Jul 9 2014

1920’s Style Goosenecks

By Max


In my prior post on improvising a conduit bending machine, I mentioned that it was for a period reproduction lighting fixture for a theatrical project I was working on.  Well, the project is Speakeasy, and I’m happy to say that it’s up and running and getting great reviews.

So as you’d hope to find in a speakeasy, there’s a bar, and we wanted some more commercially styled lighting to go above it.  There were these gooseneck fixtures from the palettes I had put together, that we liked (top center):


My issue with the fixture as shown is that industrial chic wasn’t really a thing back then, in the way that in this day you can go to an upscale bar and all the lighting fixtures will be up-armored and distressed so that they look like they’re fifty years old.  Also, on a more practical level, period commercial lighting is a lot more difficult to find then residential lighting, and matching sets are pretty much impossible.

So I came up with this concept image, which retains the idea but it is a little more sophisticated implementation:

Concept image for the fixture

Concept image for the fixture

You’ll recall that we began with four freshly bent pieces of 1/2″ conduit:


I then cut bases out of MDF, improvising a jig to cut out the circles, and then around them with an ogee bit to do the corner detail:


Which, by the way, makes a fucking mess:


I cobbled together the rest of the connecting hardware from a pretty broad swath of departments at Home Despot:


And assembled:


I got a pretty acceptable bronze finish with a product called Rub n’ Buff.  Which has a hardcore following of the people who buy yard sale furniture and make it fab-ulous, so there’s plenty of good blog posts out there explaining how to use it, as it turns out.

Anyway, final shot of the bar.  I’ll write up some more on Speakeasy, which is one of the most ambitious theater projects I’ve done, soon.


Jun 1 2014

Breadboard-friendly i2c logic level converter

By Max

IMG_20140531_222803 (2)Lately I’ve been using my 5V Arduino in concert with 3.3V devices via i2c, and so I’ve found myself requiring an interface part to convert the two logic levels.

I had previously done this on the breadboard with two 2N7000 MOS-FETs according to this Philips application note AN97055:

i2c Logic Level Shifter Schematic

This worked, but it was a lot of parts to set up on the breadboard each time, and I wanted something hardwired so that I could focus on other things when it came time to troubleshoot.  So I cooked up this little guy:


Testing the waveform with an oscilliscope, you can see some noise is introduced on Channel 1, but I always wonder in these cases how much of that is just because I have a bunch of probes stuck everywhere– the act of measuring changes the measured behavior and so on.  But, it should be perfectly adequate for prototyping purposes.

i2c SCL line

5V signal in blue (channel 2). Resulting 3.3V signal in yellow.


If you’d like my Eagle files to incorporate this into your file, 3V to 5V i2c Eagle Files.

A pdf ready to etch is here: 3V to 5V i2c Eagle Files Level Shifter Rev0.

One note: if you look at the pictures of the finished product, you’ll see that rather than the usual way of doing things where you put the PCB on the bottom plane, then drill through and put the components on top, I’ve instead mirrored the layout, and soldered the components on the top plane.

 I did that so that I could solder the pin headers on top, as you can’t solder them to the bottom traces because the plastic connectors get in the way.  If you download the pdf I linked to, it’s already been flipped and is ready to go.  If you download the eagle files, make sure you select “mirror” from the print options.

Hope it comes in useful for you!


Apr 17 2014

Artwork for Craggin’s Lament, a Dungeons and Dragons campaign

By Max


Some of you may know I run a Sunday night Dungeons and Dragons campaign (specifically Pathfinder, with Roll20 for our virtual table top).  If that’s not your thing, move along, nothing to see here.What follows is artwork I’ve created for the dungeons that the party has explored over the last two years or so.  Mostly made on my tablet with Sketchbook Pro.


“Wading through cold, knee-deep water, you come upon a multi-story circular room, with a staircase winding around the perimeter.  From the ruined openings on each floor, water pours into the open space at the center with a deafening roar.  Cold mist lands on your face continually, and lichens and fungi line the walls.  Everything below the top three floors is filled with cold, turbulent water, and you can’t see how deep the chamber goes.”

The party needs to use the stairs to move from floor to floor.  But waiting in hiding are flying will-o-wisps, which can stun and enchant the party members, causing them to step off the stairs and fall into the water below.  They don’t take any damage from the fall per se, but the Hook Horror Darkfiends that live in the pool will try to pull them under.  Symbiosis!  Once someone fails their save, the remainder of the party has to think fast to save their wayward member.

