Howdy from Waxahachie Texas USA

[dancingcat]

Glad to find y'all... starting a UV plant photography project for the Botanical Research Institute of Texas.

Need help on UV filters for a converted Olympus EM1m2 - have normal zoom lens and 60 mm macro lens.

Sending my EM1 off for conversion. Can't wait to start seeing like a bee... :-)

[dabateman]

I look forward to seeing how the Em1mk2 performs.  I am loving my Em5mk2 and Em1mk1 full spectrum cameras.

The Olympus 60mm macro isn't so good for UV reflectance photography,  but will work for UV induced fluorescence.  If your normal zoom lens is the 14-42mm R2 f3.5/5.6, that surprisingly works well for UV photography. 

As for native m43rds lenses,  the Sigma 30mm f2.8 lens,  followed by Sigma 19mm f2.8 lens and Olympus 30mm f3.5 macro are good. I haven't tested the Sigma 60mm f2.8 lens,  but its also reported to work.

If you start adapting lenses,  then my favorite is the Canon 40mm STM f2.8 lens or manual focus Nikon EL old metal 80mm f5.6  enlarger lens. 

 

Filters will depend on your budget.  But the Baader venus u filter is excellent.  Or a stack of either Hoya 2mm U340 or 2mm U360 with 2mm Schott S8612.

Also the Hoya 1.5mm U330 will get you seeing like a bee.

 

[dancingcat]

my normal zoom is the 12-40mm pro, and I have a 25 mm prime, both Oly.  probably I will invest in the Baader filter .. what I’ve read says it doesn’t have much IR interference.  but still learning..    who did your conversion?

[Nate]

Welcome to UVP, I'm still new to UV also, but learning a bunch here. I have the Baader venus and it's great. If you decide to get it, It has 48mm threads, and I just use a step up adapter. Looking forward to seeing your UV project

[dabateman]

2 hours ago, suefrary said:

my normal zoom is the 12-40mm pro, and I have a 25 mm prime, both Oly.  probably I will invest in the Baader filter .. what I’ve read says it doesn’t have much IR interference.  but still learning..    who did your conversion?

I went with Kolarivision as they were the only ones whom would replace with fused silica. I also sent in my four thirds 9-18mm lens with adapter,  to ensure infinity focus in IR. I also had the dust shaker removed on both cameras to maximize UV detection. 

 

Yes my first UV filter was the Baader venus u filter.  Its excellent and still my overall favorite.  But I have also gone a little overboard and bought most other UV filters to obtain different colors.  It was my only UV filter from 2008 to 2018. 

[nfoto]

Welcome to UVP and hope you will find the site helpful. We are looking forward to strengthen our botanical expertise !!

[dancingcat]

Thanks dbateman... I will probably use Kolari to do the conversion and get the Baader U filter.

As to lenses - Olympus seems to have coated mine with "antireflective" stuff - I haven't been able to find transmission graphs online, or a description of the chemistry of the coating,  but I'd assume that might degrade the transmission in the blue end. 

I'll try my existing lenses first, probably the Zuiko 25mm f/1:1.8 prime (50mm full frame equiv). Hopefully its fast enough to overcome any degraded transmission in the UV.   If anyone knows where there's a transmission graph for that one, I'd appreciate a link, or firsthand experience would be even better.

 

I am a member of the Texas Master Naturalists as well as working for the Botanical Research Institute in Fort Worth... the Master Naturalist group are volunteers who educate both kids and adults about the natural world - and our UV plant project "see like a bee" is in part to help educate folks on how bees do their thing, and how flowers have evolved to take advantage of bee vision (or vice versa, not sure if bees adapted to flowers or flowers adapted to bees :-).

 

So my photographs will be both for science at the BRIT Herbarium, to compare live and dried specimens - and for teaching.

I really appreciate you folks.  Glad to have found you.

[Andrea B.]

Hello Sue and welcome to UVP! I hope you can find lots of good information about reflected UV photography.

 

There is a beginner's list of gear found here: https://www.ultravioletphotography.com/content/index.php?/topic/4805-best-basic-gear-goggles-bg-filters-torches/

 

There is information about lenses and filters and white balance in the Stickies section and in the UV Lens Technical Data section. Several members use Olympus conversions and have discussed lenses for Olys. If you search on "Olympus", you should be able to find something helpful.

 

 

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The earth has had bees for about 130 million years. Bees and flowers co-evolved for mutual benefit,

although flowers do have other pollination strategies not involving bees (as I'm sure you know!).

 

I have a couple of posters which have been used for "bee vision" educational purposes. I'm always happy to license them for that. Here is a link to an updated version of a poster originally made for the U. of Nebraska Agricultural Extension a few years ago. There is a link on the poster to the website of Dr. Adrian Horridge who has done extensive research on bee vision.

https://www.ultravioletphotography.com/content/index.php?/topic/4846-the-bee-sees-a-dandelion-poster-template/#comment-49573

 

Bees do not form images of flowers like we do. They use their green detectors to find edges. They detect contrasts of foreground to background. They detect to blue reflecting areas. Bees use UV light from the sun to determine which way is "up" and for directional purposes.

 

Here is a link to another poster which attempts to illustrate the difference between "bee colors", the UV camera's false colors, and how bees actually detect a flower like a Shasta Daisy using edges, lights/darks and reflected blue. This is a huge over-simplification of the very complex bee vision, of course, but it does illustrate some important points.

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This next poster illustrates human vision, camera UV vision and bee vision for a typical sunflower. A reflected UV photograph made with a UV-pass filter only shows one aspect of bee vision. You might want to get a filter stack which passes UV+Blue+Green. After white-balancing the UV+B+G photo, the result (first row on the right) better illustrates the areas of a flower to which a bee responds.

There is no way to illustrate reflected UV as a "color", so on the second row left, I used a speckled area to indicate the region on the flower which was reflecting both yellow and UV.

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We also have lots and lots of floral UV signatures in the botanical section which might be useful to you.

 

[Bill De Jager]

Welcome, Sue! 

 

I've tested the Sigma 60mm f/2.8 in monochrome UV and it works pretty well in that mode as an 'accidental' UV lens, but have no idea yet of how well it deals with UV 'colors'.  My wife found out that she likes it when I buy some cut sunflowers for UV photography and they spend 95% of their time brightening up the kitchen (the room that gets morning sun in this house).  So I expect to be doing some more tests soon.

 

I see that your town is right in the path of the 2024 total solar eclipse.