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UV Photography


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#1 Rick_UV

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Posted 30 March 2016 - 08:12 AM

Hello

 

I do UV body art in clubs. I struggle to take fotos of my art because of the overwhelming amount of blue/purple light thrown out by the uv lamps.

 

I have no control over the lamps but I was wondering what can be done when taking the fotos and after the foto has been taken.

 

I have attached a few fotos to show you what I usually get and what I would like to achieve.

 

1st+2nd are normal

3rd is the goal.

 

IMG_2114_zpsx3cg8wzo.jpg

IMG_2083_zpstoz0iyd2.jpg

IMG_1524_zps1rbvvtyn.jpg

 

I now have a Canon EOS 10D SLR, 

 

I was thinking that i should set it to ISO 1600, Shutter 100(?), F3.5 (lowest i think I can get it to.)

 

I was also thinking of getting a Yellow Lens filter to remove as much blue as possible.

 

No idea what to do post taking the image! Software to use? How to manipulate the images.

 

I assume I should take the images in RAW format.

 

Thanks in advance for help!

 

Rick



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#2 Chris Cosgrove

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Posted 30 March 2016 - 06:54 PM

The joy of low-light photography is that exposure is almost always a matter of try a setting and see if it works - if it doesn't, try a different one !

 

1600 ISO and 100th second sounds reasonable, but you appear to be working reasonably close to your subjects, f3.5 will give you very little depth of field and experimenting with yellow filters sounds promising, You could also try a straight UV filter often known as a 'skylight' filter.

 

As for image manipulation any of the leading image processing softwares should meet your needs - Adobe Photoshop (expensive), Serif PhotoPlus (much cheaper) or Gimp (free !). And using their level adjustment tools would allow you almost complete control over the output. And yes, RAW produces huge image files but allows much greater control in processing.

 

Those designs are gorgeous !

 

Chris Cosgrove



#3 Rick_UV

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Posted 31 March 2016 - 03:50 AM

I have Gimp - Which functions in Gimp would you suggest.

 

And how high would you go with the F number?

 

Thanks



#4 Chris Cosgrove

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Posted 31 March 2016 - 06:35 PM

To take these in reverse. I have no intention of writing a treatise on photography - there are plenty of works by more capable authors than me - but all photography is a matter of balancing trade-offs. Working in average to bright daylight the camera settings are relatively unimportant, almost any combination will give an acceptable image. Low light and extreme lighting is different, plus you are trying to do a form of portrait photography where you are reasonably close to your subjects, but at its simplest

 

More aperture - less depth of field - shorter exposures at any given ISO setting

Less aperture - more depth of field - longer exposures at any given ISO setting, and to add to this, the longer the lens the less depth of field at any given range !

 

Moving to Gimp, of the three I mentioned above this is the product I have the least familiarity with. I am currently using my Windows boot and I don't have it installed in Windows and it is too late at my night to re-boot over to Linux, but you will find that the channel tools and the various level tools can make a huge difference to an image. Given the lighting available to you you are never, I think, going to get any of these images to have natural skin tones or anything close but you will have a great deal of fun and frustration experimenting until you find settings that suit you !

 

Actually of the three images you showed I would say that all the second and third need is a touch more exposure.

 

Just one point to remember - always work with a copy of an image. If you screw up the copy you still have the original to go back to and make another copy.

 

Chris Cosgrove



#5 Chris Cosgrove

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Posted 01 April 2016 - 06:52 PM

I had a look at my version of Gimp in Linux this afternoon and then installed it into Windows as a check. I had great difficulty getting it to open the RAW format images out of my Nikon DSLR. My Nikon produces these images with the extension .NEF and Gimp doesn't seem to like them !  I did get a couple to open by changing the extension to .RAW but didn't have the time to try processing them.

 

This is something you might want to be aware of.

 

Chris Cosgrove



#6 Rick_UV

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Posted 06 April 2016 - 04:46 PM

Experimenting with a white mannequin head (not ideal)

 

RAW format - 250 shutter ... 3.5 aperture ... 1600 iso 

 

Post processing - 'Cloudy' white balance preset (UFraw) Reduced exposure to -0.80 ... De-noise 150.

 

Thoughts?

CRW_5072_zpsnejjeoiw.jpg

 

I will have an opportunity to photograph my art on skin at the weekend - I am hoping that the blue will be less on skin rather than white polystyrene!!

 

Rick






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