A fast scanner...

Barry Watzman wrote:

> Re: "ok but now don't think to a cheap device, think to a reflex digital
> camera at the top level with a full frame sensor and say 12 Mpixel
> being, as I read, the level of resolution of analog cameras. Stick some
> device to it just to hold firmly the slide at the correct distance, put
> some lens if necessary, i.e. design some "kit for digitalizing analog
> dias", why couldn't it work?"
>
> There are attachments for copying slides that screw into the adapter
> threads of lenses on more or less any camera. But the results just are
> never comparable to a good scanner, even when you use an extremely
> high-end camera.
>
> [By the way, what does "reflex" have to do with it? I don't think most
> of the people who talk about "reflex" cameras (as in SLR) have any idea
> what that actually means, or what they are talking about. "Reflex" does
> not, inherently, add anything to the quality of any digital camera. And
> it has no relevance whatsoever in this context. Granted that most DSLRs
> are very high end cameras, but a non reflex camera can be a better
> camera than a reflex camera; quality and "reflex" are not inherently
> related. There is nothing to prevent anyone from making a non-reflex
> digital camera with a full size 35mm image sensor (indeed, with exactly
> the same image sensor as ANY GIVEN DSLR). And with equal or better
> lenses, either fixed or interchangeable. In a film camera (where this
> all started) you HAD to have a reflex system because there was no way to
> compose the image without it. But with a digital camera, reflex is
> TOTALLY unnecessary AND it adds NOTHING to the quality; you can compose
> by looking at an LCD display from the image sensor (either screen or
> electronic viewfinder) and, by definition, you will see EXACTLY what the
> sensor will see when the image is taken. It is only because of the
> stupidity and ignorance of consumers and marketing's need to cater to
> that ignorance that all of the high end cameras have a totally
> unnecessary reflex system.]

It's not just the sensor, it's also things like being able to stop down the
lens to see the effect on depth of field (something sadly lacking on
non-reflex consumer cameras), being able to manually focus in situations
where autofocus fails (such as off-centre subject or photographing items in
glass cabinets where the camera can focus on the glass) and being able to
manually set shutter speed or aperature (better compacts can do this but
turning a dial like on an SLR is far easier and faster than stepping
through the options on a menu).

No reason all of these features can't be added to a non-SLR camera with LCD
viewfinder (the viewfinder is something I also miss on compact digitals)
but then you end up with a bridge camera that looks like an SLR, doesn't
cost that much less than a budget SLR, and still doesn't give you the
ability to change lenses. The larger full frame sensor is a larger part of
the cost of an SLR than the reflex mechanism, the main reason budget SLR's
often have smaller bridge camera sized sensor.

As an example Panasonic have added all these features to their latest model
but the price is a lot more than the cost of Nikon's cheapest SLR (I use a
fuji S5700 bridge camera but still miss these features and feel of my
all-manual Pentax P30 film SLR and currently looking for a pentax digital
to put my lenses back into use)

>
>
> Re: "Perhaps it could not do Digital ICE and noise removal but you can
> as well do it by Photoshop"
>
> I disagree with that; I do not think that any post-processing, no matter
> how good, can do as good a job as infra-red cleaning. IR cleaning has
> "access" to the original negative. Post Processing only has access to
> information about the original negative. There is a difference in those
> two things.

True - I've compared the Polaroid scratch removal software, it's better than
most software methods but still misses things that ICE corrects (like mould
damage) and can correct things that aren't faults (like removing the
windows on distant buildings).

Think about what you wrote.

We are discussing a DEDICATED device to take a picture of ("copy") a
35mm slide or negative.

THERE IS NO "DEPTH OF FIELD". NONE. You are "photographing" a piece of
35mm film. It's flat (well, more or less). Sure, the original image
may have had "depth of field", but we are not photographing the original
image, we are photographing a piece of film.

Similarly, devices that are scanning (or taking a picture of, or
copying) film (whether slides or negatives) normally do their auto-focus
on the GRAIN of the film, not on the image on the film (sometimes they
do have to drop back to the image if they can't focus on the grain).

This isn't a general purpose camera. Given the specific and dedicated
application, much of what you wrote doesn't make sense; it doesn't apply
to this particular, specific application.


Nigel Feltham wrote:
>
> It's not just the sensor, it's also things like being able to stop down the
> lens to see the effect on depth of field (something sadly lacking on
> non-reflex consumer cameras), being able to manually focus in situations
> where autofocus fails (such as off-centre subject or photographing items in
> glass cabinets where the camera can focus on the glass) and being able to
> manually set shutter speed or aperature (better compacts can do this but
> turning a dial like on an SLR is far easier and faster than stepping
> through the options on a menu).
>
> No reason all of these features can't be added to a non-SLR camera with LCD
> viewfinder (the viewfinder is something I also miss on compact digitals)
> but then you end up with a bridge camera that looks like an SLR, doesn't
> cost that much less than a budget SLR, and still doesn't give you the
> ability to change lenses. The larger full frame sensor is a larger part of
> the cost of an SLR than the reflex mechanism, the main reason budget SLR's
> often have smaller bridge camera sized sensor.
>
> As an example Panasonic have added all these features to their latest model
> but the price is a lot more than the cost of Nikon's cheapest SLR (I use a
> fuji S5700 bridge camera but still miss these features and feel of my
> all-manual Pentax P30 film SLR and currently looking for a pentax digital
> to put my lenses back into use)
>
>>
>> Re: "Perhaps it could not do Digital ICE and noise removal but you can
>> as well do it by Photoshop"
>>
>> I disagree with that; I do not think that any post-processing, no matter
>> how good, can do as good a job as infra-red cleaning. IR cleaning has
>> "access" to the original negative. Post Processing only has access to
>> information about the original negative. There is a difference in those
>> two things.
>
> True - I've compared the Polaroid scratch removal software, it's better than
> most software methods but still misses things that ICE corrects (like mould
> damage) and can correct things that aren't faults (like removing the
> windows on distant buildings).