LED Illumination Comparison
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LED Illumination Comparison
As I just upgraded my Amscope T680A to LED, I thought I'd post a quick comparison with the factory fitted T720 LED and with daylight. All images taken at 10x and using the little Toupcam 5MP USB2 EP camera. Also with Sharpcap v4 capture software. The Toupcam was connected to the T720 via an eyepiece tube and to the T680 via the trinocular tube. I just used a small mirror to catch the overcast daylight from the East. All specimens were (Chinese) prepared slides - not the best, but still. All reduced to 30% of original size.
Spirogyra
T720 LED:
T680 LED (Adjusted hue -> green:)
T680 Day:
Will attach some more in a second post
Louise
Spirogyra
T720 LED:
T680 LED (Adjusted hue -> green:)
T680 Day:
Will attach some more in a second post
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
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Re: LED Illumination Comparison
Human skin
T680 LED
T680 Day
T720 LED
T680 LED
T680 Day
T720 LED
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
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Re: LED Illumination Comparison
Maize
T680 LED
T680 Day
T720 LED
T680 LED
T680 Day
T720 LED
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
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Re: LED Illumination Comparison
From the above, you can see that unfiltered daylight is always bluer than either LED. It's not clear how much the camera itself plays a part in the colour rendition but not an issue for comparison purposes. The Sharpcap capture software (for astronomy really...) allows quite a bit of colour adjustment ahead of capturing single files though I think I only adjusted the hue for the T680 LED Spirogyra. The option is there to adjust the colour/brightness/contrast as well as exposure, gain, white balance, gamma in Sharpcap.
Louise
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
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Re: LED Illumination Comparison
What do you mean by daylight?
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Re: LED Illumination Comparison
A cloudy sky
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
Re: LED Illumination Comparison
A surprising amount of blue.LouiseScot wrote: ↑Tue May 24, 2022 5:50 pmFrom the above, you can see that unfiltered daylight is always bluer than either LED. It's not clear how much the camera itself plays a part in the colour rendition
As an astronomer you do know that all such astro equipment comes with free clouds
So, , , a use for those clouds at last !!! What do you get when you point your camera + 'scope at the free clouds ?
I would expect white (aka northlight)
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Re: LED Illumination Comparison
I would expect 'white' but at a higher colour temperature than the LED and which would be variable. I suppose one advantage of an LED is that the colour temperature is fixed for a particular device. But that colour temperature will be determined by the stimulating/blue wavelength and the stimulated wavelengths determined by the emitting phosphors, I think. If I was of a mind to I could dig out my slit spectrometer, get it up and running again, and point it at some LEDs...SWmicro wrote: ↑Tue May 24, 2022 6:17 pmA surprising amount of blue.LouiseScot wrote: ↑Tue May 24, 2022 5:50 pmFrom the above, you can see that unfiltered daylight is always bluer than either LED. It's not clear how much the camera itself plays a part in the colour rendition
As an astronomer you do know that all such astro equipment comes with free clouds
So, , , a use for those clouds at last !!! What do you get when you point your camera + 'scope at the free clouds ?
I would expect white (aka northlight)
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
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Re: LED Illumination Comparison
How did you get the light to the slide.
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Re: LED Illumination Comparison
Via a small mirror - I did explain at the start of the thread...apochronaut wrote: ↑Tue May 24, 2022 6:48 pmHow did you get the light to the slide.
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
Re: LED Illumination Comparison
I'd be interested in seeing that thread.LouiseScot wrote: ↑Tue May 24, 2022 6:28 pmI would expect 'white' but at a higher colour temperature than the LED and which would be variable. I suppose one advantage of an LED is that the colour temperature is fixed for a particular device. But that colour temperature will be determined by the stimulating/blue wavelength and the stimulated wavelengths determined by the emitting phosphors, I think. If I was of a mind to I could dig out my slit spectrometer, get it up and running again, and point it at some LEDs...
