Why not just hold the shutter half way, re compose and press all the way ?
Focus lock and recomposition?
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Why not just hold the shutter half way, re compose and press all the way ?
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Or switch to back button focus - using the correct focus point press the back button and then the shutter button to take the shot. Forget recomposing unless you have to.
You can press both at almost the same time.
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Yes
this explains the issue well: http://en.wikipedia.org/wiki/Petzval_field_curvature
This hints at what I did, about modern lens designs
"Most current photographic lenses are designed to minimize field curvature"
Unfortunatally, anything a lens designer designer does to correct one issue, impacts on another
This covers off axis abbreviations - http://en.wikipedia.org/wiki/Curvature_of_field
They are joined at the hip
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Choosing the correct focussing point takes comparitivley a lot of time, and is a double PIA if the next shot is framed on the other side of the camera
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Update
I thought I would check this out again, using a fairly unscientific shot. I have 2 monitors and a couple of phones in my office. I lined them all up in the same plane, and had text based documents on the monitor screens
Using the first camera that come to hand, I shot a photo of the desk, focussing on the phone, using the central focus point. The phone being far right in the arrangement. I then recomposed the shot to make the phone far bottom right in the frame (as far into the corner of the frame as possible)
Camera D7000 - That's my little throw in the car walk about camera and happened to be on my desk
Lens Nikon DX AFS Nikkor 18-105, set to 18mm
F3.5 for good measure
Result
1. the phone on the RH bottom corner of the resultant image was very sharp
2. the monitor next to the phone was quite sharp
3. The monitor in-front of me was slightly blurry
4. I can see I need to clean my desk badly :-(
This is what I had expected, because
The OOF monitor was 1M in front of the lens, the phone I focussed on was about 1.6M from the lens
I repeat this a few times rearranging my desk. I realise with this lens, at 18mm f3.5 the field of what is in focus is NOT in a flat plane, and NOT on the curved plane 1.6 M away, but between the two, closer to the flat plane than the curved plane
This is a very extreme experiment. I am pushing the point, as I have used 1.6 and 1M focus points. In a real world shoot, I usually am dealing with a much much smaller percentage deviation from either the flat or curved plane, which is why it works for me
However I expect the results to be different from lens to lens and focal length to focal length
The result above is a testament to the modern lens designers skill, and the fact they now have super computers doing the maths. It could have been really really bad, the reality was that in fact it was pretty OK (and considering we are at the bad end of a cheap zoom which TBH isn't know to be a particularly great lens either). Back in the day when Petzval was doing his original work on designing out aberrations and field issues, he managed to correct one issue and introduce another. Now they are correcting a range of issues and barley impacting on others. I don't feel so bad about the amount of pincushion distortion the lens has now. The real advance has been the introduction of bespoke aspheric surfaces, which can be computer modelled and generated on CNC machines for testing without the need for major tooling
I thought I would check this out again, using a fairly unscientific shot. I have 2 monitors and a couple of phones in my office. I lined them all up in the same plane, and had text based documents on the monitor screens
Using the first camera that come to hand, I shot a photo of the desk, focussing on the phone, using the central focus point. The phone being far right in the arrangement. I then recomposed the shot to make the phone far bottom right in the frame (as far into the corner of the frame as possible)
Camera D7000 - That's my little throw in the car walk about camera and happened to be on my desk
Lens Nikon DX AFS Nikkor 18-105, set to 18mm
F3.5 for good measure
Result
1. the phone on the RH bottom corner of the resultant image was very sharp
2. the monitor next to the phone was quite sharp
3. The monitor in-front of me was slightly blurry
4. I can see I need to clean my desk badly :-(
This is what I had expected, because
The OOF monitor was 1M in front of the lens, the phone I focussed on was about 1.6M from the lens
I repeat this a few times rearranging my desk. I realise with this lens, at 18mm f3.5 the field of what is in focus is NOT in a flat plane, and NOT on the curved plane 1.6 M away, but between the two, closer to the flat plane than the curved plane
This is a very extreme experiment. I am pushing the point, as I have used 1.6 and 1M focus points. In a real world shoot, I usually am dealing with a much much smaller percentage deviation from either the flat or curved plane, which is why it works for me
However I expect the results to be different from lens to lens and focal length to focal length
The result above is a testament to the modern lens designers skill, and the fact they now have super computers doing the maths. It could have been really really bad, the reality was that in fact it was pretty OK (and considering we are at the bad end of a cheap zoom which TBH isn't know to be a particularly great lens either). Back in the day when Petzval was doing his original work on designing out aberrations and field issues, he managed to correct one issue and introduce another. Now they are correcting a range of issues and barley impacting on others. I don't feel so bad about the amount of pincushion distortion the lens has now. The real advance has been the introduction of bespoke aspheric surfaces, which can be computer modelled and generated on CNC machines for testing without the need for major tooling
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Really? Canon's wheel makes it very rapid and if you are shooting a particular style you will be in that area already.
