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occifer nick
17-07-2011, 9:55am
I know some people are going to look at this post and think, "this has nothing to do with the title and that was 2 mins of my life I won't get back!" sorry to those people ;) but for the ones still reading I'm not that familiar with Primes and wondering what the difference is.

I have read recently that a prime lens is a fixed focal length say 50mm, 28mm, 200mm etc does that apply to all fixed focal length lenses? I have the 60mm f/2.8 D and have been reading about the new 50mm f/1.8G that has great bokeh and is great as a portrait lens and then there is the 40mm on the horizon, apparently!

What I would like to know is; My 60mm is known as a macro lens and that's what I use it for, underwater macro actually is it the same as the 50mm besides the obvious difference in one being 1.8 and the 2.8, are they both a macro lens or is one specifically designed for macro and the other for portraits? I am asking because I was wondering if there is enough of a difference between the two for me to go out and purchase the 50mm for portraits? Or should I just use my 60mm macro and move a little bit further back than where I would stand if I had the 50mm? I understand that the 50mm 1.8 is going to be a lot better in low light and faster? Just slightly confused that's all lol

Anyway, hoping someone can clear this up a little bit for me?

Thank you in advance
:)

gqtuazon
17-07-2011, 10:01am
Hi I'm not an expert but your Nikon 60mm f2.8 is a sharp lens and will be an excellent lens for portrait (head and shoulders) typically. Macro are a little slower to focus but are sharp since they are more precise. It may not give you a constant f2.8 especially if you move too close to the subject. If you fancy the 50mm, try the newer 50mm f1.8G version. It is much sharper than it's counterparts from Nikon. Hope this helps.

kiwi
17-07-2011, 10:03am
Primes are always fixed focal length 8mm, 50mm, 400mm etc. The alternative is a zoom, 24-70 etc

Some primes are designed to be able to focus very close, ie macro but for all intents and purposes otherwise operate as a normal lens through to infinity

So, your 60 micro is going to be great for portraits too, but of course you'd know that as you've probably already tried

occifer nick
17-07-2011, 10:15am
Actually to be honest kiwi I haven't yet as I have only used it underwater for macro purposes. So there would be no point in my buying the 50mm 1.8G then just for the lower light performance and wider angle if I already have the 60mm?
Thanks for the replies though guys much appreciated.

gqtuazon
17-07-2011, 10:28am
Actually to be honest kiwi I haven't yet as I have only used it underwater for macro purposes. So there would be no point in my buying the 50mm 1.8G then just for the lower light performance and wider angle if I already have the 60mm?
Thanks for the replies though guys much appreciated.

I wouldn't but I would suggest the 85mm f1.4 instead for better subject to background isolation if that appeals to you or the 35mm f1.8G for group photo and some various things for low light situation. Try your 60mm for portrait first to see how it works out with your shooting style.

kiwi
17-07-2011, 10:33am
Actually to be honest kiwi I haven't yet as I have only used it underwater for macro purposes. So there would be no point in my buying the 50mm 1.8G then just for the lower light performance and wider angle if I already have the 60mm?
Thanks for the replies though guys much appreciated.

There's quite a difference between 1.8 (or especially 1.4) compared to a 2.8, whether you need that extra stop or two really depends on what you are shooting

Tannin
17-07-2011, 7:46pm
Occifer, there is indeed a difference between a 50mm macro lens and a 50mm portrait lens.

Macro lenses have the ability to focus quite closely, but they usually have several other characteristics: a typical macro lens:

can focus closely enough to reproduce small objects at 1:1 or greater (i.e., the image on the film plane is the same size as or larger than the object being photographed)
is very sharp and tends to be optimised for sharpness as opposed to other desirable characteristics such as nice bokeh (something that you aim for in a portrait lens and probably prioritize over ultimate sharpness)
has a flat plane of focus. The "plane" of focus of a standard lens is actually part of a sphere. If you use a standard lens to photograph a flat object (like a document) using a shallow depth of field, the corners are out of focus relative to the centre. Most of the time this doesn't matter, but for macro work it can be important.
Has very low distortion. (Again, consider document copying.)
has a moderately fast maximum aperture (typically f/2.8) to provide a good, bright view of small objects through the viewfinder and assist with focus accuracy. Macro lenses do not usually aim to be faster than f/2.8 because it then becomes difficult or impossible to achieve some of the other desirable macro characteristics.
has a very fine-grained, slow-travel focus mechanism. Both auto and manual focus actions tend to be slow but very accurate.


A typical non-macro prime lens - a 50mm/1.4 for example - is optimised for speed and DOF control, and nice bokeh. It can focus fairly close, but (as we have just seen) doesn't have all the qualities we mostly look for in a macro lens. You can use a non-macro lens for close-up photography (but within clear limits and only up to a point), or use a macro lens for other, non-macro tasks (usually quite happily and without much in the way of limits). Portrait shooters wouldn't select a macro lens over something specialised like an 85/1.2, but for most other tasks, either lens is fine.

occifer nick
18-07-2011, 6:59am
Thanks for the detailed explanation Tony it certainly cleared up some questions. Thank you all for your input. Ausphotography is such a great place full of very knowledgeable and helpful people.
Regards
Nick

I @ M
18-07-2011, 7:12am
Nick, if you are after a bit wider angle of view on a DX body I will second gqtuazon's suggestion of the 35mm F/1.8. It is a beaut little lens that is sharp, has plenty of built in contrast and is relatively inexpensive. We have one that seems to be permanently attached to a DX body now. Your 60mm will work well for portraits and if you want to get into photographing people a lot then a slightly longer lens again will also be an advantage.