Newbie question - older lenses with digital SLR?

Archived from groups: rec.photo.digital (More info?)

Scott Gardner wrote:
> On Fri, 26 Aug 2005 23:02:34 +1000, "Mike Warren"
> <miwa-not-this-bit@or-this-cairnscarsound.com.au> wrote:
>
> >Scott Gardner wrote:
> >> I currently have a Nikon N55 (film), and I'm about to upgrade to a
> >> Nikon D50 digital. I already have several lenses for the N55 that I
> >> know will work with the D50, so I'm planning on just buying the D50
> >> body and re-using my current lenses.
> >>
> >> I'm confused about the "magnification factor" of the D50, though. I
> >> know that the D50 has a 1.5X magnification factor, so my old 200mm
> >> lens will behave like a 300mm lens, and my 14mm will act like a 21mm.
> >> What I'm unsure of is how I'll need to frame my shots. With the old
> >> lenses on the new camera, will a portion of what I see through the
> >> viewfinder be lost, or will the image I see through the viewfinder
> >> still accurately depict what will be recorded?
> >
> >The vewfinder will show you what you will get in the final picture.
> >About 95% of it anyway.
> >
> >-Mike
> >
> Thanks - so if I were to stand in one spot and frame a scene with the
> old camera and 200mm lens, and then swap the lens over to the new
> camera, the magnification will be evident in the viewfinder, and not
> just in the final photograph?
>
> That's what I was hoping - that I could continue to use my old lenses
> without having to mentally crop out a significant portion of the view
> through the viewfinder.

After shooting for a couple of months with a D70s and a 24-120mm VR
lens, I "dusted off" the N80 and attached the lens to it. Stunning how
much wider an angle of view you get with 35mm.

Ben

Archived from groups: rec.photo.digital (More info?)

Scott Gardner <gardners14@cox.net> wrote:
>I currently have a Nikon N55 (film), and I'm about to upgrade to a
>Nikon D50 digital. I already have several lenses for the N55 that I
>know will work with the D50, so I'm planning on just buying the D50
>body and re-using my current lenses.
>
>I'm confused about the "magnification factor" of the D50, though. I
>know that the D50 has a 1.5X magnification factor, so my old 200mm
>lens will behave like a 300mm lens, and my 14mm will act like a 21mm.
>What I'm unsure of is how I'll need to frame my shots. With the old
>lenses on the new camera, will a portion of what I see through the
>viewfinder be lost, or will the image I see through the viewfinder
>still accurately depict what will be recorded?

It is *exactly* the same as the effect one gets using different
sized films too. Any given focal length provides different
"magnification" with a different size film.

Lenses designed for 2-1/4" film work just fine with 35mm too,
but the "normal" lens for each is different. The same is true
going from 35mm to a smaller digital image sensor.

But since few 2-1/4" cameras have the same mount that 35mm
cameras do, those lenses are rarely used for 35mm work. On the
other hand, the same mounts are used by 35mm and digital
cameras, so 35mm lenses will work.

And there is an added benefit too, because most lenses are best
corrected in the center of the image, and whatever aberations,
etc. exists will be at the outer edges... which is the part not
used by digital cameras! Hence some of the cheaper lenses that
are not suitable for serious 35mm work might well be quite sharp
in the center area used by digital cameras.

--
FloydL. Davidson http://web.newsguy.com/floyd_davidson
Ukpeagvik (Barrow, Alaska) floyd@barrow.com

Archived from groups: rec.photo.digital (More info?)

Scott Gardner wrote:
> I currently have a Nikon N55 (film), and I'm about to upgrade to a
> Nikon D50 digital. I already have several lenses for the N55 that I
> know will work with the D50, so I'm planning on just buying the D50
> body and re-using my current lenses.
>
> I'm confused about the "magnification factor" of the D50, though. I
> know that the D50 has a 1.5X magnification factor, so my old 200mm
> lens will behave like a 300mm lens, and my 14mm will act like a 21mm.
> What I'm unsure of is how I'll need to frame my shots. With the old
> lenses on the new camera, will a portion of what I see through the
> viewfinder be lost, or will the image I see through the viewfinder
> still accurately depict what will be recorded?

The vewfinder will show you what you will get in the final picture.
About 95% of it anyway.

-Mike

Archived from groups: rec.photo.digital (More info?)

