From: Bruce on 14 May 2010 05:28
On Fri, 14 May 2010 08:05:15 +0800, "Wilba"
>> Some AF systems are even worse; Canon's being a
>> case in point, with fundamental errors built in to the system.
>Where can I find out more about this?
There have been many discussions on Usenet. Search in Google Groups
for contributions by David Kilpatrick, who gave the clearest possible
explanation of Canon's AF problems. You will find them either in
rec.photo.digital.slr-systems or rec.photo.equipment.35mm.
The problem is caused by Canon's choice of site for the AF sensors.
Nikon chose a different site and, as a result, their AF system has far
fewer problems than Canon's. But David Kilpatrick's explanation is
far clearer and more concise than anything I could manage.
From: Bruce on 14 May 2010 05:31
On Thu, 13 May 2010 14:53:19 -0700 (PDT), RichA <rander3127(a)gmail.com>
>On May 12, 6:30�pm, Bruce <docnews2...(a)gmail.com> wrote:
>> On Wed, 12 May 2010 13:48:13 -0700 (PDT), RichA <rander3...(a)gmail.com>
>> >WHO will be the company to release...a COMPACT FF camera??!
>> Leica already did it with the M9. �Wikipedia says:
>> "The Leica M9 is the second digital camera in the rangefinder M
>> series. It was introduced by Leica Camera AG on 9 September 2009. It
>> uses a 18.5-megapixel Kodak KAF-18500 Full Frame CCD image sensor."
>> Next question?
>It costs $10k with a 50mm lens. NEXT!!!
So you agree; Leica already did it with the M9.
What stupid question are you going to ask next?
From: Bruce on 14 May 2010 06:58
On Thu, 13 May 2010 19:23:43 -0500, BFD <bfd(a)zipnullnada.org> wrote:
>On Thu, 13 May 2010 23:09:16 +0100, Bruce <docnews2011(a)gmail.com> wrote:
>>On Thu, 13 May 2010 15:50:11 -0500, BFD <bfd(a)zipnullnada.org> wrote:
>>>I do understand the need for control of DOF. The identical DOF effects can
>>>be obtained from a smaller sensor by just changing the focal-length used.
>>Nonsense. Changing the angle of view would completely ruin the shot.
>>You really are a fool - you have not the faintest idea what you are
>Every shot of every subject is relative--to itself only. It is you who are
>the antiquated fool.
>You see a patch of flowers. To you, with your very limited DOF using a 50mm
>lens on a larger sensor camera, you will decide to get up close to that
>flower. You will get dozens of other blossoms and probably part of the sky
>in the background too with your wide FOV. How do you get rid of all those
>other distracting blotches of bright colors detracting from your subject
>and the blue of the sky which you don't even want?
Sorry, I don't shoot flowers. My job is shooting people. And using a
longer focal length means a narrower angle of view, which means
stepping back to a more remote viewpoint, which means an unflattering
rendition of the person's features.
This doesn't affect flowers in the same way. I agree that there is no
reason why you cannot use a longer focal length to shoot flowers on s
smaller format, as there are fewer conventional expectations of flower
shots than there are of portraits.
So, to come back to the original question, the reason why "full frame"
digital is so desirable is that it gives the same control over depth
of field that 35mm film does. Any sensor size smaller than "full
frame" (or 35mm film) gives too much depth of field. If there were
very wide aperture lenses available in the smaller formats it would
help, but the widest aperture lenses are those available for 35mm
film/full frame digital.
Of course portraiture was traditionally done with formats much larger
than 35mm. However, small apertures were needed to provide about the
same depth of field as a conventional portrait lens delivers somewhere
near wide open on 35mm film. The amount of depth of field is the
critical factor here, and small formats provide far too much depth of
field for good portraiture.
Which neatly answers the question, and takes us back to where we
From: Bruce on 14 May 2010 07:04
On Thu, 13 May 2010 19:27:04 -0500, Rich <none(a)nowhere.com> wrote:
>Depends if you want to preserve 3-dimensionality of the image. Using a
>450mm lens would basically flatten it.
Exactly. There is a reason why most lenses used for portraiture are
within a very short range of focal lengths. Anything significantly
longer or shorter gives a rendition that most people consider is
neither natural nor pleasant.
But "BFD" is mainly talking about flowers, where very different rules
apply. Flowers as subjects are much more tolerant of the different
apparent perspectives caused by using lenses of different focal
lengths. Although I don't do much macro photography, I do think that
greater depth of field, far from being a problem, would be something
that I would positively welcome. Just not for portraiture.
From: Bruce on 14 May 2010 07:07
On Thu, 13 May 2010 14:55:28 -0700 (PDT), RichA <rander3127(a)gmail.com>
>If Olympus had any sense, they'd do it and break the 4/3 straight
>jacket that confines them.
That would make no sense at all. Far better to stay in a format where
they have only one competitor who is also a partner.
Trying to break into the established APS-C and/or full frame market
would be commercial suicide. Sony tried it with the Alpha series of
DSLRs, and that has been a spectacular commercial failure, with very
slow sales and frightening losses.