Need advice on macro lenses
John Roberts
I could use some advice on a macro lens for a 35mm camera.
I've decided that I want the capability to take "studio" photos of small
objects, generally an inch or two across, with some range on either side.
I have experimented in the past with "close-up" lenses, but the lack of a
flat field would be a major problem with the types of photographs I want to
take. Naturally, I would like a good depth of field, but I realize that's
not always possible.
I've pretty much decided on a 100mm (non-zoom) macro for a non-autofocus
Canon or Minolta (FD or MD). (The cameras are A-1 and X-700.) I usually
keep the Minolta camera in a complex rig for another purpose, so I believe
the Canon lens would be much more convenient for me to use. However, the
price of the FD lens is going up rapidly, so if I want to get it, I suppose
I should get it soon. I believe both models come with extension tubes.
Can anyone offer advice on or comparison of these two lenses?
Thanks.
John Roberts
rob...@cmr.ncsl.nist.gov
Drew W. Saunders
rob...@CMR.NCSL.NIST.GOV (John Roberts) writes:
>
>I could use some advice on a macro lens for a 35mm camera.
>
>Canon or Minolta (FD or MD). (The cameras are A-1 and X-700.) I usually
>keep the Minolta camera in a complex rig for another purpose, so I believe
>the Canon lens would be much more convenient for me to use. However, the
>price of the FD lens is going up rapidly, so if I want to get it, I suppose
>I should get it soon. I believe both models come with extension tubes.
>
>Can anyone offer advice on or comparison of these two lenses?
>
>Thanks.
>John Roberts
>rob...@cmr.ncsl.nist.gov
I have the 100mm f4 Canon FD Macro lens, which I got about a year
ago and have done a fair amount of macro and non-macro work with it.
It is one sharp lens, at all distances. It is sold with a 50mm
extension tube, and instructions, including a little sticker with
an exposure compensation table (useful for flash or external
meters). I use it on an old-style F-1. Get it soon, the cost has
risen nearly $100 since I bought it. The one I got looked like it
had been sitting on a shelf for quite some time, but was in perfect
condition, so it may not be a lens that is selling well, or even in
stock anymore. At 1:2, the distance is 45cm (I think this is front
element to subject, but I havn't measured, maybe it's nodal point to
subject, which isn't much different with this non-tele design.) At
1:1, it's 40cm. To get from 1:2 to 1:1 the extension tube is
required. It isn't a tele design, so at infinity, 100mm from the
film plane is inside the lens, not in front of it, making this a
fairly large lens for its focal length, as compared to more modern
designs. It also focuses in the macro range the old fashioned way,
by extension, not by internal focusing like some modern lenses, so
it is 200mm long at 1:1, so have a sturdy tripod. The front element
is heavily recessed, so macro ring lights won't flare. This with a
hood (it takes the BT-52) makes for what should be a flare-proof
lens. I like it and am happy I got it before the price went up.
Drew
Paul Repacholi
> I've pretty much decided on a 100mm (non-zoom) macro for a non-autofocus
> Canon or Minolta (FD or MD). (The cameras are A-1 and X-700.) I usually
> keep the Minolta camera in a complex rig for another purpose, so I believe
> the Canon lens would be much more convenient for me to use. However, the
> price of the FD lens is going up rapidly, so if I want to get it, I suppose
> I should get it soon. I believe both models come with extension tubes.
I found the FD 200 f4 a better macro lens. It has better working distance and
doesn't need an extention tube to go to 1:1. The 100mm comes with a 50mm
extention tube. I nearly bought a 200 and adapter for my EOS, but descided
to wait and hope Canon brings it out in EF mount. BTW, the 200 f4 is discon-
tinued. The 50 and 100 macros are still current. The resolution of the 50 f3.5
is hard to beat. pity about the 3.5 though... I PERSONALY would rate the 100
behind the other 2, you can't use it as a standard lens, and it dosn't have
the working distance of the 200. This last point one to watch, if you are
working indoors with lights, the shadow from the lens/your head can be a real
pain in the neck. The 200 is also a nice tele with builtin lens hood.
~Paul
steve hix
>In article <920615180...@cmr.ncsl.nist.gov>, rob...@CMR.NCSL.NIST.GOV (John Roberts) writes:
>>
>> I could use some advice on a macro lens for a 35mm camera.
>...
