Jump to content
UltravioletPhotography

Ultraviolet dilemma


Vagabond

Recommended Posts

Hello everyone!

 

I hope I'm posting this in the correct thread, if it isn't I apologize beforehand :-)

 

I'm currently trying to gather some UV equipment to do herpetological research mainly in a laboratory setup (standardized) and I would borrow your experience to solve a couple of dilemmas:

So, far I could get "almost" for free an old 50mm Nikon E series which transmits nicely in the UV (tested with a borrowed Nikon D70).

 

I went to the local photography store looking for possible modifiable cameras to couple with the lens and the owner proposed 3 models: Nikon D7000 (used), Nikon D5200 (used), Nikon D3400 (new).

The info that I could gather here seems to point to the D7000:

D5200 may suffer from some kind of leakage in the IR: http://www.ultraviol...-light-leakage/

D3400 I simply could not find info on the forum, though the 3200 seems to be ok.

D7000 is the only one that has been tested (it seems): http://www.ultraviol...e-the-stickies/

 

As the purchase will be an important one, I don't want to make mistakes and ask first for your opinion.

 

I also take this opportunity to ask some infos about lighting: I admit I have been a bit lazy on this and didn't browse all the available pieces of information here, but on the other hand I'm also limited by the importation policies and the budget to choose studio lamps here (I'm in Argentina).

So far, I used a separate source of light for visible range and a borrowed UV-A tube, which is technically not the best option, especially because the UV source did not create diffuse light and it was more imprecise as I had to hold it with my hands.

 

The only readily available lamp on the market here seems to be this one: http://www.osram.com...talux/index.jsp

which sounds good as it simulates sunlight, though on the other hand it seems to project a pretty straight ray of light creating hard light which may be difficult to soften.

 

These are the other models available from the company which does not add import fees on its products: http://www.osram.com...lamps/index.jsp

 

I thank you very much for every input you'll be willing to provide!!!

 

Nicola

Link to comment
enricosavazzi

High-pressure xenon-arc lamps generally provide a higher ratio of UV-to-VIS than other types like halogen. Xenon-arc lamps are also more expensive, have a limited lifetime, and require a special power supply. As a whole, if you need a continuous source of high-intensity UV (tens of W or higher), there is no simple and cheap solution. If you need lots of UV without so much VIS, IR and heat, prices go up even more.

 

About the Osram lamp at your first link, it is probably one of the cheapest solutions, and from what I can see it does not require a special starter or power supply (but I might be wrong, so check with the seller). 16.6 W of total radiated UV is quite a lot for imaging at close range, and more than you can get with LEDs or fluorescent tubes. The remaining about 280 W of VIS and IR are going to cause a lot of heating of the subject, though, and would be very expensive to filter out before reaching the subject.

 

UV LEDs are relatively affordable today if you can do with about 1 W or less of radiated UV. However, they are narrow-band emitters usually centered around 365 nm. Mercury arc lamps also emit mostly at 365 nm (and a few other lines, mostly in the UV).

 

Are you sure you don't want to/cannot use a UV-enabled electronic flash instead of a continuous source? Electronic flash can ideally provide enough UV in a broad spectrum (200-400 nm wih a quartz tube or 300-400 nm with a pyrex tube, although the spectrum is not as uniform as a deuterium lamp) for imaging while avoiding most of the heating problems. If your subjects can be damaged by flash-heating or startled/damaged by the VIS emission of the flash, however, this may not be a good alternative.

 

Before operating any UV source, make sure you understand the risks of exposure of the subject and of the photographer to the chosen source (some are more dangerous than others, although none are completely safe), and take precautions accordingly.

Link to comment

I think a UV-flash or big UV-Led torch is probably the way to go. If you are going to attempt to photograph "in the field" you won't want to be dragging around an Osram lamp and heavy battery pack. Please do work through our UV Lighting search tag and check out the various items our members use for UV lighting.

