Large aperture (1.8/1/4)

matseski · May 27, 2012

I will be studying in Germany in the fall for 4 months and want to get a faster lens to help with documenting my travels as castles and cathedrals are not known for their stellar lighting...

I will be shooting on a 40D so crop factor is in effect. I currently have a Tamron 17-50 f2.8, Canon 70-200 f2.8 IS, and Sigma 150 f2.8, so I basically have the whole range from 17-200 covered at f2.8. So I am looking for something on the standard to wide range of things with an aperture f1.8 or faster. I would like to have a lens designed for full frame cameras as my next body will be full frame.

I have a budget of about $500, so all of the Canon L primes are unfortunately out at this time.

My choices seem to be with associated used/best prices:
Canon 28mm f1.8 $400
Canon 50mm f1.4 $320
Sigma 24mm f1.8 $530
Sigma 28mm f1.8 $350
Sigma 50mm f1.4 $500

OR, I could sell my Tamron without stabilization and get the Tamron or Sigma 17-50 f2.8 with image stabilization, but I'm not sure if this will be worth the hassle.

I have been leaning towards the 50mm options due to their use as a fantastic portrait lens as well and that when not doing touristy things I rarely even have my Tamron on my camera as it is.

Thanks for the input!

TCampbell · May 27, 2012

You're about to trade one problem for another. You don't have a lot of light, so you switch to a low-focal ratio / fast lens. But now you have a REALLY shallow DoF -- which isn't going to create an overall sharp image either.

Keep in mind: If the subject isn't moving ... AND the camera isn't moving, then you can leave the shutter open as long as you like.

Do you have a nice light-weight tripod? You probably want a higher f-stop (small aperture) to get a broad DoF. A tripod will let you do that.

matseski · May 27, 2012

While I agree that a tripod is the ideal solution and while I dont have a carbon fiber tripod, I do have a really nice set of aluminum legs that I use for macro work, I know that many cathedrals and other such enclosed public places do not allow tripods and regardless of how light weight it is, carrying a tripod around all day is a nuisance. Also, most of my 'artistic' work is done with detail shots. I like to play with scale and perspective so I feel a shallow DoF would be a great tool to add to my bag. While I agree with you, I just don't feel a tripod best suits my shooting style in this application. I want to be able to run around and be able to take those unique shots, but also have the ability to snap those documentary style photos as a remembrance.