minimizing harm

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mintakax
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minimizing harm

#1 Post by mintakax » Mon Jul 29, 2019 12:21 am

Hello-- I have become fascinated with micro biology. My son lent me his Omax microscope and I immediatly examined a sample of water from the bed of an outdoor fountain. There were many Stentors and a few other organisms. After observing these for an afternoon, I became disturbed at the possible harm I was causing them. I am a devout Buddhist and harming other beings for recreational purposes does not sit well with me personally. I am not judging anyone else here at all. I realize that this is a bit of an extreme reaction and that breathing, walking around, etc damages more micro organisms than sampling some water for observation. Nonetheless, I see these creatures as other beings and if I am going to continue with this I want to make sure that I minimize the harm. I am using slides that have indents, rinsing and returning samples to where I obtained them and using an LED illumination source. Any other advice or comments regarding this ?

Thanks,
Dan

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Re: minimizing harm

#2 Post by PeteM » Mon Jul 29, 2019 2:05 am

Thin petrographic samples under polarized light are pretty cool.

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Re: minimizing harm

#3 Post by apochronaut » Mon Jul 29, 2019 2:45 am

A considerable number of the organisms one views in water samples from the wild , most if not all in fact, have evolved strategies of survival that include very clever defenses to deal with the normal conditions associated with their existence in the environment.

As long as the conditions of viewing of them does not depart too severely from conditions they might normally encounter in their environment, they can and will survive.

Using well slides and then returning the sample as you do, is helpful to them. If the sample does dry, there would be a natural tendency by many organisms to encyst , a condition from which they can return to an active stage, if the slide is soaked in the same or similar water from which they came.

Although led lighting is cool, many such sources release high levels of uv light. UV light in high concentration is a microbe sterilant and in fact is used industrially as such. Perhaps a better idea would be to buy an older microscope with a mirror and a remote illumination source which produces a yellowish light closer in quality to daylight. Such sources of illumination are cool......or better still; do as many naturalists have done. Confine your observations to daytime and use the sky as a light source. Microscopes of this type equipped with good lenses, produce images that are just as good and potentially superior to those produced by a modern budget scope like an Omax.

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Re: minimizing harm

#4 Post by 75RR » Mon Jul 29, 2019 4:07 am

I am using slides that have indents, rinsing and returning samples to where I obtained them
That is the most that one can really do, and already involves a fair bit of effort and thoughtfulness.

In general only dedicated UV LED lights have sufficient UV to worry about. LEDs that come factory installed in microscopes are fine.

If however you are going to DIY LED illumination with an unidentified LED bulb that is another matter.
Last edited by 75RR on Mon Jul 29, 2019 10:05 am, edited 1 time in total.
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Re: minimizing harm

#5 Post by MicroBob » Mon Jul 29, 2019 4:32 am

Hi Dan,
it is always a good idea to think about minimizing the negative impact of one's activities on the environment.
One way to treat pond samples is to take a glass of pond water and some plants, perhaps stones and sand, and to install a small pond aquarium where samples are released back in quickly after examination.
In my view the biggest danger to placton samples is to be washed away in the kitchen basin instead of being released back into a pond, so this might help.
I have installed a 30 liter plancton aquarium into which I release my fres water samples.

I wouldn't worry about the LED, it is a quite good compromise. Bulbs emit a lot or IR light which would be harmful and sunlight also contains UV light.
The LEDs that are intended for microscope and lighting use emit very small levels of UV, see page 11:https://www.ebay.de/itm/Cree-XLamp-XHP5 ... 2749.l2649

Bob

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Re: minimizing harm

#6 Post by mintakax » Mon Jul 29, 2019 6:27 am

Thanks everyone for your comments ! I really like the idea of an aquarium and I'm going to do something like that.
So, moving forward.... What would be the best system for me ? I do want to take as high quality videos as possible. I have a lot of experience with Macro, wildlife and underwater videography/photography. My current camera is a Nikon Z6 full frame mirrorless . I also have a couple of decades experience with astrophotography (don't do it anymore). I am however a rank beginner in microscopy but am really intrigued with the various illumination systems, dark field, DIC and phase contrast.