Look on UVP member Enrico Savazzi's website for flash info: http://www.savazzi.n...phy/default.htm

Check with UVP member Shane Elen about importing one of his filtered flash conversions: http://www.beyondvis...BV4-UVSB14.html

Our sticky has some UV-Led listings (scroll way down): Sticky :: UV Photography Intro, Cams, Mods, Lights, Links

 

In your work, you must already have learned some info about how much UV the herps can tolerate and in what concentration in milliWatts per square centimeter of herp skin. But be aware that UV-flashes or UV-LED torches output a very concentrated amount of UV. So you need to compare the output from the UV illumination to the herp tolerance to make sure that one or two concentrated flashes won't harm them. For indoor work with herps in a cage or herpetarium, their existing reptile lamp may be sufficient for good photos? (You probably already know this.)

 

**********

 

For a UV camera, you need one with a very good high ISO capability so that exposure times (and flash times) can be kept as short as possible. And Live View is very very nice to have in UV/IR work. You also need to have an idea before camera purchase about what lens you might be using because each camera brand has a different requirement about the distance between sensor plate and lens end. This is called the flange focal distance or register distance. There are is a small variety of Nikon lenses (in our lens sticky) which could be used for your work. Look at the EL-Nikkor enlarging lens series for example. In order to make a more specific recommendation we would have to know the UV range in which you need to photograph. If it is from, say, 360-400nm, then there are many choices. If you need below 360nm, then your options begin to narrow unless you go for a dedicated (expensive) UV lens.

 

But back to the camera ---- For Nikon you also need to make sure your Nikon camera choice can handle one of the older manual lenses like the E you have already used or the EL-Nikkors I mentioned. Some newer Nikon cameras might not be as easily used with old manual lenses.

 

The Nikon D7000 you mention should be good. Also look for a used D610 because it makes a very good conversion for UV or IR. Both the D7000 and the D600 or D610 have Live View and very nice high ISO capabilities. I used the D600 for years as a full spectrum camera but it suffered from oil spots on the sensor. Nikon repaired a lot of those. So you could look for a used D600 which has been repaired.

 

However, there are also wise choices in the Sony brand for full spectrum conversions. And a Sony conversion would permit a wider choice of old UV capable lenses because it has a short flange focal distance in comparison to Nikon's rather long one. Using a Sony would require purchase of a mount adapter to fit between the Sony and any non-Sony lens, but mount adapters are relative inexpensive. Many members here use Sony conversions. Look for an older used Sony Alpha like the Sony NEX-6 or NEX-7, for example.

 

And you can put a Nikon lens on a Canon camera using a mount adapter. So don't rule out a Canon conversion. I don't know Canon well enough to mention a specific choice, but you can find some in by working through the UV Camera search tag. They tend to have more noise at high ISO settings, so Canon is a good but not great conversion. Canon has a fairly long FFD, so lens choice is more limited.

 

Used Panasonic Lumix cameras are easy to find and make good, but not great conversions. They are easy to use but are not quite as good at high ISO settings. You would need a mount adapter for any Lumix if using a non-Panasonic lens but Lumix has a short FFD so you get a wider lens choice in the old manual lens area.

 

There is also the Olympus cameras, good but not great conversions. Again needing a mount adapter for any non-Olympus lens. Again with a short FFD.

 

Even though for Canon/Lumix/Olympus you get more noise at high ISO settings, don't necessarily rule them out just because I said "good but not great" conversion. With good illumination, noise can be reduced. And I've seen some superb photography from some highly talented UV photographers with these cameras.

 

This is a lot to work through!

I'll try to get someone in to comment on the D7000 and the D5000 line of Nikons.