>> I've pretty much decided on a 100mm (non-zoom) macro for a non-autofocus
>> Canon or Minolta (FD or MD). (The cameras are A-1 and X-700.) I usually
>> keep the Minolta camera in a complex rig for another purpose, so I believe
>> the Canon lens would be much more convenient for me to use. However, the
>> price of the FD lens is going up rapidly, so if I want to get it, I suppose
>> I should get it soon. I believe both models come with extension tubes.
>
>I found the FD 200 f4 a better macro lens. It has better working distance and
>doesn't need an extention tube to go to 1:1.
But at 1:1 it's effectively a 140mm lens. It's also bigger and heavier than
the 100, even with the extension tube.
> BTW, the 200 f4 is discontinued.
Too bad...
>The 50 and 100 macros are still current. The resolution of the 50 f3.5
>is hard to beat. pity about the 3.5 though... I PERSONALY would rate the 100
>behind the other 2, you can't use it as a standard lens, and it dosn't have
>the working distance of the 200.
But it makes a good portrait lens, is smaller/lighter than the 200...and I
think that I "see" in 100mm-equivalent. There are some field situations where
I literally can't get back far enough from the subject to use the 200...even
a few where the 50 is the only one that will let me get the picture, due to
things like bogs, rivers, large rocks, etc.
>This last point one to watch, if you are
>working indoors with lights, the shadow from the lens/your head can be a real
>pain in the neck.
This is often a problem outdoors with the 50, less so with the 100.
Between working distance constraints and real-world obstructions, I find that
I made a good decision to get all three: 50, 100, and 200mm macros. They each
have a place, and I use them all. But the 50 gets used the least (but enough
that I always try to haul it along), and the 100 turns out to be my "normal"
lens.
Several otherwise-attractive 35mm SLR systems were eliminated from my
consideration, btw, because they didn't offer a 200 mm macro lens. After
that, it was easy: I've never personally liked using Nikons much.
>The 200 is also a nice tele with builtin lens hood.
It works with the same Canon telexetender (2x-B) as that used by 300mm or
longer lenses. I think it's the only <300mm lens that is spec'd to use
that telextender. The other one (2x-A) is for <300mm lenses except for
the 200 macro.
--
-----------------------------------------------------------------------
Of making many books there is no end... | What's wrong with chasing
-- Eccl. 12:12 | nebulae till 3 am? |-(
-----------------------------------------------------------------------
John P. Gloria
The operative word here is "I". "I" happen to think the 100m
macro is great! Yes, the 200mm is great, but hand held at
1:1 vs the 100mm, I'd pick the 100mm. Besides, at 1:1 ratio,
there is no difference, is there, in the picture irregardless if
you use the 50, 100, or 200 macro. It appears to me though
that the 50mm seems to give "me" better of depth of field and is
better for flower, still life, and copy work. Yes, both models come
with extension tubes (25 & 50). The work distance for a 1:1 ratio
on the 100mm is approx. 8 inches and the 200 is about 10-12
inches (if memory serves me right), so there really isn't much
difference there. The 100mm is better suited for portrait work,
which I use alot when doing shoots (weddings, awards banquets,
etc.) You state pity about the f/3.5, what about the f/4/0 on
the 200. Come on, let's not be so biased. I have used both the
50mm and 100mm macro lenses (both Canon lenses) and they are
excellent. The 200mm is about 2-4 times the cost of the
50/100mm and based on this, I would opt for the 100mm.
BTW, you really don't need a lens hood on the Canon
macro lenses, afterall, the lenses are recessed quite far in
the barrel, which in essence does not require an additional
hood.
--
--------- John Gloria - jpg...@pacbell.com --------
"You cannot depend on your eyes when your imagination
is out of focus." - Mark Twain
steve hix
>
>The operative word here is "I". "I" happen to think the 100m
>macro is great! Yes, the 200mm is great, but hand held at
>1:1 vs the 100mm, I'd pick the 100mm. Besides, at 1:1 ratio,
>there is no difference, is there, in the picture irregardless if
>you use the 50, 100, or 200 macro.
Um...I think there is.
The *subject* is pretty much the same in all three cases, but the
background won't be. One reason to use a longer lens for a given
subject size on the film is to cut out some distracting background
element.
>It appears to me though
>that the 50mm seems to give "me" better of depth of field and is
>better for flower, still life, and copy work. Yes, both models come
>with extension tubes (25 & 50). The work distance for a 1:1 ratio
>on the 100mm is approx. 8 inches and the 200 is about 10-12
Partly because, since the 200 uses real-element movement for most
of its focusing, the focal length shortens as you move closer to
the subject. At 1:1 it's down to about 140mm.
