Hi from Massachusetts

[Toby]

Hi my name is Tobias but I'll be going by Toby on here.

 

I am an electrical and computer engineering student in Massachusetts. For my photography capstone project I'm doing an exploration of photography using non visible light. So far I've experimented with NIR and UVIVF methods (links are to albums of my experiments).

 

For Infrared I modified a Canon 60D to shoot full spectrum and have been using K720 and K590 filters.

 

For UVIVF I have been using a Sony a7iii and two convoy S2+ torches with a ZWB2 filter taped over them. This has given me ok results but I'm still suffering from significant blue contamination. From my research it seems like switching to a legit 2mm UG-1 or UG-11 (or possibly a U-340) should help fix the problem (I don't think I need a S8612 since the sources shouldn't produce significant IR). I also have not been using a filter over the camera lens to cut UV/IR since I think the hot mirror does a good enough job at that.

 

Input on my setups would be greatly appreciated.

 

Thanks!

I look forward to learning a lot more about this interesting field of photography.

[nfoto]

Welcome to UVP. You do bring interesting expertise to our community

 

As to the UVIVF setup, do you shoot in a total dark room? I'm asking because your camera would respond to any visible light otherwise.

[Toby]

Welcome to UVP. You do bring interesting expertise to our community

 

As to the UVIVF setup, do you shoot in a total dark room? I'm asking because your camera would respond to any visible light otherwise.

 

Yes! I do shoot in a totally dark room (or as dark as I can get it). Though I'm planning on branching out and attempting UVIVF in situ imaging, which may require switching from torches to a flash.

[nfoto]

Dirt, lint or fatty residues tend to come out blue in UVIVF ....

 

One sometimes gets a nasty surprise when doing UV fluorescence stuff in kitchen or bathrooms

[dabateman]

Welcome,

Yes its pricey compared to dirt cheap Zwb2, but 2mm U340 20.5mm filters are the best for your convoy. That will ensure you only have UV light directed at your subject.

 

If you go flash that can be tricky. You can either buy the expensive S8612/U340 set for a Canon 199A flash. Or mke a modified 52mm holder for your flash and buy 52mm filters which you may end up using anyway in the future with your camera.

 

For my UVIVF, I use 365nm led E26 bulbs that you can buy from Amazon. I cut the plastic dome off and tape a 55mm to 52mm step down ring on them. Then filter for UV only light.

Then I use either a Tiffen 2A and S8612 filter on the camera. Or a UV/IR cut filter on the camera. The BW 486 cut isn't great. They now let in 380 to 730nm light through. I have older Sigma SD15 UV/IR blocking filters that I adapted to a 52mm ring. They are 410nm to 680nm hard cut if I remembered correctly.

 

Have fun and there are many people here to help. Andy is also in Massachusetts, I think.

[Andy Perrin]

Dirt, lint or fatty residues tend to come out blue in UVIVF ....

 

One sometimes gets a nasty surprise when doing UV fluorescence stuff in kitchen or bathrooms

To me it confirms the essential uselessness of trying to get things "clean". At best one can get rid of the obvious blemishes, so that visitors don't object. Anything more is wasted effort.

 

And yes, I'm in Mass.

[Akira]

Welcome, Toby!

 

I have no experience with U-340, but, judging from my sad experience with U-330, you may want to avoid U-340. My U-330 was deteriorated by the moisture a while after I had purchased it. According to the data sheets published by Hoya, the Dw index of U-340 is the same as that of U-330 (which is "4"). So, U-340 would be as prone to be deteriorated as U-330. The Dw index of my U-360 is "3" (the lower, the better), and it has been pristine since I had purchased it more than 10 years ago.

 

Schott UG-11 shows the very similar optical characteristics as U-340, so I would fear that it is similarly destined. The Baader Venus-U uses UG-11, but the multiple coating protects the glass.

[colinbm]

Akira, you can use regular Hydrogen Peroxide, which is usually 3% general consumer grade, to clean the damaged filters.

Toby, welcome to the invisible world.

[Toby]

Thanks all for your advice!

 

I think I'll be moving forward by buying a couple 20.5mm U-340 inserts for my Convoys. While this gives me less flexibility in the long run, by making it impossible to use the same filters on a lens or flash, the convenience of having self contained independent sources is a major factor. Also I'm able to get a few hundred dollars of funding through my school for this project so I don't need to be as stingy as I usually am.

[colinbm]

Toby, there is nothing stingy about UV photography....Ha Ha

[Andy Perrin]

Yeah...despite our best efforts to contain costs, this is not a cheap hobby. Especially if you expand your scope to include even the shorter end of the UV-A wavelengths.

[dabateman]

Thanks all for your advice!

 

I think I'll be moving forward by buying a couple 20.5mm U-340 inserts for my Convoys. While this gives me less flexibility in the long run, by making it impossible to use the same filters on a lens or flash, the convenience of having self contained independent sources is a major factor. Also I'm able to get a few hundred dollars of funding through my school for this project so I don't need to be as stingy as I usually am.

 

Actually no!

I ordered 2 for my convoys. But one of my convoys ended up not working correctly. So I was able to carefully mount the U340 filter into a 25mm filter ring. The Chinese 25mm filters, hole is 20mm. So it just covers it. You have to be really careful placing the retaining ring back on.

A 25mm filter, can be used if you go the micro four thirds camera route with Olympus, which have weak UV blocking or Panasonic cameras. I never tested a YiM1 camera, but they are really cheap with the good Sony 20Mpixel sensor.

Most UV capable lense have small front elements or rear. So 25mm filters with 20mm opening does not impact the image. You can also stack filters if you reverse mount but can't easily change them.

This filter size also works for the cheapest quartz lens I know of, but don't own. The UV2528B 25mm f2.8 c-mout lens.

[colinbm]

Dave, these https://www.universeoptics.com/ quartz lenses, do they have a focusing ring & what are the focus range please ?

[dabateman]

Colin this is the link to the UKA 25mm lens.

https://www.universeoptics.com/product/uv2528b-ultraviolet-quartz-lens-assemblies/

 

You can download the data sheet. Yes this one has a focus ring and aperture ring (the B in name means it has aperture ring).

I don't own it but there are some comments here about it here:

https://www.ultravioletphotography.com/content/index.php/topic/986-cctv-lens-for-uv/page__view__findpost__p__4127

[Akira]

Akira, you can use regular Hydrogen Peroxide, which is usually 3% general consumer grade, to clean the damaged filters.

 

Colin, thank you for the tip!

[Andrea B.]

Hello Toby and Welcome to UVP!

I am somewhat late in getting around to the Intro section. I plead distraction due to politics and pandemics!

 

For my photography capstone project I'm doing an exploration of photography using non visible light.

 

I hope your project is going well (has gone well?). Please let us know if we can help in any way.