19 replies to this topic

[Polyphemos]

I recently sent in my FarPoint purchased Lumicon UHC Gen 3 filter to Silicon Valley Optical Technology, Inc. (SVOTek) for spectrum analysis. I was concerned that FarPoint may have sourced my filter from China, and that it might not meet published specifications. The results are as follows:

 

 

Test results were transmitted under this email from SVOTek:

 

 

And so it appears my filter was manufactured by SVOTek, and that it does meet specifications. Other filters sold by FarPoint under the Lumicon name did not meet specifications, like this Oiii filter for example:

 

 

The particulars behind this filter were sent in an email to the owner, a part of which is as follows:

 

“After inspecting the filter you sent us:

 

1. We have replaced your ring with a brand new one, so your filter should be good to go. We will ship you the filter soon with a tracking number.

 

2. We would like to inquire: from which vendor did you purchase this filter from?

 

While repairing your filter, we noticed that the ring design did not match our own. Additionally, our engineers did a filter spectrum analysis and discovered that there is a discrepancy in the transmission graph. Per our website, the Lumicon O-III filter transmission should be > 90% from 496.5 nm - 501.5nm, with a peak at 498.5 += 2nm wavelength. However, this filter peaks at 492 nm which misses the spec by a significant 6 nm, something our strict qualify control would have caught far before it reached shipment. The filter has at best 10% effectiveness compared to its specs.

 

We are concerned that you may have been misled about the authenticity of this filter. There have been many counterfeit Lumicon products as of late, and we fear that their poor quality will tarnish the Lumicon brand and legacy.

 

Thank you,

Andrew
Lumicon Inc.”

 

If you have concerns about the authenticity of your own Lumicon filters, and particularly about those sold by FarPoint, SVOTek has offered to test Lumicon branded filters free of charge. I do not know how long this offer might stand, and you will need to provide a postage paid return label if you’d like your filter back after testing. You can find contact information for this service on the SVOTek website at:

 

http://www.svotek.com/
 

Good Luck!

Edited by Polyphemos, 08 February 2024 - 10:47 PM.

[AstroApe]

Oh wow, thanks for sharing this. There's been some rumors going around about Farpoint & Lumicon, but I hope whatever happens they're both able to stick around and maintain a trustworthy brand since I enjoy having both around.

 

Anyway, the only Lumicon brand filter I currently own is an old (probably early to mid 2000's) 2" SWAN band comet filter that I bought second hand. I wonder if they'd be willing to test that filter? Although the filter looks great and appears to have been very well kept, I'm wondering if the coatings have degraded over it's lifetime. 

 

Guess I'll give the link a try and see what happens. Thanks again for sharing!

[Polyphemos]

Oh wow, thanks for sharing this. There's been some rumors going around about Farpoint & Lumicon, but I hope whatever happens they're both able to stick around and maintain a trustworthy brand since I enjoy having both around.

 

Anyway, the only Lumicon brand filter I currently own is an old (probably early to mid 2000's) 2" SWAN band comet filter that I bought second hand. I wonder if they'd be willing to test that filter? Although the filter looks great and appears to have been very well kept, I'm wondering if the coatings have degraded over it's lifetime. 

 

Guess I'll give the link a try and see what happens. Thanks again for sharing!

Let us know what happens…

[vrodriguez2324]

Jim,

 

Did your filter have Gen 3 stamped on the aluminum ring?

 

-Victor

[Polyphemos]

Jim,

 

Did your filter have Gen 3 stamped on the aluminum ring?

 

-Victor

It did, which ring was apparently not sourced by SVOTek and who doesn’t recognize a Gen 3 filter.

 

I’m speculating here, but perhaps the Gen 3 moniker was a OSI/FarPoint invention that was to apply to future Lumicon branded filters sourced from manufacturers other than SVOTek. My SVOTek filter found its way into a Gen 3 ring; other non-SVOTek filters, possibly China sourced, did also. The only reliable way to tell which is which is to test.

[Starman1]

The Lumicon Gen.3 filters from OSI were US-made, but weren't from SVOTek, I was told.

OSI did sell a Chinese-made filter, notably in O-III, that was a poorly-made filter.

They were usually sold as economy O-III filters for less.  They were offered to dealers, but I never carried them.

If your O-III test is of one labeled as Gen.3 O-III, that represents a shady business practice.

 

My Gen.3 UHC closely matched yours.

My Gen.3 O-III, however, did not match yours.

