prime vs zoom composition

fwellers · Feb 22, 2009

I know there have been threads about prime vs zoom, and am aware of the usual discussions about optical qualities of each.
There is an article or two around that argues a beginner ( or maybe anyone ) would learn composition better by sticking with one or two prime lenses.
Basically the way I understand it, the argument is that by being forced to move your legs, and the camera, you learn more about composing pictures.
Also after using some different primes long enough, you get a real good sense of what focal lengths give you different perspectives.

Another argument that I don't fully understand has to do with the difference between zooming in on something vs moving closer. Something to do with the relationship between subject and backround , the advan0mtage going to moving instead of zooming.

Can we hear some discussion about these ideas ?

If possible I would like this thread to allow for the basic premise that the user will not be a professional that is in a "must get the shot" situation. In those cases the advantage of zoom is obvious, but for the personal hobby shooter who has time to get his images.
I have a 50mm prime I almost never use. Perhaps I should force myself to use it more.
Also do you think that for a Nikon D90 ( 1.5 crop ), a 35mm lense would be a better walkaround than a 50mm ?

Thanks!
Floyd

table1349 · Feb 22, 2009

Understanding Depth of Field in Photography

Overread · Feb 22, 2009

using a prime removes a level of choice from the shooting - that of what focal length do I use - since the prime is fixed. Now if you further remove the option of changing lenses you have only one choice.
Thus its easier to consider the composition of the shot because you are only considering composing it in a single focal lenght - a single viewpoint.

Now when you have a zoom you can get a lot of different focal lengths - and you have to choose only one! Not only that but you have to then choose the right composition for that focal range - that is a lot of options you have open to you. When you start it can be too many and you end up just blasting away and hoping!
It is my belief that with more shooting and more practice you will learn how best to react in these situations (you start to prioritise both techinical and compositional elements of the photo)

it does not really matter if you start with primes or zooms - you have to still get the experience and put in the pratice

fwellers · Feb 22, 2009

thankrs. DOF issues aren't what I was hoping to hear about. I mean yea I know that fast primes give greater DOF control, and that focal length also affects DOF.
for instance:
what would be the difference between zooming in on a subject so that it fills the frame, versus moving closer to the subject so that it fills the frame. I read that you would get a wider field of view by doing the latter. It would be more interesting of a shot, unless for some artistic reason you were trying to compress (distort ) the field by zooming.

fwellers · Feb 22, 2009

thanks Overead, that makes good sense to me. It does seem that maybe forcing myself to "narrow the choices" may simplify things enough to expose different nuances of composing the frame.

dxqcanada · Feb 22, 2009

Moving closer to a subject will increase it's magnification.

Changing focal lengths will also change field of view.

There are numerous doc's that talk about this ... like this one about Depth of Field and Focal Length

fwellers · Feb 22, 2009

I just found an excellent thread on this subject here:
Composing with prime vs zoom lens - FM Forums

some of the proponents of using primes to learn with were very convincing. I learned a lot from that thread.

The primary idea I took from it is that perspective ( what you see from where you are standing ), is the most important thing to get. Then you can decide what FOV you want to use to compose that perspective. Walking around with a fixed prime forces you to examine perspectives.

However I still don't quite get it. I think I'll get it better when I put my zoom in the drawer for a while.

Any idea of what is considered the best prime for a 1.5 crop cmos sensor ? I'm thinking 30mm ?

dxqcanada · Feb 22, 2009

Most shooters pickup a 50mm lens as it is the cheapest (and also has the advantage of being one of the brightest/fastest lenses you will find).

For 35mm film shooter's ... this is the standard lens.

For a 1.5x DSRL ... 30mm or 35mm would be close to the standard (50mm) field of view.

fwellers · Feb 22, 2009

thanks for confirming that Dxq. I guess I could've just done ( 50/1.5).

)

NateWagner · Feb 22, 2009

One thing to keep in mind though is that when you use a fixed focal length lens you are cutting down what you can do with your field of view. Meaning that if you want a certain background with the subject being a certain size you will need a certain focal length. you can with a different focal length lens you can choose either the background or the subject size (in the photo) but not both (unless you can move the subject I suppose).

dxqcanada · Feb 22, 2009

That's why you should have multiple fixed focal length lenses.

I had this 35mm film lens setup ...

28mm / 50mm / 135mm / 300mm ... (plus 90mm Macro)

NateWagner · Feb 22, 2009

oh sure, but he was asking about to start out with. I was merely saying that he won't be able to achieve exactly what he is wanting to achieve with regards to background etc. with one prime lens.

Beyond that, I would say that even with multiple primes you still have to make some concessions about composition due to focal length.

(not that it's a big problem in the least, it's just that both primes and zooms have their pro's and their cons, and one can start out equally as well with either.)

skieur · Feb 22, 2009

If you are on a boardwalk over a swamp, in a small boat on a jungle river, on a rocky look-out trail etc. it is not possible to use your legs to make up for the restrictions of prime lenses. I have made extensive use of a prime 2.8, 28mm and a 2.8 200mm lens and they make beautiful shots, but I have also spent a lot of time changing lenses because neither has perfectly fit the scene.

The bottom llne becomes do you spend your time getting the shot and composing it, or changing lenses to get the right focal length. You can miss a lot of shots while you are changing lenses. I currently spend more time with a wide angle to portrait telephoto/macro and a longer telephoto zoom than I do with fixed prime lenses.

skieur

fwellers · Feb 23, 2009

skieur said:
If you are on a boardwalk over a swamp, in a small boat on a jungle river, on a rocky look-out trail etc. it is not possible to use your legs to make up for the restrictions of prime lenses. I have made extensive use of a prime 2.8, 28mm and a 2.8 200mm lens and they make beautiful shots, but I have also spent a lot of time changing lenses because neither has perfectly fit the scene.

The bottom llne becomes do you spend your time getting the shot and composing it, or changing lenses to get the right focal length. You can miss a lot of shots while you are changing lenses. I currently spend more time with a wide angle to portrait telephoto/macro and a longer telephoto zoom than I do with fixed prime lenses.

skieur

Sure I get that. And with the apparently little difference in optical quality between many zooms and primes ( especially at pro level ), that makes a zoom the thing to have for most of the time. At least I think that would be the case.
However, for a beginner, I am becoming rapidly convinced that more can be learned, and bad habits can be avoided by forcing oneself to deal with a fixed focal length.

Also, isn't it true that in the situations you mentioned above, one could take the shot with the prime and then crop in for what you want in PP ? If the prime is sufficiently sharp, it probably wouldn't matter much. In effect isn't that what you're doing with a zoom anyway ? Cropping ?

Overread · Feb 23, 2009

true if your lens and camera have enough quality to them and your shooting and exposure are dead on you can crop shots to get the composition you want - however again its a compramise. You can only crop so far with a shot before you start to limit its uses - crop a shot a little and it can still make a good 8*10 print - crop a shot a lot and it might only make a postcard or online sized shot.