Search found 2488 matches

by mawyatt
Tue Mar 10, 2020 6:22 pm
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

Next (so we can keep track of things). What is your simulation model with your "circuit" for the load? And this is the critical part for all other accusation :D If you have a COB LED, go through the exercise I mentioned, plot a chart with voltage and current on it. After you finish that, you will s...
by mawyatt
Tue Mar 10, 2020 4:48 pm
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

THIS ACTUALLY IS THE BASE of my suggestion that you can not use it on all LEDs and I kept calling out for the LED model you used in your "circuit". Peter, If the "circuit" you reference is the "Fast LED Strobe for Macro" thread https://www.photomacrography.net/forum/viewtopic.php?t=40999 This is cu...
by mawyatt
Tue Mar 10, 2020 1:10 pm
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

Think about the work of James Maxwell, or Albert Einstein, or Issac Newton, they had no means to do hands on. Maxwell's 4 fundamental equations describing all EM phenomena, Einstein's Relativity & Gravitional Waves, Newtons laws, and so many more concrete contributions to human understanding, all d...
by mawyatt
Tue Mar 10, 2020 12:21 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Sample density needed to resolve Rayleigh features
Replies: 40
Views: 6256

In communications (where these theorems originated) recent work has been pushing the limits beyond Nyquist. Most have thought of Nyquist as a limit, but as far back as 1975 Mazo at Bell Labs had shown it is not an absolute limit barrier, but could be "broken" in fact under certain signaling conditi...
by mawyatt
Tue Mar 10, 2020 10:38 am
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

Chris, Agree that theory and hands on are the best approach, maybe not in that order tho :D Recall an incredibly complex system we were developing back in 80s, so advanced that we had to develop out own test equipment! We had created a new type clocking driver for some CCD chips we had developed, th...
by mawyatt
Tue Mar 10, 2020 8:34 am
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

This thread is about concrete stuff, with specific model number of devices, let me be polite and suggest you to get one of those devices, plot some chart with voltage and current, use your scope (if you really have one) and do some hands on experiment, make some concrete contribution. PLEASE. BTW, ...
by mawyatt
Tue Mar 10, 2020 8:06 am
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

OK, I am going to try to be peaceful :-) Please do the following: Put your COB in 200mA state, take a note on voltage, then increase it by 59mV, see what you got on current. Maybe do a plot for every 50mA from start to, maybe 1000mA, since LEDs are current device. Do you see any reason for those ri...
by mawyatt
Mon Mar 09, 2020 6:04 pm
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

Mike, as we all know, you need certain voltage potential for a diode to conduct. At that critical point, typically 0.7V, from non-conducting to conducting, you have current change of infinity. "your theory" means you threw out that thing in the discussion. I really doubt you are the inventor/discov...
by mawyatt
Mon Mar 09, 2020 11:48 am
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

I am not going to quote what you said, it is too long. Please do not take my previous comment negatively, a lot of your talk are sound, professional, reflecting your experience. But sometimes, I feel like your comments are a bit far fetched, but backed with heavy reading references to make it look ...
by mawyatt
Sun Mar 08, 2020 7:29 pm
Forum: Equipment Discussions
Topic: Faulhaber motor on the THK KR26
Replies: 2
Views: 801

Those are DC motors and won't work with a stepper motor controller. You will need to get a DC motor controller, or replace the motor with a stepper motor and use a stepper motor controller like you mentioned.

Best,
by mawyatt
Sun Mar 08, 2020 6:49 pm
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

I am a little math phobia, I'd rather deal with physical things than those symbols :D And maybe, just maybe it is beneficial for you to get a power LED and experiment with it, it actually is a lot of fun and since you like to tinker. Agree it would be fun to play with the power LEDs when/if time pe...
by mawyatt
Sun Mar 08, 2020 10:14 am
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

I am a little math phobia, I'd rather deal with physical things than those symbols :D And maybe, just maybe it is beneficial for you to get a power LED and experiment with it, it actually is a lot of fun and since you like to tinker. Agree it would be fun to play with the power LEDs when/if time pe...
by mawyatt
Sun Mar 08, 2020 8:37 am
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

Therefore, those small ripples would not cause sudden change in power output, significantly enough to cause flickering. For example, if I crank up voltage to 9.5V from 8.85V, current goes up from 0.1A to about 0.3A. Those ripples looks like less than 10mV. This equates to ~2 ohms total series LED r...
by mawyatt
Sat Mar 07, 2020 6:45 pm
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

Interesting videos!!

The Fast LED Strobe design we presented should have no trouble keeping up and synching with a 1000 frames per second (1ms) camera.

https://www.photomacrography.net/forum/ ... hp?t=40999

Best,
by mawyatt
Sat Mar 07, 2020 6:33 pm
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 8065

LEDs are fundamentally semiconductor junctions and have a exponential relationship between current & voltage. You may need to measure/see the LED current, not the LED voltage, which might be contributing to the flicker. Place a small (~1 ohm ~1 watt) resistor in series with the LED and monitor the ...