Louise
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Re: LED Illumination Comparison
You mean the output of a spectrometer? Um, don't hold your breath!dtsh wrote: ↑Tue May 24, 2022 6:55 pmI'd be interested in seeing that thread.LouiseScot wrote: ↑Tue May 24, 2022 6:28 pmI would expect 'white' but at a higher colour temperature than the LED and which would be variable. I suppose one advantage of an LED is that the colour temperature is fixed for a particular device. But that colour temperature will be determined by the stimulating/blue wavelength and the stimulated wavelengths determined by the emitting phosphors, I think. If I was of a mind to I could dig out my slit spectrometer, get it up and running again, and point it at some LEDs...
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
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Re: LED Illumination Comparison
I'm not sure what the purpose of including an amorphous light source such as a cloudy sky is in your comparison. Microscope condensers have a focal point and with modern microscopes it is finite rather than infinite. Older microscopes that used remote illuminators or the sky, had condensers with an infinite front focal point and a finite back focal point.
Regarding your other illuminator choices, the only image that is passably decent is the last one. It seems to have some contrast and resolution plus a degree of colour separation. There is a lot of blur. Very weak resolution in general.
It is difficult to use such heavily stained slides for any meaningful critical evaluation because you have no baseline upon which to make an evaluation.
Use unstained samples. You might check your condenser focus and diaphragm adjustments. Something is really off besides the quality of the slides.
Regarding your other illuminator choices, the only image that is passably decent is the last one. It seems to have some contrast and resolution plus a degree of colour separation. There is a lot of blur. Very weak resolution in general.
It is difficult to use such heavily stained slides for any meaningful critical evaluation because you have no baseline upon which to make an evaluation.
Use unstained samples. You might check your condenser focus and diaphragm adjustments. Something is really off besides the quality of the slides.
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Re: LED Illumination Comparison
It was just quick and dirty comparison between my diy LED add-on and the other, factory installed, LED. The mirror + sky was a bit of an afterthought just to see what the colours might be like compared to LED. Obviously there's more green and blue in daylight. The image outcomes are a good enough guide for me.apochronaut wrote: ↑Tue May 24, 2022 7:18 pmI'm not sure what the purpose of including an amorphous light source such as a cloudy sky is in your comparison. Microscope condensers have a focal point and with modern microscopes it is finite rather than infinite. Older microscopes that used remote illuminators or the sky, had condensers with an infinite front focal point and a finite back focal point.
Regarding your other illuminator choices, the only image that is passably decent is the last one. It seems to have some contrast and resolution plus a degree of colour separation. There is a lot of blur. Very weak resolution in general.
It is difficult to use such heavily stained slides for any meaningful critical evaluation because you have no baseline upon which to make an evaluation.
Use unstained samples. You might check your condenser focus and diaphragm adjustments. Something is really off besides the quality of the slides.
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
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Re: LED Illumination Comparison
Thanks Louise. You just proved that my leds are less blue than daylight. I appreciate that and have more appreciation for the lighting I have chosen, which is very similar to yours. I don't have a 680 yet and maybe never will. But my conversion of my 660 gives similar results.
Greg
Greg
Re: LED Illumination Comparison
Please forgive the pedantry, Louise … but I must point out that ‘colour temperature’ is not a particularly reliable concept when considering LED outputs. [yes, I know that suppliers quote it]LouiseScot wrote: ↑Tue May 24, 2022 6:28 pm
I would expect 'white' but at a higher colour temperature than the LED and which would be variable. I suppose one advantage of an LED is that the colour temperature is fixed for a particular device. […]
By definition, it assumes that the source is a Black Body radiator …
MichaelG.
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This is a very helpful page: https://www.lrc.rpi.edu/programs/nlpip/ ... tisCCT.asp
Too many 'projects'
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Re: LED Illumination Comparison
Thanks, yes I know - I've studied physics . But in this case it's still useful when comparing to different light sources that have variable colour temperatures.MichaelG. wrote: ↑Wed May 25, 2022 8:42 amPlease forgive the pedantry, Louise … but I must point out that ‘colour temperature’ is not a particularly reliable concept when considering LED outputs. [yes, I know that suppliers quote it]LouiseScot wrote: ↑Tue May 24, 2022 6:28 pm
I would expect 'white' but at a higher colour temperature than the LED and which would be variable. I suppose one advantage of an LED is that the colour temperature is fixed for a particular device. […]
By definition, it assumes that the source is a Black Body radiator …
MichaelG.