I'd like to have a system that I could grow into, my budget is $3K give or take. From reading this forum I see that the best equipment is used and I'm good with that. I'd like to purchase as complete a system as possible, but do want to make sure that it is LED illumination so I don't over heat any creatures. Any recommendations to start ? I'm a fast learner.

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Re: minimizing harm

#7 Post by 75RR » Mon Jul 29, 2019 6:50 am

I'd like to purchase as complete a system as possible, but do want to make sure that it is LED illumination so I don't over heat any creatures. Any recommendations to start ?
Nothing wrong with LED illumination if you want it, but if the reason is solely to mitigate heat then you should know that it is not a problem if you have an external lamp house - that was what they were designed for.

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Re: minimizing harm

#8 Post by MichaelG. » Mon Jul 29, 2019 7:09 am

Welcome, Dan

Along with those who already commented; I have great respect for your position on this ... You will, I am sure derive much more pleasure from your observations if you feel comfortable that you are causing no avoidable harm.

As mentioned, there are wonderful inanimate things that you could study; but, as you have already found, the animal kingdom has special appeal [perhaps because we all feel some 'connection' with these creatures, despite not expressing it in the pure form that you do].

To me: Your general protocol seems very appropriate ... You are observing living creatures in a way that is unlikely to cause them harm, and then returning them home.

In addition to the cavity slides, you might consider some of the devices that previous microscopists invented, to produce a micro-aquarium on a slide.

Thank you for sharing your feelings on this predicament ... it does us all good to pause for thought.

MichaelG.

.

P.S. The system has just notified me that other posts have been made whilst I was composing my thoughts ... but I am posting this as it stands; in the hope that it is not redundant.

.
Edit: You may find inspiration for an acceptable micro-aquarium design, here:
http://www.microscope-antiques.com/liveboxes.html
Too many 'projects'

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Re: minimizing harm

#9 Post by mintakax » Mon Jul 29, 2019 2:26 pm

Thanks MichaelG-- any modern day variations of live boxes ? I love the idea.

Also thanks 75RR- I would be interested in a system like that with an external lamp box or LED. I'd like to buy used. The astronomy hobby has a forum named "astromart" where folks buy, sell and trade their equipment. Does such a place exist for microscopy ? If not, are there recommended dealers for use equipment ? I know Ebay has much but wondering if a dealer might be better for someone inexperienced ?

I'd love any recommendations for a system.


When I realized that I could go out to my fountain, put a small piece of detritus on the indented slide, see lots of these creatures and put my phone camera up to the eyepiece, I thought I'd like to continue with this .

https://vimeo.com/350745029

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Re: minimizing harm

#10 Post by Sauerkraut » Mon Jul 29, 2019 2:48 pm

apochronaut wrote: Although led lighting is cool, many such sources release high levels of uv light. UV light in high concentration is a microbe sterilant and in fact is used industrially as such.
Well this is interesting. I too am on the 'catch and release' program for pond microbes and hadn't considered harm from UV rays. Would a UV camera filter placed over the light source help minimize the harmful effects?

Also, hang tightly on to your slides when washing them off in the pond. Lost a deep well slide the other day after it slipped out of my hands. You would think I could locate it but no. It's gone.

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Re: minimizing harm

#11 Post by MichaelG. » Mon Jul 29, 2019 3:27 pm

mintakax wrote:Thanks MichaelG-- any modern day variations of live boxes ? I love the idea
On the same site, you will find a page about Compessoria
http://www.microscope-antiques.com/compressors.html
These are intended for gently holding somewhat larger creatures in position, for examination.
Obviously, there is some 'engineering' overlap with the live box idea.

The most modern one illustrated, is the subject of this Patent:
https://worldwide.espacenet.com/publica ... cale=en_EP
... which you can download as a PDF

Hopefully that will set you thinking about what general design would suit your needs.
... I would be very happy to exchange ideas about this, either on the forum or by personal message.

