Mamiya 645 focus issue?

Bell

Bell

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Matt
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Ok so I am stumped here and in need of help.

I've developed my first batch of portra 160, all landscape images with the mamiya 645 and 45mm f2.8 lens.
However, all shots are "out of focus" and appear very soft beyond about 3m into the scene. It's as though they were all shot at f2.8 but I know for fact I set f11.
Now, I went to have a play with the setup without film to see if I could find anything wrong and saw that the A/M switch was set to Auto. I guess this had been accidentally moved while setting up at some point but will this affect the final image if the shutter is set to f11?
I notice in A mode, the blades don't close down when adjusting the f stop, but in M mode they are moving fine.
Is this my problem?
 
Bell said:
Ok so I am stumped here and in need of help.

I've developed my first batch of portra 160, all landscape images with the mamiya 645 and 45mm f2.8 lens.
However, all shots are "out of focus" and appear very soft beyond about 3m into the scene. It's as though they were all shot at f2.8 but I know for fact I set f11.
Now, I went to have a play with the setup without film to see if I could find anything wrong and saw that the A/M switch was set to Auto. I guess this had been accidentally moved while setting up at some point but will this affect the final image if the shutter is set to f11?
I notice in A mode, the blades don't close down when adjusting the f stop, but in M mode they are moving fine.
Is this my problem?
Click to expand...

A is the correct position for taking a photo. The M position stops the lens down to your selected f stop so you can get an idea of DOF.
 
Ok thanks. So it seems I have a focusing issue then.
I'm using the scales on the lens to focus so that f11 is on infinity focus marker yet they look more like they were shot at f2.8.
But I've metered at f11 and I'm happy with the exposure on the negatives.
 
Ok on focusing, do you not have a waist level finder or a prism to check focus with?
Which lens are you using?
 
I'm using a metered prism and looks fine at setup.
It's the Sekor 45mm 2.8 lens
 
Bell said:
I'm using the scales on the lens to focus so that f11 is on infinity focus marker
Click to expand...

OK on that . What is your f stop? is it f11? what distance was your point of focus....infinity? or are you zone focusing?
I will get my 45mm lens out and try to reproduce what you have done on my Pro TL.....
 
Is this a new lens or have you used it before with successful results? Does it have a macro setting that's been activated?
 
Cannyekerslike said:
OK on that . What is your f stop? is it f11? what distance was your point of focus....infinity? or are you zone focusing?
I will get my 45mm lens out and try to reproduce what you have done on my Pro TL.....
Click to expand...
Yes, f11 point of focus is approx 2.75 m into scene, f11 gives 1.3m to infinity on the scale.
It's a 645 pro for reference. Thanks
 
FujiLove said:
Is this a new lens or have you used it before with successful results? Does it have a macro setting that's been activated?
Click to expand...
This is why I think I may have problems. It's the first results from camera and lens
 
Might get a roll of B&W film through it and experiment with different techniques.
 
OK Matt,
So putting my 45mm lens on the camera and setting to f11 and placing infinity mark over f11 on the right of the point of focus gives me a depth of field of 2 meters to infinity on the scale and the point of focus is 4 meters on the scale.
Stopping the lens down, moving from A to M, it would appear that what I can see would be about right for what the scale indicates.
I think we may have different lenses, mine is an N.
I would go along with you putting a roll through and focus on different points say 1, 2, 3, 5 and 10 meters or 1, 2, 5, 10 and infinity and try three different f stops at each distance, that would give you 15 shots and the end of the film. Put the camera on a tripod to eliminate any wobble. If it comes out the same as the first roll, out of focus, then it will need a service, probably the mirror that needs adjusting.
I had mine serviced at the beginning of last year and it came back like a new camera. Great cameras from my point of view, handle just like an SLR with a motor drive fitted which provides a meaty grip and a metered finder. I use mine for Slide and B&W, two backs so just a quick swap from one film to another.
Lets us know how you get on and perhaps post a photo off your first roll.
 