.
This is a very helpful page: https://www.lrc.rpi.edu/programs/nlpip/ ... tisCCT.asp
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
Re: LED Illumination Comparison
Jumping late on the wagon...
A 6000+ K cool white LED has an intense blue component. An amber filter (KR12) removes much of the blue so the output resembles a warm white LED.
This is what I have used in the past.
Recently I got a neutral white LED, 4000K or 5000K I think, that has a CRI of ~95, in a commercial retrofit to my microscope. It yields pleasantly white background, where the blue component is small.
A 6000+ K cool white LED has an intense blue component. An amber filter (KR12) removes much of the blue so the output resembles a warm white LED.
This is what I have used in the past.
Recently I got a neutral white LED, 4000K or 5000K I think, that has a CRI of ~95, in a commercial retrofit to my microscope. It yields pleasantly white background, where the blue component is small.
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Re: LED Illumination Comparison
Yeah the higher the apparent temperature the stronger (and shorter?) the blue stimulating wavelength. I went for the warm white because the blue is relatively reduced but most of the rest of the visible power spectrum output is quite good. I'm not overly bothered by how accurately colours are reproduced by the LED as they can be adjusted on camera, or post capture. I also still have the option of using a halogen bulb on the T680. Most of the specimens I might image don't have much colour anyway! It's clear that LED lighting causes colour shifts when that light is reflected from a coloured surface https://reader.elsevier.com/reader/sd/p ... 0525100155Hobbyst46 wrote: ↑Wed May 25, 2022 9:38 amJumping late on the wagon...
A 6000+ K cool white LED has an intense blue component. An amber filter (KR12) removes much of the blue so the output resembles a warm white LED.
This is what I have used in the past.
Recently I got a neutral white LED, 4000K or 5000K I think, that has a CRI of ~95, in a commercial retrofit to my microscope. It yields pleasantly white background, where the blue component is small.
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
Re: LED Illumination Comparison
Thanks for the link, Louise!
Re: LED Illumination Comparison
[quote=LouiseScot post_id=122568 time=16534733
Yeah the higher the apparent temperature the stronger (and shorter?) the blue stimulating wavelength. ...
[/quote]
Please correct me if I am wrong... But: I believe the significant difference is in the choice of phosphors, not the blue exciter.
MichaelG.
Yeah the higher the apparent temperature the stronger (and shorter?) the blue stimulating wavelength. ...
[/quote]
Please correct me if I am wrong... But: I believe the significant difference is in the choice of phosphors, not the blue exciter.
MichaelG.
Too many 'projects'
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Re: LED Illumination Comparison
Please correct me if I am wrong... But: I believe the significant difference is in the choice of phosphors, not the blue exciter.
MichaelG.
[/quote]
Yes, I think you're right, Michael! See fig 3 here https://www.digikey.co.uk/en/articles/d ... white-leds
I think I had it in my head that the blue wavelength would determine the highest apparent temperature value but it appears to be more complicated than that! Anyway, no worries.
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
Re: LED Illumination Comparison
As we’re in agreement, Louise … I am referencing this recent post from another discussion:
viewtopic.php?p=121805#p121805
purely for the benefit of any newcomers who might not immediately recognise the difference between the phosphors.
… it might make the shopping easier !!
Obviously there are different ‘recipes’ available, but the general principle is evident.
MichaelG
viewtopic.php?p=121805#p121805
purely for the benefit of any newcomers who might not immediately recognise the difference between the phosphors.
… it might make the shopping easier !!
Obviously there are different ‘recipes’ available, but the general principle is evident.
