Reflected UV image with converted flash - image

[Doug A]

One of my first reflected UV shots with UV modified Pentax AF540 flash. Pentax K-1, Pentax bellows with 3 extension tubes, Nikon El-Nikkor 135 f5.6 enlarging lens. Bellows has a handy internal filter thread to allow filters to be mounted inside  it. Used  the Ioriginal supplied ZWB-1 2mm/ BG39 2.3mm filter stack. The flash was placed less than 2" from flower. Flash had 2 2mm  filters, probably ZWB-1, borrowed from 2 NEMO torches. The extra 4mm of flash filtration is required to squelch leakage.  Exposure f16 1/200 ISO2000.

 

This flower is very small at about 10mm. Magnification is close to 2x life size. This image was slightly cropped for composition. Lens was used at f16 and would probably

perform better reversed. Unfortunately, I don't have the necessary adapters to do that yet. I may wait to do this since the 135mm lens really is too long of a focal length to work comfortably on the bellows at these magnifications. Looking for an El-Nikkor 80mm for these applications.

 

Any suggestions welcome.

Thanks for looking,

Doug A

 

 

[nfoto]

Nice first try.

 

A Potentilla or some other closely related genus, which shows the farily classic UV dark petal pattern. Foliage is medium dark and grey as expected.

 

If there is one thing to critisise that would be the lighting setup which allows too much shading inside the flower. If you only have a single flash head you should look into using a large reflector.

 

ISO 2000? really - is this a typing error? With a flash unit up close ISO 100 would be my normal starting point.

[Doug A]

11 minutes ago, nfoto said:

Nice first try.

 

A Potentilla or some other closely related genus, which shows the farily classic UV dark petal pattern. Foliage is medium dark and grey as expected.

 

If there is one thing to critisise that would be the lighting setup which allows too much shading inside the flower. If you only have a single flash head you should look into using a large reflector.

 

ISO 2000? really - is this a typing error? With a flash unit up close ISO 100 would be my normal starting point.

Thank you@nfoto.  Yes it was really ISO 2000. This was a quick experiment to see if I could get correct WB with filtered UV flash. The NEMO  torch filters are small and barely covered the flash tube. The flash reflector was masked down to fit. There should be more light when the flash sized filters arrive. There's also light loss due to the full bellows draw and 3 extension tubes. Will eliminate the tubes when I pick up a Nikon El-Nikkor 80mm lens.

 

Agree about getting more light in the center. I was planning on shooting dandelions, but they had all closed up by noon time. Not sure why they did that.

 

Thanks for looking and the feedback,

Doug A

[nfoto]

On a side note, "dandelions" closing up by noon likely are not true member of Taraxacum the dandelion genus, but Tragopogon or suchlike species.

[Andy Perrin]

A good start!

[Andrea B.]

For any flash which can be fired while off the hotshoe, set the exposure time to 15-30 seconds and make multiple flashes -- for example, one from each side and one from the top -- to fully illuminate a close-up flower or other subject. My old Nikon SB flashes can be run off a battery pack, so they can be fired off the hotshoe in order to make use of this multiple flash technique.

 

Can your Pentax flash be run this way off of a battery pack?

[Doug A]

@Andrea B.yes it can run off a battery pack. Haven't tried multi-pop with UVR yet. Used it with a UVIVF shot with good results. Still need to edit it before posting. 

 

Thanks,

Doug A