Hey I really admire your passion and how much you love to share what you do. I just want to share my bit: you did right but only addressed the first half of process. So    let's go by steps!:
1) You expose for the darkest areas where you want to save some details. As we know the shadows end up pretty thin on film and below a given density all details are lost. So you did right, point your spot meter on the darkest area for which you anyway want to save some details, do a reading (say f5.6@1/15) and close a couple of stops (say you end up with f5.6@1/60), this should put your darkest spot in zone 3, the first density zone where details are caught on film
2) now you have to "develop for the highlights", which basically means finding the right development in order to save details in the highlights as well.  For this it is crucial that you understand the difference between "place" and "fall". In step 1 you correctly "place" the darkest area in zone 3, determining the right exposure set (f5.6@1/60), this means that all areas where you actually read f5.6@1/60 with your spot meter will "fall" in zone 5 (remember, your spot meter always read mid-grey), all areas where you read f5.6@1/250 will "fall" in zone 7 and all areas where you read f5.6@1/500 will fall in zone 8. Highlights are much less problematic to render than shadows but anyway I usually don't want anything meaningful in my frame to "fall" beyond zone 8. So, say you want to save the details in the shadows but save also the details in a beautiful cloud in the sky, you take a reading of the cloud so to know where it will fall with a standard development time. Say you read f5.6@1/500, this means it will fall in zone 8, still perfectly printable. Say you read f5.6@1/1000, it will fall in zone 9 respecting standard development time, so you under-develop to shrink a bit the density range and get the cloud in zone 8. Suppose it is a very dull day where you read f5.6@1/125 for the sky, in this case it will fall just in zone 6 and you could over-develop a bit to expand the density range and put the sky in zone 7.
The important bit to understand here is that development only controls the mid and especially the highlights, the shadows are not or very little affected by changes in the development process. This means that any shadow that is not recorded at exposure time is lost.
To really follow this method you should expose single sheets of film and register for each one the right development for the highlights (N, or N+1 or N-1,...). This is what Ansel Adams did. With a medium format camera like yours you could still achieve a good result using more backs.
All this is explained in great details in the Adams book "The Negative".
If you don't meter your highlights, you basically just "expose for the shadows" which is anyhow all you can do if you just have one back, at least you save your details there,  you can still somehow control your highlights during the print process.
Sorry for the long post, I hope it is of some help. Anyway again a great video of yours, keep shooting like a boss!

Thanks everyone for you kind comments, encouraging words and wisdom. Much appreciated. Great community here with a mixed combined level of knowlwdge and experience. Awesome!

I learned the ZS from Adams books and used it for 20years. My day job in the 70s was working at the National Geographic photo lab and a side gig teaching photography so I understand the technical side of things better than the average bear 😊

The simplest way to “Expose for the Shadows”  with a spot meter is do this test:  spot meter Zone 2 — first texture — shadow in a crosslit sunny scene.  Bracket by lowering  the ISO setting on the meter about three stops lower which changes the meter calibration value from 18% gray to Zone 2; e.g. set meter to 50 if using ISO 400 film.  Look at the shadow densities on the negatives and test prints then use the ISO of the frame with perfectly the Zone  0/ 1 / 2 exposed shadow from that point on.

Spot meters had not been invented when St. Ansel brought his grayscale stone tablet down from the mountain.  He was forced to meter of an 18% card.  The book then said to do the same bracket test adjusting the TRUE film speed and looking at neg and prints until the 0/1/2 shadows on them were optimal with just enough exposure to make the borders of the neg max. black on the print.

I quickly realized using a spot meter eliminated all the “interpret from Zone V” nonsense by simply changing the calibration value of the meter from 18%/Zone V to  the darker Zone 2 by lowering ISO.  It is also possible to shift calibration on most modern meters with a calibration adjustment of around -3 stops.