Not saying it should be used for everything though.
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Phew! Glad you mentioned it.
I was in fact trying to stay away from entering this discussion but glad you mentioned it because quite honestly I prefer to use different focus points then focusing and recomposing.
With the 5D MKII for example all it takes is a push from the thumb and then another push on the next button and the center focus point gets selected in an instant. If you want a different one just rotate the wheel or use the cursor after the first thumb push.
Come on, you call this PIA?
And with the 7D still easier as it has so many focus points that you end up spoilt for choice.
Of course I understand that with the 5D MKII as the focus points are mostly centralised so if you want to focus on the subject and its further away from the cluster of the focus points then recomposing is the alternative. Hence my question if there were specific techniques to achieve a sharper focus.
Quite honestly you can't compare shots by experimenting with desktop telephones on different focus planes. Dial in f/1.2 or f/1.4 and if its a close up portrait you are left with choosing whether you want to recompose after focusing and losing that critical sharpness on one of the eyes if that's where you focused on or you focus and shoot without trying to even breathe to hope to nail the sharp focus.
But hey, again I have to reiterate, I am just a newbie so I could well be wrong
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And with nikons focus tracking all it takes is recomposing with the af button held and the focus point moves for you. Much easier
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Phew! Glad you mentioned it.
I was in fact trying to stay away from entering this discussion but glad you mentioned it because quite honestly I prefer to use different focus points then focusing and recomposing.
With the 5D MKII for example all it takes is a push from the thumb and then another push on the next button and the center focus point gets selected in an instant. If you want a different one just rotate the wheel or use the cursor after the first thumb push.
Come on, you call this PIA?
And with the 7D still easier as it has so many focus points that you end up spoilt for choice.
Of course I understand that with the 5D MKII as the focus points are mostly centralised so if you want to focus on the subject and its further away from the cluster of the focus points then recomposing is the alternative. Hence my question if there were specific techniques to achieve a sharper focus.
Quite honestly you can't compare shots by experimenting with desktop telephones on different focus planes. Dial in f/1.2 or f/1.4 and if its a close up portrait you are left with choosing whether you want to recompose after focusing and losing that critical sharpness on one of the eyes if that's where you focused on or you focus and shoot without trying to even breathe to hope to nail the sharp focus.
But hey, again I have to reiterate, I am just a newbie so I could well be wrong
It is If I am shooting calculators, pones and monitors!
I can do it with a 1.4 50mm lens if you want, I don't happen to be surrounded by willing models today
Note my comment about 1.6M and 1M... = 37.5% difference at F3.5 & just about OK
If compared this to a real shot, where maybe I am 5M away recomposing something to say the same plane right in front of me at 4M (3/4/5/ triangle) = 20% difference
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And with nikons focus tracking all it takes is recomposing with the af button held and the focus point moves for you. Much easier
If you shoot like that. All this discussion is good, but makes an assumption about shooting style and subject matter. What about where you slowly compose something on a tripod or in a studio for example
One type of shooting is quite manual
One type of shooting is more automated
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If you are this tight on DOF, forget recomposing, you need to clamp the sitters head first
When things are this tight, I pop the camera on manual focus, and move myself until it looks sharp. Alternatively, It is slowly set up on a tripod. I don't ever recall shooting real people like this though. I use more DOF. I have a 1.4 lens, I rarely go anywhere near the 1.4 end of it
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And with nikons focus tracking all it takes is recomposing with the af button held and the focus point moves for you. Much easier
Oooh that is so fantastic. Didn't know Nikons do that. Lucky you all Nikon users, would love that on my 5D MKII.
The 7D on Servo achieves the same thing though
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at 200mm at f/2.8 shooting heads I really like to nail the focus on the closest eye, and you would be surprised the keepers I get even shooting at low shutter speeds with my 70-200mm f/2.8 MKII.