MichaelG.
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Re: minimizing harm

#12 Post by apochronaut » Mon Jul 29, 2019 4:04 pm

The jury is definitely out on both the environmental benefits of leds and whether they are harmful to the eyes under excessive or prolonged use.
OK, they use less energy but due to homo sapiens' penchant for parasitic behaviour, we find ever more ways to waste the energy nevertheless, releasing ever more C02 into the atmosphere, with 80" T.V. screens and football sized urban billboards, not to mention absolute inane shit like facebook and crypto currency mining. If anyone is deluding themselves that using an led microscope bulb, is saving the environment????

Are leds o.k. for the eyes? Maybe for someone who has already a degree of eye failure and isn't going to be around in another 12 years, it might not matter that much but a disproportionate number of minimally engineered led illuminated scopes are going to be used by children, and some of them, the real keeners will be staring into their glow for hours on end, for days on end.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5313540/
https://opto.ca/health-library/blue-lig ... sk-of-harm

While it could be argued and is often so, that the uv levels are low, there are research papers out there that show that deep blue and especially the lack of red and near IR are also deleterious to the eyes. It is apparently as much a case of the balance in wavelengths , as it is the actual wavelengths themselves.

Regarding the affect of uv and or monochromatic light on micro-organisms. Around 1994, when the buzz about CFC's and the ozone layer was pretty big I made up a simple experiment. It has it's flaws but the results were real and real interesting.
I took 5 identical boxes, 4 with lids and 1 with the lid removed. I separated a scummy pond water sample into 5 equal parts, with a similar amount of scum and put each part in a covered petri dish. I took a sample from each dish and examined it in BF, noting as many organisms as possible. I got about 20, some I knew, like a type of spirogyra, there was a small amoeba, various ciliates. I noted them as accurately as I could and for the others, I made some drawings with descriptions.
Each box received one of the petri dishes in the bottom and the 4 boxes with lids, received a 6" fluorescent tube fixture either on the lid, or suspended slightly below. I attempted to adjust the intensity of the light in each box by lowering some of the fixtures. Each fixture, received a different tube; cool white, daylight, a detector lamp and a blue blacklight( with wood's glass). The open box received daylight filtered through glass.

The dishes were examined microscopically at specific intervals but very early on, something was happening with those from the 3 boxes containing the higher levels of blue and uv light. After 3 weeks there was a marked disturbance caused by the light from all 4 artificial sources, with the emergence of dominant previously undetected species or forms under the cool white, daylight and detector illumination. A couple of these became dominant as odd forms of algae, with red pigmentation rather than chlorophyll. There was a great deal of mortality, progressively with the increase in colour temperature, with almost complete mortality occurring under the blue blacklight. There were some extant organisms under the blue blacklight and curiously some overgrowth of the red algae form but it was a pretty dead environment after 3 weeks. The box receiving only glass filtered daylight , changed only a little, with some reduction in the chlorophyll containing components. Each petri dish was fed with several grains of brown sugar once a week. Not sure what this says but it was eye opening to me, at the time.

https://www.whoi.edu/website/redtide/re ... nt-trends/

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Re: minimizing harm

#13 Post by 75RR » Mon Jul 29, 2019 5:21 pm

I would be interested in a system like that with an external lamp box or LED. I'd like to buy used. The astronomy hobby has a forum named "astromart" where folks buy, sell and trade their equipment. Does such a place exist for microscopy ? If not, are there recommended dealers for use equipment ? I know Ebay has much but wondering if a dealer might be better for someone inexperienced ?
There are not as many microscopists as there are astronomers so you will most likely find less outlets.

Have a look in this forum in the For forum members who want to buy and sell equipment section. Post a request for equipment.

Similarly you can have a look in https://www.photomacrography.net/forum/ ... d834bb6a73

Location is also important, what with shipping and import taxes. Where are you located?

Brunel Microscopes in the UK has a used section: http://www.usedmicroscopes.co.uk/
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Re: minimizing harm

#14 Post by Hobbyst46 » Mon Jul 29, 2019 5:43 pm

My recent hours with an Olympus BH2 illuminated by an externally fixed 100W halogen lamp, fully support 75RR's experience that heat from such lamp is not necessarily an issue.

My thought about the negligible contribution of LEDs to the environment is the same as Apochronaut's. Global population growth and demand for instrumentation annihilates all benefits of energy savings.

