Hi,
As that`s my first topic lets start with a small introduction.
I`m a passionate mineral collector, especially so called micromounts. These are tiny crystalls +/- 1 mm which are mounted in a box.
I`ve been photographing these crystalls now for many years. You can see some at http://www.mindat.org/user-9684.html#2
Used different scopes like the Wild M8 or the Wild M420 (photomacroscope with apozoom).
Nevertheless when I compare scope pics with a bellow method, the later always seems better.
So I want to try also a bellow system, but don`t have any experience with it.
Crystalls +/- 1 mm, FOV 1-5 mm, I`m a Nikon fan.
What would you recommend?
Thanks in advance!
Microscope vs. bellow
Moderators: rjlittlefield, ChrisR, Chris S., Pau
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Charles Krebs
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oro,
Welcome.
The M420 with ApoZoom was a "dream" outfit (but unaffordable) for me many years ago.
A few thoughts....
You say you want "FOV 1-5mm". (I assume you mean the longer distance across the frame).
So with a smaller frame Nikon DSLR that would mean a magnification range from 4.8 to 24X
On a "full-frame" body that would mean a magnification range range from 7.2 to 36X
For much of this range, I have no doubt that a good microscope objective on bellows would out-perform the Wild ApoZoom.
My understanding is that the ApoZoom NA is 0.116. (With the Wild 2X attachment, the NA was 0.232... according to Betty here).
Based on this, I would expect the ApoZoom to be excellent and "competitive" with a bellows arrangement up to about 5 or 6X (magnification on sensor) with no attachments, and up to about 10X with the 2X attached. (A little higher with the full frame).
Above these magnifications the higher relative NA possible (for a given magnification) can potentially offer noticeably better resolution. Keep in mind that stacking becomes nearly essential. Also remember that microscope objectives just barely "cover" the smaller sized sensors, so if you want to use a full frame camera (24x36mm) edge performance will fall off and must be carefully tested and scrutinized.
Welcome.
The M420 with ApoZoom was a "dream" outfit (but unaffordable) for me many years ago.
I'd be curious to learn what lenses and magnifications were used on the shots you compared.Nevertheless when I compare scope pics with a bellow method, the later always seems better.
A few thoughts....
You say you want "FOV 1-5mm". (I assume you mean the longer distance across the frame).
So with a smaller frame Nikon DSLR that would mean a magnification range from 4.8 to 24X
On a "full-frame" body that would mean a magnification range range from 7.2 to 36X
For much of this range, I have no doubt that a good microscope objective on bellows would out-perform the Wild ApoZoom.
My understanding is that the ApoZoom NA is 0.116. (With the Wild 2X attachment, the NA was 0.232... according to Betty here).
Based on this, I would expect the ApoZoom to be excellent and "competitive" with a bellows arrangement up to about 5 or 6X (magnification on sensor) with no attachments, and up to about 10X with the 2X attached. (A little higher with the full frame).
Above these magnifications the higher relative NA possible (for a given magnification) can potentially offer noticeably better resolution. Keep in mind that stacking becomes nearly essential. Also remember that microscope objectives just barely "cover" the smaller sized sensors, so if you want to use a full frame camera (24x36mm) edge performance will fall off and must be carefully tested and scrutinized.
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rjlittlefield
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oro, welcome aboard! 
I share Charles' curiosity about the images posted on the page you link. In general these seem pretty soft compared to what should be produced by a high end scope.
However, I too am fond of bellows setups, and since you are asking specifically about those...
I suggest to start with an old enlarging lens, EL Nikkor 50 mm f/2.8, reversed on bellows. These lenses are widely available on eBay for around $50, cheaper if you catch a good deal. Be sure to avoid the 50 mm f/4 version -- that is a different design, much less sharp.
For bellows, it is better to get one where both ends slide on the rails. With many units, only the front slides. These are certainly usable, but sometimes less convenient because the rails sticking out the front can get in the way. (Of course when that happens, you might swap out the bellows for extension tubes anyway.) I am not intimate with Nikon bellows, but it looks to me like the PB-4 has what you need and is available at reasonable cost.
To mate the EL Nikkor lens with the bellows, you will need a Nikon reversing ring to fit the bellows, and a step ring (40.5 mm?) to fit the front thread of the lens.