This encounter was very nearly the last of the party’s stalwart mage, Baden Switch.

necromancer lair 4F1

“At the end of a long narrow tunnel you see a wan glow and have a sense that the corridor opens up to a sizable room.  As you creep closer, you see that the room is four stories, and contains an enormous brass machine that goes from the floor almost to the ceiling.  Pipes, manifolds, valves, and dials of obscure purpose branch out of it at every part, and there are bridges that connect to the pathway that runs around the center of the room at each of the upper levels.  As you get nearer, more of the lower structure of the machine comes into view, and you see that many of the pipes disappear into a rough-hewn opening in the wall, which is the source of the green glow that throws the room into relief.  The wall around the opening appears to have partially collapsed, and the machine itself seems to have undergone heavy damage at some point, and then repaired with clumsy haste.  It is dark, and silent in the chamber.  You don’t see any sign of the lich, although on the ground floor there are long wooden worktables covered with glass vials, oil burners, and papers.”

The first run-in with the lich, the party got bottled up in one of the small tunnels that lead into the room.  The lich cast Wall of Fire, filling the tunnel completely with opaque fire that does damage when you try and move through it, and the party had to retreat without landing a hit.  The second time, they were prepared and executed good tactics, prepping spells and buffs, entering from multiple tunnels at once, using surprise to good advantage, and engaging with melee fighters immediately.  On his first round, the lich cast Obscuring Mist, Quickened (minor action, effective spell level 4th), ran to the machine (move action), pulled a lever on it, and with scream of triumph, snapped the lever off completely. (standard, strength check DC 15).

“As everything in the chamber is shrouded in a dense white fog, you hear the machine roar to life, filling the echoing chamber with noise and making spoken communication difficult or impossible.”

It went badly for the party for a few rounds, but they still managed to unload a lot of damage, and at the end of the day liches just don’t have a lot of hit points.  The rift that the glow was coming out of was an open portal to another dimension, and on a high roll every round the machine would summon undead through the portal.   Which the lich could control (fun fact, they get Control Undead a certain number of times per day the way clerics get Channel Divinity).  But, as it happened, the machine never hit its numbers and the party cast Chill Metal (2nd level) on the pipes going into the rift, mostly neutralizing it.

UntitledHaving dispatched the lich, the party had the option to solve a puzzle to unlock the library, the room in blue behind the blue magical barrier on the first floor.  Shown is a screenshot from our virtual tabletop, Roll20.

Valley-Map-Parchment-WebFive years ago, gold was discovered at a sawmill near the hamlet of Craggin’s Lament.  The entire valley is now in the grips of a full scale gold rush, and prospectors, outlaws, gamblers, and merchants have transformed the town into a bustling jumping-off point for any who seek their fortune in the hills.  Hired to locate a missing merchant in a bandit-infested alpine pass, our heroes come into possession of an ancient map, showing the location of settlements of a dwarven empire forgotten by all but scholars of antiquity.  Exploring the ruins, the party soon becomes the focus of forces powerful and mysterious…

One of the very first handouts I made for the session.  Map drawn on paper, then scanned and the folds and paper background were added digitally.


Dungeon map for a low-level side quest published by Paizo, “The Forgotten King’s Tomb.”   Texture brush FTW.

Nov 27 2013

My Conduit Bending Machine

By Max
Concept image for the fixture

Concept image for the fixture

Oh hey there.  As part of the theater show I’m working on I’ve been making these industrial gooseneck type things for the bar lighting.  As you can see, a big part of it is the loop of conduit that goes up and around to support the fixture.  I figured, no problem, I’ll just get a conduit bender from Home Despot and bend it to suit.

You get some odd looks when you ride BART with a conduit bender.

You get some odd looks when you ride BART with a conduit bender.

So that was a disaster.  I could get bends up to 90 degrees just fine, but after that the bender would start to slip on the conduit and I would get squircles rather than a continuous loop like I wanted.   My results could be summarized thusly:

conduit diagram1

As I am nothing if not persistent, I went to the idea store and came up with this:



There’s a circle cut from MDF on the inside radius of the conduit.  As the handle is turned, it pulls the conduit in, and it’s forced to bend around the circle.  I had to ask a dancer stand on it while I was bending it to get enough torque (thanks, Cici!) and it has a tendency to pulverize the MDF at the working surfaces, but heyo it works!



