2.17.2024

I think it's important to test the gear you want to end up using. The Voigtlander 75mm tests showed me that the focus calibration of my newest rangefinder camera could be better. It's a demanding lens....

Just a few blocks from my house the Barton Springs Nursery is a wonderful place
to browse through landscaping and outdoor furniture or just to sit and soak up
the birdsongs, the fresh air and the peacefulness of the place. Or to test a camera.

We are incredibly fortunate to live in a wonderful neighborhood. We're just around the corner from my favorite daily coffee shop, Trianon, and my favorite gardening store, Barton Springs Nursery. The nursery is beautifully laid out, has only premium tools, furniture, plants and materials and, most important to me, it's a very welcoming place with lots of chairs, tables and benches. They have coffee in the main office (which is a beautifully restored house) and are happy to have people drop by, grab a cup and sit in the middle of a couple acres of shade trees, surrounded by all sorts of calming landscaping. 

I had occasion to go there yesterday to pick up a gift card for a very close friend who is a committed gardener. And, as usual, I took along a camera. The one I've been torturing myself with most of this week is the Leica M-E 240. I've been re-learning that fully mechanical rangefinder cameras are more work than conventional cameras. Not just in the shooting but also in the calibration. 

I was happy with the calibration as it came from the retailer and I didn't notice much of a back focus when using shorter lenses but half way into Wednesday I put a 75mm f1.9 lens on the camera and started taking test shots with the aperture set to wide open, around the office. I noticed the lens back focusing. Stuff I focused on was less sharp than stuff a couple inches back. A fast, medium telephoto lens is just at the edge of the envelope for mechanical rangefinders which makes good calibration essential. Especially if you anticipate using the camera and a fast portrait lens to make....portraits. Especially head and shoulders portrait in which you'd want the eyes of the subject to be critically sharp. 

The first step in any camera calibration is to make sure that it's actually the rangefinder and not a lens that's out of whack. I paid more attention and tried a 50mm at f2.0 and a 90mm at f2.8 and this time around I could see a difference. I pulled a second body out of the cabinet and repeated the tests on that camera. All the lenses were equally well behaved so....of course... the fault lay with the new camera. 

I re-calibrate rangefinders in small increments and then use a distant target to make sure I've nailed infinity focus. Theoretically the optical/mechanical machinery is linear so every other focus distance should fall into line. But I find that fast lenses used close, near minimum focus distance, and wide open, can show you more easily perceptible over and under focus. As long as you realize that depth of field falls one third in front and two thirds behind the actual plane of sharp focus. If you expect equal zones of sharp focus on both sides of the plane of focus you will have over-compensated by a bit. I try to make sure I don't let that focusing phenomenon color my calibration efforts. 

Once I'm pretty certain I've got it all wired up correctly I want to take the camera and most demanding lens out for a spin and photograph stuff in the real world, at distances from the close focus limit all the way out to infinity and then I want to look at the results at 100% on a large, high resolution monitor. It's so much more revealing on a 27 inch retina screen than on the antiquated rear screen of a twelve year old camera model. 

As I walked around the gardens I photographed different subjects and I was amazed at how much more I have to pay attention to exactly where I've set the rangefinder rectangles to get exact focus as compared to the ease of autofocus. Over the course of the day I discovered that there is variation depending on where in the coincident patches your point of focus lies. 

When you are out walking around testing your camera and lens there is a tendency to shoot raw and then to look at a file review on the back monitor. While I've already cautioned that older LCDs aren't really high enough resolution to tell you much you also have to consider that the embedded review files in raw captures (as opposed to raw+Jpeg) are also lower resolution than a captured Jpeg which delivers a full resolution preview on the camera's rear screen. If you only shoot raw and depend on the perception delivered by the rear screen of a camera you'll drive yourself a bit crazy because you'll always be seeing a lower res image and if you punch in to, say, 10X the resulting magnified image will seem a bit blurry.

You can test this yourself by shooting a test target with your camera set to raw and then shooting the same target with a full sized Jpeg and then comparing the results at full magnification on the rear screen. The differences are quite apparent. 

I guess that's why I don't make any final judgments on image sharpness until I can get in front of the office computer, open up PhotoShop and have a good look. 

With all this in mind I resisted shooting raw files yesterday and set the camera to large/fine Jpeg. The resulting files were great and the focus, when I aimed correctly, was good even with the 75mm lens used at f1.9 and working at close distances. The focus throw on that lens is so short it makes fine-tuning focus while shooting a bit tricky. But all in all I'm happy with the results and have more appreciation for how good a performer that 75mm is. 

As a final test I headed over to South Congress Ave. I had two or three goals. One was to have a lovely afternoon cortado at Jo's Coffee and to spend a bit of time watching the stream of tourists walking by. Another goal was to revisit the Maufrais hat shop and see if I felt ready to splash out for a Stetson Open Road hat (I'm still not at all ready to fork over nearly $300 for any hat!!!). And finally, I was looking for the perfect birthday card for my closest friend. Which I did find. 

While walking along S. Congress Ave. I took photos of signs because it an almost cheating method of judging sharpness. But I found other things to photograph as well. Now I'm 100% confident to use my new camera. The experience also spurred me to evaluate the two other 240s in the inventory. Oddly, both of them are perfect. Go figure. 