Link to comment
Bill De Jager
The Canon 6D (Mark I) has a reputation for low noise and has long been favored by astrophotographers for that reason. This assessment seems to be borne out by tests at dpreview.com: https://www.dpreview...ws/canon-eos-6d . I actually have one converted to broadband. Unfortunately, I set it aside due to other projects and haven't really tested it out yet.
Link to comment
Thanks, Bill. I am so unfamiliar with Canons. By what I call "historical accident", we usually wind up with a particular brand and stick to it. For me it was Nikon. But I certainly support any brand which can get the job done. :D
Link to comment

I have a full spectrum D7000 (converted by LifePixel), and I use it mostly. I like it very much, and it has a few features that make things work better than my older D90-UV/IR.

I also have a D7200 UV/IR, but frankly I just don't like it as much as the D7000.

Link to comment

I will second Enrico's suggestion to try an unfiltered Xe strobe. There have been many discussed on this forum.

 

I recommend the old Canon Speedlite 199A. It is very affordable on eBay and much safer to modify and seems to work well.

 

Also a strong UV LED is quite useful as a focusing aid. The Convoy 365nm LED flashlight (torch) is very affordable and quite powerful.

You can filter it to remove traces of visible for UV induced Fluorescence photographs.

Link to comment

Wow, first of all, thanks everyone for taking some time to answer me!!

 

I feel like I didn't provide enough context in my first post:

my ultimate aim with the photographs would be to convert them to cone catch quanta using the fantastic ImageJ plugin devised by Dr. Julian Troscianko.

 

Here's the link to the webpage, the videoguide posted at the bottom is great: http://www.jolyon.co...analysis-tools/

 

To use this tool, the photographs should fulfill a number of requisites, among these the two hardest in my case would be: get perfectly overlapping UV/VIS pictures, which seems fairly easy with shells, but it is not so easy with live lizards, especially because with the D70 and the not-so-strong UV lamp I was using it took me 15" to take a UV picture. Second thing would be to standardize the source of light for UV/VIS, I used two different sources of light (UV-tube and visible-range lamp) while Dr. Troscianko used a modified Iwasaki eyecolor arc-lamp which (if i remember correctly) closely mimics the sunlight spectra and additionally provides a nice diffuse light.

 

Hope this shed some light and sorry for not explain this earlier.

 

On to your suggestions:

 

-Camera: The final choice is the D7000, thank you for your inputs Andrea, Cadmium and Bill!

Though I am a Canon user in my freetime and the perspective of using a Canon for UV intrigues me , currently the Nikon D7000 fits best my needs.

 

-Source of light:

Thank you everyone for your comments, Enrico's and JCDowdy suggestions of using a modified flash sounds interesting, considering also that a fellow researcher may be in possession of a Vivitar 285 (though I don't know if he's ready to part from it for science sake!). I had a look at Shane Elen's page and it seems fairly easy to modify, though I'm still eligible for the Darwin award in this case, so I will be paying attention if we'll decide to modify it (I will go through all the info available on the vivitar in the forum).

A quick note: my lizards' peak UV reflectance lies at 377 nm, so 365 nm flashes/lamps should be ok?

 

Answering Andrea's comment, I don't know the UV-skin sensibility of my species (we don't currently own a solarmeter), if I will modify the Vivitar I'll be sure to test first its power and at least the moulted skin of my lizard (as they did at this link http://www.uvguide.co.uk/skintests.htm).

And the UV tubes we use do have quite a "spiky" spectra in the visible range (particularly in the blue range) so I was not planning to use them (also because they are long and a bit impractical for my lab setup), but in my free time I will try to see if i can find a holder for the tube and take a couple of pictures.

 

In the meanwhile I'll try to see how the Osram lamp behaves (and I'll be paying attention not to put it too close to the subjects, I don't want to fry them) and will look into Enrico's suggestion for a xenon-arc lamp, which looks rather nice, and see if it's readily available!

 

I thank you very very much for your useful inputs!

 

Cheers,

 

Nicola

Link to comment

You are very welcome!

Best of luck with your endeavor. Let us know how it is progressing when you get time to post.

Link to comment
  • 3 weeks later...

Hello everyone!

 

I'm back to ask for suggestions once again, mainly about the cameras, I don't know if I should open a new topic and if that's the case I'll do it right away.

