Where to find these instant LED replacements?

Here you can discuss different microscopic techniques and illumination methods, such as Brightfield, Darkfield, Phase Contrast, DIC, Oblique illumination, etc.
Message
Author
Marc
Posts: 23
Joined: Thu Mar 25, 2021 1:58 am

Where to find these instant LED replacements?

#1 Post by Marc » Mon Jul 04, 2022 1:10 am

a direct G4 CREE replacement, from a chinese manofacturer. I cannot find something similar to be purchased by unities

Please, if somebody knows something similar, I would be grateful to know

Image

Characteristics (Google translator):

Color temperature: 4500K constant
Lighting power: 5W
Working voltage: 0 ~ 6 V AC
Life life: 20,000 hours
Lighting chip: CREE
Color rendering index:> 90%(can realize the color of the specimen color)
Light spacing: G4
Scope of application: 6V20W-6V30W halogen lamps can be replaced by microscope

Page: https://www.mayduly.com/index/product/d ... s-0-main-3

Greg Howald
Posts: 1125
Joined: Tue Oct 20, 2020 6:44 am

Re: Where to find these instant LED replacements?

#2 Post by Greg Howald » Mon Jul 04, 2022 2:03 am

I must admit that I have not seen that before. I hope it is up and coming.

Sansub2
Posts: 72
Joined: Wed Oct 20, 2021 3:34 pm

Re: Where to find these instant LED replacements?

#3 Post by Sansub2 » Mon Jul 04, 2022 3:37 pm

Interested in this as well. I searched all over the place and this is the best replacement I was able to find without paying arm and leg. Light in OPs post is superior. Hope to see it in AliExpress soon.

C$ 2.43 26%OFF | AC12V LED G4 Round Spotlight Bulb 2W 3W 5730 15/24leds No Flicker Range Hood Lights Replace 20W Halogen Lamp
https://a.aliexpress.com/_mLqZBcQ

ldflan
Posts: 33
Joined: Wed May 22, 2019 11:36 pm

Re: Where to find these instant LED replacements?

#4 Post by ldflan » Mon Jul 04, 2022 5:25 pm

These people may be selling them from China?

http://www.ningbomicroscope.com/ensite/ ... _1285.html

Skeptical, but interested.

Scarodactyl
Posts: 2090
Joined: Sat Mar 03, 2018 9:09 pm

Re: Where to find these instant LED replacements?

#5 Post by Scarodactyl » Mon Jul 04, 2022 5:33 pm

I've bought from Ningbo. They took my money and sent me what I ordered promptly and were easy to deal with.

User avatar
blekenbleu
Posts: 148
Joined: Tue Feb 25, 2020 5:55 pm
Location: South Carolina low country
Contact:

Re: Where to find these instant LED replacements?

#6 Post by blekenbleu » Mon Jul 04, 2022 6:34 pm

On Alibaba:
6V 5W G4 https://www.alibaba.com/product-detail/ ... 27864.html
12V 5W G6.35 https://www.alibaba.com/product-detail/ ... 58629.html

Those are merely contact URLs for Ningbo, not click + PayPal
Last edited by blekenbleu on Mon Jul 04, 2022 6:54 pm, edited 1 time in total.
Optiphot 1, 66; AO 10, 120, EPIStar, Cycloptic

AJHope
Posts: 8
Joined: Mon Jan 24, 2022 11:45 pm

Re: Where to find these instant LED replacements?

#7 Post by AJHope » Mon Jul 04, 2022 6:37 pm

Ahhh I hope you don'tge the crazy ETA I've been getting from alibaba *sighs* I'm too tired already from supply chain issues :(

Sansub2
Posts: 72
Joined: Wed Oct 20, 2021 3:34 pm

Re: Where to find these instant LED replacements?