>The 200mm is about 2-4 times the cost of the
>50/100mm and based on this, I would opt for the 100mm.
But there are some subjects that come out very well with the 200
that don't work at all with the 100 or 50.
Take a look at John Shaw's book on Close-up photography for some
examples.
That's why you *need* all *three* lenses!! :} 8} 8}
(As I told my wife sometime long ago...)
>BTW, you really don't need a lens hood on the Canon
>macro lenses, afterall, the lenses are recessed quite far in
>the barrel, which in essence does not require an additional
>hood.
The which is very nice...but a bit more don't hurt.
John P. Gloria
>In article <1992Jun17....@PacBell.COM> jpg...@srv.PacBell.COM (John P. Gloria) writes:
>>
>>The operative word here is "I". "I" happen to think the 100m
>>macro is great! Yes, the 200mm is great, but hand held at
>>1:1 vs the 100mm, I'd pick the 100mm. Besides, at 1:1 ratio,
>element.
>
Not the one to cause a riff here, but, when comparing *macro*
lenses you have to aware that inherently, they have a
somewhat shallow depth of field. I know you KNOW this.
This being established, the background can be thrown out of
focus quite simply with any of the aforemention lenses.
Think about.
>>It appears to me though
>>that the 50mm seems to give "me" better of depth of field and is
>>better for flower, still life, and copy work. Yes, both models come
>>with extension tubes (25 & 50). The work distance for a 1:1 ratio
>>on the 100mm is approx. 8 inches and the 200 is about 10-12
>
>Partly because, since the 200 uses real-element movement for most
>of its focusing, the focal length shortens as you move closer to
>the subject. At 1:1 it's down to about 140mm.
>
>>The 200mm is about 2-4 times the cost of the
>>50/100mm and based on this, I would opt for the 100mm.
>
>But there are some subjects that come out very well with the 200
>that don't work at all with the 100 or 50.
>
>Take a look at John Shaw's book on Close-up photography for some
>examples.
yet though.
>
>That's why you *need* all *three* lenses!! :} 8} 8}
>(As I told my wife sometime long ago...)
>
qualify your lenses. : ) BTW, I recently sold my 50 macro
because it was not being used. I use my 100mm macro alot
more than my other lenses when it comes to personal
photography. IMHO, the 100mm has more functionality than
the 200mm macro. I must admit though that the 200mm macro
will be my next lens to find, if I can find one (at a good
price). Have a nice evening/day/week.
steve hix
>In article <l3vppr...@appserv.Eng.Sun.COM> fid...@concertina.Eng.Sun.COM (steve hix) writes:
>>In article <1992Jun17....@PacBell.COM> jpg...@srv.PacBell.COM (John P. Gloria) writes:
>>
>Not the one to cause a riff here, but, when comparing *macro*
>lenses you have to aware that inherently, they have a
>somewhat shallow depth of field. I know you KNOW this.
A macro lens's depth of field is exactly the same as a non-macro
lens of the same focal length, at the same aperture, at the same
subject-to-film distance...the macro just gets in closer than
the standard lens before it gives up.
>This being established, the background can be thrown out of
>focus quite simply with any of the aforemention lenses.
OK. Don't forget, though, that a longer focal length lens will
take in a smaller angle of view, and so for a given subject size,
the longer lens will see less background. A bit of movement by
you can result in a given subject with widely-varying background
(out of focus though they be) visible in the finished picture.
>>But there are some subjects that come out very well with the 200
>>that don't work at all with the 100 or 50.
>>
>Name me five. :)
I'll just use one example. A russian thistle in the morning at the
edge of a meadow. I want the flower to fill 2/3 of the frame. The
thistle is nicely 3/4 backlit by the sun which has just come (mostly)
above the background trees.
With the 50, I get a chunk of sky, a chunk of background douglas fir,
and some background assorted flowers.
With the 100, most of the flowers are gone and most of the sky.
With the 200, none of the flowers show, the sky is gone, only the
(out of focus) dark green of the firs backs the thistle.
In the same morning shoot, I found some forget-me-nots next to some
skunk cabbage leaves. The one usable position for a low-angle shot
worked if I used the 50. Neither the 100 or 200 could fit in, because
of a large tree and a bunch of poison oak.
You use the tool what fits the job.
>>Take a look at John Shaw's book on Close-up photography for some
>>examples.
