Newbie question about macro with DSLR

Newbie question about macro with DSLR

I'm considering buying a Canon Digital Rebel XSi for a project involving
macro photography, and I'm looking for advice regarding macro lenses,
reverse mounts, etc.

Basically I'm trying to photograph a flat subject such that an area
about 1 mm on a side will be full-frame. It would be better yet if
I could do that for an area 0.5 mm on a side.

The camera has an APS-C size sensor (22.2 x 14.8 mm).

I have a precision X-Y stage with stepper motors and microstepping
control, so I can position the subject in increments of less than
0.1 mm. I plan to take many photos with a small shift, and stitch them
together, probably using Hugin. Because I expect there to be a lot of
overlap between the images, I think I can tolerate some amount of
vignetting, spherical abberation, etc.

Is this feasible with some macro lens, combination of lenses, reversing
ring, extension tube, etc?

I'm hoping to avoid the need to buy a microscope and adapter, due to
the cost, though that's obviously an option. I'm not sure how to tell
whether a particular microscope would be suitable without trying it;
for instance, I've looked at a 7x-90x microscope, but apparently 10x
or 20x of that magnification is due to the magnification of the
eyepiece, which I wouldn't have with the camera adapter.

Any advice would be greatly appreciated!

Thanks!
Eric

Re: Newbie question about macro with DSLR

I don't think you are going to get what you want with a macro lens.
This calls for a micro lens or being microscope adapter. Both of those are
outside my experience and need so I don't have much personal experience to
base any additional help. Sorry.

"Eric Smith" <eric@brouhaha,com > wrote in message
news:m3wsmionuw.fsf@donnybrook.brouhaha,com ...
> I'm considering buying a Canon Digital Rebel XSi for a project involving
> macro photography, and I'm looking for advice regarding macro lenses,
> reverse mounts, etc.
>
> Basically I'm trying to photograph a flat subject such that an area
> about 1 mm on a side will be full-frame. It would be better yet if
> I could do that for an area 0.5 mm on a side.
>
> The camera has an APS-C size sensor (22.2 x 14.8 mm).
>
> I have a precision X-Y stage with stepper motors and microstepping
> control, so I can position the subject in increments of less than
> 0.1 mm. I plan to take many photos with a small shift, and stitch them
> together, probably using Hugin. Because I expect there to be a lot of
> overlap between the images, I think I can tolerate some amount of
> vignetting, spherical abberation, etc.
>
> Is this feasible with some macro lens, combination of lenses, reversing
> ring, extension tube, etc?
>
> I'm hoping to avoid the need to buy a microscope and adapter, due to
> the cost, though that's obviously an option. I'm not sure how to tell
> whether a particular microscope would be suitable without trying it;
> for instance, I've looked at a 7x-90x microscope, but apparently 10x
> or 20x of that magnification is due to the magnification of the
> eyepiece, which I wouldn't have with the camera adapter.
>
> Any advice would be greatly appreciated!
>
> Thanks!
> Eric
>


--
Joseph Meehan

Dia 's Muire duit

Re: Newbie question about macro with DSLR

Joseph Meehan wrote:
> I don't think you are going to get what you want with a macro
> lens. This calls for a micro lens

This is the first I've heard of a "micro lens", so I did a Google search.
I did turn up one page saying that a micro lens was necessary for 10x or
higher magnification, but all the product pages I found were for Nikon
Micro-Nikkor lenses, and the specifications for those seemed comparable
to other vendors' macro lenses.

After a bit more searching, I found references to the discontinued
Raynox CM-3500 macro/closeup lens set, which includes 6x, 12x, and 24x
lenses:
http :// www .raynox.co.jp/english/egindex.htm

Apparently these are intended for use with telephoto lenses. If I can
find a set, perhaps this might do what I want? I'm not sure.

Thanks!
Eric

Re: Newbie question about macro with DSLR

Eric Smith <eric@brouhaha,com > wrote:
>This is the first I've heard of a "micro lens", so I did a Google search.
>I did turn up one page saying that a micro lens was necessary for 10x or
>higher magnification, but all the product pages I found were for Nikon
>Micro-Nikkor lenses, and the specifications for those seemed comparable
>to other vendors' macro lenses.