Conduit being pulled into the break

Here’s a sneak peek work-in-progress picture of the fixtures I’m building:


I am aiming to be America’s #1 blog on improvised conduit bending machines, so more on this topic soon!

Oct 29 2013

Happy Birthday Mom and Dad!

By Max
Happy Birthday Dad!

Happy Birthday Dad!

Happy Birthday Mom!

Oct 19 2013

1920’s Lighting Fixture Research

By Max

HistoricCatalogsofSearsRoebuckandCo.1896-1993 (4)

Quick, to the Microfiche!:  I’m working on a live performance project right now that I’m really excited about.  It’s an immersive theater piece set in 1923, so we’ve made the design choice that we’re going to try do everything with period lighting fixtures, or conceal anything that’s incorrect to the time period.   Which, it turns out in practice, is a completely insane thing to try and do.  But anyway.

To get started, I wanted a visual survey of typical lighting fixtures as would be found in 1923, so that when we were designing the interiors we would have a rich palette to draw from.  For visual research, I first did the simplest thing, which was to open a bottle of wine, dim the lights, and search for pictures taken in the 20’s on the Internet.

A 1920's Speakeasy

My research indicates they knew how to have a good time back in the day.

There are some good resources out there, like the enthralling timewaster that is the Library of Congress Flickr collection, but the images I found this way weren’t terribly helpful.  The lion’s share of photographs were taken outdoors, which doesn’t help me.  If they were taken indoors, the ambient lighting would be obscured by the camera flash.  One can gather that typical interior light levels were much lower than they are today, but apart from that I couldn’t tell much.

HistoricCatalogsofSearsRoebuckandCo.1896-1993 (3)

Frontispiece of the 1923 Sears Roebuck Catalog

Next Idea.  So then I thought of the Sears Catalog.  At its heyday in the 20’s, you could buy anything, up to and including an entire house in kit form, from the Sears Catalog– the amazon.com of its day.  And, the San Francisco Public Library has a complete set  on microfiche, dating back to the 1890’s.

I spent a thoroughly enjoyable Saturday at the library going through the collection, starting from about 1910 and going forward through 1930.  At the end of it, I had what I wanted:

1920's Wall Sconces

Adjusto-Lite, The Handiest Lamp Made.

1920's Table Lamps

We ♥ Fringes

1920's Floor Lamps

My Radio Has Made Me $500.

1920's Chandeliers

“All positive statements are verified in our own laboratory.”

1920's Ceiling Surface Lighting Fixtures

Note that the light bulbs were still mouth-blown, which is why they have the tips on the end.

I found that the most stylistically expressed years were actually 1927-29 or so, although the early 20’s have some great details.  Also, there’s a noticeable shift through the decade in the marketing copy (and what great copy it is, too)– the earlier years are all about thrift, but as the Roaring 20’s kick in in earnest, the pitch changes to all the modern electric appliances you can own, in your own home.

If you have any resources to share, leave a comment!  I will try to post more about this monster of a project as we get closer to the opening in January.

Aug 23 2013

In Appreciation: J. Robert Anderson

By Max

J. Robert Anderson, Uncle Bob to me

Regular service will resume shortly: I want to say a few words about my Uncle Bob, who passed away a few weeks ago.  At the funeral, the priest asked us to reflect on what his life meant to us, the gifts he gave us by his presence in our life.  I’ve been turning that question over and over in my mind, trying to process it.

Aunt Carole and Uncle Bob, in Chicago, 1988 or so

Every summer, my parents would send both of us to visit my aunt Carole and uncle Bob for a month or so, while they took off and had an adult-person vacation.  At the time lived in a high-rise condo in Chicago, and we also took their sailboat out on Lake Michigan, and camped in the Chicago Harbor, and watched the fireworks from their windows.


View from their boat, in the Chicago Marina

I was really into science, and they indulged me, spending two whole days at the Chicago Museum of Natural History (because we didn’t see everything the first day!), and detailed discussions of dinosaurs or spaceflight or sharks or god knows what else.


