DOF and pump the ISO.

Madweasel wrote in post #9882687
Your gear list shows you have a 7D, which gives good images at pretty high ISOs. You don't say what settings you were using, but I'd say go to at least ISO1600 to give your shots a chance with a reasonable aperture and shutter speed.

I needed to be at ISO 3200 at the least, to be honest I think I'm going to have to be at 4000+ to get a decent speed. Still, I think I'd rather crank the ISO... easier to fix.

Sounds like your going to be relatively close. Use the pop up flash with a little diffuser.

Noise (even though it kills finer details) can be dealt with in editing to a good extent and for prints its even easier to hide away. However motion blur is pretty much unremovable and even minor cases can take a lot of work to correct (and look good).
I'd go for noisy images (even though I hate them) over motion blured ones. Also remember that if you expose a shot well (histogram buntched over to the right as much as possible without overexposing and hitting the right side limit) that will also help to hide noise away.

Get a flash. Or use the pop up flash.

I need to keep a min shutter speed. A blurry photo is worthless. Noise can be dealt with.

It's pretty simple, IMO.

You don't want to use flash (I would, but you said you can't/won't).

You need a certain depth-of-field for the shots you need.

Shutter speed can only be so slow, or you're going to get camera shake or motion blur.

ISO is your only choice. Blurry pictures do not print well. Noisy ones can be dealt with, to an extent.

Seriously, though: consider a flash. Your photography will thank you.

Honestly, the best thing to do would be to get a flash. That way you can actually control the light that you have. There's low light, there's bad light, and there is bad low light. At an event you generally can't choose what kind of light you'll be shooting in, and that is where the flash comes in handy.

That said, I think your predicament is a bit of a false one. There is no reason why you shouldn't be able to get reasonably sharp shots at f/2 with the 50 f/1.8 (as long as you manage the DOF when shooting multiple people).

As the others have said, sharp and noisy is preferable to motion blur, but you're asking about noise vs. dof. I think you have to decide what your boundaries are. You have to determine what is your highest acceptable ISO and what is your minimum acceptable shutter speed given the conditions? It's really a matter of taste, but you should be able to get usable images at ISO1600 or even ISO3200 if you need it. But imho I would try to stick with ISO1600 if you can swing it (even if it means shooting at f/2).

It's less motion blur, more just general softness and too shallow DOF.

I've done some tests comparing histograms with the venue and tests I can do here, I can probably get away with F2.8 and ISO 4000 most of the time. I'll have to play it by ear really.
I would borrow a flash, but I can't access my source this week unfortunately.

I'll show you the most difficult light I'll have to work with, as you can see I'm having issues with DOF in this picture...

F2, 125th, ISO 5000

benesotor wrote in post #9882709
I needed to be at ISO 3200 at the least, to be honest I think I'm going to have to be at 4000+ to get a decent speed. Still, I think I'd rather crank the ISO... easier to fix.

You're a newbie asking for advice. The best advice I can give you is to get an external flash with a diffuser. You can fool around with ultra high ISO and wide aperture, trying to fix the noise in post and hope the image looks OK. Or, you can do what 99% of wedding photogs do at dark reception halls and use a flash.

I shoot a lot of local shows with my 7D. The light is always bad and a flash would not be feasible (I want to preserve the look and feel of the show). I shoot the shows with my 17-55 f/2.8, 28mm, f/1.8, and 50mm f/1.4. I shoot with the aperture with open and ISOs around 3200-4000. This will keep my shutter speeds around 160th or better (if I get over 200th I will back off on ISO). Even with wide open aperture if you are not right upon the subject DOF will be fine for the subject (though for and background will be blurred). This took me some experimenting to get like I want it. Be sure to shoot RAW which will allow more flexibility in post vs jpeg. A little noise reduction, sharpening and resizing will get some great images. I usually size the images around 1600X1200 pixels and they come out quite nice in my opinion.
Here is my blog of you are interested in what I am talking about, though the images are small you will get an idea.
www.matteroffactart.wo​rdpress.com.

timbop wrote in post #9882902
You're a newbie asking for advice. The best advice I can give you is to get an external flash with a diffuser. You can fool around with ultra high ISO and wide aperture, trying to fix the noise in post and hope the image looks OK. Or, you can do what 99% of wedding photogs do at dark reception halls and use a flash.

I realise using a flash is the best thing to do... but unless I buy one, I can't have a flash for wednesday.