>I have Shaw's book. I have to admit I haven't read it all
>yet though.
It's worth taking the time. Gets me revved up again each spring...
>>That's why you *need* all *three* lenses!! :} 8} 8}
>>(As I told my wife sometime long ago...)
>>
>Are you trying to justify the expenditure to me or to
>qualify your lenses. : )
I already went through the justification process with the Boss...
>BTW, I recently sold my 50 macro because it was not being used.
So I loan it to my daughter one day when we go shooting. This would
be the time she decided to not come all the way to the falls...and one
great shot required shooting between two trees at the edge of a
small canyon across to the falls. The 24 is too wide unless I can
learn to hover, nothing longer than 50 would get it all.
>photography. IMHO, the 100mm has more functionality than
>the 200mm macro.
No contest.
There are times, though...
John P. Gloria
>In article <1992Jun18.0...@PacBell.COM> jpg...@srv.PacBell.COM (John P. Gloria) writes:
>>In article <l3vppr...@appserv.Eng.Sun.COM> fid...@concertina.Eng.Sun.COM (steve hix) writes:
>>>In article <1992Jun17....@PacBell.COM> jpg...@srv.PacBell.COM (John P. Gloria) writes:
>>>
>>Not the one to cause a riff here, but, when comparing *macro*
>>lenses you have to aware that inherently, they have a
>>somewhat shallow depth of field. I know you KNOW this.
>
>A macro lens's depth of field is exactly the same as a non-macro
>lens of the same focal length, at the same aperture, at the same
>subject-to-film distance...the macro just gets in closer than
>the standard lens before it gives up.
>
more specific. I was referring to 1:1 ratio. There is no way
that f/16 on a macro (1:1 ratio) will give the same depth-of-field
as a standard 50mm lens. I have taken quite a few macro
pictures and when you are 6 inches from a subject at 1:1 ratio,
there is definitely some differences in depth-of-field.
>>
>>>But there are some subjects that come out very well with the 200
>>>that don't work at all with the 100 or 50.
>>>
>>Name me five. :)
>
>I'll just use one example. A russian thistle in the morning at the
>edge of a meadow. I want the flower to fill 2/3 of the frame. The
>thistle is nicely 3/4 backlit by the sun which has just come (mostly)
>above the background trees.
>
>With the 50, I get a chunk of sky, a chunk of background douglas fir,
>and some background assorted flowers.
>
>With the 100, most of the flowers are gone and most of the sky.
>
>With the 200, none of the flowers show, the sky is gone, only the
>(out of focus) dark green of the firs backs the thistle.
>
without a comment or two. I know what you are trying to say
and you are right when using the lens in nonmacro mode, i.e.,
not using 1:1 ratio. However, the main or one of the main,
aspects of photography is composition. You or better yet, I,
could obtain the same results with either the 50mm or 100mm, simply
by composing and framing. How? You get a better angle, move
forward or backwards and you can basically get the same results. You
say you want the flower to fill 2/3 of the frame in your example.
I can get 2/3's with either the 50 or 100. Again, it is all a matter
of composition, as in get closer.
>
>In the same morning shoot, I found some forget-me-nots next to some
>skunk cabbage leaves. The one usable position for a low-angle shot
>worked if I used the 50. Neither the 100 or 200 could fit in, because
>of a large tree and a bunch of poison oak.
>
Well, I was not there, but I guess what you are saying is that
the subject was between a tree and some poison oak and the 50mm
was the best choice because using the 100mm would put back onto
the barriers? Again, I do not know if you were using your 50
macro as a standard lens or were you doing 1:2 or 1:1 ratios?
If you were using 1:2 or 1:1 ratios, I don't see how a few
inches would have made that much of a difference that would
have prevented using the 100 macro. Oh well.
steve hix
>In article <l41rc8...@appserv.Eng.Sun.COM> fid...@concertina.Eng.Sun.COM (steve hix) writes:
>>
>>A macro lens's depth of field is exactly the same as a non-macro
>>lens of the same focal length, at the same aperture, at the same
>>subject-to-film distance...the macro just gets in closer than
>>the standard lens before it gives up.
>>
>Maybe I am missing the boat here or the point. I should have been
>more specific. I was referring to 1:1 ratio. There is no way
>that f/16 on a macro (1:1 ratio) will give the same depth-of-field
>as a standard 50mm lens.
If you can focus down to a 1:1 ratio with a normal 50mm lens, the
depth of field with that lens will be exactly the same as the depth
of field of your 50mm macro focused to the same 1:1 ratio.
