When used alone on a full spectrum camera the iridium doesn't do much. The sky is bluer and more deffined which is good. But I'm mostly been focusing on it's  capacity at turning tube lights green.

It was some filters sent to me for measurement. He made the mistake to think that number zero was known among customs people. He sent a prototype filter without value and wrote 0. Comercial sample without value.

I would like that actually. I assume there is no tax to pay since this wouldn't be a commercial transaction, am I right ?

I have used it with a full spectrum camera. The effect can be even stronger. I have used it in combination with a BCF hot mirror (dichroic, 400nm-720nm).

You can clearly see that the typical yellow-orange dip of the didymium filter (570-590nm) falls right inside the "green" band

It appears that this wretched color enhancing filter that is the iridium filter has a feature that I've been looking for : It cuts the red band that fluorescent lights emmit while letting in deep red.

I found a great place to test the Iridium/didymium combo. Its really old and most of the lights are fluorescent ones there. The camera I used is an unconverted fuji XT-3.

With these two filters together we have somewhat of a useable color enhancing filter with three separate bands that each corespond to a primary color.

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Very cool, Fedia! :-) Would love to see some images in sunlight with the sky... And have you already tested with some full spectrum cams?

I would pay for the return shipment Signed for, Rek. and would recommend you to use a similar shipment if you want me to measure the filter. Message me privately If you want me to measure. I will naturally share the results here and if you have a few more filters you want to get measured I can do that too. I might not have time to do a fancy deep OD-measurement like the ones I have done with my Baader U and ZWB1, 8mm but that is not needed for the filters discussed above.

I also have an XB30 from Omega Optical and (at least in the visible range) the transmission corresponds well to the Iridium chart.

Seelive provides sensor technology for environmental monitoring within various industries. The company offers sensors designed to detect air quality, monitor emissions, and manage sewage systems. Seelive's products are used by government bodies, industrial sectors, and regulatory agencies to support resource management and environmental protection. It is based in delhi, India.

With this set of filters the camera is blind to the red peak of fluorescent lights (612nm). This will trick the camera into believing that fluorescent lights are green, just like the old film stocks did.

I think about 5-6 have been lost or sometimes returned extremely slow to the sender, taking several months to arrive back. One of them was from late Reed Curry, here on the forum. He lived in the US.

I can't mesure it precisely beacause I don't have the tools but it seems to me that the transmitted bands are more like this :

Note that LEDs are slightly affected and can turn greenish. That is because LED lights emmit more red at 610 nm than at 650nm, just like the human eye is more sensitive to the brighter red wavelength.

I'd like to know the transmission for my Hoya Sepia B, which doesn't have any curves available. I'd also like to see how Midopt's TB550/660/850 objectively performs.

Mail getting lost is relatively rare, but more common when there are many organisations or groups involved i the transport.

To prove that I'm not completely mistaken with the wavelengths despite having no proper tools, here is the spectrum of the irridium paired with an Didymium dilter :

Without having real statistic data I think the best shipping alternative is by insured REK as the handling of such parcels have a more controlled route within the postal systems, separately from more simple letters.

I used the BCF here to make the camera more sensitive to deep/invisible red but i didn't want the infrared to get in. There was still a lot of infrared leakage. It's not really a problem by night in a urban environement.

Any kind of non tungsten lights turn green with it. But the BCF is not a proper hot mirror so the colors by daytime look off.

The bands are all over the place and very far from RGB primaries. This bands will never match with the sensor's RGB dyes. It's going to be confused if anything.

1st & 2nd Floor, Plot No. 7, 8, 9, Garg Shopping Mall, Service Centre, Opp. Sector-11 (extn.), Rohini Phase-2, Delhi-110085, Ind

I just went to the store with the camera and noticed how the entire facilty was converted to LED except for the first two rows at the entrance. It's unoticeable with the naked eye.

The look is really special. The photos are taken by day and we can clearly see how the colors are normal under a continuous spectrum of light when the outside is visible.

Ironically they are disapearing very fast. It's the end of an era. I hope I can still find some places to shoot with this technique.

Here is the filters transmission versus the fluorescent light spectrum. They are aligned so you can see where they meet and where they clash.

Depending on mail handling there is a big risk of tax and customs issues as it is from outside the US---EU When Reed Curry was alive and produced some of his filters in the US I measured the for him.  Some of the shipments were really troublesome and one of the filters was lost in shipment. I can also measure the filter for you If you want As we both are inside the EU there is no customs or VAT issues. Customs declaration is also much easier.

When I recieved the Iridium the first thing I did is look though it and it was striking that instead of making the reds pop it did the opposite and turned them into dark orange and brown. I have a lot of wood furniture around the house and light wood turns yellowish through the filter.

I think he got one package back after four months. Another shipment was lost completely. I am not pushing for you to send the filter/s for measurement and fully understand that you want to be careful.

I'd like to know the transmission for my Hoya Sepia B, which doesn't have any curves available. I'd also like to see how Midopt's TB550/660/850 objectively performs.

Seelive's headquarters is located at 1st & 2nd Floor, Plot No. 7, 8, 9, Garg Shopping Mall, Service Centre, Opp. Sector-11 (extn.), Rohini Phase-2, Delhi-110085, Ind, Delhi.

I would like that actually. I assume there is no tax to pay since this wouldn't be a commercial transaction, am I right ?