Here were the lab-measured specs for my Gen 3 O-III from OSI about 2018 (measured from 200-1000nm, but I will only post 450-550nm for brevity):

450 0.166856988
451 0.04511126
452 0.091671433
453 0.045239825
454 0.047161055
455 0.061852673
456 0.120792064
457 0.038088541
458 0.042236005
459 0.040754012
460 0.043694774
461 0.04995855
462 0.047550753
463 0.085523134
464 0.047718796
465 0.033542408
466 0.16285695
467 0.093116483
468 0.131746925
469 0.060536024
470 0.183871512
471 0.058744556
472 0.063608471
473 0.053002003
474 0.055264219
475 0.052780515
476 0.052531971
477 0.0532998
478 0.058140617
479 0.048087437
480 0.203887474
481 0.054166324
482 0.105969949
483 0.048825243
484 0.043346622
485 0.034623656
486 0.035386543
487 0.042043255
488 0.12414747
489 0.112057728
490 0.14422576
491 0.236399599
492 1.503990663
493 14.07489389
494 57.14095801
495 86.59966509
496 95.18636733
497 95.04913935
498 92.6210316
499 93.06149545
500 95.32389809
501 94.70183924
502 93.13918286
503 90.77182536
504 89.41233137
505 78.4970101
506 37.64096125
507 11.15409477
508 1.657348186
509 0.882033571
510 0.283378455
511 0.225921299
512 0.325571006
513 0.264346461
514 0.161133465
515 0.682802768
516 0.150149264
517 0.132056845
518 0.386293076
519 0.280680747
520 0.247522006
521 0.151298743
522 0.24755163
523 0.165694426
524 0.154840365
525 0.077942301
526 0.081522911
527 0.070858485
528 0.144872815
529 0.12281085
530 0.187445831
531 0.15400601
532 0.064253474
533 0.202917119
534 0.070005146
535 0.128872246
536 0.074418225
537 0.149916172
538 0.060658711
539 0.060022966
540 0.110543286
541 0.130472662
542 0.053598505
543 0.068323022
544 0.052975415
545 0.216443384
546 0.163773058
547 0.061790904
548 0.054514459
549 0.064127247
550 0.070695217

 

FWHM from 494-505nm, about 11nm.

Transmission peak: 95.3% at 500nm.

495.9nm--94.3%

500.7nm--94.9%

 

I tested over 50 different filters that year, and the (then current) Lumicons were among them.

 

I'm glad SVOTek is offering filter testing.. It would seem wise that people who have Lumicon filters from the 2018-2022 era have their filters tested.

Edited by Starman1, 09 February 2024 - 11:02 AM.

[f18dad]

"The Lumicon Gen.3 filters from OSI were US-made, but weren't from SVOTek, I was told."

 

Quite a juicy revelation. The plot thickens. Wondering who that would be? 

 

Boy am I glad I went with Tele Vue (by Astronomik) at the time, with Tele Vue testing. This is "a riddle, wrapped in a mystery, inside an enigma."

Edited by f18dad, 09 February 2024 - 11:43 AM.

[peter k]

I bought one of the Limicon Gen. 3 O-III filters a few years ago, based partly on Uncle Rod’s effusive review in S&T. My impressions were similar to his—the Gen. 3 seemed to perform a bit better than my decades old Lumicon O-III. I think I may send it in for testing anyway. 

Edited by peter k, 09 February 2024 - 11:45 AM.

[MrJones]

 

FWHM from 494-505nm, about 11nm.

Transmission peak: 95.3% at 500nm.

495.9nm--94.3%

500.7nm--94.9%

 

I tested over 50 different filters that year, and the (then current) Lumicons were among them.

 

I'm glad SVOTek is offering filter testing.. It would seem wise that people who have Lumicon filters from the 2018-2022 era have their filters tested.

Thanks, I remember this post now. Here was my comment

 

https://www.cloudyni...-2#entry8728713

 

"these filters have an issue. The Lumicon scan from Doug is showing blocking of ~0.5% in the out-of-band areas?! The old Lumicon specs are standard OD4 spec out-of-band blocking, T < 0.01% at I think 440-475 nm and 520-630 nm, so not even close"

 

"This is maybe the worst blocking performance I've seen from a "premium" narrowband filter. As good blocking can cut transmission a little, one could speculate that the designer decided to compromise blocking to eek out a little more T but it could also be just to cut costs. Regardless this would be an automatic rejection with professional contract narrowband filters. Very disappointing"

 

As per my comment in the other thread also, does it really matter for visual? Maybe not much. I do still really like my Farpoint UHC filter but a shame about the rest of the mess.

 

And I agree that it's very nice SVOTek is testing filters for customers.