And the fraction of shots I miss are due to sitter's movements like you mentioned yup. Very few shooter's errors. You just need to get to know your kit well and learn to get the best out of it
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Richard King said:
Why else do you bother with the expense and weight of f/1.4 or f/1.2 lenses if not to use them. Shooting people - even fast moving children in real world situations, without clamps is more then doable and done often by a great many photographers. No tripods either
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EOS_JD said:little expense and weight with a 50/1.4
Yep they're only 3 times the price of the f/1.8
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Richard King said:
It's not a pita if you set your camera up properly. Select wrap around in the menu and it's a doddle.
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boyfalldown said:
Three times the price of b****r all isn't much!
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The23rdman said:
Oh, you're talking Canon...
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The23rdman said:
Shall we compare say a 35 f/2 to a35 f/1.4. 3 times is still three times the amount and I'm sure you're well aware of the point being made. Why pay for f/1.4 if your not going to use it?
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My point exactly.I only have the 70-200 f/2.8 MKII at the moment but if I could afford I would add the 85mm f/1.2 in my arsenal too.
Most of my shots with the 70-200 are all at f/2.8 and I feel I could go wider still. And never needed to tie the sitter either
Never bothered with using any focus points other than the centre one, especially on the 550D (as the AF system isn't a touch on that of a 7D, 5D MKII etc).
I always focus and then recompose. I am yet to come across a situation where my focus point, exposure point and subject are three different things.
I imagine with a 1D-X using outer focus points won't be so bad but as far as I know the centre point is always the most powerful and accurate on any Canon AF camera and a lot of the time I don't have time to wait for the camera to hunt for focus. Also I'm not sure whether any other than the centre point can detect the AF assist beam from speedlights.
I always focus and then recompose. I am yet to come across a situation where my focus point, exposure point and subject are three different things.
I imagine with a 1D-X using outer focus points won't be so bad but as far as I know the centre point is always the most powerful and accurate on any Canon AF camera and a lot of the time I don't have time to wait for the camera to hunt for focus. Also I'm not sure whether any other than the centre point can detect the AF assist beam from speedlights.
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Easy
In a dark church on a bad day I need 1.4. That's my worst case scenario.
Here is my logic: Example - the Nikon 50mm AFS 1.4 works on both crop and full frame well, and is a cracking lens at reasonable apertures. Like cars, just because you can go 140MPH, doesn't mean you need to. My car will do 140MPH, but in reality, it means it is very comfy doing 70. If I brought a car that struggled to do 80, it would be a mare doing 70. Same principle with the lenses. Just because I have 1.4, 1.8, 2.8 lenses doesn't mean I need to permanently shoot at 1.4, 1.8 or 2.8. However a lens designed to perform well at 1.4, in my experience is absolutely stunning at 3.5. it has some headroom, and occasionally if i want to, i dip down into a wider apeture
Also
The 1.4 lens like most lenses is very good a few stops away from its wide open aperture. Out of choice, would you prefer to shoot at 3.5 on a lens where 3.5 was its max apeture, or 3.5, on a lens which can go to 1.4?
The point of having a few primes in the bag is to have better optics, better optics doesnt mean shooting with the lens at its limits
So do I want to shoot at 3.5 ish, and be very sharp on my 1.4 prime lens, or 5.6+ on my 2.8 or 3.5 zoom lenses?
In a dark church on a bad day I need 1.4. That's my worst case scenario.
Here is my logic: Example - the Nikon 50mm AFS 1.4 works on both crop and full frame well, and is a cracking lens at reasonable apertures. Like cars, just because you can go 140MPH, doesn't mean you need to. My car will do 140MPH, but in reality, it means it is very comfy doing 70. If I brought a car that struggled to do 80, it would be a mare doing 70. Same principle with the lenses. Just because I have 1.4, 1.8, 2.8 lenses doesn't mean I need to permanently shoot at 1.4, 1.8 or 2.8. However a lens designed to perform well at 1.4, in my experience is absolutely stunning at 3.5. it has some headroom, and occasionally if i want to, i dip down into a wider apeture
Also
The 1.4 lens like most lenses is very good a few stops away from its wide open aperture. Out of choice, would you prefer to shoot at 3.5 on a lens where 3.5 was its max apeture, or 3.5, on a lens which can go to 1.4?
The point of having a few primes in the bag is to have better optics, better optics doesnt mean shooting with the lens at its limits
So do I want to shoot at 3.5 ish, and be very sharp on my 1.4 prime lens, or 5.6+ on my 2.8 or 3.5 zoom lenses?
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I know that. I was responding to the phrase
"where you focused on or you focus and shoot without trying to even breathe to hope to nail the sharp focus."
