Discussing the histogram, one of the most important tools in Photoshop.

Rocky Kenworthy, founder of Dot Editions hosted a Digital Printing Discussion in his Brooklyn print studio. Twenty-five  photographers braved the winter weather warnings and attended the open-forum discussion, armed with questions about archival pigment printing, paper choices, monitor calibration, and RIP software. Rocky shared his knowledge about how to work an image into an optimal archival pigment print, trouble-shooting imaging problems, paper choices, and RIP software.

What the photographers are saying about the event:

“I was very impressed with your studio. I think having the open discussion on file Prep, & printing was a great idea. Now my head is spinning with all the new info.” – Patrick McCarthy

“I enjoyed being there last night, I think its a great idea.” – Bart Michiels

“Last night the print with RIP and without RIP were quiet interesting to see…” - Frank Fournier

“Rocky does a very good job sharing with us what he knows and at the same time being open to what others are experiencing.  My own experience with coming to digital with a longer ‘film’ background gives me similar feelings, that nothing is written in stone, and you simply have to experiment. … I think you both provide a nice environment and i feel the information is treated with enough depth that i can take it further, without so much depth that the discussion just becomes obtuse.” - Richard Rethmeyer

“Thank you for having the event!  I definitely learned some helpful techniques and Rocky was very generous about sharing his knowledge.  It was much appreciated.” – Carey Kirkella

Discussion of paper choices for archival pigment printing.

We are looking forward  to hosting more of these community-minded forums about the process of archival pigment printing in the future! If you are interested in being part of the discussion, please sign up for our mailing list, or become a friend of Dot Editions on Facebook!

High Dynamic Range Imaging is a method of creating 32-bit images that captures all the light in a scene, allowing detail in  the very brightest highlight and in the deepest  shadows of an image. The image is created by exposure bracketing, and then merging the images into an HDR image (for best results, bracket 5-7 exposures. Use a tripod, and bracket with the shutter speed, not the aperture, so you’re not changing the focus. More info on how to create an HDR here.).

Once you merge the exposures into one HDR, you get an image file called openEXR, which  shows all the light values within one scene with a slider. Here’s an example of one image with the  slider in 3 different places, illustrating the light in all parts of the same scene.

Now it’s time to work on your 32-bit image. You don’t have to immediately tone-map your image. (Tone-mapping simply means compressing a 32-bit file to a more manageable 16 bit). There is a lot you can do in 32 bit in Photoshop, but not a whole lot of information out there about how to do it. There are certain tools in Photoshop that work with 32 bit – though you must have the Extended version of either CS3 or CS4. And don’t immediately go to one of the tone-mapping softwares (such as Picturenaut or Photomatix) – though you have some control, images often end up looking haloed or solarized.

Some tools that you can use in 32-bit are Exposure, Levels, Gradient Tool, Hue/Saturation, and others. You’ll see that some things, like Curves or the healing brush, do not work, or that some tools work a bit differently. Really, getting the hang of working in 32-bit just takes experimentation, patience, and a lot of hard drive space. Also, you’ll find that masking can be tricky, but again, have some patience with it until you get results you are happy with.

Here is an example of an HDR that still has all the information, in 32-bit. You can even “turn-on” the lights in 32-bit, as in the right example, by selectively adjusting the exposure.

Once you are happy with the exposure, you can then bring it into 16 bit to finalize the image. Go to Image/Mode, and select 16 bit. You’ll get some options, on this example, I chose Exposure/Gamma, but try different choices to see their effect.

So now you are armed with more information about how to work with HDR images that look realistic.

For more information, Christian Bloch’s book The HDRI Handbook and his website www.hdrlabs.com is very informative. Also check out Dot’s HDR page for more info and examples.

Please send us images that you come up with!