You'll have to use more extension on the normal lens (but only
because a macro usually has some of the needed extension built in
to its focusing mechanism.
The only difference will be that the results you get from the
normal lens won't be as good as those from the macro.
At the 1:1 image:subject ration, both will have the same depth of
field at the same f/stop.
>>I'll just use one example. A russian thistle in the morning at the
>>edge of a meadow. I want the flower to fill 2/3 of the frame. The
>>thistle is nicely 3/4 backlit by the sun which has just come (mostly)
>>above the background trees.
>>
>>With the 50, I get a chunk of sky, a chunk of background douglas fir,
>>and some background assorted flowers.
>>
>>With the 100, most of the flowers are gone and most of the sky.
>>
>>With the 200, none of the flowers show, the sky is gone, only the
>>(out of focus) dark green of the firs backs the thistle.
>>
>I don't know but I cannot really let your explanation go
>without a comment or two. I know what you are trying to say
>and you are right when using the lens in nonmacro mode, i.e.,
>not using 1:1 ratio.
There's no special "mode" involved! The technique of composing
don't care what the distance is. Things don't suddenly change at
some particular distance. If the flower was very small (unlike
the thistle), the same effects would apply, I'd just have to be
closer to the subject to get the same image size (and the background
would be more out of focus than it would be for the larger flower).
With the longer focal length lens, the angle of view is narrower,
and I might be able to control the background with a bit of lateral
movement, while with a shorter (wider angle) lens shooting at the
same image size it might well not be possible to get away from
some distracting background element at all.
>However, the main or one of the main,
>aspects of photography is composition. You or better yet, I,
>could obtain the same results with either the 50mm or 100mm, simply
>by composing and framing. How? You get a better angle, move
>forward or backwards and you can basically get the same results.
If you move closer or further away from the subject in the example
above...you just lost the specified 2/3 filling of the frame with
the subject. You're getting something different, maybe better,
maybe worse. But it ain't the same anymore.
If you use a shorter lens, you won't be able to cut the sky (or maybe
even the background flowers) out of the picture. It won't be the
same picture. It might well be a nice picture, but the effect would
have to be completely different. I want a backlighted thistle against
a dark, monochromatic background.
>You say you want the flower to fill 2/3 of the frame in your example.
>I can get 2/3's with either the 50 or 100. Again, it is all a matter
>of composition, as in get closer.
Of course you can!!! I never said you couldn't...but the pictures
taken by the two (or three, by now) different lenses will be different.
You use the tool you need to get the result you want, and not all tools
will give equivalent results. I'll not say worse, but certainly they
will be different results.
>>In the same morning shoot, I found some forget-me-nots next to some
>>skunk cabbage leaves. The one usable position for a low-angle shot
>>worked if I used the 50. Neither the 100 or 200 could fit in, because
>>of a large tree and a bunch of poison oak.
>>
>You have heard I am sure of the saying, "I guess you had to be there".
>Well, I was not there, but I guess what you are saying is that
>the subject was between a tree and some poison oak and the 50mm
>was the best choice because using the 100mm would put back onto
>the barriers? Again, I do not know if you were using your 50
>macro as a standard lens or were you doing 1:2 or 1:1 ratios?
>If you were using 1:2 or 1:1 ratios, I don't see how a few
>inches would have made that much of a difference that would
>have prevented using the 100 macro. Oh well.
It would have made a difference if the bloody lens couldn't physically
fit in the space available!
There's nothing magical in a 1:2 or 1:1 ratio, btw. (Technically,
that's not even macrophotography, not being a 'big picture'. Common
usage has taken a technical term and diluted it to mean 'pretty
close'.)
It is convenient to be able to get down that close, but very few
subjects call for anything in that particular range...but the
so-called macro lenses let us play in the range between 1:1 or
even 2: or 3:1 and the 18" or so that a standard 50mm lens can
focus down to.
David Jacobson
>In article <1992Jun18.0...@PacBell.COM> jpg...@srv.PacBell.COM (John P. Gloria) writes:
>>In article <l3vppr...@appserv.Eng.Sun.COM> fid...@concertina.Eng.Sun.COM (steve hix) writes:
>>>In article <1992Jun17....@PacBell.COM> jpg...@srv.PacBell.COM (John P. Gloria) writes:
>>>
>>Not the one to cause a riff here, but, when comparing *macro*
>>lenses you have to aware that inherently, they have a
>>somewhat shallow depth of field. I know you KNOW this.