[Starman1]

I agree that a truly premium filter should have OOB transmission of <0.01% at any wavelength from 400-700nm.

I'm not sure many filters that are affordable would live up to that standard, however.

With scotopic vision sensitivity almost entirely in the 450-550nm range, hitting close to zero at 425nm and 600nm, what happens with wavelengths below and above those cutoffs

would seem to be unimportant visually, so if letting light through above and below makes a filter less expensive, it might be a good compromise.

My Lumicon 2010 UHC (Barr/Materion) performs very well, yet has significant OOB transmission.

Photographically, though, you'd want suppression of OOB wavelengths well into the IR.

 

Yeah, it's a shame about the rest of the story.

I tested a batch of UHC filters near the end of OSI's availability and the transmissions were all over the place, as were the bandwidths and bandwidth placements.

OSI denied that, of course.  Sad.

Edited by Starman1, 09 February 2024 - 01:33 PM.

[f18dad]

Now we are all taking out our flashlights to check the dust on our mirrors.

[MrJones]

The Lumicon Gen.3 filters from OSI were US-made, but weren't from SVOTek

One of these threads seems to keep disappearing hmm. I guess I thought all the Gen3 filters were made in house. Cary always said that was his goal and I remember he upgraded his deposition controller in 2019. Maybe that was just for OWL though.

Edited by MrJones, 15 February 2024 - 12:26 PM.

[sixela]

Since we're talking about Lumicon here is an independent test result of an "SVOTek" branded UHC (which SVOTek now also sells for slightly more as lumiconinc filters) from someone in Poland, with a comparison against a recent Astronomik (it was in the thread that keeps disappearing, but let's leave politics out of this one).



Discussion can be found at https://astropolis.p...#comment-848919 and https://astropolis.p...n-svotek-2-uhc/ (to cross-reference the filter test report that SVOTek included).

Searching for "Lumicon" in that thread will also reveal another graph with other 'Lumicon' filters, amongst others an OIII filter that seems to be very different.

Edited by sixela, 15 February 2024 - 01:24 PM.

[jeffmac]

I agree that a truly premium filter should have OOB transmission of <0.01% at any wavelength from 400-700nm.
I'm not sure many filters that are affordable would live up to that standard, however.
With scotopic vision sensitivity almost entirely in the 450-550nm range, hitting close to zero at 425nm and 600nm, what happens with wavelengths below and above those cutoffs
would seem to be unimportant visually, so if letting light through above and below makes a filter less expensive, it might be a good compromise.
My Lumicon 2010 UHC (Barr/Materion) performs very well, yet has significant OOB transmission.
Photographically, though, you'd want suppression of OOB wavelengths well into the IR.
 
Yeah, it's a shame about the rest of the story.
I tested a batch of UHC filters near the end of OSI's availability and the transmissions were all over the place, as were the bandwidths and bandwidth placements.
OSI denied that, of course.  Sad.

And to the point of Don having tested a batch of OSI Lumicon UHC filters, Lumicon filters, at one time, were individually tested with the results printed on the included filter case. At some point in time, the printed test results were changed to reflect an average transmission from batches of filters. The filters were no longer individually tested, IIRC, although some retailers maintained the "individually tested" description of Lumicon filters on their websites. This may have added to the confusion. That being said, while I have not had my GEN 3 UHC filter tested, it seems to yield excellent results in the field.

[RichA]

The Lumicon Gen.3 filters from OSI were US-made, but weren't from SVOTek, I was told.

OSI did sell a Chinese-made filter, notably in O-III, that was a poorly-made filter.

They were usually sold as economy O-III filters for less.  They were offered to dealers, but I never carried them.

If your O-III test is of one labeled as Gen.3 O-III, that represents a shady business practice.

 

My Gen.3 UHC closely matched yours.

My Gen.3 O-III, however, did not match yours.

Here were the lab-measured specs for my Gen 3 O-III from OSI about 2018 (measured from 200-1000nm, but I will only post 450-550nm for brevity):

450 0.166856988
…
550 0.070695217

 

FWHM from 494-505nm, about 11nm.

Transmission peak: 95.3% at 500nm.

495.9nm--94.3%

500.7nm--94.9%

 

I tested over 50 different filters that year, and the (then current) Lumicons were among them.

 

I'm glad SVOTek is offering filter testing.. It would seem wise that people who have Lumicon filters from the 2018-2022 era have their filters tested.

 

Why did I suspect Farpoint had left the business?  Something about it six months ago or so.

This reminds me of when a Quebec firm was selling fake Gillette razor blades.  Anything small, relatively simple will be copied (faked) by China and the products are almost always far worse in quality.  Nikon and Canon spend a lot of time warming people spending $3000 on cameras NOT to buy knock-off lithium batteries, etc.