I also second Apochronaut's opinion, that excessive blue and violet and near UV wavelength light, should be avoided, since their maleffect on human health is not fully known.

Yet, the unknown IMO is - do current high power LEDs emit too much short wavelength light. They definitely emit (relatively) more than halogen. I still think that visible light LEDs do not emit UV.
So the balanced approach, IMO, is to use LEDs where they offer brightness which is unachievable with externally mounted halogen illuminators, BUT filter out much of the short wavelength light. That is, cutoff much of the light below 450nm.
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Re: minimizing harm

#15 Post by Sauerkraut » Mon Jul 29, 2019 6:00 pm

So based on this thread, it could possibly help long-term eye health by putting a UV filter over a halogen light source?

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Re: minimizing harm

#16 Post by MicroBob » Mon Jul 29, 2019 6:40 pm

Sauerkraut wrote:So based on this thread, it could possibly help long-term eye health by putting a UV filter over a halogen light source?
Here is an interesting articel about halogen lamp filtering (in english! :D ): https://www.fh-muenster.de/ciw/download ... ish_-1.pdf

I think halogen lamps are always used with a filter against UV radiation. This should be taken into account when building/repairing microscopes.
IR light is not harmless too: It is transmitted by glass lenses and the eye doesn't detect too much of IR light to protect itself. As far as I know this is one of the reasons for the blue filter in the light path of many microscopes.

Bob

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Re: minimizing harm

#17 Post by MichaelG. » Mon Jul 29, 2019 9:37 pm

MicroBob wrote:IR light is not harmless too: It is transmitted by glass lenses and the eye doesn't detect too much of IR light to protect itself. As far as I know this is one of the reasons for the blue filter in the light path of many microscopes.
I'm happy to be proved wrong, Bob ... but my understanding is that the usual blue filter is an 82B, which adds 300Kelvin, which was enough to shift the colour temperature of a low voltage lamp to suit Tungsten-balanced photographic film.
If you have a high power lamp [such as in a slide projector] there should also be a dedicated IR blocking filter [which is visually clear] in the light path, to protect the slide and the projection lens.

MichaelG.

.
Edit: Jeremy Sanderson's recent book includes a useful chart, on p740 ... which, fortuitously, is included in the 'Google Books' extract:
https://books.google.co.uk/books?id=9uO ... J&pg=PA740
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Re: minimizing harm

#18 Post by actinophrys » Mon Jul 29, 2019 10:56 pm

mintakax wrote:Nonetheless, I see these creatures as other beings and if I am going to continue with this I want to make sure that I minimize the harm. I am using slides that have indents, rinsing and returning samples to where I obtained them and using an LED illumination source. Any other advice or comments regarding this ?
I think this is an admirable sentiment. The main thing is probably to pay attention to your sample. I use a microscope with a lamp, and it seems like you can keep most protozoans and small animals on the slide for a good while without apparent harm, so long as you watch out for when the water starts evaporating. But blue Stentor and red Blepharisma are photosensitive, and in marshes many twisted ciliates like Caenomorpha are hurt by oxygen, so things like those probably shouldn't be kept too long without shelter. And note if you have many ciliates stuck in the same drop as suctorians, more will get eaten.

My experience with water samples is that most will keep 2-3 days before the flora and fauna start shifting. You can decide whether that counts as harm or natural succession. But be cautious with samples from cold running water; those lose oxygen as they warm up, and after a while things like small crustaceans and worms can suffocate. You would want to try to keep them aerated and cool, and return them relatively soon to avoid damage. I think water from puddles is probably the safest to keep for a while, though of course each habitat will give you different things. Best of luck!

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Re: minimizing harm

#19 Post by PeteM » Tue Jul 30, 2019 2:09 am

mintakax wrote:... What would be the best system for me ? . . .
Given a $3K budget and the hope to explore a wide range of imaging techniques, some suggestions:

- An Olympus BHS microscope, about $1K to start and gradually acquiring special illumination methods and objectives as you learn. The BHS has enough illumination to handle most any method and with a lamphouse well to the back. It's also an easy LED conversion.

- A Nikon Optiphot. Very similar to the Olympus in most respects.