Ok great, thanks for taking the time to go over that.
I'll order a roll of ilford and try it.
 
Did you shoot hand held. Could it be a case of slow shutter speeds and camera shake ?
 
Tripod mounted for all, shutter was no lower than 1/30th on any shot and conditions were very little wind. Never used mirror lock up though.
 
Bell said:
Yes, f11 point of focus is approx 2.75 m into scene, f11 gives 1.3m to infinity on the scale.
It's a 645 pro for reference. Thanks
Click to expand...

Cannyekerslike said:
So putting my 45mm lens on the camera and setting to f11 and placing infinity mark over f11 on the right of the point of focus gives me a depth of field of 2 meters to infinity on the scale and the point of focus is 4 meters on the scale.
Click to expand...

I've never used a Mamiya 645, so this is purely from a position of ignorance, but I find the above two quotes appear to show a significant difference that I'd like to see explained.

If it really is being focused by scale, I don't see how any misalignment of mirror (or focusing screen) could have any effect, as neither should be being used (in these circumstances) for focusing.

Personally, I'f like to see the results of the oblique ruler test - lay out a measure on the ground, focus on a known part and then see what the depth of field is by inspection of the results.

DepthOfFieldExample.jpg
 
StephenM said:
I find the above two quotes appear to show a significant difference that I'd like to see explained.
Click to expand...

There are three 45mm lenses for the Mamiya 645 system that I know of that are manual focus.. I was quoting the readings off the DOF scale on the lens and I think that Matt was too. As I wrote in post 15 I think we were using different lenses as in different issues.
 
Would need to see the photographs and maybe that would give us a better clue. Matt I cannot understand why you have not put up examples as without everyone is clutching at straws.
 
medwaygreen said:
Would need to see the photographs and maybe that would give us a better clue. Matt I cannot understand why you have not put up examples as without everyone is clutching at straws.
Click to expand...
I appreciate that, I have only just had chance to get them uploaded last night.
I will post a few shots later this morning.
I also found a phone app last night (no idea how accurate it will be) but it says that at f11, 45mm lens, with focus on 2.75m as I was, that the focus range is from 1.6m to 9.3m.
Where as Hyperfocal distance at f11 it says is 3.88m in order to focus to infinity.
 
Bell said:
Ok thanks. So it seems I have a focusing issue then.
I'm using the scales on the lens to focus so that f11 is on infinity focus marker yet they look more like they were shot at f2.8.
But I've metered at f11 and I'm happy with the exposure on the negatives.
Click to expand...

Hi
You can't trust every lens when it's set on the infinity marker, only use the sharpest image in the viewfinder, you'd think the depth of field would compensate but it didn't on one lens I had........In theory what you see for sharpness in the viewfinder should be the same sharp image that is projected on to the film.
I have some lenses that go past infinity for sharpness and also have done tests on some old lenses where I've taken shots at different distances comparing distance on the lens and what you see in the viewfinder and they don't match.
 
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excalibur2 said:
Hi
You can't trust every lens when it's set on the infinity marker, only use the sharpest image in the viewfinder, you'd think the depth of field would compensate but it didn't on one lens I had........In theory what you see for sharpness in the viewfinder should be the same sharp image that is projected on to the film.
I have some lenses that go past infinity for sharpness and also have done tests on some old lenses where I've taken shots at different distances comparing distance on the lens and what you see in the viewfinder and they don't match.
Click to expand...
Appreciate that, the image in the viewfinder appeared sharp at the time.
I have put a roll of B&W in and am going to do a series of tests later today just for my own benefit to see if it's just my focusing error.
 
Bell said:
Appreciate that, the image in the viewfinder appeared sharp at the time.
I have put a roll of B&W in and am going to do a series of tests later today just for my own benefit to see if it's just my focusing error.
Click to expand...

