Looling for a good low light indoor lens.

[Justin]

I am looking for a good indoor low light lens for my Canon 60D.  I have been using a 50mm f/1.8 lens but it seems like I am always too close and I can't always back up because I run into furniture or I am up against a wall.  I usually take pictures of kids & pets so a fast lens is preffered.

I had my eye on Canon's 17-55mm f/2.8 IS USM but it is a little on the spendy side and I'm not sure I need a zoom lens, when I can just take a step forward.

I am also looking at the EF-S 24mm f/2.8 STM and the EF 24mm f/2.8 IS USM.  Other than the Image stabilation, is there much a difference between these two lenses?  Is image stabilation worth the extra $450.00?

[cale_kat]

It is also worth mentioning that the lenses with a 1.4 or 1.8 maximum aperature typically perform very well when stopped down once or twice. The benefit being that the higher you start, the better position you will be in to take advantage of natural light even when stopped down.

[TCampbell]

That's true... "extremes" of lenses are seldom their sweet spots of performances.

I mention the hazzard of very low aperture only because beginners may go from a kit lens with variable focal ratio, then learn that some lenses offer much lower focal ratios which collect substantially more light.  If you compare a kit 18-55mm f/3.5-5.6 lens at 50mm (which would be limited to f/5.6 at that focal length) to a "nifty fifty" 50mm f/1.8 that's 3 and 1/3rd stops (about 10x more light).  Ten times more light sounds fantastic on it's face...

Yet it's also important to consider that while the light collection goes way up... the depth of field becomes much narrower and this may become so narrow that you may not be able to get everything in focus that you actually want in focus without considering subject placement.

Commonly in cinematic photography only one "person" in the scene might be focused... deliberately de-focusing other people in the scene and drawing the viewer's attention to the person in the scene that the director wants them to see.  In traditional photography, if two children are in the same photo, more commonly the photographer probably wants both to be focused.  If that's the case... you may need to nudge the focal ratio back up to achieve that goal.

My original post was really to point out that very low focal ratios (f/2 and lower) don't necessarily solve the light problem without any side-effects so... use with care.

[ebiggs1]

"...  very low focal ratios (f/2 and lower) don't necessarily solve the light problem without any side-effects so... use with care."

There is no free lunch.  You give to get.