Difference between lenses for film and lenses for digital?

One4All wrote:
> Is there a difference between lenses made for photographing with film
> vs. digital photographing? I've read that there is. I ask because I
> want to buy one of the new Pentax K cameras that will allow me to use
> my film lenses. If there is a difference, is it so small as to make the
> issue irrelevant?
>

According to Canon there is a difference, how much of a difference or
does the difference matter in the real world is debatable. Canon makes
lenses they label as DO. These lenses direct light entering the sensor
differently than conventional lenses. Conventional lenses direct light
in an angular manner with is suitable for film but not as well suited
for a sensor.

Does it really matter? Will photographic differences be obvious? Not
that I can see in a finished print. At this time, in availability of
lenses and lens design, I think it's irrelevant.
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

Is there an adapter that will allow the use of lenses from other brands on
a Canon 20D? Is there any place to buy quality used lenses?
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

In article <pan.2007.01.07.02.45.27.273998.RemoveThis@digitalcity.net>, Chuck
Dubois <C_Dubois.RemoveThis@digitalcity.net> wrote:

> Is there an adapter that will allow the use of lenses from other brands on
> a Canon 20D?

Yes.

> Is there any place to buy quality used lenses?

Yes.

--
You need only reflect that one of the best ways to get yourself a
reputation as a dangerous citizen these days is to go about repeating
the very phrases which our founding fathers used in the struggle for
independence.
-- Charles A. Beard
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

One4All wrote:
> Is there a difference between lenses made for photographing with film
> vs. digital photographing? I've read that there is. I ask because I
> want to buy one of the new Pentax K cameras that will allow me to use
> my film lenses. If there is a difference, is it so small as to make the
> issue irrelevant?

Thanks to all for their very relevant information.
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

One4All <dwerner DeleteThis @bresnan.net> wrote:

> Is there a difference between lenses made for photographing with film
> vs. digital photographing? I've read that there is. I ask because I
> want to buy one of the new Pentax K cameras that will allow me to use
> my film lenses. If there is a difference, is it so small as to make the
> issue irrelevant?

In the case of Pentax lenses, you can use all K-mount lenses that have
an A setting on the aperture ring, or which don't have an aperture ring.
And even if they don't have an A setting on the aperture ring, you can
change a custom setting to allow you to use the aperture ring instead of
the thumb wheel to set aperture.

Pentax is making digital-only lenses now ('DA' in the nomenclature), but
the only real difference is that they produce a smaller image circle,
since the digital sensor is smaller than film. This means you'll likely
get vignetting if you use a digital-only lens on a film body. But other
than that, and with the caveats that have always been true of FA-J
lenses, there's no mechanical reason why you couldn't do it.
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

This is the question that I am still getting new inputs from time to
time. I only get to learn some more after I hit the problem. Here's
what I learned so far, but may need to be corrected.

1. nonuniform color-shift or vignet:

With some low end (midiumn format) digital sensors, some lenses
(partticularly in wide angle?) that work fine for films may show
visible non-uniform color shift or vignet.
One cause of this is the microlenses on the sensor. The
micro-lenses imposed extra directional sensitivity, that the sensor
elements at the cornor couldn't receive equal amount light compared to
the elements in the center. This problem had not happen on films, and
this problem would not shown on high end digital back. For example, I
heard that PhaseOne P25 or P45 are types that have no problem, but
P20/P21 may. Also, I heard all current 35mm FF digital cameras behaves
more like P20 that P25, and should be much worse.
This problem is usually much less in tele-lenses.

2. Light spectrum sensitivity:

The digital sensor has quite different wave-length sensitivity than
films. Some lenses designed for digital era are taking care of this
issues by different coating. I heard Carl Zeiss's new lenses (ZF) is an
example in dealing with this problems. I can expect newly release
lenses from Canon or Nikon may start to follow the similar practise. I
don't have true experiences on these new lenses, so you'll need to
search more to see if this is supported. -- but you need to take this
more serious when choosing the filters, For example, while warmer (1A?)
filter commonly apprears as the standard protection filter on film
camera, you might find the neutral-er filter is more common on digital
cameras.




Stephen M. Dunn wrote:
> In article <1168131304.931102.110220 RemoveThis @51g2000cwl.googlegroups.com> "One4All" <dwerner RemoveThis @bresnan.net> writes:
> $Is there a difference between lenses made for photographing with film
> $vs. digital photographing? I've read that there is. I ask because I
> $want to buy one of the new Pentax K cameras that will allow me to use
> $my film lenses. If there is a difference, is it so small as to make the
> $issue irrelevant?
>
> There are a couple of technical differences.
>
> One of the technical differences is that most DSLRs have sensors
> which are substantially smaller than the 35mm film frame. Lenses
> designed for use on 35mm bodies have to project an image circle
> which is large enough to cover the 35mm frame; lenses designed for
> digital cameras can get away with projecting a smaller image circle,
> and that can make the lens smaller and lighter than an equivalent
> lens for a 35mm camera would be. (It should also be cheaper, as it
> requires fewer raw materials, but the reduction in materials costs
> doesn't always make it through the production, marketing, and
> distribution process to the end user.)
>
> The other is that digital sensors tend to be more reflective than
> film. Lenses include anti-reflection features, but in the film days,
> these were primarily to cut down on problems caused by light reflecting
> off surfaces within the lens itself. On a digital body, light
> reflecting off the sensor is another issue, and so digital lenses
> typically take additional anti-reflection measures designed to
> reduce the impact of such reflections.
>
> That said, lots of us use "film" lenses on our DSLRs with great
> results, which goes to show that a substantial part of the reason
> for existence of "digital" lenses is marketing rather than technical.
> --
> Stephen M. Dunn <stephen RemoveThis @stevedunn.ca>
> >>>----------------> http://www.stevedunn.ca/ <----------------<<<
> ------------------------------------------------------------------
> Say hi to my cat -- http://www.stevedunn.ca/photos/toby/
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

