Hi all,

has anyone built a DIY fluorescence filter? I've almost no experience with (underwater) fluorescence photography, what I've tried is blue filter gel taped over the strobes - did work, but not great.

With 3D printing, it should be easy to build a mount for the strobes, but what I'm missing is the right blue filter. I've found blue acrylic sheets (3mm thick), but those aren't really optimized for fluorescence.

Any idea where to source the right material with a diameter of ~95mm?

Thanks!

Best bet is

https://firedivegear.com/product-category/underwater-excitation-filters/?srsltid=AfmBOoq2VLqnwIP-w6R4v6TwUzK5REVPVIyEsSat8Oty7SOH245XDsQ2

they have all kinds of excitation filters. Cheap ones won't work.

BvA

3 hours ago, bvanant said:

Best bet is

https://firedivegear.com/product-category/underwater-excitation-filters/?srsltid=AfmBOoq2VLqnwIP-w6R4v6TwUzK5REVPVIyEsSat8Oty7SOH245XDsQ2

they have all kinds of excitation filters. Cheap ones won't work.

BvA

had a look at the website and there is a suspicious verify you are human page that comes up asking to open a run dialog box and paste in a command the site placed into the clipboard. seems like this is malware of some sort. Needless to say I didn't run the command as asked.

5 hours ago, Chris Ross said:

had a look at the website and there is a suspicious verify you are human page that comes up asking to open a run dialog box and paste in a command the site placed into the clipboard. seems like this is malware of some sort. Needless to say I didn't run the command as asked.

I didn't get it. It didn't show me the classic privacy banner either.

3 hours ago, Davide DB said:

I didn't get it. It didn't show me the classic privacy banner either.

It comes up after you click around a few different links, not straight away, I just tried again and it seems to come up when I click on the generic excitation filters box. this is what I get:

OUCH THAT IS A MALWARE FOR SURE!

Hmm. I tried my best to trigger the apparent malware but didn't succeed. Who knows what the difference is.

I was looking at the gallery, and I guess it's natural for people selling fluo gear, but I did think that the the fluo effect was a bit overused. For some of the subjects where I was familiar with them (e.g. mantis shrimp), I think a reasonable standard spectrum strobe setup would be superior. Of course that is utterly subjective, and someone more experienced than me might be bored of the subjects I still find interesting with standard spectrum.

The website works good on my end.

My luggage during my last flight was pretty compressed and I broke the pair of exciter filters I had (Ikelite ones). They are made of a dark blue plastic filter and a dichroic filter made of glass which is expensive and fragile. I haven't found a cheap source for dichroic filters. On the camera end, you need a yellow filter like the Tiffen Yellow 12 to remove the blue cast from the filter or blue/uv lights.

1 hour ago, Chris Ross said:

It comes up after you click around a few different links, not straight away, I just tried again and it seems to come up when I click on the generic excitation filters box. this is what I get:

But it says it's safe and supported by Windows 😂

1 hour ago, Yorkie88 said:

But it says it's safe and supported by Windows 😂

😂, looking around a bit some sites suggested it might get onto websites through ads- anyway just be careful, I would guess the site is fine as long as you don't follow the instructions.

On 9/12/2025 at 11:19 AM, Chris Ross said:

It comes up after you click around a few different links, not straight away, I just tried again and it seems to come up when I click on the generic excitation filters box. this is what I get:

Cloudflare thing is nothing unusual, a lot of websites use that to filter out bot traffic. Sometimes this triggers when you click too fast ;]

Windows dunno, I am not using Defender (SEP here), hence never seen it.

As for the filters +1 for what @bvanant said - I have tried multiple "cheap" ones, complete waste of money. But the ones from firedivegear deliver. And get TIffen 12 or BW (if only I could remember the number) filters for camera - one is more greenish one does excite more orange, like stone fish. Blue light matters as well. It is all about the wavelength baby.

I can recommend checking out Horst Grunz website:

https://www.uni-due.de/members/grunz/

Also attached is a PDF of various filters testing he did.

FluoreszenzFilterFinalUSApdf.pdf

Edited September 13, 2025Sep 13 by makar0n

Nothing weird on my end. A lot depends on what you want. The goal for classical fluorescence spectroscopy is to have no overlap between the excitation and emission spectra. Dichroic filters are what we use in the lab, cheap plastic blue PVC might work but you will miss a bunch of emission stuff that is close to the excitation spectrum. You can get dichroic filters from all kinds of science places like Thorlabs, Edmund, etc. but they get more expensive the bigger they are.

Bill