Focus on the second chair.


Magnolia Cafes have been in Austin for well over 30 years. A home grown 
restaurant that functions as Austin's version of a diner. But with an 
emphasis on breakfast. Omelettes, pancakes, egg dishes and lots and lots 
of coffee. But if you are hungry for other fare it's all on the menu. 

I knew I nailed my calibration when I got home and took at look at the 
bow on the hat. That's the exact spot I was focused on...


the edges of type are great focus targets. 






Seen at the old barber shop on S. Congress. Nice rules to live by.
Well, except for the "horsin' around", I'd probably mess up on that one. 

I see this every time I'm on S. Congress Ave. It's on the way to my favorite 
parking space. The wall texture was my actual target. 

Getting your camera set up and accurate before using it for critical work is just common sense.
Amazing how many people take camera function and operation on faith.
I prefer to know what I'm getting into. 

You should too. 

And, I am now of the belief that rangefinder cameras are not a good choice as 
first camera for a beginner photographer. They are also more of a specialty camera than a 
camera for various commercial shoots. Nice to have but a bit 
eccentric. With a limited range of applications.  
I'm over the hump of having to press every camera and 
lens into the "work paradigm." Some things I buy for nostalgia's sake or
for the Quixotic nature of their operation. If you can have only one
camera it's probably wise to find something with a wider use envelope than
an M series Leica. 

Just sayin"





16 comments:

TMJ said...

One of the fun things about rangefinder focussing is that it doesn't know whether your lens aperture is f1.4 or f16.

Kirk, Photographer/Writer said...

So True. And you don't know by looking through the finder either....

Biro said...

Yeah, but manual focusing in low light is pretty darn easy - as long as you can see the rangefinder box.

lsumners said...

Do you use magnifying focus with manual lens?

Kirk, Photographer/Writer said...

Biro, Much easier than focusing a mirrorless camera in very low light. That's for sure.

My M's are not going anywhere....

Kirk, Photographer/Writer said...

isumners, I don't use magnifying focus aids with the rangefinder cameras. With mirrorless cameras? Yes.

adam said...

signs are what I use when zone focusing, though I eyeball the "1.5m away part"

SW Rick said...

Buy the hat! You are not about to spend money on a Ferrari, so enjoy some of life's little pleasures while you can.

Rick

Kirk, Photographer/Writer said...

B. says if I want a Ferrari I'll have to part with the Bentley GT Speed. Not sure it's worth it. And the hat? Seven and five eighths. I'm sure one of my dedicated readers like Rick already has one heading my way via Fedex. Thanks!

EdB said...

I second the motion to just buy the hat. I've had mine since 1982 and it's still in great shape. Make sure to get a hat brush and have them show you how to steam the hat from time to time.

Greg Heins said...

I am reminded of a photographer friend who asked me a million years ago if I had ever tested to make sure that my view camera focusing screen was in the exact same plane as my film holders. I told him that this was the point of buying a Swiss view camera. "Of course. Have you tested?" I had not, I did, and then I shimmed my focusing screen to bring it to the proper plane. Did it make a difference? Yes, indeed.
And by the way, the hat makes the man. Although usually you can only wear the hat when you're leaving the house by yourself.

Kirk, Photographer/Writer said...

Hi Greg. Good to hear I am not alone. I remember buying two Leica M6 cameras from an authorized dealer, brand new. This was in the mid to late 1990s. Both had completely uncalibrated rangefinders. How the cameras ever made it out of the factory is beyond me. As Ronald Reagan once said: "Trust but verify."

Travis said...

I have nothing to add except to echo the others: buy the damn hat. :) Can't wait to see it in those mirror selfies...

mikepeters said...

Back in the 80's and 90's when I shot with Leica M4P's, I needed four bodies to have two working at any given time. Before every shoot I would put each camera on a tripond without the back door, open the shutter and put a ground glass with a good loupe on the film rails and focus on a bold black vertical line 6 feet away on my wall. I'd then check the rangefinder to see if it would agree. And then I would repeat in the opposite direction, using the rangefinder and then checking the ground glass. If they were consistently in agreement, I'd put it, ever so gently into my bag for the day. If not, I'd make an appointment with my very good friends in Rockleigh NJ and drive up. The got to know me well enough to do the collimation while I waited.

The rangefinder mechanism in the M4P seemed very susceptible to going awry with the least amount of provocation. The 75mm Summilux was extremely difficult, and the 135 f2.8 the least reliable as there was the additional issue of the goggles being knocked off kilter.

Fun days indeed.

Ken Tanaka said...

If I drank as much coffee as you do my rangefinders would NEVER seem properly calibrated! 😂
Seriously, though, I’ve never considered that this to be a DIY operation. But after reading this I found an instructional video showing that horizontal adjustments can “easily” be made (if you’ve not ingested too much coffee). So thanks for this!
(Unfortunately my right eye is barely good enough to use a rangefinder at all any more, regardless of calibration. My OD tells me it will need some professional calibration soon.)

- Ken -

Kirk, Photographer/Writer said...

Ken, I actually ingest only two cups of medium roast coffee (8 ounces each) during the course of a typical day. Honest!

And I try to do my rangefinder calibrations with the camera on a stout tripod. So far my hands are steady enough...