Focus/compose with fast lenses newbie

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jasperamsterdam

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Hi all,
just bought a m8. After owning a m6 for a few months i'm picking up my rf skills. I was thinking o buying a real fast lens to maximise low light capibilties, minimise DOF and enjoy quality of leica glass wide open.

At the moment i only have the 28 elmarit and even with this 2.8 lens i found focus and recompose resulting in a lot of off focus shots. Its easy math you lose point of focus if you rotate the camera after focussing but maybe its digital and 100% view that made it so obvious for me.

Does anyone have tips, or are all the luxes @1.4 and M's made for photos with subject in dead center?
 
Practice.

There is no other answer. You soon learn to focus and move the camera after focusing.

Actually, there is a bit more of an answer. Ultra-shallow d-o-f very, very seldom works. Of course it can; but far more often, there is a nauseous display of blurry nothing, behind a small, sharp excuse for taking the picture. It's a fad at the moment, just as deliberate camera shake was a fad a decade ago; but unless the shallow d-o-f is a 'natural' part of the composition -- which it very seldom is in good light with an ND filter on a Noctilux -- it is all too often a pointless affectation. This from someone who has tried it and reckons it did his photography no favours at all.

Cheers,

R.
 
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I guess it's one of the things were an SLR with its instant depth-of-field preview in the viewfinder actually has an advantage.
 
Best advise I can give is lots of practise. I can now shoot confidently at f2.8 pretty much all the time. Anything below that gets way trickier esp low light. At 1.4 and slow shutter speeds, the object pretty much have to be reasonably still.

@f1.4
2920251480_cb0ec99768.jpg


@ f1.4
3975913993_2933d4f4ef.jpg


@ f2 or 1.8
3968533266_0b17976411.jpg


@ f2
3468608685_f92b5171bb.jpg
 
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jasperamsterdam said:
Its easy math you lose point of focus if you rotate the camera after focussing but maybe its digital and 100% view that made it so obvious for me.

Does anyone have tips, or are all the luxes @1.4 and M's made for photos with subject in dead center?
Click to expand...

It's easy to show that it's not a problem. Let's pick a 28/2.0, for example, which on the M8 has a diagonal FOV of 60 degrees.

Say you do 1/3rd composition, with 1m focus distance (almost worst case). Then the error is 1m * (1 - cos(60/6)) = 1.5cm. The DOF of a 28/2 wide open at 1m on the M8 is 11cm total, 5cm in front and 6cm behind subject, which more than covers the error.

Unless you have a superfast normal like the 35/1.2 or 50/1.0 don't worry about it. Focus errors are either due to equipment problems or other operator problems.

Cheers,

Roland.
 
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Actually with 1/3 composition you're being rather generous, because you limit your angular error to 1/3 of the maximum, and since the cosine isn't linear the error gets progressively worse. In your 28/2.0 example, the worst case is if your in-focus subject is in a corner; you get as an error 1m * (1-cos(60/2)) = 13.4 cm. So while your angle increases by a factor of three, your error increases almost by a factor of ten and falls well outside the DOF. In other words, if your focus subject is near the borders of the frame, it is a problem.

On 35mm it's even more of a problem, because on a cropped sensor the field of view is smaller (hence smaller angles), and because crop lenses have more DOF if compared to lenses showing equivalent field of view on 35mm.

Philipp
 
I agree, Philipp.

Still the OP's 28/2.8 should cover even the most extreme corner error from 2m or so onwards ? I still doubt what he sees is due to recomposition.

And, since he seems to be new to RFs I recommend to have his gear checked.

If you look at boy_lay's example's and mine below, around 1/3rd is rather typical though - no surprises there of course.

With a 35/1.4 on film, wide open and near close focus (.7 - 1. m).

562276508_kZ2V3-O.jpg


477754229_zh6EQ-O.jpg


562276556_nrWMC-O.jpg


621564381_C2a9X-XL.jpg


And, much more extreme as you said, a 28/1.9 on film:

195928145_fpnwG-X2-1.jpg
 
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I agree - while recomposition can be a problem in extreme circumstances, it's probably also makes a tempting universal source of focus errors even where it actually isn't a problem. The vast majority of shots probably has its subjects within 1/2 or 1/3 from the center. Rangefinder focusing in general needs getting used to, and if the errors are consistent it may well be a gear problem as well.
 
ferider said:
It's easy to show that it's not a problem. Let's pick a 28/2.0, for example, which on the M8 has a diagonal FOV of 60 degrees.

Say you do 1/3rd composition, with 1m focus distance (almost worst case). Then the error is 1m * (1 - cos(60/6)) = 1.5cm. The DOF of a 28/2 wide open at 1m on the M8 is 11cm total, 5cm in front and 6cm behind subject, which more than covers the error.

Unless you have a superfast normal like the 35/1.2 or 50/1.0 don't worry about it. Focus errors are either due to equipment problems or other operator problems.

Cheers,

Roland.
Click to expand...

Roland and I have disagreed on this point in an earlier
thread on the same subject. I often compose with my
subject close and well off-center. If you are critical
about focus, you cannot swing the camera after focusing
to recompose. I shoot only people. If you focus on eyes
and then swing the camera to put the person on the edge
of the frame, the hair around his ears will be in sharp
focus, and the eyes will be just soft enough to ruin the
photograph.

The only solution is one suggested by another photographer
here: Focus the camera, then slide the camera sideways
to recompose so that the subject remains in the focal plane.
Do it a few times and it will become second-nature.
 
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Al Kaplan said:
When you slide the camera sideways you change the relationship between the subject and any background features in the picture.
Click to expand...