>
>A macro lens's depth of field is exactly the same as a non-macro
>lens of the same focal length, at the same aperture, at the same
>subject-to-film distance...the macro just gets in closer than
>the standard lens before it gives up.
Actually, you could have made an even stronger statement: for macro
work a macro lens's depth of field is the same as *any* lens's depth
of field at the same aperture and magnification. Even switching
between 50, 100, and 200 mm macros doesn't effect the depth of field
as long as the subject fills the same part of the frame in all the
shots.
-- David Jacobson
David Jacobson
Recently I posted an article <1992Jun19....@cello.hpl.hp.com>
in which I claimed:
> For macro work a macro lens's depth of field is the same as *any*
> lens's depth of field at the same aperture and magnification. Even
> switching between 50, 100, and 200 mm macros doesn't effect the depth
> of field as long as the subject fills the same part of the frame in
> all the shots.
Well, I got to thinking about it and while this is true, it is not the
complete story. Consider the case of a 1:1 photograph at, say, f/16.
What I said was true since moving the subject back and forth a
millimeter also moves the image a millimeter (this is special for just
1:1) and thus the depth of field will be exactly the circle of
confusion times the f-stop for any focal length lens, specifically
.030 mm * 16 or .48 mm. (Indeed macro stuff has really small depth of
field.)
But consider how a point that is part of an object in the background
(say at infinity for simplicity) is rendered. The film is at distance
2F (F is the focal length) from the lens, and the point will be imaged
at 1F. So the light goes through the lens's diaphragm, through the
focal point, crosses over and makes a shape on the film exactly the same
size as the diaphragm. And at a consistent f stop (which has been my
assumption) a longer lens will have a larger diaphragm and thus the
out of focus point will be rendered as a larger circle. Specifically,
the point will be rendered as a 3.125mm circle by a 50mm lens, a
6.25mm circle by a 100mm lens, and a 12.5mm circle by a 200mm lens.
Here is a plot of circle diameter vs. distance beyond the subject for
a 50mm and a 100 mm macro lens.
diameter of
rendered point (mm)
# ==
# ============
5 # ============
# ======
# ====== 100mm lens
# ===
4 # ===
# =====
# ==
# ==
# ==
3 # == ********************
# = ******************
# == ************ 50mm lens
# = ***
# = ******
2 # = *
# = **
# = *
* # =*
= # =
=#*=
=#=
==
###==######################################################################
0 200 400 600 800 1000
distance behind subject (mm)
Very near the subject (0), the two curves lie on top of each other
(you can't see it in tty graphics, but they do). But at further
distances they depart considerably. Hmmmmm. Have any of you people
noticed this effect? (I've never had the luxury of having multiple
macro lenses.) Or are things just so much out of focus that it
doesn't matter?
-- David Jacobson
Tugrulbey Kiryaman
And like John P. Gloria, I think a 100mm macro lens is a most versatile and
useful lens. A 200mm macro is rather specialized, like Nikon's and Zeiss'
200mm Medical lenses. I find a 50-60mm macro unnecessary. Much rather prefer
a good wideangle with close-focus capability.
steve hix
>
>Recently I posted an article <1992Jun19....@cello.hpl.hp.com>
>in which I claimed:
>
>> For macro work a macro lens's depth of field is the same as *any*
>> lens's depth of field at the same aperture and magnification. Even
>> switching between 50, 100, and 200 mm macros doesn't effect the depth
>> of field as long as the subject fills the same part of the frame in
>> all the shots.
>
>Well, I got to thinking about it and while this is true, it is not the
>complete story. Consider the case of a 1:1 photograph at, say, f/16.
> [ comparison of increase in size of circle of confusion of points
beyond plane of focus of subject at 1:1 magnification for 50 and
100mm lenses. ]
>Very near the subject (0), the two curves lie on top of each other
>(you can't see it in tty graphics, but they do). But at further
>distances they depart considerably. Hmmmmm. Have any of you people
>noticed this effect? (I've never had the luxury of having multiple
>macro lenses.) Or are things just so much out of focus that it
>doesn't matter?
The effect is noticeable, but not hugely so.
It's useful to remember if you have a subject with a distracting background
to subdue. Assuming, of course, that the situation permits the luxury of
choosing a longer (or shorter) lens to get the subject.