My sister and I on the boat, Chicago, 1988 or so

In later years, we caught fish from their dock in Akron, OH, and we tried our first lobster when they moved to Long Island, NY.  They retired in Lake Tahoe, NV.  Always, near the water.

Lake Tahoe, NV

But more than the memories of the experiences, I feel like I’m a different person for the time we spent together, and I’ve been struggling to find the words to explain this.  I think that the simple act of being an extended guest with adults that aren’t your parents was formative for me— never mind in such wonderful and exotic locales.  I grew up (until the age of 13) in Minneapolis, MN, which, while being a great place to raise kids, can be a little bit of a monoculture.  Staying with my Aunt Carole and Uncle Bob gave me the idea that there were other ways of being, other rulesets to live by.  That intellectual flexibility, the ability to see the-way-things-are as a somewhat arbitrary construct of expectation, has served me well as an artist.

2009-11-26 14.39.18

The other gift my uncle gave me was to engage me as an intellectual peer.  I didn’t particularly get along with kids my own age, and adults tended to treat me like, well, a kid.  My uncle was a salty old Navy guy, just full of piss and vinegar.  He had a pretty wicked sense of humor, and he didn’t particularly spare me any of his barbs.

I guess I should here mention that he was a Stanford graduate, and rose to #2 at Ford under Lee Iacocca before becoming CFO and vice-chairman at Firestone and CEO and vice-chairman at Grumman Corporation, makers of the Apollo Lunar Module and F-14 fighter jet.

Bob in a jet simulator

Bob in a jet simulator

I’ll miss his wry smile and sharp wit.

2009-11-25 17.06.18

Aug 1 2013

LEED v4 for the Lighting Designer

By Max

Leed Logo

The next version of LEED is coming… Slowly. What was originally slated to be LEED 2012 has been approved by membership and will be rolled out sometime early 2014.  In LEED 2009 there were really only four credits where a lighting designer could contribute to project certification:

  • SS Credit 8: Light Pollution Reduction
  • EA Credit 1: Optimize Energy Performance
  • IEQ Credit 6.1: Controllability of Systems – Lighting
  • IEQ Credit 8.1: Daylight and Views – Daylight

In LEED v4, these credits have been revised, and new credits relevant to lighting design have been established.  Let’s see what’s new, shall we?



Light Pollution Reduction (Sustainable Sites Credit 8):

This credit is frankly a mess in LEED 2009, and it seems much improved and clarified in v4.

In LEED 2009, you had to demonstrate that all interior fixtures with line-of-sight to exterior windows had an automatic shutoff to reduce their levels by 50% after curfew, to prevent light pollution.  Which was a lot of documentation for a fairly minimal environmental impact.  In v4, all LEED Projects will be required to demonstrate a minimum level of energy performance over ASHRAE 90.1-2010, which accomplishes essentially the same thing without creating a documentation requirement specific to the credit.

The light trespass requirement is also streamlined.  In LEED 2009, the light trespass criteria included both a horizontal and vertical footcandle maximum, which varied by Lighting Zone, without a lot of specificity in how the criteria should be documented.  In addition, the horizontal footcandle requirement was <.01 fc, which meant that if you had a high-density design with lighting anywhere near the LEED boundary, this credit was nearly impossible to attain– even if your exterior lighting very sensible and dark-sky friendly.  In LEED v4, there is only a vertical footcandle requirement, with clear guidance on how the calcgrids should be built, OR you can comply by using fixtures with an appropriate BUG rating.

A similar alternate compliance method to the uplight requirement is provided– you can specify fixtures with an appropriate BUG rating for the Lighting Zone and distance to the LEED boundary, and forgo summing uplight/downlight lumens for every fixture on the site.

What these two changes mean together is that you can identify a maximum BUG rating for your project, specify fixtures with that BUG rating or less, and you’re done.  Also, and I can’t emphasize how welcome this change is– facade and landscape lighting are exempt from trespass and uplight requirements, as long as you turn them off between midnight and 6am.    Facade and landscape lighting has a role to play in creating facilities that serve the needs of occupants, and if you’re designing to meet the exterior lighting load requirements of ASHRAE 90.1-2010 and furthermore turning the lighting  off after hours the environmental impact of these load types are minimal.

Link to the full credit language is here.