MichaelG
Too many 'projects'
Re: LED Illumination Comparison
Interesting.apochronaut wrote: ↑Tue May 24, 2022 7:18 pmMicroscope condensers have a focal point and with modern microscopes it is finite rather than infinite. Older microscopes that used remote illuminators or the sky, had condensers with an infinite front focal point and a finite back focal point.
How can I tell which type of condenser I have ? ( I think my mirror & condenser are from different sources)
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Re: LED Illumination Comparison
Some companies kept infinity corrected condenser designs from the past but any of the modern Chinese ones I have looked at are finite. An infinity corrected condenser should be just as good as a finite condenser as long as the illumination beam is parallel and köhler systems. Finite condensers are obviously better at focusing on close diverging light beams.
To check them , just set the condenser back lens at focus on a grid or piece of fabric for instance and while backing away from it, it should maintain focus from quite close to several feet and beyond. A finite condenser will have a point of focus and be increasingly blurry inside that point.
I just checked some AO condensers, a 1.3 achromat aplanat from 1925, a 1960 abbe, 1960 abbe phase condenser and 1985 abbe aspheric and they were all infinity. A good quality W.F abbe from an approx. $1500.00 Chinese infinity corrected fluorescence microscope sold by Changsa Suny was finite.
To check them , just set the condenser back lens at focus on a grid or piece of fabric for instance and while backing away from it, it should maintain focus from quite close to several feet and beyond. A finite condenser will have a point of focus and be increasingly blurry inside that point.
I just checked some AO condensers, a 1.3 achromat aplanat from 1925, a 1960 abbe, 1960 abbe phase condenser and 1985 abbe aspheric and they were all infinity. A good quality W.F abbe from an approx. $1500.00 Chinese infinity corrected fluorescence microscope sold by Changsa Suny was finite.
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Re: LED Illumination Comparison
Here are the same slides taken on the T680 with the 20W halogen bulb.
Spirogyra
Skin
Maize
I didn't use a blue filter and the bulb brightness was mostly set to about 60% max (I think!). As before all images set to 30% of actual size.
Louise
Spirogyra
Skin
Maize
I didn't use a blue filter and the bulb brightness was mostly set to about 60% max (I think!). As before all images set to 30% of actual size.
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
Re: LED Illumination Comparison
Thanks very much, I'll have an experimentapochronaut wrote: ↑Thu May 26, 2022 1:11 amSome companies kept infinity corrected condenser designs from the past but any of the modern Chinese ones I have looked at are finite. An infinity corrected condenser should be just as good as a finite condenser as long as , , ,
it has to be at least 30y old and probably a lot older ! So from your examples, makes it probable an infinity type.
Also, (from this and your notes to GerryR) I have now a better grasp on what I had been reading about Köhler, so far I have been using an led array with a thick translucent plastic block as a diffuser
Apologies to Louise for the temporary hijack of the topic
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Re: LED Illumination Comparison
No worries!SWmicro wrote: ↑Thu May 26, 2022 4:36 pmThanks very much, I'll have an experimentapochronaut wrote: ↑Thu May 26, 2022 1:11 amSome companies kept infinity corrected condenser designs from the past but any of the modern Chinese ones I have looked at are finite. An infinity corrected condenser should be just as good as a finite condenser as long as , , ,
it has to be at least 30y old and probably a lot older ! So from your examples, makes it probable an infinity type.
Also, (from this and your notes to GerryR) I have now a better grasp on what I had been reading about Köhler, so far I have been using an led array with a thick translucent plastic block as a diffuser
Apologies to Louise for the temporary hijack of the topic
Louise
A Nikon CF plan 20x; A Swift 380T; A DIY infinity corrected focus rail system with a 40x/0.65 Olympus Plan, a 10x/0.30 Amscope Plan Fluor, and a 20x/0.75 Nikon Plan Apo
Re: LED Illumination Comparison
Me threedtsh wrote: ↑Tue May 24, 2022 6:55 pmI'd be interested in seeing that thread.LouiseScot wrote: ↑Tue May 24, 2022 6:28 pmI think. If I was of a mind to I could dig out my slit spectrometer, get it up and running again, and point it at some LEDs...
Louise