What I don't get is the need to shoot with such a narrow DOF
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Richard King said:
I realised you don't get it - but some of us do & manage it without having to tie, clamp or otherwise restrain our subjects and we also know that the results can be very very good.
It's not about using them because its dark in church either - it seems unlikely that 2/3rds of a stop over much cheaper lenses makes much odds . Car analogies don't work either
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I can shoot these shots without clamping too, I just dont out of intention corner myself to a point where everything is technically on the edge, hoping my camera is picking up the pieces for me
Looking at this thread I can see 2 camps
On the one hand there is a way of shooting that hankers back to the film days, where you manually set your exposure (with a dial), you composed the shot and manually focused a camera (on the lens) to put whatever you wanted in the shot in focus
On the other hand, modern cameras offer AF, can set the exposure for you, and do auto everything, all from the shutter release
Essentially we are discussing how many of these settings do we ditch, and either separate out to other buttons, or go completely manual with
This is where shooting style is really important. Back in the film days, we had 1.2 lenses too, and we focused them manually, with the assistance of a focussing screen. However what we did more was get the focus about right and then use our eyes, and move ourselves for the final adjustment. Shooting back then was slower, more deliberate and you only knew if the shot was sharp when the film came back. The cost of developing meant you really worked at each shot
With modern cameras we have
- AF
- Auto ISO
- Auto Exposure
- A Plethora of exposure modes
- A plethora of exposure points
- Focus tracking
It is way to easy to spend so much time fighting with the camera to make it do what we want, we kind of miss the obvious
- A lens only focuses at the distance you or the camera chooses. Extra AF points doesn’t actually really mean anything once the shutter is pressed
- The photograph is only shot at one F stop and shutter speed & ISO
So all things being considered, once you get your photographer thinking cap on, you can effectively ditch a lot of the automatic calculations your camera silently tries to foist on you, and get control of your camera back. That’s why I shoot the way I do…
I generally look at a shot and I decide
– what approx shutter speed / aperture do I want
– I determine – is aperture more important than shutter speed
– I meter accordingly, intelligently looking at the scene, and choosing a point to meter off
– I have now decided my aperture and shutter speed and ISO
– I then decide – ow is this going to be focussed – what is OK in focus and what isn’t. I focus on the primary subject (or whatever) and then recompose. I then do a DOF preview if I have time
– I now am set up for taking the shot. The above might have taken ½ a second to 30 seconds depending on the subject and urgency
– I now wait for the shot to come to me and shoot
I feel the difference in the way I generally shoot, and the way a lot of more modern shooters shoot is that I am not relying on my camera to make creative decisions for me, or to be fairer – to allow my camera to destroy my creative decisions by over riding what I have set up
Now I am not a Neanderthal, I can still switch on all of the auto functions on my cameras one by one, and I do. The point being that I do this for a reason, and I still feel somewhat in control
This brings me onto shooting at 1.4. It seems to me this has become a style. For example if we actually thought about it, we would realise that a different lens at a different shooting distance will give you the same DOF that you get at 1.4 on a 50mm. Now you have a creative choice – say shoot with one lens at f4.5 or another at 1.4. If you know your lenses backwards, you can potentially get a sharper cleaner shot with less aberrations
The 1.4 issue is interesting. Everyone says wedding photographers need fast glass, and a 1.4 lens is an obvious choice. However nowadays we are actually trading off the following against eachother
- DOF (Potentially isolating the subject and loosing context, or just screwingthe shot up)
- ISO (NOISE)
- Adding extra lighting (takes time and effort and may not be possible)
- Abberations (which are more prevelant on a wide open lens)
- Diffaction (at the other end of the scale)
So as a photographer I see that I have a lot of things to keep between the rails, and often I trade DOF for ISO for example. Ultimatally, in practice, this means whilst I have some latitude on ISO, some on Apeture, I don’t go for the extreme setting in either direction. And that increases the chance of a nice clean sharp shot free from noise and abberations. I wholeheartedly agree that if you want to shoot fast go-cart racing in the dark with no flash, you are going to be making some major compromise, and that you will gladly take any help your camera gives you regarding focus lock etc.. However for the majority of my work, I can be slower, more measured and thoughtful about each shot, and each set of compromises I make
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I'm sure you don't mean that reply to be quite as patronising as it actually reads, but just for the avoidance of doubt there are also alot of photographers who will use modern tools to the fullest without letting the camera make creative designs for them, but take advantage of the full range of tools they are paying for.
