Canon P - Photo Scans Keep Coming Back Blurry/Out-of-focus

[grain elevator]

That's the problem. I feel like NOTHING is in focus. I decided to whip out my old V600 and scan some of the negatives (the blurry photos that started all of this were from a local shop). No increase in sharpness doing my own scans.

In pic no. 1, the left speaker is in focus. No. 2 has a little motion blur. In no. 3 the stuff on the far right is in focus. Where did you focus? Well it's a academic question now, as you've already altered the rf calibration.

 

[flavio81]

Guys I am absolutely stumped.

I bought a nice digital microscope to view the image on the piece of tape over the film rails. I set the camera to wide open. I focused on a focus calibration chart about a meter away. I set camera to bulb, opened the shutter. I used the digital microscope to view the image on the piece of tape and got it so sharp. I then looked through the viewfinder and adjusted the rangefinder until the images lined up. Took the camera outside to test infinity and it was wayyyyyyy off. HOW IS THIS POSSIBLE?!

Camera tech here, let me help.

First, if you can afford a digital microscope you can also afford a spare focusing screen, it can be from any 35mm SLR. Use a focusing screen instead of the tape, it's more precise.

Then, you need to test the infinity of the LENS. Set the lens to infinity, focus to a really distant (at least a kilometer away or more!!) object like a landscape, and check the image that is produced on the film rails (using the focusing screen).

If it is not completely sharp, then there are two possiblitiies:

a. Your lens' infinity stop is off
b. The position of the lens mount is off (requires shimming).

(a) can easily be confirmed by trying a different lens. And if you only have ONE lens, then (b) doesn't matter for now, you can just have a technician recalibrate the lens infinity stop at, or you can re-calibrate the rangefinder to compensate a bit.

But let's assume the image is sharp when the lens is set to infinity.

Now, check the viewfinder. At infinity, looking to a really distant object, the image should align perfectly. More importantly, it should align perfectly on the horizontal axis. If it's vertically a little off, that's of no concern as far as focusing accuracy is concerned.

There should be one adjustment screw that allow you to move the horizontal adjustment so it looks correctly at infinity.

Now, to make a really GOOD work, after this adjustment, you should also focus at an object exactly at 1 meter on the ground glass and the rangefinder should align just fine as well. If it doesn't, on many cameras there is a way to correct the rangefinder for near focus too. The near-focus and infinity-focus rangefinder adjustments interact. I don't know what's the process for your Canon rangefinder. On many russian cameras, for example, the rangefinder coupling to the lens is a keel-shaped thing that can be rotated with pliers, this allows the near focus to be corrected.

 

[Huss]

Calibrating at 1m should also work, if you're working by a ground glass image. Is your tape perfectly flat? I suspect actual ground glass would be better. Make sure it rests on the film rails, not on the rails for the pressure plate.

You can do it the easiest, simplest, quickest and most reliable way - by calibrating at infinity.

Or you can get a piece of ground glass, aim at something 1m away, and drive yourself insane.

 

[Don_ih]

Or you can get a piece of ground glass, aim at something 1m away, and drive yourself insane.

You and I agree on that.

 

[250swb]

Pretty rookie question, but when I'm focusing at infinity f/1.4 should I have my lens indicator pointing at the infinity symbol or at 1.4?

I've said a long way back on page one that you will not get a perfectly crisp sharp image at f/1.4. So if you are testing at f/1.4 and judging your results based on the lens being wide open you are either compounding any problems with the rangefinder or it is the entirety of the problem you think you have. Nice as they are the Canon 50mm f/1.4 isn't great wide open, it isn't a Summilux, people buy it for the dreaminess at f/1.4 not for ultimate sharpness.

 

[reddesert]

There he was asking about the difference between the focus mark and the DOF scale. The focus distance is the focus distance no matter what f-stop you are at.

OP, I want to respectfully suggest that you should master the camera manual (which covers the DOF scale, etc) before doing anything like rangefinder adjustments, which usually are the realm of a repair tech or very experienced user. Now you must calibrate the rangefinder at infinity to undo the adjustments you made before proceeding any further. Or get a repair person to do it.

 

[grain elevator]

You can do it the easiest, simplest, quickest and most reliable way - by calibrating at infinity.

Or you can get a piece of ground glass, aim at something 1m away, and drive yourself insane.

I've done it at one meter and I'm still perfectly sane, the sanest person I know in fact, my therapist agrees, are you listening at all? The sanest I tells you!
Anyway the usual infinity method relies on the infinite stop of the lens being accurate. For that you don't need a ground glass. If you're uncertain about that and use a ground glass, might as well work at a closer distance, where you can rock focus back and forth to find perfect focus as you would with a SLR. It's in no way harder than at infinity.

 

[bdial]

learncamerarepair.com has a couple of Canon rangefinder repair manuals. There might be a recommended procedure.
https://learncamerarepair.com/productlist.php?category=2&secondary=1 (page down quite a way to get to the Canon 7/P manual)

 

[brbo]

Anyway the usual infinity method relies on the infinite stop of the lens being accurate.

Yes, infinity stop needs to be accurate. But that is not the only thing. Flange distance out of spec, not screwing lens into proper position...

For that you don't need a ground glass. If you're uncertain about that and use a ground glass, might as well work at a closer distance, where you can rock focus back and forth to find perfect focus as you would with a SLR. It's in no way harder than at infinity.

Adjusting at infinity is the same as at close distance. Except, when it isn't (as flavio81 has said already). There might be a separate close range adjustment needed in OP's camera. Leicas have infinity and close range adjustments.
Don't know how similar Canon P and 7 are, but service manual for 7 describes both infinity and close adjustments (P manual sadly doesn't deal with rangefinder adjustments at all).

 

[grat]

How to Calibrate a Canon P Rangefinder (in my case, for use with Soviet lenses) - by Cameradactyl (Ethan)

I am a fan of quirky old soviet cameras. I have had, loved, and broken a few Zorki 4 cameras over the years, and I love their lenses. I own Jupiter 8, 9 and 12 lenses (50mm f2, 85mm f2, and 35mm f2.8). I use the 35mm for more than 80% of what I shoot, but the Zorki viewfinder only really...

www.35mmc.com