questions re my new 50mm 1.4

puyjapin · Jul 25, 2009

ive bought the 50mm f1.4g for my d40, which will AF on it. I have literally just got the lens on the camera. Its nicely built and the af is pretty fast. I mainly bought this to take some postraits of my twins that will be arriving soon and also for some band shots in low light. Now i can see how this would be good for portraits. But when i close the blinds to get a low light inside, like that you would expect ata gig, i bumo the iso up to 1600 and the only way to get enough light is with a shutter so slow that any movement will not be frozen. Am i doing something wrong?
thanks

puyjapin · Jul 25, 2009

also ive noticed that the shallow dof is very good for objects relatively close to the camera, however if i point it out the window at a person even wide open the areas beyond said person are still relatively sharp. why does this shallow dof only work with objects cloes to the lens?

Samanax · Jul 25, 2009

puyjapin said:
also ive noticed that the shallow dof is very good for objects relatively close to the camera, however if i point it out the window at a person even wide open the areas beyond said person are still relatively sharp. why does this shallow dof only work with objects cloes to the lens?

Nikonians Guide: Understanding Depth Of Field

Depth Of Field Tutorial

Examples For Understanding Depth Of Field

Tutorials: Depth Of Field

Happy Birthday

Markw · Jul 25, 2009

DOF is multifactorial. F/1.4 at 50mm and 1.5' from the subject is .01' of focal range (in focus range). The further the sunject is from the camera, the less shallow the DOF is. If you increase that distance to 15' and keep everything else the same, the range in focus is 1.46'. It increases with distance.

Check this out:
Online Depth of Field Calculator

Mark

Markw · Jul 25, 2009

And all links posted by Samanax who beat me out by a few minutes with a much better post, as usual.

Mark

puyjapin · Jul 25, 2009

how abt the light situation for bands, with a suitable shauuter speed?

Derrel · Jul 25, 2009

Well, when you close the blinds in your home, you are driving the light level downward,right? And so, the shutter speeds grow longer and longer as the light level drops. Are you putting the camera into Aperture Priority mode at something wide, like f/1.4 or f/1.8 or thereabouts? Or are you metering with the camera in Program mode?

Take heart; there's a a good chance that on band gigs there will be some spot lighting and/or floods that are actually quite a bit brighter than the light level in your dimmed-out living room. You might however, have to settle for a bit of motion blur on the most rapidly-moving parts of band scenes, like the drummer's hands and sticks, or band members head-bangin' actively. There are however, a lot of moments when a band member is actually somewhat still. Try and shoot what's called 'peak action'

Also, you should shoot in RAW mode for the best-possible recovery on bad exposures,and keep in mind that your light metering system might very well try and "lighten up" naturally dark scenes, which it would do by slowing down the shutter,so be aware that if you shoot in RAW mode and "cheat" a bit by underexposing in the camera, you can gain a stop or more of shutter speed (ie, cheat, and use a faster speed like 1/100 instead of 1/50) at f/1.8 or f/2 and correct a bit in the post-processing stage.

puyjapin · Jul 25, 2009

thanks, id be using raw yes and manual mod usually anless there is a better option?

puyjapin · Jul 25, 2009

so in terms of aperture would 1.4 be too wide for a portrait. ie would i lose detail beyond the eyes etc?

Derrel · Jul 25, 2009

Yes, f/1.4 is awfully wide for portraits shot at close range with a 50mm 1.4 lens on a crop-body camera. The depth of field is so,so shallow that it's very easy to misfocus or to have the subject move ever so slightly, thus blowing the focus. Depth of field at f/1.4 is very,very small at close ranges, and if there are two people in the shot, one of them will probably be out of focus.

It has always been difficult to focus precisely enough for f/1.4 lenses shot wide-open,and the closer you are, or the more the subjects are moving,the more difficult it is. I myself do not like the one eye sharp, back eye out of focus look that some people seem fascinated by; I think it makes more sense, and renders a prettier image, to have "most" of the head in focus in a portrait. Rather than shoot at f/1.4 or f/1.8 and having the nose tip slightly OOF, and one eye in focus, and the ears totally OOF, I prefer to stop down to a 'reasonably fast' aperture like f/3.2 or f/3.5, and to give myself a little bit of a DOF cushion to allow a bit of safety margin AND for a less-severe rendering than one would get with the lens wide open or nearly so.

puyjapin · Jul 26, 2009

so how about shooting bands in low light. surely the 1.4 aperture may be the only way? but if i use it wide open im not going to get much in focus?

dhilberg · Jul 26, 2009

It depends on how far you are from the stage. The closer the subject is to the lens, the more shallow the depth of field.

Only open up your aperture as far as you need it. If you need f/1.4, then use it, or you may end up missing the shots. I've never shot at a concert, but my guess is you'll need f/1.4.

DScience · Jul 26, 2009

don't just take everything people say as truth. If you are doing portraits in studio, or somewhere you need light. Thus a 1.4 isn't necessary. If you are taking pictures of live bands, unless you have tons of strobes you need a wide aperture. And for taking bands, you'll be at a good enough distance where you get plenty of focus in.

Check out Dustin Diaz's Flickr. He does amazing portraits and one of his main lenses is a 50mm 1.4g and he uses it wide open in low low light.