LED Illumination Comparison

[SWmicro]

I thought I'd post a quick comparison

Are there any clear areas on the slides or are they all coloured a bit ?
Assuming the circled area is such a clear area I have out of curiosity chosen it to be a "white balance " point in IrfanView (quicker to use and more gentle than Gimp !)
Using your filenames for ref :

LouiseWB-Hal Spiro 10x_00001_30pc.jpg (57.87 KiB) Viewed 3202 times

LouiseWB-T720 Spiro 10x_00002_30pc.jpg (64.33 KiB) Viewed 3202 times

[LouiseScot]

I thought I'd post a quick comparison

Are there any clear areas on the slides or are they all coloured a bit ?
Assuming the circled area is such a clear area I have out of curiosity chosen it to be a "white balance " point in IrfanView (quicker to use and more gentle than Gimp !)
Using your filenames for ref :

Hi

Um, I didn't do any extra colour processing on any of the images as I wanted just to compare the colours obtained from the different LEDs and the Halogen. Clearly I could have adjusted the colours in many ways but it would have taken me down a rabbit hole! Thanks for your efforts anyway.

Louise

[SWmicro]

I thought I'd post a quick comparison

Are there any clear areas on the slides or are they all coloured a bit ?
Assuming the circled area is such a clear area I have out of curiosity chosen it to be a "white balance " point in IrfanView (quicker to use and more gentle than Gimp !)
Using your filenames for ref :

just to compare the colours obtained from the different LEDs and the Halogen.

Yes indeed, I get that, hence me wondering if there was a clear area on that slide, to look at only the light source colour, or is there a smear of stain over it all ? (Just curios, nowt on telly and it is all doom anyhow !! )

[LouiseScot]

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

I'd be interested in seeing that thread.

Me three

Sorry, it's not going to happen! It would take too much time and effort to reassemble it, set it up etc. It was intended for acquiring spectra from individual stars though I did acquire some from various light sources e.g. a (cfl) fluorescent bulb, a nitrogen discharge tube and others. It's been over 2 years since I last fiddled with it... The output would likely not be very helpful here, anyway.

Louise

[SWmicro]

I'd be interested in seeing that thread.

Me three

would likely not be very helpful here, anyway.

possibly not but would be fun Shhh dont tell anyone but my Canon 60d that I am using on the microscope is astro modified for Ha

[LouiseScot]

Are there any clear areas on the slides or are they all coloured a bit ?
Assuming the circled area is such a clear area I have out of curiosity chosen it to be a "white balance " point in IrfanView (quicker to use and more gentle than Gimp !)
Using your filenames for ref :

just to compare the colours obtained from the different LEDs and the Halogen.

Yes indeed, I get that, hence me wondering if there was a clear area on that slide, to look at only the light source colour, or is there a smear of stain over it all ? (Just curios, nowt on telly and it is all doom anyhow !! )

Hi

I think there's not much point in looking at the existing images which are only jpegs anyway. Where there is no specimen visible the slides were clear. I think some of them, at least, might have been a bit overexposed as the usb2 Toupcam is limited in terms of exposure settings and I just wanted to do the quick comparison. I'll probably set up a dslr or mirrorless camera to do some better images. I've since upgraded some of the objectives to Nikon fluors on the T680 and changed some on the T720 also, including a 10x PlanF. I'm looking to get some more plan fluors for the T720.

Louise

[LouiseScot]

Me three

would likely not be very helpful here, anyway.

possibly not but would be fun Shhh dont tell anyone but my Canon 60d that I am using on the microscope is astro modified for Ha

I have a modded 1100D
* full spectrum

[SWmicro]

* full spectrum

Oh that was brave
ideal for quantifying the light from an LED after it has passed through a spectrum analyser lol!

[LouiseScot]

* full spectrum

Oh that was brave
ideal for quantifying the light from an LED after it has passed through a spectrum analyser lol!

At the time I wanted to take non-astro images in UV but I also have actual mono astro cameras now. I used a 20MP QHY183Mono to capture spectra but one day I suddenly put it all to one side and never got back to it! Typical of me! So I started doing some microscopy again instead... I might conceivably get back to doing some spectroscopy again one day - if the mood takes me.

Louise

[Hobbyst46]

* full spectrum

Oh that was brave
ideal for quantifying the light from an LED after it has passed through a spectrum analyser lol!

At the time I wanted to take non-astro images in UV but I also have actual mono astro cameras now. I used a 20MP QHY183Mono to capture spectra but one day I suddenly put it all to one side and never got back to it! Typical of me! So I started doing some microscopy again instead... I might conceivably get back to doing some spectroscopy again one day - if the mood takes me.

Louise

There is a special charm of combining knowledge, experience and technique from different fields.
Even mating the relatively trivial experience with LEDs to home microscopy...

[LouiseScot]

Oh that was brave
ideal for quantifying the light from an LED after it has passed through a spectrum analyser lol!

