The x-y Easel - stepping easel for art repro

[teddillard]

Interesting...  though just another high-resolution single capture device that requires lighting the entire work, am I right?   

[Bart_van_der_Wolf]

Interesting...  though just another high-resolution single capture device that requires lighting the entire work, am I right?   

Hi Ted,

I agree, that's what it looks like, just high resolution. And given the time it takes to get an exposure, I wouldn't be surprised if it was a scanning device, requiring constant illumination and avoidance of any vibration during the long exposure time.

The benefit of a moving easel is that the illumination of a relatively smaller area can be optimized for uniformity and color (and even use the best part of the camera's image circle, which also allows to reduce flatness of field issues), and resolution can be varied by using different focal lengths and distances.

Cheers,
Bart

[John Nollendorfs]

Interesting...  though just another high-resolution single capture device that requires lighting the entire work, am I right?   

Ted, I don't know. I like your set-up, and I think it's a good design for average sized pieces. I have an acquaintance at the Nelson, in KC, and am trying to get a hold of him to get some first hand information about the Google Art Camera system.

[teddillard]

Hey Ted:
Did you see what Google has come up with? The "Art Camera"!
https://www.youtube.com/watch?v=dOrJesw5ET8

Funny.  Taking a close look at the video, it's a great example of how not to light a painting.  I'm guessing standard copy-board lighting, based on how the canvas reads.  There's not accurate texture of the brush strokes, certainly nothing that feels like a North Light studio, or even gallery lighting:



The resolution is great, sure, but like the Cruse, resolution without correct lighting won't give you the feel of the work as the artist saw it.  I wrote more about that here: https://teddillard.wordpress.com/2013/04/22/lighting-in-the-artists-studio-fine-art-reproduction-as-photography/

[teddillard]

Right - read more about the Google project here:
https://www.google.com/culturalinstitute/about/

It's not about faithful reproduction technology, it's about what Google does - making information available to people. 

On the one hand, it's a great initiative, but on the other, it could be so much better.  A friend of mine is the Director of Photography at a major museum here in the Northeast, and he laments the same thing - they want photos of the entire collection for their online catalogs, but don't want to pay/bother to do it right.   

[Zorki5]

Right - read more about the Google project here:
https://www.google.com/culturalinstitute/about/

More info in DPR's yesterday's article:
http://www.dpreview.com/news/1947958268/google-art-camera-uses-robotic-system-to-take-gigapixel-photos-of-museum-paintings

[teddillard]

I'll be really happy when "high-quality digitizations..."  means high-quality photography, not just the highest possible resolution.  Just sayin'.   

[teddillard]

Updates - I've been sidetracked by another project, but while shooting the other day I realized I use several things almost every day - especially the X-Rite Passport and the magnetic easel, AKA white board.  I just posted them up on the bottom of the Accessories page, here: https://xyeasel.wordpress.com/category/x-y-accessories/

Once I get a motorcycle out of my shop (that's another story...  lol) I'll get back to work on the lift drive for the new easel.  In the meantime I saw this on the way to work:
https://www.instagram.com/p/BGMs4pJNbXi/?taken-by=lifeinflux



I asked the guy what it was, and he said a radio control for this:
https://www.instagram.com/p/BGMtCPmtbXy/?taken-by=lifeinflux



He can run the lift from across the street, where he can actually see the load.  Welcome to the 21st Century!  By the time I get this thing built, it'll be the 22nd! 

[teddillard]

Some more updates.  I've been chatting with TTi, the vacuum easel guys, about some modifications for their big 30x40 model to work on the x-y Easel, and also with zig-align, the AMAzing tool for making sure your camera is square to the work.  It makes a YUGE difference in how well it stitches.  I'll be posting links to the site as soon as I have a chance. 

In the meantime I got the 12V DeWalt battery adapter set up, and mounted the motor controller.  Did another silly movie too:
https://www.instagram.com/p/BGhFqvctbWH/?taken-by=lifeinflux

One last step will hopefully be complete next week - coupling the vertical feed motor.  Parts are coming, progress is being made!   

[Bart_van_der_Wolf]

Ted, thanks again for the updates.

Some more updates.  I've been chatting with TTi, the vacuum easel guys, about some modifications for their big 30x40 model to work on the x-y Easel, and also with zig-align, the AMAzing tool for making sure your camera is square to the work.  It makes a YUGE difference in how well it stitches.  I'll be posting links to the site as soon as I have a chance.

Aligning the easel parallel with the sensor with the Zig-Align tool is one thing, but how sure are we that the surface of the artwork is parallel as well? With an unframed sheet on a vacuum-board that would be reliable if we can vacuum the Zig-Align as well, but framed artwork is slightly more iffy.

Looking forward to what you come up with.

Cheers,
Bart

[teddillard]

I use the zig-align on the art itself - set the painting up, set the mirror up hanging from a cord, resting square on the painting. 

But still, considering the field of view is about 16x20" (using a D800, and going for the dimensions of the file at 300ppi), and the camera is at about 50-60" using a 105 Micro-Nikkor, your margin of error is negligible. Even if you were 1/4" off, one side to the other, (which you'd have to be drinking to be... ) that'd be what?  .005% error?

Even when I'm lazy and just eyeball it, at f8 (about 2 1/2 or 3 stops from full wide open - optimum sharpness and even-field, from my testing of this particular lens) there's never any sharpness or focus issue, and the squareness after stitching the captures is always within the capabilities of Photoshop to correct (Edit>Transform>Distort)   

[BobDavid]

I use the zig-align on the art itself - set the painting up, set the mirror up hanging from a cord, resting square on the painting. 