#8 Post by Sansub2 » Mon Jul 04, 2022 8:00 pm

Scarodactyl wrote:
Mon Jul 04, 2022 5:33 pm
I've bought from Ningbo. They took my money and sent me what I ordered promptly and were easy to deal with.
Can you please let us know how you ordered it from their site? I could not find price and buy options.

BTW, how do you guys order from Alibaba for one item? :)

Scarodactyl
Posts: 2090
Joined: Sat Mar 03, 2018 9:09 pm

Re: Where to find these instant LED replacements?

#9 Post by Scarodactyl » Mon Jul 04, 2022 8:08 pm

I emailed Robert at the email address provided on the site.

Sansub2
Posts: 72
Joined: Wed Oct 20, 2021 3:34 pm

Re: Where to find these instant LED replacements?

#10 Post by Sansub2 » Mon Jul 04, 2022 11:09 pm

Thanks Scarodactyl

Marc
Posts: 23
Joined: Thu Mar 25, 2021 1:58 am

Re: Where to find these instant LED replacements?

#11 Post by Marc » Tue Jul 05, 2022 2:19 am

thank you ldflan, Scarodactyl for that site :)

User avatar
imkap
Posts: 413
Joined: Thu Nov 25, 2021 9:44 pm

Re: Where to find these instant LED replacements?

#12 Post by imkap » Tue Jul 05, 2022 12:21 pm

This looks great, thanks. I was just wondering about direct replacement LEDs for the Axiolab I got, would be nice to compare with halogen without too much fiddling in a same setup. Shame they are all 6v as 12V are easily found. Not sure why is that...

The Axiolab has some 'light magnifying' lens in the base, so it has more light with weaker bulbs, unlike my GFL which has a plain glass, so a lot more power is needed for the same amount of light... Halogen heat a lot, so not nice to use in the summer.

User avatar
blekenbleu
Posts: 148
Joined: Tue Feb 25, 2020 5:55 pm
Location: South Carolina low country
Contact:

Re: Where to find these instant LED replacements?

#13 Post by blekenbleu » Tue Jul 05, 2022 1:10 pm

Not to be a wet blanket, but despite increasing LED efficacy,
using one of these to replace a 20W halogen lamp at nearly full intensity
in many microscopes could be problematic without an additional heat sink.
For example, my Labophot's base has highly restricted airflow to its lamp.
Optiphot 1, 66; AO 10, 120, EPIStar, Cycloptic

Scarodactyl
Posts: 2090
Joined: Sat Mar 03, 2018 9:09 pm

Re: Where to find these instant LED replacements?

#14 Post by Scarodactyl » Tue Jul 05, 2022 2:43 pm

This is a good point. I've set up a couple of stereo microscopes with cree XM-L2 LEDs, and even only running at ~6w they do warm up the chonk of aluminum I generally use as a heat sink. That said it may not be impossible to overcome with a heat sink on the back.

Sansub2
Posts: 72
Joined: Wed Oct 20, 2021 3:34 pm

Re: Where to find these instant LED replacements?

#15 Post by Sansub2 » Tue Jul 05, 2022 4:39 pm

That is a very good point. Unless someone try it, we wouldn't know as there is not much review about it online. I converted one of the scopes with XHP 70.2. Used the heatsink from old motherboard. That thing gets hot within seconds. If we have to setup with heatsink, that will defeat the intended purpose.

BTW, FYI for others, I emailed Robert. One piece is 15$, min. 50 pieces ( if I understood MOQ correctly) and 66$ shipping for Canada. So, no go. Hope it will show up in AliExpress soon for me to try.

User avatar
blekenbleu
Posts: 148
Joined: Tue Feb 25, 2020 5:55 pm
Location: South Carolina low country
Contact:

Re: Where to find these instant LED replacements?