Al Goldis
>I don't know but I cannot really let your explanation go
>without a comment or two. I know what you are trying to say
>and you are right when using the lens in nonmacro mode, i.e.,
>not using 1:1 ratio. However, the main or one of the main,
>aspects of photography is composition. You or better yet, I,
>could obtain the same results with either the 50mm or 100mm, simply
>by composing and framing. How? You get a better angle, move
>forward or backwards and you can basically get the same results. You
>say you want the flower to fill 2/3 of the frame in your example.
>I can get 2/3's with either the 50 or 100. Again, it is all a matter
>of composition, as in get closer.
No, there's more to it than filling the frame with your subject.
Between a 50mm and 200mm lens (macro or not) there is quite a bit of
difference in angle of view. (I'm going to totally ignore depth of
field for a moment.) Assuming you have the freedom to move anywhere
you want, you can get the flower to fill 2/3 of the frame, but that
doesn't mean the picture will look the same. The background will be
considerably different, not to mention the overall perspective.
It's not as obvious when we're talking about the difference between a
50mm and 100m lens. So to illustrate, think about a more extreme
example. Take pictures of a person's face with two lenses--a 20mm and
a 600mm. With both lenses, make their face fill 2/3 of the frame.
That means their nose will only be about 4 inches away from the front
of the 20mm but with the 600mm they will be about 25 feet away.
Now some things start to happen. The 20mm has an angle of view of
approximately 94 degrees while the 600mm covers only about 4 degrees.
How much background is included in the two shots? The 20mm shows lots
of background; the sky, trees, buildings, the ground, etc.. The 600mm
only shows a small part of the wall on the building across the street.
Perspective is totally different. With the 20mm their face looks
distorted. Technically, I suppose you could say it is not distorted,
but it sure looks that way. With the compression of the 600mm their
face looks rather flat and two-dimensional. Why? Relative distance.
With the 20mm the distance to their nose is only 4 inches. The
distance from their nose to their ears is almost another 4 inches.
Relative to the distance from the lens, the distance between their
facial features is very significant. So the big difference in
relative size of facial features creates the appearance of the big
nose and bulging face.
In contrast, with the 600mm, the distance to their nose is 25 feet or
150 inches. Now the 4 inch distance from their nose to ears is
insignificant.
So this focal length/angle of view business can be very important in
determining how a subject looks. In the example of taking a picture
of something as simple as a single flower--aside from the big
difference in backgrounds--even the flower itself can look very
different.
--
Al Goldis gol...@umaxc.weeg.uiowa.edu
"Pictures are moments truth, touched by light, that show character."
--Annie Griffiths-Belt
Al Goldis
> In contrast, with the 600mm, the distance to their nose is 25 feet or
> 150 inches. Now the 4 inch distance from their nose to ears is
Oops. Last time I checked there were still 12 inches in a foot. Make
that 300 inches. ;-)
John P. Gloria
>In <1992Jun18....@PacBell.COM> jpg...@srv.PacBell.COM (John P. Gloria) writes:
>>I don't know but I cannot really let your explanation go
>>without a comment or two. I know what you are trying to say
>>and you are right when using the lens in nonmacro mode, i.e.,
>>not using 1:1 ratio. However, the main or one of the main,
>>aspects of photography is composition. You or better yet, I,
>>could obtain the same results with either the 50mm or 100mm, simply
>>by composing and framing. How? You get a better angle, move
>>forward or backwards and you can basically get the same results. You
>>say you want the flower to fill 2/3 of the frame in your example.
>>I can get 2/3's with either the 50 or 100. Again, it is all a matter
>>of composition, as in get closer.
>
>No, there's more to it than filling the frame with your subject.
>Between a 50mm and 200mm lens (macro or not) there is quite a bit of
>difference in angle of view. (I'm going to totally ignore depth of
>field for a moment.) Assuming you have the freedom to move anywhere
>you want, you can get the flower to fill 2/3 of the frame, but that
>doesn't mean the picture will look the same. The background will be
>considerably different, not to mention the overall perspective.
>
yet you write later that the background will be considerably
different. Explain, if it is not depth of field.
>
>It's not as obvious when we're talking about the difference between a
>50mm and 100m lens. So to illustrate, think about a more extreme
>example. Take pictures of a person's face with two lenses--a 20mm and
>a 600mm. With both lenses, make their face fill 2/3 of the frame.
>That means their nose will only be about 4 inches away from the front
>of the 20mm but with the 600mm they will be about 25 feet away.