> Is there a difference between lenses made for photographing with film
> vs. digital photographing? I've read that there is. I ask because I
> want to buy one of the new Pentax K cameras that will allow me to use
> my film lenses. If there is a difference, is it so small as to make the
> issue irrelevant?

According to the "Eyes of EOS" book, there is one possible difference.
Without going into technical detail, there are design characteristics of
particular individual elements within the lens which can make the lens
slightly more prone to flare *if* something is reflected back into the lens
from the film plane. Because digital sensors are more reflective than film,
Canon says that they have gone out of their way to produce lenses with more
appropriately-curved elements to reduce that phenomenon. There is also
consideration as to the coatings on individual elements, there is a pretty
wide range of combinations of which elements get coated in what ways, and
with what materials. (That can also infuence the color balance as well
resolution or flare.)

That being said, *good*, modern lenses (even those that weren't "designed
for digital") don't really seem to display more flare with digital than they
do with film, so there is evidence that if you're buying decent lenses to
begin with, there's nothing to worry about. Cheap lenses with particularly
bad design or particularly cheap coatings may show a bit more flare with
digital, but such lenses are going to be poor-performers even with film.

More than anything else, "designed for digital" seems to simply mean "This
lens has a smaller image circle, so it won't work on a film or full-frame
camera." (Perhaps unless you're buying bottom-of-the-barrel lenses anyway,
in which case, you're screwed anyway.)

steve
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

One4All wrote:
> Is there a difference between lenses made for photographing with film
> vs. digital photographing? I've read that there is. I ask because I
> want to buy one of the new Pentax K cameras that will allow me to use
> my film lenses. If there is a difference, is it so small as to make the
> issue irrelevant?

Properly designed lenses for sensors differ from film lenses. They are
telecentric, meaning the light rays enter the sensor surface as
perpendicular as possible. This has to be compared on a case by case
basis. However, people saying old 35mm film lenses will "vignette"
aren't very clear on the concept. Vignetting is caused by light fall
off at the edges of a lens's field. 35 mm lenses because they were
made to produce an image circle 35mm or more across do well in that
respect with smaller than FF digital sensors. Here is an example.
http://www.pbase.com/andersonrm/image/58937829.
Where they can fall down in performance (one area) concerns chromatic
aberration. Most older lenses don't use ED glass and other elements
needed to control this, so you end up with the blue fringing on
bright-dark interfaces. What was acceptable with film is not with most
digital sensors. But, ED glass costs money and cheap lenses are made
to be cheap. Which is also why you see colour error showing up on most
cheap P&S images.

The real problems occur when poor quality film lenses are used on FF
(Canon) sensors. The edge definition is terrible, showing all kinds of
aberrations from CA to SA to coma. In this case, eventually the camera
maker will have to create lenses designed to accommodate such a large
sensor.
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

"One4All" <dwerner DeleteThis @bresnan.net> wrote in message
news:1168131304.931102.110220@51g2000cwl.googlegroups.com...
> Is there a difference between lenses made for photographing with film
> vs. digital photographing? I've read that there is. I ask because I
> want to buy one of the new Pentax K cameras that will allow me to use
> my film lenses. If there is a difference, is it so small as to make the
> issue irrelevant?
>

Digital sensors reflect more light than film, so "digital" lenses may have
different coatings, element shapes etc. to minimise any ghost images caused
by the light reflected off the sensor surface. It's not a new phenomenon -
I can find decades old slides where bright point images against a dark
background have their duller ghosts imaged quite clearly. Good for the
marketing types to have something "new" and attractive for us.

--
M Stewart
Milton Keynes, UK



--
Posted via a free Usenet account from http://www.teranews.com
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

In article <1168131304.931102.110220 DeleteThis @51g2000cwl.googlegroups.com> "One4All" <dwerner DeleteThis @bresnan.net> writes:
$Is there a difference between lenses made for photographing with film
$vs. digital photographing? I've read that there is. I ask because I
$want to buy one of the new Pentax K cameras that will allow me to use
$my film lenses. If there is a difference, is it so small as to make the
$issue irrelevant?

There are a couple of technical differences.

