Hard to focus 150mm f/4.5 on Mamiya 6

pixelatedscraps

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After returning from my trip to southern India last week, flush with excitement over the 9 rolls of Portra 160/400, 5 of Ektar, 1x Reala Ace, 1x expired Velvia, the couple of rolls of Ilford and TMAX 100, not to mention the 8 rolls of 135 I took for my girlfriend and I to share with the Minolta CLE (thanks Geert!) and XA2, I finally got all my negatives and slides back from the lab and scanned on my 9000F. The result?

A lukewarm, tepid selection: to say I was disappointed in myself would be a slight understatement. I used the 150mm lens about 75% of the time, either hanging out of the side of an 'auto' or for taking street shots as we walked through the streets of Pondicherry, Cochin and Allepey. The rest of the time was with the 50mm.

I would probably say, out of the 350+ photos I took on that trip, I had about 35 I would call keepers, well below what I would call my usual rate. Out of those 35, probably only about half of them were bang-on, in focus. Even though I had taken my time with it (wary of the difficulty focusing the 150 on the Mamiya 6), and had the lens & rangefinder calibrated before leaving, so many shots were out of focus it was quite depressing.


My eyes aren't perfect, and this is one of the first times for me stepping up beyond the 50mm focal length. My favorites were always 24mm-35mm up until this point, but I thought for candid photography, the 150mm (roughly a 110mm equivalent in 35mm terms: correct me if I'm wrong?) would be most effective. As it is, unless I get contacts, I can see myself having to train my eyes for a long time to use this lens effectively.

What are your experiences with focusing the 150mm on the Mamiya 6?
 
Ok so you did calibrate the camera and lens. That was going to be my first recommendation. The 150mm for the Mamiya 6 is an amazing lens, one of the sharpest I've ever seen. The only problem is, your camera and lens have to be calibrated to perfection to get amazing results with it. Are you sure yours was calibrated correctly? Just taking a repairers word for it isn't always the best option. You have to run tests.

Once the camera and lens are perfectly calibrated, the second problem is actually focusing the thing. My eyes are perfect and I still make sure a few times over that it is in perfect focus. I work primarily from a tripod and am not rushed, so I can make sure it is in perfect focus. I couldn't imagine using this lens for candid photography of people. I would find it almost impossible to get a quick shot in focus shooting close at a wide aperture. The 75mm would be much better for this, or an SLR.

Also, shooting at wide apertures with this lens is going to result in disappointment unless, again, that your camera and lens are perfectly in tune. Depth of field will make up for some errors in focusing, but to me that ruins the whole point of having a telephoto lens half to time, for shallow depth of field!

In the end what I would recommend for you is running tests and then maybe only using this lens for landscapes, and or on a tripod or situations where you can take your time focusing. An SLR would be much better for those situations. But as they say, 'practice makes perfect!'
 
Thanks for taking the time to reply Brian, you've pretty much said everything that's been going through my mind--only more coherently!

I have been toying with going back to SLRs, actually. I used to own a Hasselblad 500 C/M with a bunch of lenses but it was simply too slow (or I was) for my kind of shooting. Unfortunately, every holiday I go on, I want that big 6x6 square and as far as I know there is no 6x6 or 6x7 camera, either RF or SLR (not a fan of TLRs), with interchangeable lenses and fairly light and portable--the Pentax 67 is simply out of the question here.

I took the lens and body to the official Mamiya agent here in Hong Kong. In fact, I took all three lenses along, and was surprised when I got an invoice for only $75, including three extra Mamiya lens caps. Maybe they didn't understand what I meant by 'calibrate rangefinder to lens'?

Tests...dammit, I wish it didn't have to resort to that. I'm crap like that, impatient: I just want my things to work and then whine like a 5 yr-old when they don't.

So, a tripod, a method of measuring distance in meters and...a subject to shoot, and...a few rolls of film and a notebook, or am I missing anything?
 
As for tests, the best way to do it is to get a ground glass, cut it down to fit the square opening on the back, put the camera on bulb, open the back, using a locking cable release, release the shutter, lock the cable release and focus the lens in the viewfinder then see if its in focus on the ground glass.

Too much? I thought so. An easier method is to simply shoot film! Use a tripod and shoot with the lens at f/4.5 and focus on something close, and well defined and two-dimensional, like a door or wall with detail (bricks). Vertical lines are super easy to focus on, I recommend those. Start at something at like 7'. Then shoot some tests wide open at something around 15' and then 20' and lastly infinity. It's important to make sure you're shooting wide open so that depth of field doesn't cover up and focusing errors. Take your time and make sure that you're in perfect focus! Process your film and look at it with a loupe on the light table. If all subjects you focused on are in perfect focus from near to far then you're good to go! If not you need re-calibration.
 
Wouldn't it be sufficient to just test for the shortest distance ? For longer distances, there's more DOF anyway, so it's harder to judge then if calibration is correct.
Or is it possible that a lens is well calibrated for the shortest distance, and not well calibrated for infinity (to take the extremes) ?

Stefan
 
Stefan, yes you could just test the closest focus and infinity, but atleast those two. Yes it is possible that a rangefinder/lens combo could be great up close but not at infinity and vice versa. Tests are the only way to find out.
 
Brian: you're right, that first suggestion was completely over my head. I'll be getting out the tripod and doing some testing. I'll post back with the results.

Thanks again!
 
I have the Mamiya 6 since about a half a year. Indeed - the 150 is not easy to focus. After I got back from my vacation I could only say that I probably got lucky as most of my shots with 150 are in focus (though only part of them was shot wide open).

I would suggest - try to find some magnifier (what about those 1.4x for Leica? anybody has a better idea?) that can be attached to the viewfinder, put the camera on a tripod and try to focus first without and than with the magnifier. Do you see the focus where it should be? The expose the shot and see what comes out.

I would say more training, but after 350 shots this kind of comment is probably obsolete ...

If you look at those miss focused shots of yours - do you see any systematical tendency to front focus or back focus? It is not a proof, but it could point towards wrong calibration of the rangefinder.

Should you come to a conclusion that the rangefinder is not properly calibrated, than consider sending the camera to Mamiya - they are able to test whether everything is as it should be for rather little money (I read that somewhere on their website).

good luck - the 150 is worth the hassle.
 
Actually, before I went away to India, I sent the Mamiya (and all three lenses) to Mamiya with instructions to calibrate the rangefinder. I will go through my photos again and check to see if it was front focus or back focusing issues. If there is a pattern there it could also be down to my style of shooting, or at least my style of not leaving the focus ring on infinity after every shot/roll.

That said, in order to get to the bottom of this, I need to do some proper testing. Though I've been a very happy Mamiya 6 + 50/4 user for a few years now, it was my first time using the 150, and I don't think going on a short two week trip shooting every man, woman and child (and their chicken) is a good way to test out my crummy hand to eye coordination!

Will post back with results
 
As others have said, Have your lenses matched to your Mamiya 6.

I took my Mamiya 6 and all lenses in to a Mamiye Service shop and had them do the following:

1. Check and adjust the rangefinder as required.

2. Match all 3 lenses to this body. This is done by adding shims to the lens mount on the lens. Once this is done, all your lenses will focus spot on.

I had this done a long time ago and I bought my Mamiya 6 new with the 75, and 150. Later picked up an as new 50mm. All images taken with all lenses are sharp and spot on in focus, as long as I am careful and take my time to insure I am on focus. Especially with the 150mm. I have some prints from this lens at the waterfront / docks that I had enlarged 48" x 48" and you can stand 1 foot away and it is still sharp.

If you do as I have done, you won't have any focus problems with the 150.

Regards

Akitadog
 
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