Optimize Energy Performance (Energy and Atmosphere Credit 2):

The credit language is now based on ASHRAE 90.1-2010, which seems to be the biggest change.  As before, there’s a whole-building energy modeling compliance path, or a prescriptive path.  The design guides used as the basis of the prescriptive path has been similarly updated.  I haven’t yet dug into exactly what’s different with ASHRAE 90.1-2007 to 2010, if you have insights be sure to leave a comment.

Link to the full credit language is here.


An Electrical Submeter

Advanced Energy Metering (Energy and Atmosphere Credit 3):

This is a new credit that would require placing a submeter on loads that exceed 10% of the total energy usage, which would certainly be the lighting panel, and possibly individual loads within that panel.  Submeters are available at around $300/zone, so it’s a very easy and inexpensive way to pick up a credit.  Some lighting control systems have load metering capability built-in, so you could get it for nearly free.  I think the intent here is to make it a credit that nearly every LEED project pursues, thereby creating a market for this sort of product, and an expectation on the part of owners that they’ll be able to monitor the energy performance of their buildings on a granular and ongoing basis.

Link to the full credit language is here.


Demand Response

Demand Response (Energy and Atmosphere Credit 4):

Demand Response (DR) works like this: utilities are continually scaling up and down the amount of power generation in the system, and during periods of peak use or rapid changes in system energy usage, they have to run their dirtiest plants.  DR is a way of managing those peak and transient loads, whereby the utility sends an electronic request to the energy consumers, who automatically turn off some loads.  For example, a facility might increase the HVAC setpoint by a few degrees, or wait to run the compressor on their refrigeration equipment, or sweep lighting in spaces that are unoccupied to off.  In return, the utility offers the consumer rebates or reduced rates.

If your project is in California this credit is a freebie, since Title 24 will require DR capability in all new projects beginning in 2014.  As utilities move towards demand-pricing of energy, this capability can potentially be a real money saver.  Some lighting controls systems have the ability to do Demand Response built-in.

Again, it seems like the intent here is to create a market, since this credit would be fairly easy and inexpensive to attain.

Link to the full credit language is here.


West Berkeley Library, Pseudocolor rendering

Interior Lighting (Indoor Environmental Quality Credit 6):

This credit incorporates the former Controllability of Systems – Lighting credit (IEQ 6.1), with the further requirement spaces have bi-level switching.  In California, the next version of Title 24 requires continuous dimming in most spaces, so this is a freebie for projects located in the golden state.

As before, that’s worth one credit, but what’s this? A completely new point, for ‘Lighting Quality’.  I’m just going to block quote this one:

Option 2. Lighting quality (1 point)

Choose four of the following strategies.

    1. For all regularly occupied spaces, use light fixtures with a luminance of less than 2,500cd/m2 between 45 and 90 degrees from nadir.
      Exceptions include wallwash fixtures properly aimed at walls, as specified by manufacturer’s data, indirect uplighting fixtures, provided there is no view down into these uplights from a regularly occupied space above, and any other specific applications (i.e. adjustable fixtures).
    2. For the entire project, use light sources with a CRI of 80 or higher. Exceptions include lamps or fixtures specifically designed to provide colored lighting for effect, site lighting, or other special use.
    3. For 75% of the total connected lighting load, use light sources that have a rated life (or L70 for LED sources) of at least 24,000 hours (at 3-hour per start, if applicable).
    4. Use direct-only overhead lighting for 25% or less of the total connected lighting load for all regularly occupied spaces.
    5. For 90% of the regularly occupied floor area, meet the following thresholds for area-weighted average surface reflectance: 85% for ceilings, 60% for walls, and 25% for floors.
    6. If furniture is included in the scope of work, select furniture finishes to meet the following thresholds for area-weighted average surface reflectance: 45% for work surfaces, and 50% for movable partitions.
    7. For 75% of the regularly occupied floor area, meet an average ratio of wall surface illuminance (excluding fenestration) to average work plane (or surface, if defined) illuminance that does not exceed 1:10. Must also meet strategy (5), strategy (6), or demonstrate area-weighted surface reflectance of 60% for walls.
    8. For 75% of the regularly occupied floor area, meet an average ratio of ceiling illuminance (excluding fenestration) to work surface illuminance that does not exceed 1:10. Must also meet option (5), option (6), or demonstrate area-weighted surface reflectance of 85% for ceilings.

