Re: more about the camera design I would like to have

On Tue, 14 Oct 2008 23:35:12 +1100 dj_nme <dj_nme@xxxxxxxxxxxx> wrote:
| phil-news-nospam@xxxxxxxx wrote:

|> Now there are 2 ways to do this. One is to have a different (but similar
|> so adaptors work easily) mount that is actually closer. The other is to
|> keep the same mount as the SLR series, but have the rear element extend
|> out from the rear of the lens further. The disadvantage of the former is
|> it means a new mount system and the need for an adaptor for telephoto lenses.
|> The disadvantage of the latter is that the protruding rear element can be
|> more easily damaged when mounting the lens (and a mistake of trying to mount
|> it on an SLR can damage both lens and camera mirror).
|
| The final sentence above is the best argument for a different, shorter
| register lensmount.

I'd agree a shorter one would be safer for this aspect. But that does need to
be balanced against having this change that forces the use of an adaptor to be
able to use all those SLR lenses. It would be a tough decision, although the
people in the marketing department of a manufacturer might not think it is so
tough.


|> 1. uses an LCD display in the viewfinder in live mode, rather than a mirror.
|> 2. can work with very wide angle lenses made with a shallow/short design.
|> 3. uses a leaf shutter in newer lenses designed for it.
|> 4. has a full-frame sensor
|
| Olympus, Canon and Nikon have DSLR cameras which do No.1 (live-view) and
| display it on the rear LCD panel.

Indeed. And I have that on my 450D (the one the marketing people refer
to as a Rebel XSi).


| I believe that No.s 2&4 are the least likely to be put together in a
| real-world camera.

My hope is that these cameras (the "SLD" design) will have ONE high end model
with the full-frame sensor, with the lower 2 or 3 models using APS-C, much
like SLR does already. IOW, a parallel model line.


| Simply because the angle of incidence of light rays exiting the rear
| lens element is greater the further from the centre of the sensor and
| may not be fixable with microlenses on the pixel wells.

I have argued that this is fixable in software, as long as that software
has access to information about the lens (what the angle of incidence will
be) and the sensor (how much light loss will take place at these angles).
This could be done with a calibration shot against a uniformly lit surface.

OTOH, just to argue against my own preference, geometric distortion can be
corrected for in post processing workflow by software. So a lens without
a rear element close to the sensor, that accepts geometric distortion in
trade for lower costs and other factors, could still be usable.


|> | It has the shortest mount-to-sensor distance with a large sensor (both
|> | APS-c and 35mm FF) and can be adapted with mechanical rings to use most
|> | other lenses (except 4/3 and Leica RF).
|>
|> It has been said that there exists an adaptor that can mount Nikon lenses
|> (without any AF function, and without any reading of f/stop) onto an EOS
|> camera. So far I have been unable to find it.
|
| Ebay has pages of them for sale at any time.

I'd rather buy one from a reputable retailer, such as B&H.


| Type "nikon eos adapter" into the eBay search field and then press
| "enter", you will find many of them.

I've been ripped off in EBAY and by PAYPAL. So I don't do those anymore.


|> But I want to have a camera without the mirror and better wide angle lenses.
|
| The only option for that now is with a Leica M8 (or M8.2), you can mount
| lenses which are so intrusive into the body that they almost touch the
| shutter.

Now what we need to do is get them to do a leaf shutter.


|> You mean have the viewfinder out further to "fit a face"?
|
| Yes, something like this (disregarding the hump/housing for the pop-up
| flash):
| <http://a.img-dpreview.com/news/0407/Panasonic/hands-on/fz20inhand01-001.jpg>

That viewfinder is a bit too far to the left for me. I suppose maybe it
could be used to the left eye. I just don't see any real reason to move the
viewfinder around much. But I guess there is adequate reason to do some
ergonomic research for this ... as long as it is done with high end hobbyists
and professionals, including uses on tripod (something you really do need to
look in the viewfinder when the light is too bright) and with big heavy
lenses that are still within handhold size.