- Possibly a high quality inverted microscope for pond critters.

By going to this generation of microscope (BHS/Optiphot) you'll find a wide range of top quality accessories available, lots of online assistance, and availability of things like high quality objectives, phase contrast and darkfield condensers, maybe even Hoffman modulation contrast under $3K.

When you have enough posts to send a message, I can also send you an overview of microscope brands and models we use in our "Micronaut" kids and parents program. It covers pros and cons and some things to look for in over a hundred models of microscopes. There are at least a couple dozen other superb microscopes available and worth considering if you happen to stumble across one fairly complete and at a good price.

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Re: minimizing harm

#20 Post by mintakax » Tue Jul 30, 2019 4:10 am

Thanks PeteM--

I really like your idea of the Olympus BHS. I've spent the last hour hunting these down and I'm wondering does BHS mean BH Series ? I see BH2, BH2/BHS, some loaded with accessories and some seem to not have the external light housing. Is there one standard BH2/BHS ?

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Re: minimizing harm

#21 Post by 75RR » Tue Jul 30, 2019 4:15 am

I really like your idea of the Olympus BHS. I've spent the last hour hunting these down and I'm wondering does BHS mean BH Series ? I see BH2, BH2/BHS, some loaded with accessories and some seem to not have the external light housing. Is there one standard BH2/BHS ?
The repair support instructions for this microscope are a gold mine.

http://www.alanwood.net/photography/oly ... loads.html
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Re: minimizing harm

#22 Post by PeteM » Tue Jul 30, 2019 4:24 am

mintakax wrote: . . .. Is there one standard BH2/BHS ?
The BH-2 is a series name (following the BH microscopes from Olympus). At the time, this series had the highest market share among professionals. It was a very good scope, lots sold, and all sorts of system accessories. That also means a robust used market still today. Within that series there are various models. Some of the differences include lamp intensity and the presence (or absence) of a removable nosepiece. The brighter lamp is useful for methods such as phase contrast, darkfield, and DIC (especially at high magnification). The standard lamp will do OK for most viewing.

BHS: bright lamp, removable nosepiece, massive stand adds a bit of stability, best of the scopes but more expensive used.

BHT: standard lamp, removable nosepiece (which you may want for different methods/objectives). If you're going to do a LED replacement (not necessary IMO, but could add a bit of brightness), might as well get this one. You could, for example, have one nosepiece with regular DPlan objectives for casual viewing, another with SPlan or SPlan Apo objectives for critical photo work, and still another with phase contrast objectives. Takes just a few seconds to swap them out.

BHTU: standard lamp, fixed nosepiece with the objectives facing away from the user. With the objectives facing backward, it's faster to swap slides in and out for someone doing clinical diagnosis.

BHM: metallurgical version, reflected illumination.

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Re: minimizing harm

#23 Post by mintakax » Tue Jul 30, 2019 5:14 am

75RR wrote:
I really like your idea of the Olympus BHS. I've spent the last hour hunting these down and I'm wondering does BHS mean BH Series ? I see BH2, BH2/BHS, some loaded with accessories and some seem to not have the external light housing. Is there one standard BH2/BHS ?
The repair support instructions for this microscope are a gold mine.

http://www.alanwood.net/photography/oly ... loads.html
Yes, I've seen those and I hope to be an owner soon !

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Re: minimizing harm

#24 Post by mintakax » Tue Jul 30, 2019 5:15 am

PeteM wrote:
mintakax wrote: . . .. Is there one standard BH2/BHS ?
The BH-2 is a series name (following the BH microscopes from Olympus). At the time, this series had the highest market share among professionals. It was a very good scope, lots sold, and all sorts of system accessories. That also means a robust used market still today. Within that series there are various models. Some of the differences include lamp intensity and the presence (or absence) of a removable nosepiece. The brighter lamp is useful for methods such as phase contrast, darkfield, and DIC (especially at high magnification). The standard lamp will do OK for most viewing.

BHS: bright lamp, removable nosepiece, massive stand adds a bit of stability, best of the scopes but more expensive used.

