Orange Coneflower - Rudbeckia fulgida in reflected ultraviolet photography soft focus

Today about a question I carry around with me for long: "Is sharpness everything?" So here "pictorial" shots of a very decorative flower,Orange Coneflower - Rudbeckia fulgida in reflected ultraviolet soft focus photography using my "work horse" UV filter, the Baader-U and a UV/IR Cut filter for the visible light shots. Lens was a self made lens with quartz elements. Light source was sunlight. All shots were done with variable soft focus settings, SF0 - SF3.

All diptych images show left results using UV/Cut filter for the visible shots and right using the Baader-U filter (approx. 320-395nm, peak approx. 350nm) for the reflected UV shots.

[click on image to see a larger one]

 

 

 

 

Quadriptychs for comparison, first VIS then UV:
 

 


So, I have used variable soft focus settings, SF0 - SF3 and show the results in VIS and UV, the latter showing the prominent UV pattern this beautiful flower has, and all this gets nicely visible in this side-a-side presentation.

I have written previously about soft focus photography HERE.

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Quartz lens for reflected UV photography?

Today about using a quartz lens for reflected UV photography. I'm using quite rare Quartz Takumar f3.5 85mm for this and one of the few flowers available, a Phalaenopsis orchid, as well as my "work horse" UV filter, the Baader-U filter. Light source was sunlight and a Nichia UV LED (365nm). The questions was, how the image quality would turn out, knowing that such lenses should only be used for a quite narrow wavelength band (literature states between 10nm and 20nm depending on source), as these lenses are not chromatically corrected. All shots were done stopped down to f8, which is a usual working aperture to get enough DOF and sharpness.

[click on image to see a larger one]
Here some results:
visible light image using UV/IR cut filter:
 

multispectral image (i.e. unfiltered) and sunlight:
 

UV image using Baader-U filter and sunlight:
 

UV image using Baader-U filter and sunlight + 365nm UV LED:
 

Findings:
1) There is a substantial focusing difference, here 5mm between the UV (95mm) and the VIS image (100mm between front and camera mount), resulting in a 5% different image size when focused both (UV image is smaller). Distance orchid - camera was 700mm.
2) When white light is being used for visible photography, the 400-750nm band is quite broad, i.e. 350nm, which leads to quite visible CA (around edges), soft image and loss of contrast.
3) When white light is being used for multispectral (i.e. unfiltered ca 300-1100nm) photography, that band is even broader, leading to even softer images and loss of contrast.
4) Also the UV image taken in sunlight using a Baader-U filter (320-395nm i.e. 75nm bandwith) leads to rather soft images, but a bit better as the band is narrower, only 75nm wide.
5) The UV image taken in UV LED light at 365nm (ca 20nm bandwith) using a Baader-U filter leads to the best image, as here only the narrow 20nm bandwith of the UV LED around 365nm plays a role. The image is crisp, sharp (see structures on petals) and has a rather high contrast.

Conclusion is, that only if quasi monochromatic photography is being done (either using narrowband UV filters or narrowband UV light), acceptable results can be expected. For broadband UV photography, chromatically corrected UV lenses are required, such as quartz fluorite lenses.

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Negative Space used by Eschscholzia californica (California Poppy): UV ultraviolet photography

Today about Eschscholzia californica (California Poppy), which makes use of a very interesting concept: Negative Space. I made those shots at Herrmashof Park, Weinheim, Germany using a custom made up UV lens from a simple quartz singlet that I used before, stopped down mildly to various degrees to control a wanted soft focus effect. Shots in UV were done using the Baader-U filter and sunlight was used as light source.

[click on image to see a larger one]







The most interesting part, aside that soft focus effect was for me, how this California Poppy uses its pitch black petals (in UV) to make its anthers stand out brightly against that dark background by massively increasing contrast. To help attract pollinators? I would guess so...


Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Gazania rigens: Quartz Singlet Lens for Soft Focus Reflected UV Ultraviolet Photography III

Today a set of shots with a Gazania rigens flower that I have shot previously with a quartz-fluorite lens now using a custom made up UV lens from a simple quartz singlet that I used before, stopped down mildly to various degrees, so as to control a wanted soft focus effect. Shots were done using the Baader-U filter and sunlight as light source and "contra lucem".

[click on image to see a larger one]







So, I'm sure this is not to everyones taste, but on my way to explore other possibilities then just "scientific" shots, it is a welcome new style.

Part II is HERE

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Gazania: Quartz Singlet Lens for Soft Focus Reflected UV Ultraviolet Photography II

Today a set of shots with a different Gazania rigens flower that I have shot previously with a quartz-fluorite lens now using a custom made up UV lens from a simple quartz singlet that I used before, stopped down mildly to various degrees, so as to control a wanted soft focus effect. Shots were done using the Baader-U filter and sunlight as light source on my balcony with some glass mirror effect.

[click on image to see a larger one]







So, I'm sure this is not to everyones taste, but on my way to explore other possibilities then just "scientific" shots, it is a welcome new style.

Part I is HERE and part III is HERE

Stay tuned, more will follow on that fascinating subject...


More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Thistle: Quartz Singlet Lens for Soft Focus Reflected UV Ultraviolet Photography

Today a set of shots of a Thistle flower from Herrmashof Park, Weinheim, Germany using a custom made up UV lens from a simple quartz singlet that I used before, stopped down mildly to various degrees to control a wanted soft focus effect. Shots in UV were done using the Baader-U filter and sunlight was used as light source.

[click on image to see a larger one]







So, I'm sure this is not to everyones taste, but on my way to explore other possibilities then just "scientific" shots, it is a welcome new style.


Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Rudbeckia triloba: Quartz Singlet Lens for Soft Focus Reflected UV Ultraviolet Photography

Today a set of shots with a Rudbeckia triloba flower using a custom made up UV lens from a simple quartz singlet that I used before, stopped down mildly to various degrees to control a wanted soft focus effect. Shots in UV were done using the Baader-U filter and sunlight was used as light source.

[click on image to see a larger one]







So, I'm sure this is not to everyones taste, but on my way to explore other possibilities then just "scientific" shots, it is a welcome new style.


Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Gazania rigens: Quartz Singlet Lens for Soft Focus Reflected UV Ultraviolet Photography

Today a set of shots with a Gazania rigens flower that I have shot previously with a quartz-fluorite lens now using a custom made up UV lens from a simple quartz singlet that I used before, stopped down mildly to various degrees, so as to control a wanted soft focus effect. Shots were done using the Baader-U filter and sunlight as light source.

[click on image to see a larger one]







So, I'm sure this is not to everyones taste, but on my way to explore other possibilities then just "scientific" shots, it is a welcome new style.

Part II is HERE and part III is HERE

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Gazania rigens: human vision vs simulated bee vison using a quartz singlet lens for reflected UV ultraviolet photography (III)

This is a 3rd set of shots with the same flower Gazania rigens flower that I have shot previously with a quartz-fluorite lens and the same setup as in shots before using a custom made up UV lens from a simple quartz singlet, stopped down to around f16 (estimated as no scale). Shots are in normal human vision VIS, in UV using the Baader-U and Jupiter-U filter, as well as in simulated bee vision using my XBV2 and XBV3 filters respectively. Flower placed into the center, higher magnification, otherwise unchanged setup as before.

[click on image to see a larger one]

Visual shot:


Simulated bee vison using XBV3 filter:


Simulated bee vison using XBV2 filter:


Simulated bee vison using XBV5 filter:


UV using Baader-U filter:


UV using Jupiter-U filter:


I haven't re-adjusted the UV focus, so the rear of the flower drifts into blur, that could be avoided, if so wanted by individually adjusting focus for each shot.

I used a 365nm UV LED for focusing, that worked pretty well, even stopped down that much.

In my opinion this central placement is the best way to use this lens singlet, as it minimizes the visible blur, yet delivers acceptable sharpness in that whole spectral range.


Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Gazania rigens: human vision vs simulated bee vison using a quartz singlet lens for reflected UV ultraviolet photography (II)

This is a 2nd set of shots with the same flower Gazania rigens flower that I have shot previously with a quartz-fluorite lens and the same setup as in shots before using a custom made up UV lens from a simple quartz singlet, stopped down to around f16 (estimated as no scale). Shots are in normal human vision VIS, in UV using the Baader-U and Jupiter-U filter, as well as in simulated bee vision using my XBV2 and XBV3 filters respectively.

[click on image to see a larger one]

Visual shot:


Simulated bee vison using XBV3 filter:


Simulated bee vison using XBV2 filter:


Simulated bee vison using XBV5 filter:


UV using Baader-U filter:


UV using Jupiter-U filter:


The idea behind that 2nd set was to get a better estimate of the VIS-UV focus shift (measured 5.8%, VIS is quite larger) as well as to show the effect of out-of-center imaging, to get an idea how the blur develops. I guess that gets pretty clear now.


Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

Gazania rigens: human vision vs simulated bee vison using a quartz singlet lens for reflected UV ultraviolet photography

This is a Gazania rigens flower that I have shot before but now using a custom made up UV lens from a simple quartz singlet, stopped down to around f16 (estimated as no scale). Took some shots in normal human vision VIS, in UV using the Baader-U and Jupiter-U filter, as well as in simulated bee vision using my XBV2 and XBV3 filters respectively.

[click on image to see a larger one]

Visual shot:


Simulated bee vison using XBV3 filter:


Simulated bee vison using XBV2 filter:


UV using Baader-U filter:


UV using Jupiter-U filter:


So and here you have the comparison as a quadriptych VIS-UV-BV2-BV3:




Missed the focus at the visible shot a bit obviously since this lens is not color corrected, i.e. has some focus shift. As you may further notice, the center is quite sharp, but of course the more outside it gets, the more the blur increases. For flowers this can actually be quite nice in my opinion.

Well, of course I cannot make a decision for somebody else if an investment of a few hours work and, depending if a mechanic is needed or not, the cost for making such a lens mount is within budget, but surely such a quartz singlet could be, as it can be had new for about $100. There is inconvenience of course, due to the "substantial" focus shift, but lifeview solves that easily.

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

[UV] Barlow lens to eliminate vignetting when shooting in reflected UV

Today about using getting rid of vignetting when shooting reflected UV light and using older lenses. The rescue used here is a quartz Balow lens.

[click on image to see a larger one]
UV test image, left without and right with quartz Barlow lens:


White Clematis in UV:


That used Barlow lens enlarged the projected image by a factor of 1.4x, hence letting the vignetting disappear beyond the sensor borders.

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos

[UV] White Clematis in ultraviolet light using a quartz Focal Reducer lens

More shots using my white Clematis hybride I recently got. Here now using that before presented Spectrometer Quartz Fluorite Achromat f4/84mm lens with a 0.42x quartz Focal Reducer lens to make it a f1.7/35mm lens.

[click on image to see a larger one]

This UV image here also uses my standardized false UV color normal + high intensity palette:



White Clematis in UV:


and in visible light (VIS):


Differential VIS-UV:


The VIS-UV differential clearly shows, that despite the Focal Reducer, still hardly any focus shift is present.

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos