If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Micro / Macro question?
I need to photograph small objects at a distance of 2-4 inches (5-10 cm) from
the lens. I want a magnification of ~50 to 100. Photomicrography (using microscopes) is limited in the working distance from the objective; it needs to be 1 inch. Photomacrography is limited in the magnification; typically 10. I'd like a solution that terminates with filter threads (any size can be adapted) so I may attach a digicam. Suggestions? If there is a better forum in which to ask this question, just point the way... Thanks. -- Dr. Leonard. H. McCoy "I'm a *doctor*, Jim, not a *magician*!" |
#2
|
|||
|
|||
Micro / Macro question?
Hi Doc,
Seems like your solution would be an 'industrial' type microscope, not the ones used in medicine. These usually go to the magnification and the working distances you need. The better ones will zoom and have a ring-type illuminator. A camera will usually attach with a 'C' mount. If you want to use a P&S camera, make sure that a 'C' mount can be attached to it. A stereo microscope with a camera tube will let you view the image through the right lens, while using the left one for the camera. Fancier ones will even have a third objective lens, allowing taking photographs while having full stereo vision. Hope this helps. "Dr. Leonard H. McCoy" wrote in message obal.net... I need to photograph small objects at a distance of 2-4 inches (5-10 cm) from the lens. I want a magnification of ~50 to 100. Photomicrography (using microscopes) is limited in the working distance from the objective; it needs to be 1 inch. Photomacrography is limited in the magnification; typically 10. |
#3
|
|||
|
|||
Micro / Macro question?
What is the size of the object to be photographed?
~50 micron Is it two dimensional? 3D Is it important to keep the entire depth in focus? No. How much depth is there? They are roughly spherical in shape. Is the surface shiny or flat? Not sure. Not important. Suspended, submerged in clear water, so of high contrast. Is there a lot of detail? No. Confirming presence and number will be sufficient. Does the subject move? No. What type of camera are you using or do you have available? Have Canon P&S A95 digital. How will the results be viewed? Digital photos to be e-mailed to other researchers. -- Dr. Leonard. H. McCoy "I'm a *doctor*, Jim, not a *magician*!" |
#4
|
|||
|
|||
Micro / Macro question?
Dr. Leonard H. McCoy wrote:
What is the size of the object to be photographed? ~50 micron 1 millimeter = 1,000 microns so if they were closely spaced, 100 of them could be counted in a screen sized mm wide strip (ballpark scope). Confirming presence and number will be sufficient. What type of camera are you using or do you have available? Have Canon P&S A95 digital. 7.18 x 5.32 mm sensor so the 1mm wide frame would be about 7x.... but that's not how things are stated in photography, the "7x" in camera speak is a completely different number, anyways it would be a job for a microscope mounted camera. The Nikon Multiphot system http://www.microscopyu.com/museum/multiphot.html .... goes up to 40x which means a 24x36mm sensor capturing 40x life size. 1/40th of 36mm is .9mm... round that off to 1mm so that would work for your purposes with a DSLR, but you don't need to make huge beautiful prints at that size so probably something much less powerful is needed. How will the results be viewed? Digital photos to be e-mailed to other researchers. Re-reading your original question.... I need to photograph small objects at a distance of 2-4 inches (5-10 cm) from the lens. I want a magnification of ~50 to 100. Photomicrography (using microscopes) is limited in the working distance from the objective; it needs to be 1 inch. Hmmm, so you need a longer focal length to keep further from the subject. That is odd because extreme closeups are usually done with short focal length lenses, like the Multiphot above uses 19mm at 1:40 and 120mm at 1:1. To use longer focal lengths would require a very long tall bellows. Photomacrography is limited in the magnification; typically 10. I'd like a solution that terminates with filter threads (any size can be adapted) so I may attach a digicam. Suggestions? If there is a better forum in which to ask this question, just point the way... |
#5
|
|||
|
|||
Micro / Macro question?
Hmmm, so you need a longer focal length to keep further from the
subject. That is odd because extreme closeups are usually done with short focal length lenses, like the Multiphot above uses 19mm at 1:40 and 120mm at 1:1. But since the subjects are submerged, longer working distance is necessary. To use longer focal lengths would require a very long tall bellows. For example...? Can you give me an idea of what lens (backward?) and what bellow length? Just a ball park idea... -- Dr. Leonard. H. McCoy "I'm a *doctor*, Jim, not a *magician*!" |
#6
|
|||
|
|||
Micro / Macro question?