BHT: standard lamp, removable nosepiece (which you may want for different methods/objectives). If you're going to do a LED replacement (not necessary IMO, but could add a bit of brightness), might as well get this one. You could, for example, have one nosepiece with regular DPlan objectives for casual viewing, another with SPlan or SPlan Apo objectives for critical photo work, and still another with phase contrast objectives. Takes just a few seconds to swap them out.

BHTU: standard lamp, fixed nosepiece with the objectives facing away from the user. With the objectives facing backward, it's faster to swap slides in and out for someone doing clinical diagnosis.

BHM: metallurgical version, reflected illumination.
Thanks Pete!

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Re: minimizing harm

#25 Post by mintakax » Tue Jul 30, 2019 2:26 pm

When I started my search for a used system, I initially thought it would be way easier than purchasing astronomy equipment (which I have done for decades). In fact, the opposite is true. I am really surprised at the complexity ,variety and sophistication that describes microscopy equipment.

I have located a couple of Olympus BH2/BHS and Nikon Optiphot 2 scopes but before I buy I would really appreciate anyones thoughts on whether I might be better served with an inverted microscope ? There seems to be a lot of these on the used market. For examination and video recording (important to me) of pond and water organisms, how would an inverted scope compare ? It seems I would be looking through the bottom of dish rather than a slide ? Would there be more issues with creatures traveling in and out of focus ? They also seem to be limited to 40x objectives, but 40x has seemed sufficient so far for me. I know the inverted scopes are larger, but I have a dedicated table. How about from the standpoint of returning creatures unharmed ?

I very much appreciate all the help and advice that I have received so far !

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Re: minimizing harm

#26 Post by Hobbyst46 » Tue Jul 30, 2019 2:38 pm

Simple inverted microscope only have coarse focus. So they are only useful for low magnifications. Better inverted scopes have a fine focus as well and are useful up to highest mag, including immersion and all illumination and contrast modalities. They are very popular for live cell research.

BTW, one advantage of the BH2 over some other scope makes is the availability of excellent documentation by Alan Wood and Carl Hunsinger.
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Re: minimizing harm

#27 Post by Sauerkraut » Tue Jul 30, 2019 2:43 pm

Thank you for the information on upgrading scopes, PeteM. I had been wondering the same thing.

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Re: minimizing harm

#28 Post by Wes » Tue Jul 30, 2019 4:15 pm

MicroBob wrote: IR light is not harmless too: It is transmitted by glass lenses and the eye doesn't detect too much of IR light to protect itself. As far as I know this is one of the reasons for the blue filter in the light path of many microscopes.
I always thought the blue filter is to correct the color temperature for photography and slightly improved resolution. I recently added a KG-1 protective filter that effectively blocks IR. My goal was to prevent damage of the optical elements at the rear focal plane of the objective where temperature could rise drastically due to focusing of IR light.

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Re: minimizing harm

#29 Post by Hobbyst46 » Tue Jul 30, 2019 4:22 pm

Wes wrote:
MicroBob wrote: IR light is not harmless too: It is transmitted by glass lenses and the eye doesn't detect too much of IR light to protect itself. As far as I know this is one of the reasons for the blue filter in the light path of many microscopes.
I recently added a KG-1 protective filter that effectively blocks IR. My goal was to prevent damage of the optical elements at the rear focal plane of the objective where temperature could rise drastically due to focusing of IR light.
Good idea. I used KG5 to block the heat from 100W Hg and 75W Xe lamps.
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Re: minimizing harm

#30 Post by 75RR » Tue Jul 30, 2019 5:16 pm

I have located a couple of Olympus BH2/BHS and Nikon Optiphot 2 scopes but before I buy I would really appreciate anyones thoughts on whether I might be better served with an inverted microscope ? There seems to be a lot of these on the used market. For examination and video recording (important to me) of pond and water organisms, how would an inverted scope compare ? It seems I would be looking through the bottom of dish rather than a slide ? Would there be more issues with creatures traveling in and out of focus ? They also seem to be limited to 40x objectives, but 40x has seemed sufficient so far for me. I know the inverted scopes are larger, but I have a dedicated table. How about from the standpoint of returning creatures unharmed ?

Have a look at this thread: viewtopic.php?f=5&t=7384&p=65044
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