Zones ARE NOT f/stop they are tonal values on the print where 0 = max black obtained with min. enlarger exposure and 10 = white paper base WHICH  IS ONLY USED ON THE PRINT TO REPRODUCE THE SPECULAR HIGHLIGHTS.   Smooth white objects must be reproduced as Zone 9 light gray to preserve the PERCEPTION of 3D shape in the highlights.

For example shooting a white car the body of the car would be reproduced Zone 9 (light gray) and the paper base with no exposure / silver reproducing the Zone 10 reflections of the sun on the white hood.  When you wrap your head around that you’ll understand what St. Ansel was trying to teach the masses who would wash out the highlights and illusion of 3D on prints by using the paper base to represent the white hood, in the process killing the speculars that create the perception of 3D in a 2D rendering.  

Painters under stand this intutively.  Water color painting is like photo prints where the paper base must be reserved for specular reflections.  In oil and acrylic media dots of white paint are used (a trick that can be employed in photoshop to add fake 255 specular highlights in white objects reproduced at 245-250

With sheet film the EV range of the scene was used to know how long to develop the NEGATIVE to fit the range of the paper based on Adams’ goal of ALWAYS PRINTING ON #2 PAPER.  

That bespoke development based on scene lighting conditions isn’t practical on roll film but a reading the EV range from Z2 TO Z9 can be used to know in advance what Polycontrast filtering will be needed when printing, what I did most of the time using my color enlarger head to dial in the exact Yellow/Magenta CC values.

If scanning your negatives develop negatives from a clear crosslit sunny day to fit its range just as Adams defined his NORMAL development to match that sunny scene to  #2 grade paper.  As a baseline for the scanner find the development time which will fit a cross-lit sunny scene onto the histogram of the scan in Photoshop.  Then for lighting with less contrast — cloudy, overcast, etc. you can adjust the file from the scanner with a Levels or Curves adjustment.  

After getting into the habit of metering Zone 2 detail then Zone 9 non specular white highlights you will be able to realize the EV ranges just by the lighting and realize the exposures are about the same as predicted by the Sunny 16   (1/ISO @ f/16) rule and chart because the sun is consistent everywhere.  

I doubt Adams actually had to meter to determine exposure and development time but made a ritual out of it to teach those who didn’t yet have that experience and sell books.  He bracketed exposures and did a lot of dodging and burning on his prints to selectively change print value Zones after first using negative development to produce a full range from max. black to preserving the specular reflection on white objects.

It was a common practice to keep a yellow filter on the lens outdoors at all times because B&W is more sensitive to blue and near-UV than human vision so skies in photos without the filter would always wind up too light and overexposed compared to how they look by eye. Adams’ iconic photos of Yosemite with dark brooding skies making the highlighted rocks contrast more were the result of using a red, orange and yellow filters at capture.  Green, yellow and blue were used to make foliage appear lighter than it actually was.

Sent you a Sekonic? Nice guy. That’s a valuable meter.

I learned plenty about light !!! Thank you. RS. Canada

Zone System - multiple books (including all three of Ansel Adams) and websites later, with much experimentation, light meters, on camera and off. Conclusions - Ansel Adams was shooting large format, it records greater detail, it takes a singular shot in those lighting conditions and you develop that singular negative, try applying this to roll film and you are sunk, totally Titaniced, unless its the same scene on a grey day where the sky is a consistent grey. The zone system is a consistent sliding scale of the scene before you, you lighten the shadows, then you're lightening the sky as well, you darken the sky then you're darkening the shadows. The greater the light contrast in a scene the greater the chance of blowing out the sky and/or crushing the blacks. I think you've a better chance when shooting roll film by trying to average out your exposure by using a wider light meter setting across all shots on that roll.
Ansel Adams was a great photographer with a large format camera, but he was more an expert in darkroom jiggery-pokery than he was at producing a roll of well exposed 35mm film negatives.
Sorry if this is heresy and I've taken Ansel Adams' name in vain but I don't see how applying a singlular set of 'rules' to all types of photography and then scratching your head when it doesn't work makes much sense. Neither do I think Ansel Adams intended this to be the case, he kept well away from discussing roll film.