One of the technical differences is that most DSLRs have sensors
which are substantially smaller than the 35mm film frame. Lenses
designed for use on 35mm bodies have to project an image circle
which is large enough to cover the 35mm frame; lenses designed for
digital cameras can get away with projecting a smaller image circle,
and that can make the lens smaller and lighter than an equivalent
lens for a 35mm camera would be. (It should also be cheaper, as it
requires fewer raw materials, but the reduction in materials costs
doesn't always make it through the production, marketing, and
distribution process to the end user.)

The other is that digital sensors tend to be more reflective than
film. Lenses include anti-reflection features, but in the film days,
these were primarily to cut down on problems caused by light reflecting
off surfaces within the lens itself. On a digital body, light
reflecting off the sensor is another issue, and so digital lenses
typically take additional anti-reflection measures designed to
reduce the impact of such reflections.

That said, lots of us use "film" lenses on our DSLRs with great
results, which goes to show that a substantial part of the reason
for existence of "digital" lenses is marketing rather than technical.
--
Stephen M. Dunn <stephen DeleteThis @stevedunn.ca>
>>>----------------> http://www.stevedunn.ca/ <----------------<<<
------------------------------------------------------------------
Say hi to my cat -- http://www.stevedunn.ca/photos/toby/
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

nick c wrote:
> According to Canon there is a difference, how much of a difference or
> does the difference matter in the real world is debatable. Canon makes
> lenses they label as DO. These lenses direct light entering the sensor
> differently than conventional lenses.

"DO" here is "Diffractive Optics", which allows long-focus lenses
to be physically smaller. It has essentially nothing to do with
digital vs. film.


--
--Bryan
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

On Jan 6, 8:20 pm, "David J. Littleboy" <davi... RemoveThis @gol.com> wrote:
> "One4All" <dwer... RemoveThis @bresnan.net> wrote:
> > Is there a difference between lenses made for photographing with film
> > vs. digital photographing? I've read that there is. I ask because I
> > want to buy one of the new Pentax K cameras that will allow me to use
> > my film lenses. If there is a difference, is it so small as to make the
> > issue irrelevant?For DSLRs, the basic rule is that _most_ digital lenses can't be used with
> film, and that _most_ film lenses can be used with digital.
>
> (Aside: Old Canon manual focus lenses are essentially unusable on any AF
> Canon body (film or digital), and Nikon is an amazingly confusing can of
> worms.)
>
> My understanding is that Pentax is one of the better companies in terms of
> supporting old film lenses. You should be able to use both your Pentax 67
> and Pentax 645 lenses just fine (as I understand it: I went Mamiya and not
> Pentax for my MF work, and my Mamiya 645 lenses are sort of usable on my
> 5D).
>
> But you need to "read the fine print". The Dpreview Pentax discussion forum
> should be able to answer specific questions.
>
> http://forums.dpreview.com/forums/forum.asp?forum=1036
>
> David J. Littleboy
> Tokyo, Japan

(Aside: Old Canon manual focus lenses are essentially unusable on any
AF
Canon body (film or digital), and Nikon is an amazingly confusing can
of
worms.)
OK the Canon FD lenses can't be used for digital, the Canon mounts are
completely different. Nikon is hardly a "can of worms" the only lenses
that can't be used on Nikon digital are the pre 1980 lenses that don't
have meter controls, all AI or AIS lenses can be used on digital Nikon
bodies. The new D40 does throw things off a bit, be cause it requires a
motor in the lens to autofocus. But still AI and AIS lenses can be
used.
There is really no reason not to use film lenses with digital, using
digital lenses on film may create some problems as they are designed to
cover the smaller APS sensor. 35mm framed digital cameras will have the
same problem with APS sized digital lenses, digital lenses maybe
problematical for 1.3x sensors from Canon and older Kodak DSLRs, so
film lenses maybe your only solution here too.
Unless the film lens is too old for the camera, Nikon, Canon, Pentax
(may need adapters that don't let the lens function fully) or
Minolta/Sony (older nonAF Minolta lenses). I don't think any of the
manufacturers have any restriction on any AF lenses (except the Nikon
D40).
My film designed Nikon 55 f 2.8 micro has to be one of the sharpest
lenses I have ever used, all the rest of my lenses are "film lenses"
and there is no problem on my D200. Two are pre autofocus, and work
well.

Tom
 >> Stay informed about: Difference between lenses for film and lenses for digital? 

One4All wrote:
> Is there a difference between lenses made for photographing with film
> vs. digital photographing? I've read that there is. I ask because I
> want to buy one of the new Pentax K cameras that will allow me to use
> my film lenses. If there is a difference, is it so small as to make the
> issue irrelevant?

Supposedly some of the lenses designed for digital have the rays in
image space (between rearmost surface of lens and image plane) more
nearly parallel to optical axis than film lenses because CCD chips are
a bit less sensitive to light striking the chip at extreme angles.
This is only really an issue with very short focal length large
aperture lenses (wide FOV and low f/#).

Since the falloff with either type of "sensor" is pretty severe anyway,
I don't worry about it much- also because I am not a fan of extreme
wide angle shots.
 >> Stay informed about: Difference between lenses for film and lenses for digital?