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Author Topic: Interesting article on sample variations  (Read 10911 times)

Ray

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Interesting article on sample variations
« Reply #40 on: March 21, 2010, 07:30:43 pm »

Quote from: Rob C
I despair of me Ray; if such did become the norm it would be but one more device I would have to learn to override in my attempts at getting back to a digital F3.

Rob C

Rob,
Surely by now you have worked out all the functions of those 32 buttons and dials on the D700, and found that their use has become second nature to you!  

Autofocus bracketing seems a great idea to me, not only to ensure that one of your 5 or 7 or 9 shots is precisely focussed on the feathered bird's left pupil, but also in order to extend the DoF range (by merging the 9 shots using a program like Helicon Focus) to get the effect of a razor sharp pin-hole camera.

This is progress, no?
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Rob C

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Interesting article on sample variations
« Reply #41 on: March 22, 2010, 05:50:35 am »

Quote from: Ray
Rob,
Surely by now you have worked out all the functions of those 32 buttons and dials on the D700, and found that their use has become second nature to you!  

Autofocus bracketing seems a great idea to me, not only to ensure that one of your 5 or 7 or 9 shots is precisely focussed on the feathered bird's left pupil, but also in order to extend the DoF range (by merging the 9 shots using a program like Helicon Focus) to get the effect of a razor sharp pin-hole camera.

This is progress, no?




But Ray, why would I do that when I don't need to? Why would I seek to complicate the otherwise very simple process of making a piccy? Can anyone really say that shooting a film camera was difficult, more complex than working a digital one? The very fact that it is - so far - possible to cut out all the bells, whistles and fantasy buttons is a veritable blessing I would hate to see vanish forever under the mists of psuedo-technological advances. The one and only benefit I see to the digital camera is this: the histogram. In fact, even that is somewhat doubtful because prior to digital image making, all you needed was a Weston that you could buy for peanuts and never was the need for the then non-existent histogram even imagined or felt.

We have thrown the poor old baby out with the suds and substituted a very simple process by one far more complex if you wanna get it right!

This is progress, no? No. It is the enforced swapping of a perfectly good, perfected system for a new one that came as much of a culture and business shock to the established camera makers as to Kodak who played Dr Frankenstein, in the process effing up huge numbers of established photographic businesses. Some people on this site keep saying how digital has lowered the cost of entry into the business of photography. Nonsense! You have to include all of the associated digital costs when you make claims like that, not just draw a line at the cameras. I certainly never had a computer when I was working, never needed one, never imagined I'd even be interested in one which, to be honest, I still am not. It is simply a necessary evil without which I couldn't communicate in this contemporary world since nobody remembers how to use the telephone, and writing is simply unheard of apart from the card at Christmas. No wonder the number of illiterates is forever growing, punctuation has become a mystery and eloquence suspect, the butt of accusations of elitism which also, by the way, is a word utterly misunderstood.

So all in all, the fewer 'functions' the better for me!

Rob C
« Last Edit: March 22, 2010, 05:52:02 am by Rob C »
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Ray

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Interesting article on sample variations
« Reply #42 on: March 22, 2010, 07:40:06 am »

Quote from: Rob C
But Ray, why would I do that when I don't need to? Why would I seek to complicate the otherwise very simple process of making a piccy? Can anyone really say that shooting a film camera was difficult, more complex than working a digital one?

Rob C


Absolutely yes! I see that you freed yourself of the complexity and mess of wet darkroom processing when you were once earning a crust as a professional photographer. Some of us, amateurs, struggle with the entire processing chain from pressing the shutter to making the print, and we work to our own standards. We are our own most difficult and exacting client.

Quote
The very fact that it is - so far - possible to cut out all the bells, whistles and fantasy buttons is a veritable blessing I would hate to see vanish forever under the mists of psuedo-technological advances. The one and only benefit I see to the digital camera is this: the histogram. In fact, even that is somewhat doubtful because prior to digital image making, all you needed was a Weston that you could buy for peanuts and never was the need for the then non-existent histogram even imagined or felt.

If you don't need a feature, don't select it or activate it. No need to cut it out. I always preferred 'through-the-lens' metering to an external light meter, even 40 years ago. The only problem I find, sometimes with the myriad of buttons and options, is how to activate a feature I want.


