Single Focal Length Lens

[briansquibb]

Re: Single Focal Length Lens

Brian

I totally disagree with you regarding fast L series lenses.

If my wife ever found out that it was a myth and I didn't really need them .................... she would make my life unbearable! We must stick together and keep this myth alive.

Colin

For nature shots you need the fast lens as you are further away from the subject and the subjects are smaller ...... that is shown easily in the DOF Calculator.

[EOS_Jim]

Re: Single Focal Length Lens

Look at Macro lenses - Even at f16 when up close to your subject the depth of field is a matter of millimetres!

[Trevoreast]

Re: Single Focal Length Lens

OK lets dispel the mth that you need to shoot on a very wide open lens to get a blurred background. Blurred background is all about depth of field. Aperture is only one factor in the DOF.
I have been taking candid portraits all afternoon with my 70-200f4L. I had to shutdown the aperture to 4.5/5.6 for oblique portraits else the far eye was out of focus.

It's great when the coin drops, many people get "wide apertureitus" ie they've paid extra for wide aperture lens and they're damm well going to shoot wide open to get their money's worth.
That's probably why you see do many "one eye soft" pics posted.

Athough well taken isolated head and head and shoulder shots with telephoto lenses tend to impress non photographers and beginners. It's only scratching the surface of the art of portraiture. Personally, I worry that by the time I'm as good as I want to be, I will be too old to carry my kit

Trev

[Nathaniel]

Re: Single Focal Length Lens

Hi Nathaniel, I'd say the 85 f1.8 is a much better lens than the 50f1.8.... :) Focus is faster and built better.

Jim, what I meant was that it was as sharp as the nifty fifty- definition wise. This could be my next buy for a prime lens,for portraits etc, on my cropped bodies.

[Trevoreast]

Re: Single Focal Length Lens

Yeah go for it Nathaniel, £299 New from most reputable suppliers, you can't go wrong !
Trev

[collywobbles]

Re: Single Focal Length Lens

Nobody has mentioned the 50mm f/1.4 ( actually sharper than the f/1.2 )
85mmf/1.2 & 135mm f/2.0 extremely sharp.
85mm f/1.8 almost as good as 100mm f/2.0
My choice for indoor work (bands etc.) on F/F would be the 50mm f/1.4 - MUCH cheaper than the 1.2, performs better and only half a stop slower!

[EOS_Jim]

Re: Single Focal Length Lens

Jim, what I meant was that it was as sharp as the nifty fifty- definition wise. This could be my next buy for a prime lens,for portraits etc, on my cropped bodies.

i think my 85 may be sharper too especially wide open but both are good - certainly not knocking the nifty. On a crop body the 85 is long - too long for most indoor portraits of anything wider than a head and shoulders.

The new Sigma 85 f1.4 is creating some interest

[DrJon]

Re: Single Focal Length Lens

Sometimes you only want part of the head (usually the eyes) in sharp focus, although in my case I was talking about f2.8 on a 70-200, and at the longer end of that you are some way away. My point is f2.8 is useful for portraits but I have doubts about anything faster except for when you are after something special.

From the DoF page linked earlier in the thread:
5D2:
200mm f2.8 10yds DoF = 14"
135mm f2.8 6yds = 11"
100mm f2.8 4yds = 9" (although I'd say 4", see my post linked below)
However that's with a CoF for printing a non-cropped image, not for being optimal (see a very long and boring post I did a while back http://www.eos-magazine-forum.com/sh...ll=1#post36356).
Plus it's not like it's blurry 6" outside the DoF, just not sharp.
If you want the hair blurry behind the face you'll have to work at it a bit.

