Search found 2482 matches

by mawyatt
Sat Aug 01, 2020 2:03 pm
Forum: General Discussion Forum and Community Announcements
Topic: Why aren't flies blinded by the sun?
Replies: 6
Views: 145

Re: Why aren't flies blinded by the sun?

Wonder if they have a type of structure where the light transmission varies with intensity, like the sunglasses that get dark when exposed to bright light, then return to somewhat clear when the intensity drops?

Best,
by mawyatt
Wed Jul 29, 2020 8:48 am
Forum: Equipment Discussions
Topic: best controller for THK KR2
Replies: 7
Views: 257

Re: best controller for THK KR2

When these controllers coupled with the superb THK rails KR15, 20 and 26 with quality 400 step motors you have, think this is the SOTA for stepper based focus rails. Probably true, but I got the sense that the OP was looking for a more plug and play solution like I was when I bought the mjkzz contr...
by mawyatt
Wed Jul 29, 2020 8:01 am
Forum: Equipment Discussions
Topic: best controller for THK KR2
Replies: 7
Views: 257

Re: best controller for THK KR2

Ray, Think the Trinamic device you have/had is an old device and not the same as what we've recently (past few years) developed based upon the modern TMC5130, 5160 and 5072 BOB devices. The hardware motor driver and micro controller are integrated on the same chip, as is the interface. This is a com...
by mawyatt
Tue Jul 28, 2020 12:40 pm
Forum: Equipment Discussions
Topic: best controller for THK KR2
Replies: 7
Views: 257

Re: best controller for THK KR2

Check out the many threads on the Trinamic Controllers, they are superb with the THK KR20. The TMC5130, TMC5160 and TMC5072 all work well with the THK KR20.

Best,
by mawyatt
Sun Jul 12, 2020 6:28 am
Forum: Equipment Discussions
Topic: Godox 150W Video LED Light
Replies: 8
Views: 2322

Re: Godox 150W Video LED Light

I looked at the video which was linked in Mike's most recent post. Youtube took me down the rabbit hole to a more recent video by the same equipment reviewer. It seems that Godox have a new 150W LED video light, the UL150. This is silent. The video claims that it is cooled entirely passively. This ...
by mawyatt
Sun Jul 12, 2020 6:08 am
Forum: Equipment Discussions
Topic: Godox 150W Video LED Light
Replies: 8
Views: 2322

Re: Godox 150W Video LED Light

Nice to stumble across this thread again as I just picked up the Godox SL-60W. While not as the same as this one, it's good to know Godox's claims hold up and to have some data on the output with different attachments. The "snoot" was a standard black anodized aluminum Bowens type ~200mm snoot with...
by mawyatt
Fri Jul 10, 2020 4:54 pm
Forum: Equipment Discussions
Topic: Godox 150W Video LED Light
Replies: 8
Views: 2322

Re: Godox 150W Video LED Light

Yes it could have been the newer model, but without getting another SL-150W now, have no way of knowing. We have 3 and they are all the same, and use the LED COB & heatsink shown above and the hefty power supply shown, all well above what you would expect. They also work nice in flash strobe mode wi...
by mawyatt
Wed Jul 08, 2020 4:54 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: When DMAP and stereos shine! New pics added.
Replies: 14
Views: 459

Re: When DMAP and stereos shine! New pics added.

Beatsy wrote:
Wed Jul 08, 2020 2:51 pm
mawyatt wrote:
Wed Jul 08, 2020 9:08 am
...Another option, maybe not so awful looking is the Heyjar Lens support...
Thanks for the pointer, but I can't find anything support-like under "Heyjar" on Google. Do you have a link pls? Ta.
My bad, it's Hejnar Photo.


https://www.hejnarphotostore.com

Best,
by mawyatt
Wed Jul 08, 2020 9:08 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: When DMAP and stereos shine! New pics added.
Replies: 14
Views: 459

Re: When DMAP and stereos shine! New pics added.

Nice work, really like the stereo view. Agree it just "jumps" out to show the 3D effect. Is that a Wemacro lens holder on the "tube lens" which looks like a Nikon 200mm F3.5? Thanks. I can't find any brand on the lens! I call it "generic M42" but it is 200/3.5 so you may have solved a mystery. Yes,...
by mawyatt
Wed Jul 08, 2020 6:57 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: When DMAP and stereos shine! New pics added.
Replies: 14
Views: 459

Re: When DMAP and stereos shine! New pics added.

Nice work, really like the stereo view. Agree it just "jumps" out to show the 3D effect.

Is that a Wemacro lens holder on the "tube lens" which looks like a Nikon 200mm F3.5?

Best,
by mawyatt
Tue Jul 07, 2020 2:36 pm
Forum: Equipment Discussions
Topic: Linear stage with 3.3" travel, stepper motor, and 0.5 micron encoder for about $100
Replies: 17
Views: 751

Re: Linear stage with 3.3" travel, stepper motor, and 0.5 micron encoder for about $100

We have traveled rather far from the hardware at hand, and I don't want to mislead those potentially interested. The encoder on this hardware is linear, high resolution and appropriate for the majority of photomacrography purposes (>3" travel and practical resolution around 1um which should be suff...
by mawyatt
Tue Jul 07, 2020 10:56 am
Forum: Equipment Discussions
Topic: Linear stage with 3.3" travel, stepper motor, and 0.5 micron encoder for about $100
Replies: 17
Views: 751

Re: Linear stage with 3.3" travel, stepper motor, and 0.5 micron encoder for about $100

I think in the sub µm range the problem is no longer the motor but stick-slip phenomena of the spindel/nut. May be the ball screw of the THK KR series has an edge over all the thread screw spindels. But probably such small movements with high accuracy and repeatability are the domain of piezo posit...
by mawyatt
Tue Jul 07, 2020 6:13 am
Forum: Equipment Discussions
Topic: Trinamic parameter tuning
Replies: 5
Views: 289

Re: Trinamic parameter tuning

Can the Stallguard value be found by starting low so that the motor stalls and then increasing the vale until it moves? I think I've found that the behaviour is different depending on whether you are going clockwise or anticlockwise! I've noticed this too, one direction runs slightly slower than th...
by mawyatt
Sun Jul 05, 2020 11:11 am
Forum: Equipment Discussions
Topic: Linear stage with 3.3" travel, stepper motor, and 0.5 micron encoder for about $100
Replies: 17
Views: 751

Re: Linear stage with 3.3" travel, stepper motor, and 0.5 micron encoder for about $100

We don't use the Toshiba devices but was told about them, were using some of the TI devices which were all replaced. Feedback doesn't "cure" backlash, it only masks the effects, sometimes making it worse. The dead zone caused by backlash creates "hunting" in closed loop systems, this can cause consi...
by mawyatt
Sun Jul 05, 2020 10:13 am
Forum: Equipment Discussions
Topic: Trinamic parameter tuning
Replies: 5
Views: 289

Re: Trinamic parameter tuning

Can the Stallguard value be found by starting low so that the motor stalls and then increasing the vale until it moves? I think I've found that the behaviour is different depending on whether you are going clockwise or anticlockwise! Don't know, probably best to study the Trinamic documentation. We...