Be sure to test what aperture setting gives the sharpest images. Typically it is around f/4-5.6.
The reversed EL Nikkor will generate excellent images out to about 5X on sensor. Beyond that, some improvement can be made by switching to a wider aperture and shorter focal length macro lens. Or more dramatic improvement can be made by switching to a microscope objective.
My recommendation for the next step would be jump to a microscope objective. You will need one of the "finite" designs, intended for use in a compound microscope with just the objective and an eyepiece, separated by a 160 mm or 210 mm tube.
The best of these are Nikon CF objectives, such as the Nikon CF N Plan Achromat 10X NA 0.30 that you will see referenced in many postings here at photomacrography.net. Those are available only as used, since Nikon microscopes now use "infinity" designs that are more suitable for adding attachments but require an additional "tube lens" in order to make good images.
However, one line of finite design objectives is still being manufactured by Nikon and is available new from Edmund Optics. These are the "Nikon Achromatic Finite Conjugate Objectives", HERE. I have tested one sample of the 10X NA 0.25 and found it to be surprisingly good, usable even down to about 7X on a 1.6 crop factor camera. See that report HERE. I have not tested the 4X, but that seems like another reasonable candidate to check out.
To fit microscope objectives to a bellows, you will need an RMS-to-M42 adapter and an M42-to-Nikon adapter. These are available as new manufacture parts on eBay, for example HERE and HERE. Be sure to get the M42-to-Nikon adapter without glass -- just the mechanical fitting.
--Rik
I share Charles' curiosity about the images posted on the page you link. In general these seem pretty soft compared to what should be produced by a high end scope.
However, I too am fond of bellows setups, and since you are asking specifically about those...
I suggest to start with an old enlarging lens, EL Nikkor 50 mm f/2.8, reversed on bellows. These lenses are widely available on eBay for around $50, cheaper if you catch a good deal. Be sure to avoid the 50 mm f/4 version -- that is a different design, much less sharp.
For bellows, it is better to get one where both ends slide on the rails. With many units, only the front slides. These are certainly usable, but sometimes less convenient because the rails sticking out the front can get in the way. (Of course when that happens, you might swap out the bellows for extension tubes anyway.) I am not intimate with Nikon bellows, but it looks to me like the PB-4 has what you need and is available at reasonable cost.
To mate the EL Nikkor lens with the bellows, you will need a Nikon reversing ring to fit the bellows, and a step ring (40.5 mm?) to fit the front thread of the lens.
Be sure to test what aperture setting gives the sharpest images. Typically it is around f/4-5.6.
The reversed EL Nikkor will generate excellent images out to about 5X on sensor. Beyond that, some improvement can be made by switching to a wider aperture and shorter focal length macro lens. Or more dramatic improvement can be made by switching to a microscope objective.
My recommendation for the next step would be jump to a microscope objective. You will need one of the "finite" designs, intended for use in a compound microscope with just the objective and an eyepiece, separated by a 160 mm or 210 mm tube.
The best of these are Nikon CF objectives, such as the Nikon CF N Plan Achromat 10X NA 0.30 that you will see referenced in many postings here at photomacrography.net. Those are available only as used, since Nikon microscopes now use "infinity" designs that are more suitable for adding attachments but require an additional "tube lens" in order to make good images.
However, one line of finite design objectives is still being manufactured by Nikon and is available new from Edmund Optics. These are the "Nikon Achromatic Finite Conjugate Objectives", HERE. I have tested one sample of the 10X NA 0.25 and found it to be surprisingly good, usable even down to about 7X on a 1.6 crop factor camera. See that report HERE. I have not tested the 4X, but that seems like another reasonable candidate to check out.
To fit microscope objectives to a bellows, you will need an RMS-to-M42 adapter and an M42-to-Nikon adapter. These are available as new manufacture parts on eBay, for example HERE and HERE. Be sure to get the M42-to-Nikon adapter without glass -- just the mechanical fitting.
--Rik
Greeting oro!
The M420 Apozoom is still my favorite outfit and I have lots of other goodies too. (and am generally a Nikon user too.)
One thing you didn't tell us. How are you coupling your camera to the M420.