Quote
This is progress, no? No. It is the enforced swapping of a perfectly good, perfected system for a new one that came as much of a culture and business shock to the established camera makers as to Kodak who played Dr Frankenstein, in the process effing up huge numbers of established photographic businesses. Some people on this site keep saying how digital has lowered the cost of entry into the business of photography. Nonsense! You have to include all of the associated digital costs when you make claims like that, not just draw a line at the cameras. I certainly never had a computer when I was working, never needed one, never imagined I'd even be interested in one which, to be honest, I still am not. It is simply a necessary evil without which I couldn't communicate in this contemporary world since nobody remembers how to use the telephone, and writing is simply unheard of apart from the card at Christmas. No wonder the number of illiterates is forever growing, punctuation has become a mystery and eloquence suspect, the butt of accusations of elitism which also, by the way, is a word utterly misunderstood.

Rob, you're beginning to sound like the quintessential Luddite of photography   .
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Rob C

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Interesting article on sample variations
« Reply #43 on: March 22, 2010, 11:15:57 am »

[quote name='Ray' date='Mar 22 2010, 12:40 PM' post='354854']
1.   Absolutely yes! I see that you freed yourself of the complexity and mess of wet darkroom processing when you were once earning a crust as a professional photographer. Some of us, amateurs, struggle with the entire processing chain from pressing the shutter to making the print, and we work to our own standards. We are our own most difficult and exacting client.

Reply 1.   Freed no; living in an apartment in a water-challenged country I couldn't keep it going in all good faith. I had air-con installed in the office/darkroom, and then I had a heart attack installed and I could no longer risk pouring 20x16 dishes of chemicals back into winchesters when all that lay as security between my new, weaker self and the fitted carpets was a towel! I have never found anything to match a WSG 2D print well glazed! (Something St Ansel also discovered when he gave up textures.) A Hahne matt print inside a crystal archival envelope comes close, but remove the thing from the envelope and it is dull and flat again. All a bitter irony when I realise that I ended up being the guy running the colour lab in the industrial photo unit I started in as a trainee six years earlier. Oh well, the commercial world did beckon after that...

2.   If you don't need a feature, don't select it or activate it. No need to cut it out. I always preferred 'through-the-lens' metering to an external light meter, even 40 years ago. The only problem I find, sometimes with the myriad of buttons and options, is how to activate a feature I want.

Reply 2.   Never did like ttl metering, even though my F2 was a Photomic; never used that feature and relied on the Weston with Invercone.

3.   Rob, you're beginning to sound like the quintessential Luddite of photography.

Reply 3.   For Luddite, substitute practical realist.

But to each his own!

;- )

Rob C  

telyt

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Interesting article on sample variations
« Reply #44 on: March 22, 2010, 09:20:19 pm »

Quote from: Ray
If you don't need a feature, don't select it or activate it.

Every feature even when deactivated has a cost: poorer ergonomic design, compromised de-activated function (I'm thinking particularly of the dismal viewfinders of AF cameras) and each feature is is an opportunity for Murphy's Law to rear it's famous head.

Quote from: Ray
Doug,
Canon have already addressed this difficulty you refer to. My 50D has a 920,000 pixel LiveView screen. My 40D also has a Liveview screen, but only 230,000 pixels.

Have you ever tried focussing using live view with an active subject?

Quote from: Ray
The fact is, autofocussing is never perfectly accurate (except perhaps by accident), no matter how expensive the lens.

Which is exactly why I favor a good optical viewfinder over AF or live view.

Quote from: Ray
As a person who is a bit obsessed with issues of resolution, I would not be interested in buying a lens which could not autofocus properly, according to my own standards. But many 'more normal' people might be quite satisfied with a lens that I would reject.

If you're obsessed with resolution you might be better off eschewing AF altogether.

Quote from: Ray
I would hope that autofussing bracketing will become a feature in future DSLRs.

It would be absolutely useless to me.  For the 1/10 of a second a bird's posture is what I want, I want accurate focus.  Not accurate focus on the exposure before or the exposure after.  Accuracy beats spray & pray.
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Ray

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Interesting article on sample variations
« Reply #45 on: March 22, 2010, 11:54:56 pm »

Quote from: telyt
Every feature even when deactivated has a cost: poorer ergonomic design, compromised de-activated function (I'm thinking particularly of the dismal viewfinders of AF cameras) and each feature is is an opportunity for Murphy's Law to rear it's famous head.

This is a fallacy. The way it works according to economic reality is: the more features, the more attractive the item becomes to the public at large, and the more units are sold. As a consequence, the cost becomes lower or the quality becomes higher at the same cost. Just because you personally may have no use for a particular feature, does not mean that no-one else does. For example, I never shoot in jpeg mode with a DSLR. However, I don't find the option to shoot jpeg a disadvantage in any way, nor do I think such an option could contribute towards camera mal-function.