>
Now you are comparing from one extreme to another. I know what you
are illustrating. Let me put it this way. Set-up: two 35mm SLRs;
one camera has a 50mm non macro lens; camera no. 2 has a 100mm
no macro lens; subject is a basketball on a pedestal. Camera
one fills frame with basketball, approx. 2/3 of frame. Camera
two does the same. The key word I used on my original post
(above) was "basically". I.e. both pictures in this setup will
basically look the same, not exactly. If the aperture on
camera two is set to f/22 and camera one to f/8, there will be
some difference, but basically the same picture.
>Now some things start to happen. The 20mm has an angle of view of
>approximately 94 degrees while the 600mm covers only about 4 degrees.
>How much background is included in the two shots? The 20mm shows lots
>of background; the sky, trees, buildings, the ground, etc.. The 600mm
>only shows a small part of the wall on the building across the street.
>
>Perspective is totally different. With the 20mm their face looks
>distorted. Technically, I suppose you could say it is not distorted,
>but it sure looks that way. With the compression of the 600mm their
>face looks rather flat and two-dimensional. Why? Relative distance.
>
>With the 20mm the distance to their nose is only 4 inches. The
>distance from their nose to their ears is almost another 4 inches.
>Relative to the distance from the lens, the distance between their
>facial features is very significant. So the big difference in
>relative size of facial features creates the appearance of the big
>nose and bulging face.
>
>In contrast, with the 600mm, the distance to their nose is 25 feet or
>150 inches. Now the 4 inch distance from their nose to ears is
>insignificant.
>
>So this focal length/angle of view business can be very important in
>determining how a subject looks. In the example of taking a picture
>of something as simple as a single flower--aside from the big
>difference in backgrounds--even the flower itself can look very
>different.
>--
I guess I am being too picky on my point. You are correct in your
summations above. However, I was not comparing a 20mm lens versus
a 600mm lens, just a 50mm and 100mm lens.
steve hix
>In article <1992Jun29.1...@news.weeg.uiowa.edu> gol...@news.weeg.uiowa.edu (Al Goldis) writes:
>>
>>No, there's more to it than filling the frame with your subject.
>>Between a 50mm and 200mm lens (macro or not) there is quite a bit of
>>difference in angle of view. (I'm going to totally ignore depth of
>>field for a moment.) Assuming you have the freedom to move anywhere
>>you want, you can get the flower to fill 2/3 of the frame, but that
>>doesn't mean the picture will look the same. The background will be
>>considerably different, not to mention the overall perspective.
>>
>You write you will totally ignore depth of field for a moment,
>yet you write later that the background will be considerably
>different. Explain, if it is not depth of field.
It's that other thing that Al was talking about: angle of view.
A 200mm lens has an angle of view of, what, 12 degrees? And the 50mm
has about 47 degrees or so?
You've moved yourself so that the subject takes up 2/3 of the frame
with either lens. The 50mm background will include the whole lineup
of the family behind the holiday roast you're shooting. (They're out
of focus, but you're not worried.) This fuzzy background will include
the puce, magenta, and orange worn by your younger cousins at either end of
the line. Undesirable...
So you switch to the 200mm, and compose the roast to your desired 2/3
of the frame. Note the (fuzzier than ever) background: no more puce,
magenta, and orange from your three cousins named Ashleigh...all you
have in the field are the muted earth tones worn by your grandparents and
great-uncle Oswald.
Different backgrounds.
>That was my whole point, specificially, a 50mm and 100m lens.
IF you went to the 100mm instead of the 200mm, then you'd get your
parents and maybe an uncle or two in the background, fuzzier than the
50mm, but not as much as the 200mm. Still no cousins named Ashleigh.
>Now you are comparing from one extreme to another. I know what you
>are illustrating. Let me put it this way. Set-up: two 35mm SLRs;
>one camera has a 50mm non macro lens; camera no. 2 has a 100mm
>no macro lens; subject is a basketball on a pedestal. Camera
>one fills frame with basketball, approx. 2/3 of frame. Camera
>two does the same. The key word I used on my original post
>(above) was "basically". I.e. both pictures in this setup will
>basically look the same, not exactly. If the aperture on
>camera two is set to f/22 and camera one to f/8, there will be
>some difference, but basically the same picture.
The foreground subject will be similar, but you're still going to be
dealing with about half the background ending up in the picture.
I'd say that the picture would be noticeably different. (Of course,
the background in either shot *could* be a featureless green, but
with Murphy runnign around loose, you can't always assume a best-
case situation.)