For what you want to do, the key is to have the subject surrounded by light, well diffused through something like paper or a ping-pong ball. I am fond of paper. A simple cylinder that fits around the subject and around the eyepiece, with light shining through it on all sides, would work well.
Well, there's an annoying typo. I had intended to type "around the subject and around the objective".
Scarodactyl wrote: would be shocked if a dino-lite could produce usable results at these mags, though I only read one of his books so far.
I share your skepticism. I also note that the reflection in the sample image looks like a conventional microscope objective: black hole surrounded by a silver ring.
If I recall correctly, Larsen used a Dino-Lite type of microscope.
I would be shocked if a dino-lite could produce usable results at these mags, though I only read one of his books so far. There is definitely epi darkfield involved, though whether within the objective or with a ring light I am not sure.
İ guess he used to coarsly observed them with Dino-Lite's and then took the photographs with microscope lenses and digital cameras by focus stacking. Dino-Lites resolution is not that high i think.
It sounds like most micrometeorite candidates collected in populated areas end up having a terrestrial origin. So we need to be careful.
In one gutter sample, Larsen found about one real micrometeorite per pound of gutter silt.
Hi Lou,
Realy mind tingling videos.
Today i bought Jan's latest book 'On the trail of Stardust' more on his methodology from Amazon as kindle downloadable.
At the end of the book he describes his capture system.
"To take extremely high-resolution color photos of micrometeorites, Jan Braly Kihle and I have constructed a special instrument, shown here, based on an Olympus EM1 Mark II camera (50MB) in combination with an all-metal telescopic tubus and ultralong working distance microscope objectives on a motorized rack allowing the camera to be moved up and down with high precision, one micron step at a time. For the highest-resolution imaging of sub-150-micron particles, a slightly modified setup is applied using an apochromatic supertelephoto lens in combination with an infinity-corrected microscope objective. The micrometeorite is mounted on a white sticky note on glass laid on a micropositioning X-Y table lighted with a specially constructed rib-cooled LED ring light. All data from the camera is captured by computer in real time. When the sequence of single exposures (the average is 150 to 200 individual pictures per micrometeorite) is completed, the stacking program assembles them into one color photo with the entire hemisphere of the stone in focus. All the color photos of micrometeorites in this book were made with this method. Developing the components, inventing the various modifications, writing the software. and constructing a rig like this has taken many years and cost a lot of money. The reward is that we can see the micrometeorites like nobody else has before, which has changed the way we think about cosmic dust particles. They are not dust, but small individual stones of amazing beauty, telling us stories about how it all began, but still guarding secrets we are eager to understand. This exciting new connection with space is now within reach for all of us. Follow the instructions in this book, and welcome to the hunt for stardust."
That's a pretty hyped up description of a regular stacking setup.
Somehow, i felt the same.
Can i ask some technical. In the first setup he described does he use a lens with the tubes he mentioned, and are the microscope lenses also infinity corrected ones.
İ understand for doing microscopy stackup best solution would be a long working distance, infinity and chromaticly corrected high quality objective such as Nikon. Infinity corrected means that the light rays coming from the subject go to the camera in parallel lines. Are these correct.
On the second setup his tele lens would be focused at infinity. (İs this correct). Why tele do you think.?
Hope not asking too many simple questions.Still trying to understand the basics. In my eyes here everyone is scientist extraordinare. So much information to process.
Yes, this is just a routine setup like we all use. Doesn't need any custom constrruction and certainly not software writing (Rik's done that for us!)
Possibly the authors were unaware of these things and had to re-invent it themselves. If so, they are very bad researchers. Since they do know the key search term, "stacking", I think this more charitable explanation doesn't fly.
I highly recommend checking out the FAQs (see tab above) on this site. They will answer all those questiions you asked, and many more that you may not have thought to ask but that would be very helpful for you to know.
Yes, this is just a routine setup like we all use. Doesn't need any custom constrruction and certainly not software writing (Rik's done that for us!)
Possibly the authors were unaware of these things and had to re-invent it themselves. If so, they are very bad researchers. Since they do know the key search term, "stacking", I think this more charitable explanation doesn't fly.
I highly recommend checking out the FAQs (see tab above) on this site. They will answer all those questiions you asked, and many more that you may not have thought to ask but that would be very helpful for you to know.
Thank you Lou,
İ will, today is my free day so begun watching thorlabs webinar. My microscope objectives so far are these.
The oil one is 100 and i guess not usable for this purpose.
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Last edited by Argu on Thu Dec 24, 2020 11:33 pm, edited 1 time in total.
I can't quite make out some of the numbers on them, but they all seem to be finite lenses designed to work with a coverslip, though the 4x and 10x will work just as well without one.
I guess you could use the oil objective if you needed to, but you would have to immerse your micrometeorite in oil too, probably reducing its scientific value.
I can't quite make out some of the numbers on them, but they all seem to be finite lenses designed to work with a coverslip, though the 4x and 10x will work just as well without one.
I guess you could use the oil objective if you needed to, but you would have to immerse your micrometeorite in oil too, probably reducing its scientific value.
Thank you a lot Lou,
Continuing to read and learn. So much to cover. ;o)
Wish you all a good night or day depending on the time zone. ;o)
I can't quite make out some of the numbers on them, but t
Hi Lou,
Sorry for that i reposted now.As i posted the picture i chosed a small size blurring the picture. I downloaded cropsize app to my iphone and now sized down the pic after sharpening it in İphone photos app.
I had some app from tiffen once that did wonderfull job in means of sharpening. Have to refind it i guess.
Quick question. As the max pic size is 102ox1020 and 300 kb, yet the site is about macrophotography and very much high resolution imaging, (also was looking to the rigs people share but mostly with low resolutions), how do you resolve (;o) ) the issue, by putting the pictures offline and giving links or by sharpening before ?
Hope this is a valid question. ;o)
Actually that is a valid question that many of us have had. I think it is a matter of storage space for the forum. Hosting big images off-site is a common solution here. But if you look through the forum, you can see that there are many examples of crystal-sharp images, showing that the size limits are not excessive. It is often necessary to see an image to 100% to check sharpness, but we do that by cropping a little piece of the image and expanding that to maximum allowed size. We typically do that for a crop from the center, edge, and corner. This tells us most of what we need to know about the comparative sharpness of whatever we are testing or demonstrating.
I can now read your objective numbers perfectly, by the way. I see that contrary to what I thought before, your 4x is not designed for a cover slip, but as I said above, for the 4x and 10x it does not matter whether you use a coverslip or not. The sensitivity to the presence or absence of a coverslip depends on the NA of the objective. There is no strict dividing line but generally an objective with an NA of less than 0.25-0.30 will not be sensitive to the presence or absence of the coverslip, and objectives with NA greater than 0.4 should be used as designed, with the coverslip thickness that is written on the objective, in your case 0.17 which is a common standard size.
Thank you Lou for your kind answers, i will learn image issues better, working on it.
The site with the quality of you members and the topics depth and variety realy thrills me, very happy for that.
Have a micro stepper motor operated mini slider design in mind and already 3d printed a prototype part but have issues with my printer now and the screws i intend to use as rails maybe too thin. Maybe parallel to this project i will go and acquire real macro rails and a 25 mm micrometer to put together a manuel one.
Many thanks again.