This is a cat that there are many many ways to skin and some methods yield better results than others. And what kind of camera is it? Although presumably you are using the same camera in both settings.
Also are you sure you were using it to its maximum NA. Doing so pretty much dictates stacking or scanning light photography.
Are you comparing apples to apples as well.
The M420 Apozoom is still my favorite outfit and I have lots of other goodies too. (and am generally a Nikon user too.)
One thing you didn't tell us. How are you coupling your camera to the M420.
This is a cat that there are many many ways to skin and some methods yield better results than others. And what kind of camera is it? Although presumably you are using the same camera in both settings.
Also are you sure you were using it to its maximum NA. Doing so pretty much dictates stacking or scanning light photography.
Are you comparing apples to apples as well.
Thanks for your input, its really appreciated.
I thought I`ll add some pics to show you my system.
I`ve got the M420 with apozoom, use a Nikon D70 fixed with an adapter; use the highest JPEG setting, a SCHOTT KL1500 coldlight fibrearm, the camera is linked to a laptop, I use stacking software of Zerene.
The last pic shows a self built tool to hold the specimen. Its like a small cross table but without any possibility of measuring to any direction.
Someone mentioned my pics are too soft, yes that`s exactly my problem.
When I compare older pics made with a Wild M8 plan and a Coolpix5000 - even those seem better.
A friend mentioned that stacking software always need the same distance between the shots. I`m not sure it that`s true or not, right now I can`t measure it.
I thought I`ll add some pics to show you my system.
I`ve got the M420 with apozoom, use a Nikon D70 fixed with an adapter; use the highest JPEG setting, a SCHOTT KL1500 coldlight fibrearm, the camera is linked to a laptop, I use stacking software of Zerene.
The last pic shows a self built tool to hold the specimen. Its like a small cross table but without any possibility of measuring to any direction.
Someone mentioned my pics are too soft, yes that`s exactly my problem.
When I compare older pics made with a Wild M8 plan and a Coolpix5000 - even those seem better.
A friend mentioned that stacking software always need the same distance between the shots. I`m not sure it that`s true or not, right now I can`t measure it.
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Charles Krebs
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The first thing that I would look for are vibration problems. If I recall correctly, the D70 does not have any mirror lock-up (for shooting that is... not the one used for sensor cleaning). With a DSLR mounted directly onto a scope, on a long cantilevered stand, illuminated with fiber optics (i.e. no electronic flash) and no mirror lock-up, I can almost guarantee that you are losing image quality due to vibration introduced by the camera mirror and shutter mechanisms. How much? Hard to say, but it can be a very significant amount.
What is a typical shutter speed used for your pictures?
A Coolpix would introduce no vibration from the camera itself... so this is perhaps not that surprising.When I compare older pics made with a Wild M8 plan and a Coolpix5000 - even those seem better.
What is a typical shutter speed used for your pictures?
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Charles Krebs
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oro,
1/15 is right in the range of shutter speeds that often cause the most problems!
First you need to determine if this is actually your problem. The best way to do this is either with a very short duration electronic flash, or, trying a much longer shutter speed. I'm guessing that if you had electronic flash you would have mentioned it. So what I would try is a comparison of a long shutter speed and your "typical" (around 1/15 second) speed. Ideally you do not want to change the position of the light. If you have some neutral density you could use that to reduce the light intensity... or perhaps, for the longer exposure, pull the fiber optic light guide out an inch or two from it's socket on the illuminator. This will reduce the intensity reaching the subject greatly.
I would try to get the long exposure down to at least 4 or 5 seconds (or even somewhat longer). You want a shutter speed that is long enough that vibration will "dampen out" at the start, and then things will be motionless for most of the exposure time. This is not something you will want to do regularly, and it may result in a "noisier" picture, but it should allow you to make some comparisons to see if vibration is really a problem.
... be sure to turn off the "Long Exposure Noise Reduction" camera feature (noise reduction often makes a picture appear less sharp)
... be sure that you do not touch the table or walk or move around during the exposures.
1/15 is right in the range of shutter speeds that often cause the most problems!