But still, considering the field of view is about 16x20" (using a D800, and going for the dimensions of the file at 300ppi), and the camera is at about 50-60" using a 105 Micro-Nikkor, your margin of error is negligible. Even if you were 1/4" off, one side to the other, (which you'd have to be drinking to be... ) that'd be what?  .005% error?

Even when I'm lazy and just eyeball it, at f8 (about 2 1/2 or 3 stops from full wide open - optimum sharpness and even-field, from my testing of this particular lens) there's never any sharpness or focus issue, and the squareness after stitching the captures is always within the capabilities of Photoshop to correct (Edit>Transform>Distort)

The Nikon D800 is your weakest link in the chain. I wrestled with it for six months--never could get it to render "accurate" color. The best 35mm option today is the Pentax K-1. The files are stunning and it bypasses bayer interpolation when it is set to sensor-shift mode. I've been getting phenomenal results using an Actus view camera, a Rodagon APO 80mm f/4 N enarger lens and the multi-shot mode on the Oly E-M5 II. The color accuracy and DR of the Oly are nearly comparable and in some ways better than the files from the Hassey CF39-MS/Copy stand setup I used from 2008-2012. The Actus/Oly/APO 80 lens combo comes in at round $3K. I use a Starrett 135a pocket level for truing up the art and the camera. I'm retired now and use this kit for personal projects and helping out friends document artwork and documents. The EL is a flat field lens with excellent geometry and color rendering characteristics. Better lens choices are the Schneider 72mm Digitar/Copal 0 (shutter stays open) or the Rodensock Sironar 70mm. I'm sure there are excellent shorter focal length lenses in the Scheider/Rodenstock lineups. https://www.amazon.com/Starrett-135A-Pocket-Nickel-Plated-Finish/dp/B0002FS0XM?ie=UTF8&*Version*=1&*entries*=0

[teddillard]

The Nikon D800 is your weakest link in the chain. I wrestled with it for six months--never could get it to render "accurate" color.

I've never had a problem.  I use the X-Rite Passport to set up a camera profile in ACR, and get pretty much spot-on predictable color every time.  But then, my definition of "accurate color" depends on how fast and easily I can get a print that's faithful to the painting.   

[teddillard]

Got both motors installed and coupled, though the vertical drive needs a little fussing:
https://www.instagram.com/p/BGzCly4tbTY/?taken-by=lifeinflux

I can't wait to get this thing into the studio!  It beats the heck out of the old version...  and I made a few adjustments that give me about 6" more vertical travel as well. 

[Bart_van_der_Wolf]

Got both motors installed and coupled, though the vertical drive needs a little fussing:
https://www.instagram.com/p/BGzCly4tbTY/?taken-by=lifeinflux

I can't wait to get this thing into the studio!  It beats the heck out of the old version...  and I made a few adjustments that give me about 6" more vertical travel as well.

Congrats. Looking cool ...

Cheers,
Bart

[petermfiore]

Got both motors installed and coupled, though the vertical drive needs a little fussing:
https://www.instagram.com/p/BGzCly4tbTY/?taken-by=lifeinflux

I can't wait to get this thing into the studio!  It beats the heck out of the old version...  and I made a few adjustments that give me about 6" more vertical travel as well.

Hi Ted,
I'm wondering how large a painting can your X-Y easel accommodate?

[teddillard]

Hey Peter - the horizontal is pretty much limited only by your room and track length.  I've shot paintings over 6' wide.  On the vertical axis, the travel is about 40", but it can hold an 80" tall painting.  I have to do the math, but I reckon the biggest painting would be about 60" tall without having to reposition the work. I routinely shoot 60" tall paintings with my working rig now, but a lot of it depends on the stepping overlap you prefer and the resolution you're going for. 

Sorry, long day.  Clear as mud?   

[teddillard]

Happy Father's Day! 

I did some math on the new rig, and I'm coming up with a 55" to 60" maximum height for the painting, if you're shooting with a 16" x 24" frame area.  We'll see how that pans out in real life. 

The original plan was to turn the painting 90º if I needed to for a taller vertical.  I shoot a lot of portraits, and those guys like to go tall.  In that case I'd just light it as if the side is the top, if you get my meaning.  (I typically light to simulate a North Light studio with down spots, to emulate most painters studio lighting.)  As I said, the horizontal size is really only limited to your room size, since it's rolling on the floor (with, or without the tracks). 

The fact is, in actual use I've never had to do that. (I shoot artwork almost daily - I'm not retired, thanks BobDavid, but not for lack of tryin'  ) The really huge work I've shot hasn't exceeded 60" tall, and is more often just really wide - contemporary abstract artists in particular, but also mural work. 

The big work, though, is where you really start to get your head around the advantages of moving the work rather than the camera.  Compare, for the moment, the difference between lighting a 5' x 10' mural, and a 16" x 24" frame area.  amirite?   

[teddillard]

Simple things make me happy.  Like this:
https://www.instagram.com/p/BHXDt-MhvqE/?taken-by=lifeinflux

Believe it or not, it's taken me quite a while to put together a drive coupling for the feed screw that I liked.  The bracket holding the motor is just a temporary setup, but the coupling works like a champ!  (I'm sure anybody who's played with battlebots is laughing at me right now...  )

[BobShaw]

Good luck but to me it is a solution for a problem that doesn't exist. Unless the artwork was huge I would always capture in one click.