And the whole thing is too small. Or else someone has a HUGE hand :-)


|> |> | The problem with that is that if the LCD is articulated from the left
|> |> | hand edge, then it would have to be smaller so as to not interfere with
|> |> | the EVF, but it could be articulate on the top or bottom edge instead.
|> |> | The same design features could just as easily be incorporated into a
|> |> | body with a larger (APS-c or 35mm FF) sensor, but then it will always be
|> |> | at least slightly bulkier than could be achieved with a 4/3 sized sensor.
|> |>
|> |> I think I really don't know what you are referring to with this "articulated"
|> |> reference. Is this a "pop out" viewfinder like cheap camcorders have?
|> |
|> | You've never seen a digicam with an LCD which can fold out and twist around?
|> | That's what's called "articulated LCD": it isn't fixed in position to
|> | the back of the camera.
|>
|> Yes I have. I don't see much value in that. Video cameras tend to be in a
|> body design that is narrow left-to-right (a legacy from the days of vidicon
|> tubes). A monitor display on the back would be forced to be small. Having
|> one that pops out from the side is a plus for that body style. The twist
|> might be good for seeing yourself when making a video blog on the run, or
|> when you play back a video.
|>
|> That's less important (at least to me ... there probably are people that
|> would love it) for a photo camera in the legacy cartridge film body style.
|
| Then I suppose that you don't anticipate shooting at odd angles, such as
| over head or close to the ground?

OK, it can help there.


| Having an LCD screen which can be twisted around for easy viewing so
| that you don't have to climb onto something or lie on the ground in
| order to look through the viewfinder eyepiece is not a good idea?

OK, it can help for that.


|> OK, I'll use that term. But one inside for the "up to the face" viewfinder,
|> and another on the back for "on the tripod" use. Maybe someone can find a
|> clever way to use one LCD alone for both needs in a way that is cheaper than
|> using 2 of them. But for electrical power purposes, only 1 of them needs to
|> be turned on at a time.
|
| Konica-Minolta made two EVF digicams (the Z1 and Z2) that had one LCD
| for both eye-level finder and rear of body, but the real problem with
| this design is that the internally pivoting screen takes up quite a bit
| of space inside the camera body.
| I really don't believe that it would be suitable for a camera with a
| large sensor, as a big chunk of volume has be reserved for the LCD to
| pivot internally and that would make the proposed camera body rather
| large and bulky.

Why an INTERNAL pivot? I can accept the external one being be twistable.
What does the internal one need to do?

--
|WARNING: Due to extreme spam, googlegroups.com is blocked. Due to ignorance |
| by the abuse department, bellsouth.net is blocked. If you post to |
| Usenet from these places, find another Usenet provider ASAP. |
| Phil Howard KA9WGN (email for humans: first name in lower case at ipal.net) |
.

Relevant Pages

  • Re: Nikon D40 with 300mm lens AND teleconverter (Nikkor AF-S Teleconverter TC-20E II)
    ... capable EOS system and it's EF mount. ... and 40 year old lenses still mount and work perfectly ... Matrix/evaluative metering may be degraded, as the camera cannot ...
    (rec.photo.digital.slr-systems)
  • Re: Would You Do this to a Lens?
    ... lenses have been made in all number of different camera ... The trick is to mount these lenses to a modern camera is ... Otherwise, T-mount adapters of various kinds, ...
    (alt.photography)
  • Re: Would You Do this to a Lens?
    ... lenses have been made in all number of different camera ... The trick is to mount these lenses to a modern camera is ... step-up and step-down and reverse adapters are all ...
    (alt.photography)
  • Re: lens hacking question: good movie camera lenses?
    ... C-mount, exacta mount. ... what systems let converted lenses work. ... of the camera body is another way to look at this. ... any DSLR lens mount by already available adapters. ...
    (rec.photo.digital.slr-systems)
  • Re: Horrors spawned by P&S marketing
    ... P&S cameras can have more seamless zoom range than any DSLR glass in ... slightly greater detail retention when upsampled directly in the camera for JPG ... used in many of them today, the lenses for these cameras are much smaller. ... P&S cameras have 100% viewfinder coverage that exactly matches your final ...
    (rec.photo.digital)