Well.  I’m sure some in our industry will bristle at being told what constitutes quality in lighting, but most of these are best practices, criteria that we would design to meet in any case.  Some of them are pretty subjective (some of our clients very much prefer darker finishes and direct lighting), but that’s why you can pick any four, I suppose.  I generally take the view that any attempt to promote quality in lighting design is welcome, as long as there’s some flexibility in implementation.

Link to the full credit language is here.


Daylighting Room

Daylight (Indoor Environmental Quality Credit 7)

Here’s another one where the language of the credit has received a much-needed overhaul— the process of documenting the credit is now much clearer.  But the biggest change is that the Prescriptive option based on ratio of window space to floor space has been eliminated in favor of a new performance metric based Solar Daylight Autonomy (SDA).  The new criteria is SDA(300/50%), which means that calculation points in regularly occupied areas have 300 lux or more 50% of the time.  In addition, you must demonstrate that no more than 10% of calculation points have an Annual Solar Exposure of ASE(1000,250), meaning that no more than 10% of spaces have more than 1000 lux more than 250 hours per year.

The available points from this credit have been increased, 55% SDA(300/50%) will get you two points, 75% will get you three points, reflecting the rather large potential impact on the floorplate and glazing system that would be necessary to obtain this credit.   Alternatively, you can use the same metric found in LEED 2009, demonstrating that at 9am and 3pm on the equinox, most of your floor area will be between 300 lux and 3000 lux.  Interesting, that compliance method only nets you a maximum of two points.

As in prior versions, there’s also a compliance path via direct measurement of the built environment, but I wouldn’t expect projects to pursue this strategy except as a Hail Mary.

If you need a quick refresher on daylighting metrics like SDA and ASE, my blog post on the subject of daylighting metrics is here.

Link to the full credit language is here.

Final thoughts:  In general, I have to say that I’m well pleased with the changes.  Where in the past high-performing projects could nevertheless fail to comply with the specifics of a credit, multiple paths to compliance have been provided, and they’re based on industry standards, rather than some standard  particular to LEED.   The credits have been rewritten with a lot of care taken to make the language clear and specific.  If I’m understanding it right, the overall point totals that make a project LEED Certified, Silver, Gold, or Platinum are not changing, so perhaps the biggest change is that project teams will have a wider choice in certification strategies.

Hope this post came in useful, chime in in the comments if you have anything to add!

Jun 30 2013

Backpacking Lassen Volcanic National Park

By Max

Bush lupine

Lassen is a gem.  The Southwest part of the park was still mostly under snow when I was there in the second week of June, but Hwy 89, which runs over Lassen Pass at 8500ft, had just opened for the summer a week or two before.  I did a 27 mile loop around the Eastern side of the park.  Days were in the mid-70s, nights were down to freezing.


Pictures from four days of waterfalls, mountain lakes, and volcanic formations follow!

Continue reading “Backpacking Lassen Volcanic National Park” »

Jun 16 2013

Kitchen Lighting!

By Max


Le Corbusier had to start somewhere, I suppose:  Here’s a fun little side project I recently completed.  My parents are sprucing up their house in preparation to sell it, and as part of that effort the currently installed kitchen lighting Had To Go.

The existing Monstrosity as it was referred to in the family was the the same fixture that came with the house when we moved into it in 1994: a 6′ x 8′ box built out of drywall, with three fluorescent striplights inside (T12, natch).  The diffusers consisted of three sheets of A12 prismatic arcylic.   Behold:


An interesting artifact of the market distortions caused by very inexpensive labor.

Anyway, my parents decided that they had lived under its all-seeing tyranny long enough, but wanted to keep the scope of the project to a minimum since they’re trying to sell the house.  At the same time, the kitchen is the first thing when you enter from the garage, so they wanted to create an architectural feature.  After working through a few design iterations, we arrived at the following (rendered via AGI32):


All of the fixtures are MR-16 downlights from Contrast Lighting.  The six in the center pattern have a dropped frosted glass cylinder trims:

regressed downlight from Scan rev 2

While the downlights around the perimeter have a complementary regressed frosted glass housing:regressed downlight from Scan rev 1

Sectional view:regressed downlight from Scan rev 4


We’re all pretty happy with the way it came out, Contrast really delivers an exceptional quality of product, especially at the reasonable price, and the contractors did a nice job finishing it out:IMG_0974-rev1