On Fri, 26 Aug 2005 23:02:34 +1000, "Mike Warren"
<miwa-not-this-bit@or-this-cairnscarsound.com.au> wrote:

>Scott Gardner wrote:
>> I currently have a Nikon N55 (film), and I'm about to upgrade to a
>> Nikon D50 digital. I already have several lenses for the N55 that I
>> know will work with the D50, so I'm planning on just buying the D50
>> body and re-using my current lenses.
>>
>> I'm confused about the "magnification factor" of the D50, though. I
>> know that the D50 has a 1.5X magnification factor, so my old 200mm
>> lens will behave like a 300mm lens, and my 14mm will act like a 21mm.
>> What I'm unsure of is how I'll need to frame my shots. With the old
>> lenses on the new camera, will a portion of what I see through the
>> viewfinder be lost, or will the image I see through the viewfinder
>> still accurately depict what will be recorded?
>
>The vewfinder will show you what you will get in the final picture.
>About 95% of it anyway.
>
>-Mike
>
Thanks - so if I were to stand in one spot and frame a scene with the
old camera and 200mm lens, and then swap the lens over to the new
camera, the magnification will be evident in the viewfinder, and not
just in the final photograph?

That's what I was hoping - that I could continue to use my old lenses
without having to mentally crop out a significant portion of the view
through the viewfinder.




--
Scott Gardner

"Oh look, things are going from bad to worse!"

Archived from groups: rec.photo.digital (More info?)

"Scott Gardner" <gardners14@cox.net> wrote in message
news b8ug1lhfom3vvb6rccqetqjlhmmk96lsj@4ax.com...
> On Fri, 26 Aug 2005 23:02:34 +1000, "Mike Warren"
> <miwa-not-this-bit@or-this-cairnscarsound.com.au> wrote:
>
>>Scott Gardner wrote:
>>> I currently have a Nikon N55 (film), and I'm about to upgrade to a
>>> Nikon D50 digital. I already have several lenses for the N55 that I
>>> know will work with the D50, so I'm planning on just buying the D50
>>> body and re-using my current lenses.
>>>
>>> I'm confused about the "magnification factor" of the D50, though. I
>>> know that the D50 has a 1.5X magnification factor, so my old 200mm
>>> lens will behave like a 300mm lens, and my 14mm will act like a 21mm.
>>> What I'm unsure of is how I'll need to frame my shots. With the old
>>> lenses on the new camera, will a portion of what I see through the
>>> viewfinder be lost, or will the image I see through the viewfinder
>>> still accurately depict what will be recorded?
>>
>>The vewfinder will show you what you will get in the final picture.
>>About 95% of it anyway.
>>
>>-Mike
>>
> Thanks - so if I were to stand in one spot and frame a scene with the
> old camera and 200mm lens, and then swap the lens over to the new
> camera, the magnification will be evident in the viewfinder, and not
> just in the final photograph?
>
> That's what I was hoping - that I could continue to use my old lenses
> without having to mentally crop out a significant portion of the view
> through the viewfinder.
>
Don't think magnification; think crop. A dSLR crops the image formed by the
lens to the size of the sensor. As the size of the sensor on a D50 is
smaller than the size of a 35mm frame, the lens image is cropped to fit.
Hence, the angle of view on a dSLR is smaller. The image size on the sensor
using any lens corresponds to the image size on a 35mm frame of a lens with
1.5 the focal length.
Jim

Archived from groups: rec.photo.digital (More info?)

On Fri, 26 Aug 2005 14:17:26 GMT, "Jim" <j.n@nospam.com> wrote:


>Don't think magnification; think crop. A dSLR crops the image formed by the
>lens to the size of the sensor. As the size of the sensor on a D50 is
>smaller than the size of a 35mm frame, the lens image is cropped to fit.
>Hence, the angle of view on a dSLR is smaller. The image size on the sensor
>using any lens corresponds to the image size on a 35mm frame of a lens with
>1.5 the focal length.
>Jim
>

Thanks again. I knew the reason behind the crop/magnification
(smaller sensor on the digital camera compared to a frame of film),
but I wasn't sure how the viewfinder figured into the equation. I was
afraid that with a non-digital-specific lens, the view through the
viewfinder might show me a different angle of view than the camera's
sensor would "see".

Thinking about it further, I guess the whole point of an SLR is that
the viewfinder accurately reflects what's going to hit the film (or
sensor), so I probably should have known it wasn't going to be an
issue, but it was nice to get the confirmation from you.
--
Scott Gardner

"I've been accused of vulgarity. I say that's bullshit." (Mel Brooks)

Archived from groups: rec.photo.digital (More info?)

Scott Gardner wrote:
> Thanks - so if I were to stand in one spot and frame a scene with the
> old camera and 200mm lens, and then swap the lens over to the new
> camera, the magnification will be evident in the viewfinder, and not
> just in the final photograph?

Yes.

-Mike

Archived from groups: rec.photo.digital (More info?)