Well I would suggest different distances on subjects (using a tripod)) and go from there when you see the results.
 
excalibur2 said:
Well I would suggest different distances on subjects (using a tripod)) and go from there when you see the results.
Click to expand...
Thanks, yes to make it a decent test I had planned on using Tripod, in A mode, mirror lock up on, delay timer on.
 
I take it the focus screen in the body is sitting flat along with the film holder? Have you got another lens you could use to see if it's an issue specifically with the 45mm?
 
stevelmx5 said:
I take it the focus screen in the body is sitting flat along with the film holder? Have you got another lens you could use to see if it's an issue specifically with the 45mm?
Click to expand...
To my eye it looks flat and there's no movement on it, also checked the mirror, there's no play in it and can't see any internal damage on the bracket or support.
I've used two different backs with different inserts on recent shoots and both give same results.
My 70mm is currently out of action due to seized aperture blades. I'm ordering a 150mm soon so if these tests are inconclusive I will try that as well. Cheers.
 
medwaygreen said:
Matt, are these three shots taken with the same settings,aperture, speed Asa speed etc.?
Click to expand...
All f11, all metered for Portra 160 at 160 asa , shutter speeds; top and middle were 1/125, bottom was 1/15
 
"Appreciate that, the image in the viewfinder appeared sharp at the time."

This is key to the problem,if it looked sharp at the time of taking then it would appear that there is either a lens problem or a film platform problem.

Not having to go into CLA cost,it may be better to post the lens to a member who can run of a film and post the results from their body,that will element the lens,then you can concentrated on the body.

If you run another film and it is the same you are nowhere.

Best of luck.

Richard.
 
Bell said:
All f11, all metered for Portra 160 at 160 asa , shutter speeds; top and middle were 1/125, bottom was 1/15
Click to expand...

Just seen this 1/15 are you sure your speeds are accurate?
 
Not a bad shout, I will see what comes of this test.
I'm almost convinced after seeing what the Hyperfocal app kicked out, that I'm just being thick and setting focus wrong.
Bad workmen blame their tools and all that!
 
If the image is sharp in the viewfinder I'm not sure it could be the lens as you're looking straight through it so you'd never get a sharp image anywhere? When set to Manual, do you see the aperture blades stop down evenly when you adjust the aperture? When on auto you're focussing at F2.8 so it could be an issue when the lens auto stops down to take the shot.
 
medwaygreen said:
Just seen this 1/15 are you sure your speeds are accurate?
Click to expand...
Hadn't thought to check as I'm happy with exposure. Don't see how this would affect near/far focus if tripod mounted though?
 
stevelmx5 said:
If the image is sharp in the viewfinder I'm not sure it could be the lens as you're looking straight through it so you'd never get a sharp image anywhere? When set to Manual, do you see the aperture blades stop down evenly when you adjust the aperture? When on auto you're focussing at F2.8 so it could be an issue when the lens auto stops down to take the shot.
Click to expand...
Yes, tried that, happy with movement. I checked it soon as it arrived due to the 70mm having similar problems.
 
stevelmx5 said:
If the image is sharp in the viewfinder I'm not sure it could be the lens as you're looking straight through it so you'd never get a sharp image anywhere? When set to Manual, do you see the aperture blades stop down evenly when you adjust the aperture? When on auto you're focussing at F2.8 so it could be an issue when the lens auto stops down to take the shot.
Click to expand...

True Steve for OOF but it's only when you see the results on the screen or say A4 print will you see how good the lens is...esp if cropped. Good point if the lens isn't stopping down.
 
The online DoFMaster (http://www.dofmaster.com/dofjs.html) suggests 1.8m to 7m DoF for 6x4.5/45mm/f11/2.75m with a 0.045 circle of confusion.

Given that, I'm not sure there's a problem at all, except maybe on the lens markings. The stuff in the foreground is sharp, infinity isn't.
 
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