 

Though I had decided to buy a used D7000 based on your directions, I have since discovered that I can't buy used cameras so I must stick to the new models.

 

Moreover, I have been given a limited budget as well which restricts the options (if we stay in the Nikon world of course) basically to the Nikon D3400 (might be that I'll be able to find a D5500 new within my budget but that doesn't seem easy at the moment).

 

I would prefer to stay in the Nikon world to avoid searching for possible adaptors to the lens I would use (Nikon E-series 50mm 1:1.8) which could prove to be a long quest.

 

So, is there anybody who could comment on the D3400 UV capabilities? I haven't found any feedback in the forum.

 

I thank you in advance for your inputs, cheers!

 

Nicola

Link to comment

Though I had decided to buy a used D7000 based on your directions, I have since discovered that I can't buy used cameras so I must stick to the new models.

 

I assume your institutional purchasing rules or grant requirements do not permit purchasing used equipment. You may wish to inform them that the modifications required to convert a camera will void the manufacturers warranty on a new camera. Also converting an older model with proven UV performance, especially if cited in scientific literature, would be preferred over "experimentation" with a new model with yet unproven UV capability.

Link to comment

Hi Nicola -

 

John's suggestion is a good one that you should explain to the granting institution that converting a new camera voids the warranty. So ask the granting institution for a waiver on that requirement that you must buy new.

 

If a waiver is not feasible to permit buying a used D7000, then the Nikon 3400 will be good for UV after conversion.

If you can find a new Panasonic Lumix camera (from the G line), that would be a good choice also. The Lumix cameras are very easy to use.

 

Please know that it is easy to find adapters to enable mounting a Nikon 50/1.8E to a Panasonic, Olympus, Canon, or Sony camera.

For example here, is a link to a Fotodiox adapter for mounting a Nikon F-mount lens to a Micro 4/3 body like a Panasonic or an Olympus camera.

https://www.fotodioxpro.com/products/nikf-mft

Link to comment

If you cannot buy used cameras then can you also not buy used lenses? The Nikon Series E has been out of production since the early 1980s.

 

F-mount lenses are easily adaptable to µ4/3 and adapters are cheap and plentiful but quality varies. The 50mm 1:1.8 E adapts nicely to my Panasonic G3s and G5. However, while it is considered UV capable it is only marginally so.

 

Several enlarger lenses are known to perform well in UV. If your institution still has a darkroom with some old film enlargers you should take inventory of any lenses that remain. Such lenses are commonly used mounted on bellows in macrophotography and should perform well in your research. The older chrome ring 80mm EL-Nikkor is particularly good for UV.

Link to comment

Thank you John and Andrea for your inputs!

 

A bit more of context: although I'll be using the UV equipment, I'm not actually the recipient of the grant (a fellow researcher of my laboratory is), I'm just managing the purchase based on the guidelines given to me.

Following your advice, I'll be writing to the granting institution to see if I can buy a used camera with a solid feedback in the UV range (I'll be looking at the models used in the literature as suggested by John).

 

I will also look into models of other companies than Nikon, though from my brief experience in searching for cameras here, the dichotomy Nikon-Canon seems to be pretty strong.

 

Thank you John for pointing out that the E-series is not actually the best option for UV-photography. I was going to use the 50mm because a friend of mine gave me almost unlimited access to his copy, which I tried with a UV-reflecting butterfly and a Nikon D70 obtaining what I was considering a good result (i'll ask if i can post some pictures to show you). Though it's true that I haven't compared it with other lenses in the same setup, so it might be that the UV reflectance I recorded was just a minimal part (which is good news and bad news at the same time). I'm not aware of darkrooms here at the university but I will look into it to see if there is any old equipment available.

 

So, I guess I'm almost back to square one, but with your suggestions at least I have some more routes to explore.

 

Thank you very much as always for taking some time to answer!

 

Cheers,

 

Nicola

Link to comment

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
×
×
  • Create New...