Oh, sorry, Colin, for the pro look with the eyes sharp and the hair blurry you need at least an 85mm f1.2 (which the page says is 3" at 10' on a 1.3x crop camera, but I'm not sure I agree) - anyway the 50mm f1.2 is nothing like a good enough lens for the money and I focus manually when drunk faster than the 85mm f1.2 (I'd probably bet money on that). BUT 300mm f2.8 is 4" at 37', so you really NEED one of those :-)

John

[briansquibb]

Re: Single Focal Length Lens

For portraits on the 5D you cannot beat the 135f2L

again

[DrJon]

Re: Single Focal Length Lens

I believe Canon claim the 85/1.2 is their best portrait lens. I would certainly say it's 100% the best lens to put on a 5DII before taking its portrait!!!
(Found an example of that... I kinda want an 85/1.2 just to photograph cameras with it attached to them!) http://www.flickr.com/photos/jean-maurice/3395186987/
I'll stick to the 70-200/2.8 II.
I think the 135/2 is fine if you have the space to get far enough away.
BTW photodo suggest the 70-200 II at 135/2.8 is as sharp as the 135/2 at 2.8, which surprised me considering how highly people seem to rate the 135/2.
(70-200 centre/border/extreme @ 135/2.8 is 3454/3124/2954 vs. 135/2 @2.8 3467/2982/2919, the 85/1.2 is scary sharp in the centre at 2.8 but noticeably not as good as the preceding 2 anywhere else, again according to photodo's FF tests.)
I suspect the 135/2 is a bit better out-of-focus than the 70-200, but I'll take the zoom and 4-stop stabiliser personally (others may prefer the 135's compactness though).
John

[briansquibb]

Re: Single Focal Length Lens

I suspect the 135/2 is a bit better out-of-focus than the 70-200, but I'll take the zoom and 4-stop stabiliser personally (others may prefer the 135's compactness though).
John

....brighter viewfinder
...and less than half the price too

[DrJon]

Re: Single Focal Length Lens

£900 vs £1800, the man has a point, but zoom, stabiliser and pretty much as sharp as a bunch of primes (all in one lens) works for me... I'm completely happy that people might disagree with me though, that's what a forum is for, letting people see a range of views... I'm just saying what I think and throwing in some factoids from others (are there real facts in all this, hmmm...) here and there...

[briansquibb]

Re: Single Focal Length Lens

Bad news if you are shooting at less than 1/125 with a 5DII so is the IS necessary? ..... as Colin C says the zoom is in your feet - 2 strides forward makes it a 50, 2 strides back makes a 200 (well approx)

Mind you I was shooting yesterday with my £400 70-200f4 so perhaps I should have gone with the cheaper option

[DrJon]

Re: Single Focal Length Lens

Personally I think IS on short telephotos is very useful, as they magnify all your movement. Plus IS allows lower ISOs on low-movement subjects in poor light (or outdoors at this time of year, as it is known), which gives less noise and more dynamic range (I certainly have a bunch of good shots taken at less than 1/125, where N/DR were important to me and there wasn't much/any subject movement). Also while you can sometimes step closer (not always though - I was shooting Southend Pier from a hill a while back and 200mm was useful) but you can't always step through a wall if 135 proves too long indoors.

I'd probably shoot a non-IS 135 at well over 1/125 if I was after a really sharp shot, and that's without allowing for subject movement (the 1/focal length "rule" isn't perfect, IMHO).

Oh, and before I forget, reasons not to get the 70-200 - it's expensive, big, heavy and white, so not that subtle and people can think you've got a telescope on your camera. Also the 70-200 f4 IS is a stonking lens, and a nice mug, but sometimes f4 is too slow or too much DoF, so swings and roundabouts.

I'm not saying buy lens X over lens Y, just explaining the reasons I did, plus some other observations, in case of interest to the OP.

[briansquibb]

Re: Single Focal Length Lens

IS allows lower ISOs on low-movement subjects in poor light (or outdoors at this time of year, as it is known), which gives less noise and more dynamic range. Also while you can sometimes step closer (not always though - I was shooting Southend Pier from a hill a while back and 200mm was useful) but you can't always step through a wall if 135 proves too long indoors.

I'd probably shoot a 135 at well over 1/125 if I was after a really sharp shot, and that's without allowing for subject movement (the 1/focal length "rule" isn't perfect, IMHO).

.

I think the discussion was about a lens for portraits?

If I go for full length portraits I use the 24-105. However I tend to go for head and head/shoulders most of the time.

For landscapes I am keen on the 17-40f4, 200 f2.8 and 100-400. On low light days I plump for flash assist