"Joseph Meehan" wrote:
In the traditional sense Macro is anything recorded on the light sensitive material at life size or smaller to about half to quarter life size. Micro is used for anything recorded larger than life size. Those terms don't have a lot of meaning in the digital world with the changes in sensor size, but from a technical view, I would guess they still apply. From "The Science of Imaging: An Introduction" by Graham Saxby, Photomacrography is the making of an image that is larger than the object using conventional camera technques. Photomicrography is te technique of imaging through a microscope. Generally though, macro has become more broad in meaning and is now commonly used for 1:4 ratios on zoom lenses rather than only at 1:1 or more. But the basic difference is the use of a compound microscope (micro) rather than a generic camera lense (macro). -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#7
|
|||
|
|||
Micro / Macro question?
Dr. Leonard H. McCoy wrote:
Hmmm, so you need a longer focal length to keep further from the subject. That is odd because extreme closeups are usually done with short focal length lenses, like the Multiphot above uses 19mm at 1:40 and 120mm at 1:1. But since the subjects are submerged, longer working distance is necessary. You want to look at a web cam mounted on a dissecting scope. That combination will give you the lense to subject distance you need and allow both optical and through the camera viewing (and you will soon enough determine that optical viewing is great for the initial setup, while through the camera viewing is essential for photography). This web site has a large selection of articles describing virtually all aspects of photomicrography. For you purposes be sure to read the ones involving dissecting microscopes, but for a general overview you'll want at least scan through some of the others too. http://www.microscopy-uk.org.uk/mag/libindex3.html To use longer focal lengths would require a very long tall bellows. For example...? Can you give me an idea of what lens (backward?) and what bellow length? Just a ball park idea... To get the magnification you need, that is not within reason. -- Floyd L. Davidson http://www.apaflo.com/floyd_davidson Ukpeagvik (Barrow, Alaska) |
#8
|
|||
|
|||
Micro / Macro question?
http://www.microscopy-uk.org.uk/mag/libindex3.html
Thank you. -- Dr. Leonard. H. McCoy "I'm a *doctor*, Jim, not a *magician*!" |
#9
|
|||
|
|||
Micro / Macro question?
Dr. Leonard H. McCoy wrote:
Hmmm, so you need a longer focal length to keep further from the subject. That is odd because extreme closeups are usually done with short focal length lenses, like the Multiphot above uses 19mm at 1:40 and 120mm at 1:1. But since the subjects are submerged, longer working distance is necessary. To use longer focal lengths would require a very long tall bellows. For example...? Can you give me an idea of what lens (backward?) and what bellow length? Just a ball park idea... I think it's a microscope job but I'll try to make an educated guess for an SLR setup. A regular 200mm lens needs about 200mm of extension/bellows to reach 1:1 and a typical bellows is about 200mm, so, I'm not sure, say you start with a 200mm macro lens already at 1:1, another 200mm of extension brings it to 1:2 which is still a 12mm wide field of view and you want to see about a 1mm frame. Well, if that's a 10MP image, 3,000 pixels across & 3 pixels is enough to resolve an object & you can crop to 750 pixels wide field of view of 3mm... not rteally enough detail. I'm not sure the working distance of this setup but would guess at least 4 inches. The Canon 65mm MPE goes to 1:5 and probably has a working distance considerably less than 2 inches so maybe an in between focal length, 100mm macro lenses are common but I think you'd need something designed for more magnification: something more like a microscope lens, not a 35mm still lens: Here's that Multiphot setup with what looks to be about 400mm of extension (twice the size of a normal bellows): http://www.naturfotograf.com/images/U020812490.jpg Here's the lenses which go with it: http://www.naturfotograf.com/lens_spec.html |
#10
|
|||
|
|||
Micro / Macro question?
Hi there,
"Dr. Leonard H. McCoy" wrote in message obal.net... I need to photograph small objects at a distance of 2-4 inches (5-10 cm) from the lens. I want a magnification of ~50 to 100. If it can be done, then the people at Brunel Microscopes will know: http://www.brunelmicroscopes.co.uk/ I have several of their IMXZ 'scopes with digital cameras for field of views ranging from 50mm diameter down to around 1mm. At 1mm you will easily be able to count/detect 50um particles. A |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Micro / Macro question? | Dr. Leonard H. McCoy | Digital Photography | 14 | April 2nd 08 01:55 PM |
Micro Macro | ~~NoMad~~ | Digital Photography | 3 | July 17th 07 05:42 PM |
Macro/Micro for Nikon | Sheldon | Digital SLR Cameras | 15 | July 5th 06 03:10 AM |
Macro/micro Again! | JackN | Digital Photography | 11 | May 4th 05 11:11 AM |
Micro/Macro Photography | TravisMLC | Digital Photography | 5 | July 3rd 04 09:37 PM |