To be clear, I first compose the frame the way I want
it, taking the background into account; then I slide to
put the RF dot on my subject, and focus; then I slide
back to my original spot, and shoot. Then the frame
looks as I intend it and I have a fighting chance of laying
focus with the precision I demand in my photographs.

The more I do this, the more I appreciate my Rolleiflexes.
 
Thank you all for your opinions!
There seems to be alot of different ways at looking at the issue, from
Ultra-shallow d-o-f very, very seldom works
Click to expand...
to
It's easy to show that it's not a problem.
Click to expand...
to
while recomposition can be a problem in extreme circumstances, it's probably also makes a tempting universal source of focus errors even where it actually isn't a problem
Click to expand...
to
Focus the camera, then slide the camera sideways
to recompose so that the subject remains in the focal plane.
Click to expand...
to
Good lighting, dynamic composition, and the exact point of focus in many cases isn't all that important.
Click to expand...

I guess i already knew that there is no easy answer, seems it's up to me and my technique or shoot wide open with the subject near the center. I'll start practising on the slide!

Must say extra focuspoints in SLR's seem to give an advantage, which is a shame for the wonderfull fast leica glass.
 
the use of small DOF

the use of small DOF

I must say i feel what Roger is saying, shallow DOF is sometimes a bit overused, and the danger of becoming "gimmicky" is around the corner.

You should always be critical as and artist and judge if it adds to the photo.

There is no way i can back this up statisticly, but say of "all the best, most important, beautifull (blablabla) photo's in the world, only a very small percentage is taken with razorthin DOF.

That is not to say you'd never use that Noctilux or Lux wide open ofcourse.
 
jasperamsterdam said:
I must say i feel what Roger is saying, shallow DOF is sometimes a bit overused, and the danger of becoming "gimmicky" is around the corner.

You should always be critical as and artist and judge if it adds to the photo.

There is no way i can back this up statisticly, but say of "all the best, most important, beautifull (blablabla) photo's in the world, only a very small percentage is taken with razorthin DOF.

That is not to say you'd never use that Noctilux or Lux wide open ofcourse.
Click to expand...

Exactly.

Cheers,

R.
 
jasperamsterdam said:
I must say i feel what Roger is saying, shallow DOF is sometimes a bit overused, and the danger of becoming "gimmicky" is around the corner.

You should always be critical as and artist and judge if it adds to the photo.

There is no way i can back this up statisticly, but say of "all the best, most important, beautifull (blablabla) photo's in the world, only a very small percentage is taken with razorthin DOF.

That is not to say you'd never use that Noctilux or Lux wide open ofcourse.
Click to expand...

Most of the images I like the best, are taken with a thin or razorthin DoF, and I like that look. Everything can be looked upon as a gimmick or labeled a gimmick by someone that lacks real arguments against something 🙂 BW is just a gimmick for those that lack the skill of composing in color, color is just a gimmick for those who lack the skill of composing in BW, tilt&shift is just a gimmick, street photography is a gimmick... seriously, get over yourselves, you don't like it, fine, others do.
 
jasperamsterdam said:
..says the guy who just ordered a canon 50 1.2 creammachine...😉
Click to expand...

It's a fun lens -- but I gave mine away because I didn't like it enough wide open to justify it next to a C-Sonnar, 1/2 stop slower. Or at f/22, where image quality is dire. But at f/5.6 to f/11 it's astonishingly good, and at f/1.2, it's better than anything that isn't f/1.2 or faster. To a considerable extent, it is a 'do it all' lens, with all the speed you normally need up to f/1.4 or maybe f/2, and that final desperate half stop when you want zero d-o-f or ultimate speed.

I must say that as far as I am concerned, putting ND filters on ultra-fast lenses to allow you to shoot at wide apertures in good light is almost never successful. As soon as you can use the full aperture (or just a very wide aperture) at a sane shutter speed (probably not 1/4000 or higher) there is a much better chance of shallow d-o-f being an integral part of the picture: as you say 'judging as an artist'.

The reason I didn't write 'for me' in an earlier post is that I've only ever taken a few pictures I really like with ultra-shallow d-o-f (where my favourite is inclined to be the 135/2.8, because I had to give the Noctilux back) and from all the other pics I've seen by other photographers, very few have enjoyed much more success with wafer-thin d-o-f than I. As I say, some do, but not many; and as you say, how many truly great pictures do you see taken with razor-thin d-o-f?

Of course there's always Sturgeon's Law, but from all I've ever seen, for ultra-thin d-o-f the success rate is probably near 1% or even 0.1% than the 10% implied by Sturgeon's Law ("Ninety per cent of EVERYTHING is cr@p.")

Of course there are those who will disagree.

Cheers,

R.
 
ulrikft said:
Most of the images I like the best, are taken with a thin or razorthin DoF, and I like that look. Everything can be looked upon as a gimmick or labeled a gimmick by someone that lacks real arguments against something 🙂 BW is just a gimmick for those that lack the skill of composing in color, color is just a gimmick for those who lack the skill of composing in BW, tilt&shift is just a gimmick, street photography is a gimmick... seriously, get over yourselves, you don't like it, fine, others do.
Click to expand...

Nothing is a gimmick if it is used well. Anything can be a gimmick if if it is picked up by those who can't use it and can't take a decent picture of any kind. A while back, this was deliberate camera shake. Right now, it's a toss-up between HDR and ultra-thin d-o-f.

Sorry if you don't find my argument 'real', but there's a reason why the word gimmick exists, and to pretend that nothing is ever a gimmick is even less of a real argument. All I said was that it is very seldom successful. This does leave the possibility that it can be. You like it, fine: others don't. What's to 'get over'?

Cheers,

R.
 
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