At the time I wanted to take non-astro images in UV but I also have actual mono astro cameras now. I used a 20MP QHY183Mono to capture spectra but one day I suddenly put it all to one side and never got back to it! Typical of me! So I started doing some microscopy again instead... I might conceivably get back to doing some spectroscopy again one day - if the mood takes me.

Louise

There is a special charm of combining knowledge, experience and technique from different fields.
Even mating the relatively trivial experience with LEDs to home microscopy...

Indeed, but perhaps that's why I'm a Jack of all trades - ha ha!
Louise

[SWmicro]

I might conceivably get back to doing some spectroscopy again one day - if the mood takes me.

Yes, that's what hobbies are all about, I have lots of the T shirts
If you do we will, as always, be interested !

[LouiseScot]

I fitted a dslr (Canon 1100d) to the T720 and took some pics with the infinity PlanF 10x/0.30. It's definitely a more satisfying experience using a dslr vs the 5MP Toupcam!
I always manage to mess up colour adjustments and things never seem to quite come out right when I attempt them.. I think I'm past it! Oh well.

Anyway, here's the human skin section (which has become a bit greenish in places!). There's some slight vignetting in the left hand corners but that disappears with a crop.


Most of the frame but with the right hand cropped out as it was empty:

Skin_PlanF10xFlipCropStretch3_0023.jpg (234.47 KiB) Viewed 3040 times

Crop to roughly match the other images of the same slide:

Skin_PlanF10xFlipCrop45pcStretch_0023.jpg (160.16 KiB) Viewed 3040 times

Louise

[Hobbyst46]

To my eyes the images are nicely sharp coast to coast within the limitation of flatness of the specimen as prepared.

Vignetting is probably because of very slight deviation from coaxiality.

BTW, my Toupcam eyepiece camera (cost ~ 70USD) produced pretty sharp images, after (each time) very careful adjustment of focus, which always deviated from the focus through the eyepieces. Far less planar than your DSLR images, though.

[LouiseScot]

To my eyes the images are nicely sharp coast to coast within the limitation of flatness of the specimen as prepared.

Vignetting is probably because of very slight deviation from coaxiality.

BTW, my Toupcam eyepiece camera (cost ~ 70USD) produced pretty sharp images, after (each time) very careful adjustment of focus, which always deviated from the focus through the eyepieces. Far less planar than your DSLR images, though.

Hiya

The vignetting is caused by the light path being restricted by a narrow coupling to the trinocular head. It only shows up at <20x objective mag. I can probably improve on it with a different adapter, when I can get around to it... My eyesight and my visual judgement are pretty rubbish these days But I'll keep at it to the bitter end! Which Toupcam do you have? Mine is an old usb2 5MP which is very slow and only allows certain exposure values. The 1100d with live view is so much better!

Louise

[Hobbyst46]

Which Toupcam do you have? Mine is an old usb2 5MP which is very slow and only allows certain exposure values.

Same as mine I think. An unbranded USB2 5MP, 2592x1944, frame rate - 15 fps for Mpegs and 2 fps for YU2U. Even at 1280x760 (YU2U) it only yields 5 fps...but I almost never record videos, so OK for now.

[Greg Howald]

Seems your 680 halogen images are of inferior quality when compared to your led images. Greg

[LouiseScot]

Seems your 680 halogen images are of inferior quality when compared to your led images. Greg

Yeah, seems like it. Maybe because of more red or a generally wider spectrum from the halogen? Objectives were only achromats for those original T680 images. I've since upgraded to the Nikon plan 20 CF and Nikon 40x plan fluor, and the 100x UV F100 glycerol immersion lenses. The 4x and 10x are now the ones from my Swift - hopefully better than the originals but not tried yet. jmc has been inspiring me to have another go with glycerin immersion imaging of diatoms. It must be over a year since I last had a go with short wavelength light and a mono camera. I might make do with a 486nm filter this time else bypass the Kohler illuminator.

Louise

[LouiseScot]

Which Toupcam do you have? Mine is an old usb2 5MP which is very slow and only allows certain exposure values.

Same as mine I think. An unbranded USB2 5MP, 2592x1944, frame rate - 15 fps for Mpegs and 2 fps for YU2U. Even at 1280x760 (YU2U) it only yields 5 fps...but I almost never record videos, so OK for now.

Mine also very slow when changing settings or using auto exposure or auto white balance. Drives me nuts!
Louise

[viktor j nilsson]

On my Canon 5D mark II, I usually take a photo of a blank slide after setting up Kohler in brightfield, and then use the photo to set a custom white balance profile. I find it very easy and reliable.

[LouiseScot]

On my Canon 5D mark II, I usually take a photo of a blank slide after setting up Kohler in brightfield, and then use the photo to set a custom white balance profile. I find it very easy and reliable.

Thanks. I had thought of trying that. It's probably better than me being lazy and just using 'auto'...

Louise