#16 Post by blekenbleu » Tue Jul 05, 2022 4:49 pm

Scarodactyl wrote:
Tue Jul 05, 2022 2:43 pm
it may not be impossible to overcome with a heat sink on the back.
An Optiphot 66 diascopic illuminator uses a 40mm shaft to locate its G4 lamp:
G4halogen.jpg
G4halogen.jpg (44.78 KiB) Viewed 832 times
A solid 20mm long half-round would kill what little convection is possible.
Perhaps cutting down a 40mm finned heatsink..
Image
Optiphot 1, 66; AO 10, 120, EPIStar, Cycloptic

User avatar
blekenbleu
Posts: 148
Joined: Tue Feb 25, 2020 5:55 pm
Location: South Carolina low country
Contact:

Re: Where to find these instant LED replacements?

#17 Post by blekenbleu » Tue Jul 05, 2022 5:43 pm

Sansub2 wrote:
Tue Jul 05, 2022 4:39 pm
I emailed Robert. One piece is 15$, min. 50 pieces ( if I understood MOQ correctly) and 66$ shipping for Canada.
So, no go. Hope it will show up in AliExpress soon for me to try.
Alternatives pondered involve this US$8 constant current buck regulator:
Image
https://www.amazon.com/dp/B07J9RQ8B6
(I used this previously with hobby servos.)

... and Cree or Samsung CRI 90+ LED on DTP Copper MCPB, e.g. from kaidomain.com
LEDcopperMCPCB.jpg
LEDcopperMCPCB.jpg (10.99 KiB) Viewed 821 times
http://kaidomain.com/search&search=high%20cri
... also with finned heatsink.
Given typical microscope collector optics, LED without diffuser lens is wanted...?
Optiphot 1, 66; AO 10, 120, EPIStar, Cycloptic

BramHuntingNematodes
Posts: 1421
Joined: Tue Jan 21, 2020 1:29 am
Location: Georgia, USA

Re: Where to find these instant LED replacements?

#18 Post by BramHuntingNematodes » Tue Jul 05, 2022 5:59 pm

You're gonna want as small a single.die as can deliver the light. The picture looks like an array, which might benefit from a diffuser in some setups.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

User avatar
imkap
Posts: 413
Joined: Thu Nov 25, 2021 9:44 pm

Re: Where to find these instant LED replacements?

#19 Post by imkap » Tue Jul 05, 2022 9:04 pm

3-4w LED might be ok without a heatsink... That should be similar in brightness as a 20w halogen.
My 18v 10w CREE, warms up at max but nothing spectacular, no where near a halogen. I rarely crank it up, but did test it and still works. 'Heatsink' is an aluminium rod maybe 80mm long and 25mm diameter.

User avatar
imkap
Posts: 413
Joined: Thu Nov 25, 2021 9:44 pm

Re: Where to find these instant LED replacements?

#20 Post by imkap » Tue Jul 05, 2022 9:05 pm

BramHuntingNematodes wrote:
Tue Jul 05, 2022 5:59 pm
You're gonna want as small a single.die as can deliver the light. The picture looks like an array, which might benefit from a diffuser in some setups.
Why is a smallest die needed? Thanks

Marc
Posts: 23
Joined: Thu Mar 25, 2021 1:58 am

Re: Where to find these instant LED replacements?

#21 Post by Marc » Tue Jul 05, 2022 9:17 pm

Sansub2 wrote:
Tue Jul 05, 2022 4:39 pm
BTW, FYI for others, I emailed Robert. One piece is 15$, min. 50 pieces ( if I understood MOQ correctly) and 66$ shipping for Canada. So, no go. Hope it will show up in AliExpress soon for me to try.
what a pity.

I know another LED G4 at 6V, although only 1w. Far from previous model with 5w CREE.

In this model (cost 3$) the seller announces efficacy 100lm/W with the lens (who knows), and "minimal order: 10", if I understand well. However, voltage is announced "6v" instead 0-6v. I wonder if dimmable.

I will wait also for something more powerful. Anyway I leave here in case somebody is interested.

Image

https://www.alibaba.com/product-detail/ ... 9.html?s=p

Don't know more G4 at 6V. Strange these are so difficult to find.