[Universe XY]

I recently sent in my FarPoint purchased Lumicon UHC Gen 3 filter to Silicon Valley Optical Technology, Inc. (SVOTek) for spectrum analysis. I was concerned that FarPoint may have sourced my filter from China, and that it might not meet published specifications. The results are as follows:

 

IMG_2455.png
 

Test results were transmitted under this email from SVOTek:

 

IMG_2457.jpeg

 

And so it appears my filter was manufactured by SVOTek, and that it does meet specifications. Other filters sold by FarPoint under the Lumicon name did not meet specifications, like this Oiii filter for example:

 

IMG_2454.png

 

The particulars behind this filter were sent in an email to the owner, a part of which is as follows:

 

“After inspecting the filter you sent us:

 

1. We have replaced your ring with a brand new one, so your filter should be good to go. We will ship you the filter soon with a tracking number.

 

2. We would like to inquire: from which vendor did you purchase this filter from?

 

While repairing your filter, we noticed that the ring design did not match our own. Additionally, our engineers did a filter spectrum analysis and discovered that there is a discrepancy in the transmission graph. Per our website, the Lumicon O-III filter transmission should be > 90% from 496.5 nm - 501.5nm, with a peak at 498.5 += 2nm wavelength. However, this filter peaks at 492 nm which misses the spec by a significant 6 nm, something our strict qualify control would have caught far before it reached shipment. The filter has at best 10% effectiveness compared to its specs.

 

We are concerned that you may have been misled about the authenticity of this filter. There have been many counterfeit Lumicon products as of late, and we fear that their poor quality will tarnish the Lumicon brand and legacy.

 

Thank you,

Andrew
Lumicon Inc.”

 

If you have concerns about the authenticity of your own Lumicon filters, and particularly about those sold by FarPoint, SVOTek has offered to test Lumicon branded filters free of charge. I do not know how long this offer might stand, and you will need to provide a postage paid return label if you’d like your filter back after testing. You can find contact information for this service on the SVOTek website at:

 

http://www.svotek.com/
 

Good Luck!

Good call.  That's not good & glad SVO & Lumicon were responsive. We have to be aware that many of these not so good China may be roaming around in the used market.

 

I bought a used off the e pay...Lumicon Deep Sky LF 3010

 

 

 

 

Edited by Universe XY, 13 March 2025 - 08:19 PM.

[Starman1]

However, SVO Tek's 496.5-501.5 misses the 495.9nm O-III line. so it isn't a good one either.

That's what I found:  currently the best O-IIIs are the Astronomik and Tele Vue.

My Orion, DGM, and TO O-III filters did not test well.

My Lumicon O-III did, but it was the one sold as a Gen.3 and came from another US maker.

No O-III has beaten my 2018 Tele Vue O-III filter so far:

12nm bandwidth

H-ß 1.6%

O-III (line 1) 99.2%

O-III (line 2) 98.4%

H-α N/A 

FWHM at 492 504nm

Edited by Starman1, 13 March 2025 - 08:00 PM.

[f18dad]

Don, you say your DGM did not test well, but does it function well for your visual observing purposes?

 

Or are you talking about the DGM O-III only?

Edited by f18dad, 13 March 2025 - 08:17 PM.

[Starman1]

Don, you say your DGM did not test well, but does it function well for your visual observing purposes?

Or are you talking about the DGM O-III only?

I was talking only about O-III filters. The NPB is superb.

[sanbai]

I bought from Don an OIII-Gen3 from "lumicon-farpoint" in 09/2019. I tested it with a spectrometer at my previous workplace, and it was in-spec. I posted about it.
I believe I also tested a UHC-GenIII "lumicon-farpoint", which I bought also from Don in 09/2020. I think the test was good, but I don't have records and my memory fails . Probably it was indeed good and I just moved forward happily (the computer for that instrument was not record-keeping-friendly...).

I also have a "lumicon-Farpoint" comet filter, which I bought on 09/2023 directly from Farpoint Astro not long before they went downhill. I had not very good expectations (for the type of filter, not about quality), but the 50% discount was attractive enough to give it a try. It has been, indeed, disappointing. Given the nature of the what it filters, probably the fault is at the (few) opportunities/conditions I had, rather the the filter itself. I had not tested it in the spectrometer (too late now).

 

I had to buy a new nebula filter now, I would indeed go Astronomiks/Televue. I actually got the Televue H-beta Bandmate-II back when I got the "UHC-Gen3".