Yeah, for whatever reason Nikon calls "Micro" what everyone else calls
"Macro".

>After a bit more searching, I found references to the discontinued
>Raynox CM-3500 macro/closeup lens set, which includes 6x, 12x, and 24x
>lenses:
> http :// www .raynox.co.jp/english/egindex.htm

That page opens a whole slew of product, not sure which on in particular
you are referring to. Anyway, I suppose those are those add-on lenses,
that you screw into the the filter threads.

>Apparently these are intended for use with telephoto lenses.

The screw-on type can be used with any lens, not only telephoto.

>If I can
>find a set, perhaps this might do what I want? I'm not sure.

They are available from many different manufacturers for little money.
However I doubt that you will find any that will give you any decent
picture quality at the magnification you are looking for.

jue

Re: Newbie question about macro with DSLR

"Jürgen Exner" <jurgenex@hotmail,com > wrote in message
news:acjc14ppic294iiu7mqlmnl38ao8jrlq6p@4ax,com ...
...
>
> Yeah, for whatever reason Nikon calls "Micro" what everyone else calls
> "Macro".
>

Yea. Frankly everyone else is wrong, :-0 Well Nikon is wrong in their
use from time to time as well. I don't think it is going to get
straightened out, but it is good to keep in mind that there are two terms
and that we should all expect them to be used properly and improperly so we
don't assume that they will be used in the manner we expect.

--
Joseph Meehan

Dia 's Muire duit

Re: Newbie question about macro with DSLR

Joseph Meehan wrote:
> "Jürgen Exner" <jurgenex@hotmail,com > wrote in message
> news:acjc14ppic294iiu7mqlmnl38ao8jrlq6p@4ax,com ...
> ...
>>
>> Yeah, for whatever reason Nikon calls "Micro" what everyone else calls
>> "Macro".
>>
>
> Yea. Frankly everyone else is wrong, :-0 Well Nikon is wrong in
> their use from time to time as well. I don't think it is going to get
> straightened out, but it is good to keep in mind that there are two
> terms and that we should all expect them to be used properly and
> improperly so we don't assume that they will be used in the manner we
> expect.

Nikon calls them micro because they already used macro for an obscure
old line of extreme closeup lenses:
http :// www .naturfotograf,com /lens spec.html

Re: Newbie question about macro with DSLR


"Eric Smith" <eric@brouhaha,com > wrote in message
news:m3wsmionuw.fsf@donnybrook.brouhaha,com ...
> I'm considering buying a Canon Digital Rebel XSi for a project involving
> macro photography, and I'm looking for advice regarding macro lenses,
> reverse mounts, etc.
>
> Basically I'm trying to photograph a flat subject such that an area
> about 1 mm on a side will be full-frame. It would be better yet if
> I could do that for an area 0.5 mm on a side.

I don't think you will be happy with macro in this instance. Macro is good
for a "magnification" of 1x to 5x and my be able to go to 10x with some
aberation around the edges. At this mag factor the DOF is so tight that the
difference between the distance from the center of the lens to the subject
and the distance from the lens to the side of the subject would be more than
the DOF and so either the center of the image would be in focus or the edge,
not both.

So your need of making .5 to 1 mm full frame would be almost impossible and
so badly formed that you may get only a few clear pixels in the center of
the image. For the level of magnification you are looking for you would be
better off going with a microscope and adapter. Even then you may have
problems with flat focus. You may have to center the subject in the image
and crop the out of focus edges before attempting the stitching.