First you need to determine if this is actually your problem. The best way to do this is either with a very short duration electronic flash, or, trying a much longer shutter speed. I'm guessing that if you had electronic flash you would have mentioned it. So what I would try is a comparison of a long shutter speed and your "typical" (around 1/15 second) speed. Ideally you do not want to change the position of the light. If you have some neutral density you could use that to reduce the light intensity... or perhaps, for the longer exposure, pull the fiber optic light guide out an inch or two from it's socket on the illuminator. This will reduce the intensity reaching the subject greatly.
I would try to get the long exposure down to at least 4 or 5 seconds (or even somewhat longer). You want a shutter speed that is long enough that vibration will "dampen out" at the start, and then things will be motionless for most of the exposure time. This is not something you will want to do regularly, and it may result in a "noisier" picture, but it should allow you to make some comparisons to see if vibration is really a problem.
... be sure to turn off the "Long Exposure Noise Reduction" camera feature (noise reduction often makes a picture appear less sharp)
... be sure that you do not touch the table or walk or move around during the exposures.
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rjlittlefield
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It is not true. All of the methods in all of the commonly used stacking packages will handle irregular steps with no trouble at all.oro wrote:A friend mentioned that stacking software always need the same distance between the shots. I`m not sure it that`s true or not
Of course if any step becomes so large that the in-focus regions do not overlap, then there will be a slightly OOF band in the area of no-overlap.
--Rik
That's not true, at least for Zerene Stacker. My manual stacks are not very consistent, but the software doesn't care too much. You just need to make sure the distance moved each time is smaller than the DOF.oro wrote: A friend mentioned that stacking software always need the same distance between the shots. I`m not sure it that`s true or not, right now I can`t measure it.
Although it's rather far from your camera's pop-up flash to your subject, you could try making a light pipe or snoot to get the light to the subject. They're pretty easy to make using foam board, tape, and aluminum foil.
Ok, I just made some pics, using a simple match. I just hope that my English knowledge is enough to express those specific details (I`m from Austria).
Always single shot, without any stacking, I just reduced the pic size to 640x480.
- First pic 1/40 with diaphragma completely open and coldlight as I would use for a regular mineral pic
- Second pic 1/10 with diaphragma closed about 1/3
- 3rd pic 1,6 sec, diaphragma half closed
- 4th pic 3 sec, diaphragma almost closed, only natural light no coldlight
- 5th pic 8 sed, the same
Hope I understood you correctly with this test ...
Always single shot, without any stacking, I just reduced the pic size to 640x480.
- First pic 1/40 with diaphragma completely open and coldlight as I would use for a regular mineral pic
- Second pic 1/10 with diaphragma closed about 1/3
- 3rd pic 1,6 sec, diaphragma half closed
- 4th pic 3 sec, diaphragma almost closed, only natural light no coldlight
- 5th pic 8 sed, the same
Hope I understood you correctly with this test ...
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Charles Krebs
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- Location: Issaquah, WA USA
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oro,
To do a test to check for vibration problems, it is necessary to keep the diaphragm setting exactly the same for all pictures, and keep the lighting set-up exactly the same. All you want to do is change the intensity ("level") of the light source (and as a result use different shutter speeds). Otherwise there are too many variables to judge.
To do a test to check for vibration problems, it is necessary to keep the diaphragm setting exactly the same for all pictures, and keep the lighting set-up exactly the same. All you want to do is change the intensity ("level") of the light source (and as a result use different shutter speeds). Otherwise there are too many variables to judge.
If you want the ApoZoom to perform to its best It needs to be run with the diaphragm wide open. This is true of other lenses too usually although many are reported to perform best stopped down one or two stops.
Looking at your camera adapter, I don't recognize it. I see it has a probable T mount on the top, camera end of it and a 38mm male ISO photoport fitting on the microscope side. But who made it? What is inside of it optics wise?
Looking at your camera adapter, I don't recognize it. I see it has a probable T mount on the top, camera end of it and a 38mm male ISO photoport fitting on the microscope side. But who made it? What is inside of it optics wise?
This part was made by a friend of mine. There are no other optics inside that part.g4lab wrote:
Looking at your camera adapter, I don't recognize it. I see it has a probable T mount on the top, camera end of it and a 38mm male ISO photoport fitting on the microscope side. But who made it? What is inside of it optics wise?