For example, modern AF systems are generally so good now I can't understand for the life of me why you'd want to use MF outside of a few very specific situations. At the same time I'll use manual exposure (you know, the one so you can go down the pub and drink warm beer with all the 'real' photographers, and it makes me a real man)but if I thought about it a little more I may use exposure comp instead. The only reason I don't is cause I can achieve exactly the same thing faster using manual.
So, TBH your 2 camps idea is wrong. Theres at least 3. Yes you're absolutely right, there are a lot of photographers who'll just use auto mode, and theres also the stuck in do everything manually cause it makes them a creative and better photographer camp somehow, but theres also a 3rd camp, photographers who understand and can use the new technology to suit what they want, not letting the camera lead them
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It wasnt supposed to be patronising at all, just an observation
I am probably between camps 2 & 3
On modern cameras, the focussing screens are so poor or non existent, you pretty much have to use AF to actually pick out your point. the bit I get my knickers in a twist over is when the camera suddenly starts changing the focusing for me, once it is selected
It isn't about "real photographers" and "everyone else" either, It probably is more about my own shortcomings with most modern cameras. FWIW I get on better with pro cameras with less features than I do with the Prosumer cameras
In saying that, modern camera are sometimes counter intuitive at some things. Example... If you use Auto ISO, you imagine it will switch itself off when you click the camera over to Manual (for example), it doesn't half throw you when it keeps changing it!
What I found is that if we look at AF for example cameras appear to me to be a bit OTT nowadays, and I find the more automatic modes get in the way rather then help. Other photographers probably have a totally different experience of this. Out of the box I have a camera with 50 odd focus points, and it chooses the thing that the camera thinks is closest to focus on. As you shoot, the points flick about and TBH I find that distracting. So I tamed it down and down to the point where the camera does what I want
I do get that there are circumstances where focus tracking and the like is super useful, but I don't really shoot that sort of stuff. It will be interesting to hear if the Sports photographers use it, and how effective it is
A lot of features on modern cameras are so clever that the designers deserve medals, but this has made cameras so complicated, that in real time, doing the job, you have to leave them to one side because a minute of button pushing & menu navigating means you miss the shot
Interesting debate
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:bang::bang::bang:
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Im going to stop reading this thread now.. My head hurts
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I think those who don't get it about shooting at widest aperture possible should really look at some examples of what it can achieve. Timothy Allen being one such photographer, have a look at his images, this for example, shot at f/1.2 even though he didn't need to. Look at his shutter speed... http://www.facebook.com/photo.php?fbid=236235236441676&set=a.160490384016162.38314.153133734751827&type=1&theater
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I agree with you, that's a stunning shot. However look at the rest of his shots. They are all crackers, and he is exploring all of the apertures on his lenses
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You could probably stand off with a 200 or 400mm/2.8 lens at f/4 and achieve almost the same without the inherent risks of being wide open..
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Let me see if I got this correctly, are you trying to say that when an image exudes a photographic impact due to the fact that it was shot wide open the very same image can be shot at one stop closed aperture and achieve almost the same impact?
Well, I may be a newbie around these fields but I suspect there is something wrong in what you are saying. Surely there are many who buy a lens that can go extremely wide on aperture mainly for its impact rather than just to allow them to use on low lighting situations
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Look at this
http://www.dofmaster.com/dofjs.html
What you need to figure is the typical distance(s) you are working at for a given pair of lens(s). Keep all other variables the same (choose a camera and stick with it)
(For a canon 7D) Compare say A 300mm lens at 40 feet F3.2 to say a 50mm 1.4 at 10 feet
300mm @ F3.2 @ 40 feet
Depth of field
Near limit 39.7 ft
Far limit 40.3 ft
Total 0.64 ft
In front of subject 0.32 ft (50%)
Behind subject 0.32 ft (50%)
50mm @ F1.4 @ 10 feet
Near limit 9.69 ft
Far limit 10.3 ft
Total 0.65 ft
In front of subject 0.31 ft (48%)
Behind subject 0.33 ft (52%)
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There are times when you are positively Zen-like Ade.
Not very often, but there are times!
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There are times when you are positively Zen-like Ade.
Not very often, but there are times!
I think there is a compliment in there, or just a load of sarcastic stuff.................
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Yup, subject to the constraints of field of view.
As Ade sort of points out, the perspective will flatten using a telephoto (also read distance) but the relative difference between an 85mm and a 200mm isn't necessarily as great as you'd think.