Good luck

Randy

Re: Newbie question about macro with DSLR

Randy Berbaum wrote:
> "Eric Smith" <eric@brouhaha,com > wrote in message
> news:m3wsmionuw.fsf@donnybrook.brouhaha,com ...
>> I'm considering buying a Canon Digital Rebel XSi for a project involving
>> macro photography, and I'm looking for advice regarding macro lenses,
>> reverse mounts, etc.
>>
>> Basically I'm trying to photograph a flat subject such that an area
>> about 1 mm on a side will be full-frame. It would be better yet if
>> I could do that for an area 0.5 mm on a side.
>
> I don't think you will be happy with macro in this instance. Macro is good
> for a "magnification" of 1x to 5x and my be able to go to 10x with some
> aberation around the edges. At this mag factor the DOF is so tight that the
> difference between the distance from the center of the lens to the subject
> and the distance from the lens to the side of the subject would be more than
> the DOF and so either the center of the image would be in focus or the edge,
> not both.
>
> So your need of making .5 to 1 mm full frame would be almost impossible and
> so badly formed that you may get only a few clear pixels in the center of
> the image. For the level of magnification you are looking for you would be
> better off going with a microscope and adapter. Even then you may have
> problems with flat focus. You may have to center the subject in the image
> and crop the out of focus edges before attempting the stitching.

This sounds right. A typical macro lens gets to 1:1 and 1mm is 1/18 of
that size (for the height).

On the other hand, how much detail do you need? If cropping, it is pixel
counts that'll tell you what magnification you need. The height (short
side) of a 10MP DSLR is about 2,500 pixels. For a really sharp print,
figure 300 pixels per inch. That will show usable detail for people with
perfect vision but you can easily double that size & still look fine
(150ppi).

Re: Newbie question about macro with DSLR

Paul Furman <paul-@-edgehill,net > writes:
> On the other hand, how much detail do you need?

I'd like to resolve details with a minimum feature size of 3 microns.
That's how I came up with the requirement to magnify 1 mm of the subject
to full-frame of a 10MP camera.

I would eventually like to produce very large prints, e.g. a 60 inch
wide print of a 10 mm wide subject, using something like an HP Designjet
8000 or 9000 series printer, but my initial objective is just to produce
files for viewing on a computer. Those would be about 10,000 pixels on a
side (300MB uncompressed at 24 bits per pixel).

Thanks,
Eric

Re: Newbie question about macro with DSLR

Eric Smith <eric@brouhaha,com > wrote:
>Paul Furman <paul-@-edgehill,net > writes:
>> On the other hand, how much detail do you need?
>
>I'd like to resolve details with a minimum feature size of 3 microns.

Defininately use a microscope with a camera adapter.

jue

Re: Newbie question about macro with DSLR

Jürgen Exner wrote:
> Eric Smith <eric@brouhaha,com > wrote:
>> Paul Furman <paul-@-edgehill,net > writes:
>>> On the other hand, how much detail do you need?
>> I'd like to resolve details with a minimum feature size of 3 microns.
>
> Defininately use a microscope with a camera adapter.
>
> jue

He does NOT need a microscope ... only a microscope objective
and some way to focus it.

As to focusing a microscope objective: the manufacturer specifies the
back focus ... that is, the distance from the mounting screw to were the
focal plane of the camera is. You just make sure that that distance is
about right, like within 5 mm. Then you focus by moving the subject, or
by small movement of the objective.

Doug McDonald

Re: Newbie question about macro with DSLR

user@domain.invalid wrote:
>Jürgen Exner wrote:
>> Eric Smith <eric@brouhaha,com > wrote:
>>> Paul Furman <paul-@-edgehill,net > writes:
>>>> On the other hand, how much detail do you need?
>>> I'd like to resolve details with a minimum feature size of 3 microns.
>> Defininately use a microscope with a camera adapter.
>> jue
>
>He does NOT need a microscope ... only a microscope objective
>and some way to focus it.

He needs a microscope. In addition to the objective and
focusing mechanism, he needs a "projection" (aka
"relay") lense appropriate for the sensor size.

One additional feature that would be nice is episcopic
illumination.

--
Floyd L. Davidson < http :// www .apaflo,com /floyd davidson>
Ukpeagvik (Barrow, Alaska) floyd@apaflo,com

Re: Newbie question about macro with DSLR

On Mon, 28 Apr 2008 20:21:15 -0800, floyd@apaflo,com (Floyd L.
Davidson) wrote:

>user@domain.invalid wrote:
>>Jürgen Exner wrote:
>>> Eric Smith <eric@brouhaha,com > wrote:
>>>> Paul Furman <paul-@-edgehill,net > writes:
>>>>> On the other hand, how much detail do you need?
>>>> I'd like to resolve details with a minimum feature size of 3 microns.
>>> Defininately use a microscope with a camera adapter.
>>> jue
>>
>>He does NOT need a microscope ... only a microscope objective
>>and some way to focus it.
>
>He needs a microscope. In addition to the objective and
>focusing mechanism , he needs a "projection" (aka
>"relay") lense appropriate for the sensor size.