User avatar
blekenbleu
Posts: 148
Joined: Tue Feb 25, 2020 5:55 pm
Location: South Carolina low country
Contact:

Re: Where to find these instant LED replacements?

#22 Post by blekenbleu » Tue Jul 05, 2022 9:42 pm

imkap wrote:
Tue Jul 05, 2022 9:05 pm
BramHuntingNematodes wrote:
Tue Jul 05, 2022 5:59 pm
You're gonna want as small a single.die as can deliver the light. The picture looks like an array, which might benefit from a diffuser in some setups.
Why is a smallest die needed? Thanks
I read that illumination source ideally fills objective back focal plane field.
That Cree is an array of 4 tightly packed chips, wired differently for 3/6/12V;
I guess it should be OK with Köhler alignment,
better than something like:
triad.jpg
triad.jpg (9.32 KiB) Viewed 767 times
Optiphot 1, 66; AO 10, 120, EPIStar, Cycloptic

Scarodactyl
Posts: 2090
Joined: Sat Mar 03, 2018 9:09 pm

Re: Where to find these instant LED replacements?

#23 Post by Scarodactyl » Tue Jul 05, 2022 10:06 pm

Light from the periphery of a larger emitter tends not to make it to the subject--it ends up scattering off. That said one of these 2x2s might be fine and I'm kins of curious to try one.

Sansub2
Posts: 72
Joined: Wed Oct 20, 2021 3:34 pm

Re: Where to find these instant LED replacements?

#24 Post by Sansub2 » Tue Jul 05, 2022 10:10 pm

I have done the upgrade before using the following components. Even though it worked well and gave me option to have the led of my choice, it is too cluttered, unsightly and require considerable amount of work. A simple plug and play with 5w LED is more than enough for most case.

1. Light
C$ 6.03 10%OFF | CREE XHP50 XHP70 XHP50.2 XHP70.2 2 generation Cool White Neutral White Warm White LED Emitter 6V 12V with 16mm 20mm Copper PCB
https://a.aliexpress.com/_mKzOLMO

2. Controller
C$ 2.42 42%OFF | LED Dimmer Switch DC 12V 24V 8A Adjustable Brightness Lamp Bulb Strip Driver Single Color Light Power Supply Controller
https://a.aliexpress.com/_mPdS6rs

3. Holder:
C$ 1.24 7%OFF | 5-50PCS MR16 MR11 GU5.3 G4 Lamp Holder Bulb Base with Wire Ceramic Halogen Socket Pottery Connector 12V - 250V Led Light New JQ
https://a.aliexpress.com/_mKj6IqW

4. Connector (optional)
C$ 2.25 20%OFF | 5pcs Female +5 pcs Male DC Connector 2.1*5.5mm Power Jack Adapter Plug Cable Connector For 3528/5050/5730 LED Strip Light
https://a.aliexpress.com/_mtMla5y

5. Switch:

C$ 0.63 1%OFF | 5/10Pcs Push Button Switch 10x15mm SPST 2Pin 3A 250V KCD11 Snap-in on/Off Rocker Switch 10MM*15MM Black Red and White
https://a.aliexpress.com/_mLmg8rg

6. 12v power brick - used the one I already had

7. Heatsink - pulled it from old motherboard
8. Thermal paste.
Noctua NT-H1 3.5g, Pro-Grade Thermal Compound Paste (3.5g) https://a.co/d/3ri11lH

User avatar
imkap
Posts: 413
Joined: Thu Nov 25, 2021 9:44 pm

Re: Where to find these instant LED replacements?