However, this is not always the case. A particular feature which puts more stress on a mechanical component in the camera may contribute towards its mal-function. For example, after about 100,000 shots with my Canon 5D, the mirror fell off. I don't believe this was due to the actual quantity of shutter actuations but due to my frequent use the 'autobracketing-of-exposure' feature which causes the mirror to flip up and down rapidly 3 times at each press of the shutter button.

If you had no use for such a feature, preferring an accurate exposure reading from a hand-held Weston, as Rob does, then your mirror is not likely to fall off as a result of not using the autobracket feature.

Quote
Have you ever tried focussing using live view with an active subject?

Any type of accurate manual focussing with an active subject is difficult. Autofocussing is a relatively modern feature in cameras. I renewed my interest in Photography about 25 years ago with the purchase of the first autofocus SLR, the Minolta Maxxum 7000. I later switched to Canon because of another great feature, Image Stabilisation.

Quote
Which is exactly why I favor a good optical viewfinder over AF or live view.

Please enlighten me. I've never heard of any optical viewfinder that is a patch on the Canon LiveView system, provided you are able to use a tripod. (A monopod might be too much of a compromise).

The image on my 50D LiveView screen can be magnified 10x for the most accurate of manual focussing. That means, in effect, when you are using a 400mm lens that fills the screen with, say, the body of a bird, you can magnify the scene 10x which is equivalent to looking at the bird with a 4,000mm lens. It's eyeball fills the screen. Whether or not the bird will sit still long enough for you to accurately focus on its 3rd eyelash to the right of its left eye, is another matter. (Okay! Birds may not have eyelashes. Could we say they have eye bristles?   ).

Quote
If you're obsessed with resolution you might be better off eschewing AF altogether.

If I were very obsessed I probably would, but I'm only a bit obsessed.  

Quote
It would be absolutely useless to me. For the 1/10 of a second a bird's posture is what I want, I want accurate focus. Not accurate focus on the exposure before or the exposure after. Accuracy beats spray & pray.

Now! now! Doug, I can't believe that. First, there's no exposure before, only exposures after. The shot which is a fraction of a second immediately after the one envisaged (or the second or third or 4th or 5th one after) might not only be the perfectly focussed shot, but the preferred posture and composition. Some of the greatest shots in the history of photography have been fortuitous accidents

Nevertheless, irrespective of whether or not one's camera has the feature of autofocus bracketing, one would like the camera to have as accurate a focus as possible on that first shot. As far as I know, absolute auto-focussing accuracy does not exist, but manual focussing of a 10x enlarged image on a high resolution LiveView screen is the next best thing.


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ErikKaffehr

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Interesting article on sample variations
« Reply #46 on: March 23, 2010, 02:02:45 am »

Hi,

Just a few comments.

I wouldn't agree that current viewfinders are bad in general. APS-C cameras are often pentamirror designs but top class cameras use pentaprisms. Another issue is that modern focusing screen assemblies are not really intended for focusing but more to be bright. The focusing screens are often user changable.

The focusing system includes the mirror and the focusing screen, in AF systems we have an additional mirror casting an image on the AF-sensor, both mirrors are moving.

To get correct focus all parts, moving or not, must be aligned within say 10 microns, not a small feat. There is also thermal expansion which may effect the focusing mechanism. Replacing a finder screen may reduce accuracy.

The eyefinder magnification is not really good enough for critical focusing. Microprisms/Split image may help. Exact focusing is probably best achieved by finding near and far limits of focus and positioning the focusing ring midway between.

Live view removes all uncertainty. Focusing is done on actual pixels coming from the sensor, so axial alignment errors are compensated for. Would the sensor not be perpendicular to the optical axis of the lens critical focus could still be achieved at the point used for focusing.

Live view does not add complexity to the system, but at the present state of art it's quite slow, because the shutter needs to be closed and re-cocked before exposure.

I recommend this reading:

http://theonlinephotographer.typepad.com/t...ng-follies.html

http://www.josephholmes.com/news-medformatprecision.html

Best regards
Erik


Quote from: telyt
Every feature even when deactivated has a cost: poorer ergonomic design, compromised de-activated function (I'm thinking particularly of the dismal viewfinders of AF cameras) and each feature is is an opportunity for Murphy's Law to rear it's famous head.



Have you ever tried focussing using live view with an active subject?



Which is exactly why I favor a good optical viewfinder over AF or live view.



If you're obsessed with resolution you might be better off eschewing AF altogether.



