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UltravioletPhotography

Hi all and thank you for accepting me into your photography community


Liberty Gray

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Hi everyone,

 

I thought I would introduce myself... I'm a recent graduate of Zoology BSc at the University of Lincoln (UK) and am now currently studying for my masters by research. My project is focused on whether UVB radiation is a driver of UV floral patterning, and to what extent this is evolutionary change or plastic change. I'm very lucky in that I've been granted access to some very large museums and herbariums and will be permitted to take some photographs of pressed flower specimens (some from the 1800s!). I'll also be taking some photographs of live flowers in-field and within some laboratory experiments I'll be doing. There is a small amount of literature on this area of research thatI personally find very exciting so if anybody would like some pdfs of previous studies let me know...I would provide tthe links but these are often inaccessible without purchasing.

I'll be very honest - I have no photography skills, and I'm not massively confident handling a camera...I feel somewhat overwhelmed by the amount of things I feel I need to learn to become competent at UV photography. I have also have a very small vocabulary of photography terminology...so learning via online tutorials and posts has been a little challenging! I am however not one to be defeated so early on, and can always count on my determination to get a handle on something that's challenging me. I have taken some photographs of flowers in natural light in the garden of my flat with reasonable success (I have been given a Canon EOS 400D, a ring that screws onto the lens and holds a Baader UBVRI Photometric U-Filter 1/4"), however when I take the photography indoors, much of what I capture is a completely black image! I suspect I don't have enough light? This worries me as much of what I'll be hoping to photograph exists indoors within the herbariums and museums, and I can't guarantee a good light source in the places I'll be allowed to work. Having looked at the literature I can see so many sources of light that I could choose from, some that you just purchase and switch on, and others that require some tinkering about with and DIY to convert. I would be so grateful if anybody here has any suggestions on what I could do, as a student I have limited resources, but if something is reasonably affordable I could perhaps request that my supervisor order something in. That would be the hope!

Thanks in advance for reading my very long post, and I hope someday to be in a position to impart knowledge regarding UV photography!

 

Liberty

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Welcome to the Forum, Liberty. There's plenty of people here who can help with advice so you've come to the right place. UV imaging does have its 'quirks'.

 

Let's start at the beginning. When you say you've been given a 400D, is that one that has been modified for UV imaging (has it been converted for UV by someone)?

 

Next thing is lens - what is it you're using? Not all lenses let through UV, so you'll need the right lens. Thankfully there are quite a few which will let through enough UV for use with a converted camera.

 

Something to keep in mind. With a normal (modified) SLR camera you'll be imaging what things look like in UVA not UVB - they are not sensitive enough down in UVB, and if you were to try and go down that route, you'll definitely need a dedicated UV lens and specialist camera.

 

Jonathan

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Hi Liberty, welcome to UVP :)

 

Baader UBVRI Photometric U-Filter 1/4"

post-136-0-66340700-1516206715.jpg

 

This flter pass light between 320nm and 420nm, therefore it is unsuitable for UV-B photography which ranges from315 to 280nm. Moreover it would not be suitable for "true" UV-A photography since it leaks some violet light.

 

For imaging in UV-B you would need:

  • A filter that pass light from 280 to 315nm only. I know there is a 295nm available out there, I think Andrea has one.
  • A specialized lens (often made out of quartz or calcium fluoride) that can let those short wavelenghts pass through it. Most ordinary lenses available on the market block all wavelenghts shorter than ~390nm. Even the the EL-Nikkor 80mm wich is the best non-dedicated UV capable lens is completely blind past 325nm.
  • A specialized camera. Most camera, even modified, hardly record anything around 300nm.
  • A light source that emits a copious amount of UV-B. I think a modified flash could do the job fine.
  • And for last, good eye and skin protections!

This will be expensive. A filter generaly costs $$$, the camera would costs $$$-$$$$ and the lens will cost $$$$. Not to discourage you but this is the principal reason why we all stick to UV-A photography.

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Klaus Schmidt seems to know the most about UVB imaging (of people I am familiar with). It is going to be a VERY expensive endeavor! You can speak with him via his facebook. He may be able to advise on the specifics.
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I am not aware of any pollinators that see significantly into the UV-B, so while your investigation of UV-B influence on floral patterning may in some way need to account for variances in environmental UV-B, reflected UV-A will likely suffice in your imaging efforts.
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Probably the camera sensor will limit you to a sliver of UV-B from about 300nm to 320nm, you will need a ~$5,000 UV-Nikkor to start with, and a filter that will concentrate on that range,

because UV-A mixed in will probably overpower it, like trying to shoot a UV-A photo using a BG40 alone (even though BG40 is UV-A + Visual, you will not see the UV, just the visual).

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What Cadmium meant was isolating and recording [a sliver of] UV-B implies using an efficient UV bandpass filter allowing only that range and a very expensive lens like a UV-Nikkor. (not to mention having a camera capable of capturing UV-B ). Then, there is the question of getting adequate UV-B illumination to allow any photographic record at all. Not an easy task.

 

Getting a helpful UV-A capture can be done with very simple means. A stock Nikon D40/D70 (even better with a modified camera) and a decent UV-capable lens, plus a Baader-U and a UV-enriched flash should suffice most purposes.

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Hello Liberty and welcome to UVP.

 

To get a good introduction to reflected UV photography, you might like to consult our "Stickies" in the Reference section.

 

Sticky :: UV Photography: Cams, Mods, Lights, Links

Sticky :: UV-Capable Lenses

Sticky :: UV/Vis/IR Filters

 


 

I see that Bjørn and our members have already pointed you in the direction you would need to go in order to accomplish photography in the UV-B range. I am sorry to say that your project is not feasible with the typical UV photography equipment we use for UV-A photography, so you should consult with your academic committee about this. Are you sure it is UV-B you want to work on?

 

The primary point to understand is that UV-B radiation is in the 280-315 nm range and requires specialized gear for reflected UV-B photography. I think that Hornblende's post above has summarized it very well. To repeat (with additions), you will need the following --

 

Filter which passes UV-B light (only): Such filters can be purchased from an optical filters manufacturer. I would suggest a filter centered around a peak of 300nm.

Link to Omega Optical's UV-pass filter page: http://www.omegafilters.com/products/filters.html?search_cwl_string=254

 

Camera which can image UV-B: You will need a specialized "industrial" CCD camera rather than a Canon DSLR which cannot image in the UV-B range. I do not have any recommended suppliers for such a camera.

 

Lens which passes UV-B light: There are 2 possibilities for this -- either an industrial UV lens or the Rayfact 105mm f/4.5 lens made by Nikon's Tochigi subsidiary. Any such lens will be in the price range from (US)$3000-$7000 = (UK)£2165-£5050.

Link for Rayfact lens: http://www.company7.com/nikon/lens/0105f4.5uv.html

Link for Universe industrial UV lens: http://www.universeoptics.com/uvlens_assemblies/

 

Source of UV-B illumination: Natural sunlight has only about 3% UV with the rest being in the Visible and Infrared range. Of that small amount of UV in sunlight there is very little UV-B. So you will need some kind of UV-B lamp to assist in making UVB photos.

 

Our founder, Bjørn Rørslett, has a PhD in aquatic botany as well as being a professional photographer. So you and your academic advisor might want to consult him further about the design of your Master's degree project to ensure its feasibility? You can contact Bjørn privately using our PM system. Click your name in the upper right-hand corner and choose Personal Messenger from the drop-down menu.

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(The above is what’s necessary for scientific quality images. I have been considering a much cheaper setup with a fluorescent screen and a relay lens like my SWIR setup but it would have similar limitations concerning really grainy image quality.)
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