#25 Post by imkap » Tue Jul 05, 2022 10:43 pm

Scarodactyl wrote:
Tue Jul 05, 2022 10:06 pm
Light from the periphery of a larger emitter tends not to make it to the subject--it ends up scattering off. That said one of these 2x2s might be fine and I'm kins of curious to try one.
I understand thanks, I have one like this it is 9mm. 18-19V PSUs with 3A+ are easy to come by from retired laptops.
https://hr.mouser.com/ProductDetail/941-CXB1512F0BP440E

There is some halo around the iris hole when i close it down, not sure why. Although I don't remember seeing it when I first installed this LED. I have another one with a bit lesser lumens rating and 90 CRI, I'll try it next, but first I'll make another aluminium rod, so I can compare side by side...

BramHuntingNematodes
Posts: 1421
Joined: Tue Jan 21, 2020 1:29 am
Location: Georgia, USA

Re: Where to find these instant LED replacements?

#26 Post by BramHuntingNematodes » Tue Jul 05, 2022 10:50 pm

The theoretical ideal light source is a single point and a field lens of the right size and focal length. Filaments and arcs would approximate these. As the na of your objective increases, the amount.of surface area from your light source you can use.to collect light diminishes, even with an ideal field lens. The smaller your source is, then, the less this matters.

The three up chip is the least suitable as you will end up fixing on one of the three LEDs for the most even illumination on higher magnifications. Using a diffuser wont help the situation. In fact an advantage of LEDs is that they can be so small that diffusers can be eliminated entirely.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

User avatar
blekenbleu
Posts: 148
Joined: Tue Feb 25, 2020 5:55 pm
Location: South Carolina low country
Contact:

Re: Where to find these instant LED replacements?

#27 Post by blekenbleu » Fri Jul 08, 2022 12:15 am

Scarodactyl wrote:
Tue Jul 05, 2022 10:06 pm
one of these 2x2s might be fine and I'm kind of curious to try one.
Optiphot and Labophot lamp electronics,
which drive a halogen lamp using a power transistor,
can be repurposed to drive one of those,
since transistors are essentially current amplifiers.
Increasing resistance to the transistor's base can limit
collector current to values appropriate
for e.g. Cree 6V 3A CRI90 COB LEDs,
which should deliver over 1000 lm @ 1.5A.
Their active area appears to be about 3mm square,
roughly the same as a G4 halogen filament's long dimension.
XHP50.3.jpg
XHP50.3.jpg (23.71 KiB) Viewed 645 times
https://cree-led.com/media/documents/XLamp-XHP50.3.pdf
Optiphot 1, 66; AO 10, 120, EPIStar, Cycloptic

MichaelG.
Posts: 3483
Joined: Mon Apr 10, 2017 8:24 am
Location: NorthWest England

Re: Where to find these instant LED replacements?

#28 Post by MichaelG. » Fri Jul 08, 2022 6:36 am

Thanks for that link, blekenbleu

I have just downloaded its 46 pages for bedtime reading.
… they look very promising indeed !

MichaelG.
Too many 'projects'

User avatar
blekenbleu
Posts: 148
Joined: Tue Feb 25, 2020 5:55 pm
Location: South Carolina low country
Contact:

Re: Where to find these instant LED replacements?

#29 Post by blekenbleu » Fri Jul 08, 2022 1:04 pm

MichaelG. wrote:
Fri Jul 08, 2022 6:36 am
they look very promising
For some materials, appearance differences between 90 and 95 CRI are significant;
whether CRI is an appropriate metric is also arguable.
https://www.candlepowerforums.com/threa ... es.415041/
D50 (~5000K) is the traditional graphic arts color temperature;
whether photomicography color rendering is standardized seems unclear.
https://micro.magnet.fsu.edu/primer/pho ... lters.html
Optiphot 1, 66; AO 10, 120, EPIStar, Cycloptic

BramHuntingNematodes
Posts: 1421
Joined: Tue Jan 21, 2020 1:29 am
Location: Georgia, USA

Re: Where to find these instant LED replacements?

#30 Post by BramHuntingNematodes » Fri Jul 08, 2022 3:29 pm

3mm should be fine that disc mount must be quite small
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

Post Reply