Best Zone System explanation on the net ever ! Congrats x 1000000000 !

Thank you for explaining clearly.
Really helps me to make sense of what I don’t understand yet. The first shot looks so much better than the lighting in the video suggested

For a complete understanding of the zone system, you would need to read “ The negative “ by Ansel Adams, or “ Way beyond monochrome “ Lambrecht, and Woodhouse. This is an excellent book which I think is the bible of monochrome photography. Both books delve into sensitometry, It just depends how far you want to go, and I think sometimes it’s best to go the fun way, and find out for yourself by trial and error.  After all many of Ansel Adams negatives required dodging and burning.

This has been the video I’ve been waiting for. It’s always difficult to read these systems designed for large format single development systems, but more modern chemicals and emulsions mean us medium format roll guys can take advantage more than we thought.

Hi, if your placing your exposure at zone 3 the problem is the highlight exposure could be 10 stops difference and you preferably want your highlights in zone 8 or 9, there is no zone 13, Graduated Filters solve this problem, Neutral Density, Tobbacco, anything that brings your highlight exposure down. You can't use them for everything but you can for situations where you have a clear distinction between highlight and shadow areas in say a landscape, seascape etc

Great work here on zone system. I will say you’re half way there. You’re right in exposing for the shadows and moving the zones from the metered to the zone you would like that tone placed in. The bit you’re missing Is to confirm the placement of your highlight. Black and white film has about 7 stops of dynamic range (prints about 5). If you’re highlight is 7 stops difference, no need for compensation. If it’s more than 7, less development is required. If it’s less than 7 and you want to add contrast, more development is required to push the highlight further.

Love the channel, remember the shadows develop in the first half of the time, so gives you half the time to adjust for your highlights. 10% or 20% normally does it for me on 8x10

Thank you for the video and sharing your experience! From my experience, I try to do as much as possible already during the shooting. When the sky is overcast but bright it is hard to get details in the clouds. A ND grade filter to darken the sky helps wonders. Yes, a yellow 1 could help as well but affetcts the complete photograph. BTW, for anyone shooting digital as well, there it is called "Expose To The Right (ETTR)" and refers to shifting the exposure histogram curve to the right during the shot and then fixing it in lightroom. Doing it in the digital world first helped me understanding it in film photography later.

I've spent years in the darkroom chasing my tail as it were. Older films had thicker emulsions that responded more readily to varying development times and dilution. You'll also find far better results using a "cold light" enlarger head if you're currently using a point light source. I switched to digital and have gone down the rabbit hole of digital printing. It's not better, just different and far less time consuming. I still keep all my old darkroom equipment in my attic just in case. And my old darkroom is now a woodshop. Another expensive pursuit. By the way, I appreciate the great quality of your videos, well thought out and edited.

You had the right idea on under developing, but you didn't also overexpose which goes hand in hand with that technique. When I look at your developed prints, those areas you metered in the shadows mostly end up black and the whole shot is overly contrasty.  The whole reason for doing this is this technique is to compensate for the already huge dynamic range  (contrast) between highlights and shadows.  You should have shift that HP5+ ISO400 down to ISO 200 or even ISO 100 (pulled) which would have overexposed your shots by 1 or 2 stops, then underdeveloped.   This would have given your shadows some detail and then by underdeveloping not overblown your highlights.

That was a great explain. That first one is a beaut, to me anyway. Glad I have a spot attachment for my Gossen LunasixF. Thank-you!

Great info. I recently saw an old video of an instructor recommending putting shadows in Zone 3 instead of 4 to get more texture and detail in shadows then reducing the development Time as to not blow out highlights. Then in post bring the shadows down to Zone 4. According to the instructor you'll get a lot more detail/texture in the shadows that way without blowing out the highlights

Definitely gonna give this a try excellent work

I was going to say what Marco said but he did a great job explaining it.  The key is to also meter the highlights and know where they fall and that determines development time.  Also using a developer that is good for this work.