"Jim" <j.n@nospam.com> wrote in message
news:WvFPe.2792$eQ.678@newssvr30.news.prodigy.com...
>
> "Scott Gardner" <gardners14@cox.net> wrote in message
> news b8ug1lhfom3vvb6rccqetqjlhmmk96lsj@4ax.com...
>> On Fri, 26 Aug 2005 23:02:34 +1000, "Mike Warren"
>> <miwa-not-this-bit@or-this-cairnscarsound.com.au> wrote:
>>
>>>Scott Gardner wrote:
>>>> I currently have a Nikon N55 (film), and I'm about to upgrade to a
>>>> Nikon D50 digital. I already have several lenses for the N55 that I
>>>> know will work with the D50, so I'm planning on just buying the D50
>>>> body and re-using my current lenses.
>>>>
>>>> I'm confused about the "magnification factor" of the D50, though. I
>>>> know that the D50 has a 1.5X magnification factor, so my old 200mm
>>>> lens will behave like a 300mm lens, and my 14mm will act like a 21mm.
>>>> What I'm unsure of is how I'll need to frame my shots. With the old
>>>> lenses on the new camera, will a portion of what I see through the
>>>> viewfinder be lost, or will the image I see through the viewfinder
>>>> still accurately depict what will be recorded?
>>>
>>>The vewfinder will show you what you will get in the final picture.
>>>About 95% of it anyway.
>>>
>>>-Mike
>>>
>> Thanks - so if I were to stand in one spot and frame a scene with the
>> old camera and 200mm lens, and then swap the lens over to the new
>> camera, the magnification will be evident in the viewfinder, and not
>> just in the final photograph?
>>
>> That's what I was hoping - that I could continue to use my old lenses
>> without having to mentally crop out a significant portion of the view
>> through the viewfinder.
>>
> Don't think magnification; think crop.

No. Don't think crop, think magnification. That's what it is. Nothing is
being cropped.


> A dSLR crops the image formed by the lens to the size of the sensor. As
> the size of the sensor on a D50 is smaller than the size of a 35mm frame,
> the lens image is cropped to fit. Hence, the angle of view on a dSLR is
> smaller. The image size on the sensor using any lens corresponds to the
> image size on a 35mm frame of a lens with 1.5 the focal length.

In other words, it's magnified 1.5 times, which is what he said in the first
place. The 200mm lens becomes *effectively* a 300mm lens because of the 1.5x
magnification factor.

We are all accustomed to think of focal length in 35mm terms. Everyone
understands this. Camera makers, periodicals, reviewers all provide 35mm
equivalents for focal lengths, and rightly so, since the actual focal
lengths are relatively meaningless--and will be as long as there are so many
different sensor sizes used.

Nothing is being cropped by the camera--unless some feature such as aspect
ratio modification is employed, which is not the usual thing, and then the
crop is very minor anyway. It makes no more sense to say the smaller sensor
is "cropping" anything than it would to say a 4x5 view camera is "cropping"
when it uses a lens which would also work on an 8x10 camera. In fact, many
lenses today designed specifically for digital SLRs only have a useful image
circle sized for those cameras. Does it make any sense at all to say a
camera is "cropping" something when it's using the full image size the lens
is capable of? (Rhetorical question.)

N.

Archived from groups: rec.photo.digital (More info?)

"Scott Gardner" <gardners14@cox.net> wrote in message
news:0ueug1tb5b1ratg22nt733d7fir5mvei07@4ax.com...
> On Fri, 26 Aug 2005 14:17:26 GMT, "Jim" <j.n@nospam.com> wrote:
>
>
>>Don't think magnification; think crop. A dSLR crops the image formed by
>>the
>>lens to the size of the sensor. As the size of the sensor on a D50 is
>>smaller than the size of a 35mm frame, the lens image is cropped to fit.
>>Hence, the angle of view on a dSLR is smaller. The image size on the
>>sensor
>>using any lens corresponds to the image size on a 35mm frame of a lens
>>with
>>1.5 the focal length.
>>Jim
>>
>
> Thanks again. I knew the reason behind the crop/magnification
> (smaller sensor on the digital camera compared to a frame of film),

You were correct about magnification in the first place. There is no
cropping being done. It sure would be nice if people ceased and desisted
from this silly misuse of "crop."


> but I wasn't sure how the viewfinder figured into the equation. I was
> afraid that with a non-digital-specific lens, the view through the
> viewfinder might show me a different angle of view than the camera's
> sensor would "see".
>
> Thinking about it further, I guess the whole point of an SLR is that
> the viewfinder accurately reflects what's going to hit the film (or
> sensor), so I probably should have known it wasn't going to be an
> issue, but it was nice to get the confirmation from you.

It was a fair question anyway, but right. The viewfinder system is designed
for the size of the film or sensor and will show only the amount of image
that the film or sensor will receive.

N.

Archived from groups: rec.photo.digital (More info?)

I did the same and went from a Nikon F80 to a Nikon D70.
Some lenses work out well; the old standard 50mm f1.4 is now a very nice
portrait lens at 75mm f1.4
but your old wide angle 24mm lens goes up to 36mm.
Its just swings and roundabouts.