I'm still trying to figure out what you mean by a "relay lens".
Projection is done with a prism and not with a lens. A beam splitter
projects the optical view by bending it with the prism. The type of
prism, and the distance between the prism and the sensor, determines
what the sensor records.

>One additional feature that would be nice is episcopic
>illumination.

OK, I figured this out. You are evidently talking about light
projected from above the field as opposed to light projected from
below the field. I have no idea why you want to call it "episcopic",
though. "From above" works fine.

Some lab microscopes have illuminated stages (light from below) so the
light illuminates the material on the slide. Some have light
projected down to the stage from either a coaxial system or fiber
optic ring light. Some use both.

If his object - the thing he's photographing - is opaque, he *must*
have light from above. Not "nice", but essential.


--
Tony Cooper - Orlando, Florida

Re: Newbie question about macro with DSLR

Randy Berbaum wrote:
> "Eric Smith" <eric@brouhaha,com > wrote in message
> news:m3wsmionuw.fsf@donnybrook.brouhaha,com ...
>> I'm considering buying a Canon Digital Rebel XSi for a project involving
>> macro photography, and I'm looking for advice regarding macro lenses,
>> reverse mounts, etc.
>>
>> Basically I'm trying to photograph a flat subject such that an area
>> about 1 mm on a side will be full-frame. It would be better yet if
>> I could do that for an area 0.5 mm on a side.
>
> I don't think you will be happy with macro in this instance. Macro is good
> for a "magnification" of 1x to 5x and my be able to go to 10x with some
> aberation around the edges. At this mag factor the DOF is so tight that the
> difference between the distance from the center of the lens to the subject
> and the distance from the lens to the side of the subject would be more than
> the DOF and so either the center of the image would be in focus or the edge,
> not both.
>
> So your need of making .5 to 1 mm full frame would be almost impossible and
> so badly formed that you may get only a few clear pixels in the center of
> the image. For the level of magnification you are looking for you would be
> better off going with a microscope and adapter. Even then you may have
> problems with flat focus.


The OP needs a microscope objective. With a good one flat field is
no problem. He needs a 20 or 40x one for best results. I am assuming
a truly flat subject where no depth of field is needed. It DOF
is needed, then the only hope is "slices" added up in software.

Remember that at 20x magnification, at f/1 AT THE SUBJECT
you get f/20 AT THE SENSOR. F/1 or even f/0.8 is available
in microscope objectives he can use. F/0.35 is available but
useless for his application (works only in oil!). Those are at the subject.

This is a specialized application. HE does NOT want an microscope since
he already has the stepper motor setup, he just need the objective
and some sort of illumination system. Olympus makes, or at least used to make,
the best equipment for this.

NOTE: some newer objectives are not designed to focus down on the
output side and need a "tube lens". These may have inacceptable
lateral chromatic if used without the manufacturer's tube lens.


Doug McDonald

Re: Newbie question about macro with DSLR

Doug McDonald wrote:
> The OP needs a microscope objective. With a good one flat field is
> no problem. He needs a 20 or 40x one for best results. I am assuming
> a truly flat subject where no depth of field is needed.

I think the surface of the subject should be flat to within better than
2 microns. What may be tricky is leveling it relative to the camera.

If I buy an objective lens for a microscope, do you have any recommendations
as to mounting it? How do I determine how far from the sensor it should be
mounted? (Maybe I need to go back to school to study optics!)

> he just need the objective
> and some sort of illumination system. Olympus makes, or at least used to make,
> the best equipment for this.

I've looked at the Olympus site, and am somewhat lost. If it's not too
much trouble, can you give me any more specific idea as to what I'm looking
for?

Thanks!
Eric