It would be absolutely useless to me.  For the 1/10 of a second a bird's posture is what I want, I want accurate focus.  Not accurate focus on the exposure before or the exposure after.  Accuracy beats spray & pray.
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Erik Kaffehr
 

telyt

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Interesting article on sample variations
« Reply #47 on: March 23, 2010, 06:19:40 am »

Quote from: ErikKaffehr
I wouldn't agree that current viewfinders are bad in general.
Have you compared them with a good manual-focus SLR viewfinder?  A Nikon F with E viewscreen or a Leicaflex SL viewfinder exposes the top-of-the-line AF camera's viewfinder as the compromised tools they are.  I don't know what's more unfortunate, that one of the photographers most important tools, the viewfinder, has been compromised in order to include a convenience feature of dubious accuracy, or that people accept this as state-of-the-art.

[!--quoteo(post=0:date=:name=ErikKaffehr)--][div class=\'quotetop\']QUOTE (ErikKaffehr)[div class=\'quotemain\'][!--quotec--]Live view removes all uncertainty.[/quote]
I agree, but try using live view on an active subject.  These photos were made using a manual-focus optical viewfinder:





« Last Edit: March 23, 2010, 06:20:07 am by telyt »
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Ray

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Interesting article on sample variations
« Reply #48 on: March 23, 2010, 07:16:34 am »

Quote from: telyt
Have you compared them with a good manual-focus SLR viewfinder?  A Nikon F with E viewscreen or a Leicaflex SL viewfinder exposes the top-of-the-line AF camera's viewfinder as the compromised tools they are.  I don't know what's more unfortunate, that one of the photographers most important tools, the viewfinder, has been compromised in order to include a convenience feature of dubious accuracy, or that people accept this as state-of-the-art.


I agree, but try using live view on an active subject.  These photos were made using a manual-focus optical viewfinder:

 
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Rob C

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Interesting article on sample variations
« Reply #49 on: March 23, 2010, 05:44:10 pm »

Quote from: telyt
Have you compared them with a good manual-focus SLR viewfinder?  A Nikon F with E viewscreen or a Leicaflex SL viewfinder exposes the top-of-the-line AF camera's viewfinder as the compromised tools they are.  I don't know what's more unfortunate, that one of the photographers most important tools, the viewfinder, has been compromised in order to include a convenience feature of dubious accuracy, or that people accept this as state-of-the-art.





That's something I can sympathise and agree with, but I would still go with the standard split-image one that came with the body unless the horizon line of the sea was included in the shot; I always found that getting it right, hand-held, in vertical shots especially, was always a dodgy hope at best! That was why I bought the checkered screen for those occassions, though even then, it was better doing it on a tripod.

Your last bit, about people now accepting the compromised solutions they get as okay, really burns me up, as I have stated several times over with the growing sense of crying to myself in the wilderness. For those who remember nothing better, great; for those who know better, it is a gross betrayal by the marques we trusted and supported over a lifetime.

I wish there were more with your thoughts.

Rob C

Ray

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Interesting article on sample variations
« Reply #50 on: March 23, 2010, 07:10:33 pm »

Quote from: Rob C
That's something I can sympathise and agree with, but I would still go with the standard split-image one that came with the body unless the horizon line of the sea was included in the shot; I always found that getting it right, hand-held, in vertical shots especially, was always a dodgy hope at best! That was why I bought the checkered screen for those occassions, though even then, it was better doing it on a tripod.

Your last bit, about people now accepting the compromised solutions they get as okay, really burns me up, as I have stated several times over with the growing sense of crying to myself in the wilderness.

Rob,
Whilst I agree that the old 'split image' method for manual focussing is vastly easier and more accurate than trying to assess sharpness through a plain viewfinder, I don't agree that everyone accepts compromised solutions as okay. Everytime Canon produces a new model with an autofocus tracking problem, there's a great hullabaloo. (Was it the 1D3 that had  such a problem investigated by Rob Galbraith?)

One of the great things about the Canon LiveView system is that the mirror remains up when you take the shot, so you not only get the benefit of perfectly accurate manual focussing, (even more accurate than the 'split image' method when conditions are stable), but the benefit of MLU for that ultimate, vibration-free, tack-sharp image.

If you really want the old-fashioned split-image focussing screen, I believe there are third party suppliers catering to your needs. Here's one for the Canon 5D and 5D2.    http://haodascreen.com/Canon5D.aspx
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telyt

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Interesting article on sample variations
« Reply #51 on: March 23, 2010, 09:58:17 pm »

Quote from: Ray
Excellent and well-focussed shots, Doug. Are all your shots like that, or do you get a few out-of-focus sometimes?  

These are from single exposures, not the pick of a sequence.  I did not 'spray & pray'.
« Last Edit: March 23, 2010, 09:59:14 pm by telyt »
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