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12-21-2010, 12:13 PM   #1
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Having no infinity focus on manual lens?

How much of a problem would this be?

I think it'll probably be not so good with landscape, but how about portrait (bokeh)... I know macro won't have any problem, but what problem can arise without infinity focus?

thanks.

Asuming the lens we're talking about is a 28mm or 50mm prime manual.

12-21-2010, 12:15 PM   #2
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should be acceptable for portrait (and probably macro work if it's capable) the 50 length would be more suitable for portrait (and of course you'll want to shoot close to wide open)
landscapes are out
What lens?
12-21-2010, 12:19 PM   #3
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Basically, you would not be able to shoot anything past the furthest distance on the scale. So that doesn't really rule out landscapes, it just rules out distant landscapes. I see no problem with portraits and macro work. Unless someone is giving you this lens for free, no infinity focus is a deal breaker for me.
12-21-2010, 12:59 PM   #4
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If you use Hyperfocal focus I would think this should not be a problem, but I've never tried.

Can anyone confirm otherwise?

12-21-2010, 01:06 PM   #5
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QuoteOriginally posted by lats Quote
If you use Hyperfocal focus I would think this should not be a problem, but I've never tried.

Can anyone confirm otherwise?
I've also heard about Hyperfocal focus... gonna go read it up... i saw some picture (landscape) of hyperfocal focus, it actually doesn't look bad in a pinch.
12-21-2010, 01:25 PM   #6
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Lenses are normally able to get to infinity, why your is unable to reach it? Are you trying to use lens of a different mount with some sort of adapter? Or the lens is defective in some way?

A few millimeters of extension applied to a 28mm lens will effectively turn it into a macro-only lens. Just think that 28mm of extension will focus the lens close enough to take 1:1 (life size) shots with the lens itself set at infinity.

If the problem is really marginal you could have sharp enough photos at infinity by setting a small aperture, such as f/8-11 or more.
12-21-2010, 01:33 PM   #7
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QuoteOriginally posted by Huck Finn Quote
Lenses are normally able to get to infinity, why your is unable to reach it? Are you trying to use lens of a different mount with some sort of adapter? Or the lens is defective in some way?

A few millimeters of extension applied to a 28mm lens will effectively turn it into a macro-only lens. Just think that 28mm of extension will focus the lens close enough to take 1:1 (life size) shots with the lens itself set at infinity.

If the problem is really marginal you could have sharp enough photos at infinity by setting a small aperture, such as f/8-11 or more.
sounds like use of an adapter and another mount, to me, there are lots of adapters that mention you can't focus to infinity , perhaps the op has some Nikon lenses most adapters mention they won't infinity focus
12-21-2010, 01:37 PM   #8
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QuoteOriginally posted by eddie1960 Quote
sounds like use of an adapter and another mount, to me, ...
Probably so, yes. Let's wait and see.

12-21-2010, 03:15 PM   #9
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QuoteOriginally posted by Huck Finn Quote
Lenses are normally able to get to infinity, why your is unable to reach it? Are you trying to use lens of a different mount with some sort of adapter? Or the lens is defective in some way?

A few millimeters of extension applied to a 28mm lens will effectively turn it into a macro-only lens. Just think that 28mm of extension will focus the lens close enough to take 1:1 (life size) shots with the lens itself set at infinity.

If the problem is really marginal you could have sharp enough photos at infinity by setting a small aperture, such as f/8-11 or more.
yep, I'm using a different mount lens that's not quite compatible (the flanged distance is 1mm longer then the lens is suppose to be use).
12-21-2010, 03:45 PM   #10
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QuoteOriginally posted by clockwork247 Quote
yep, I'm using a different mount lens that's not quite compatible (the flanged distance is 1mm longer then the lens is suppose to be use).
Is that really worth it? If it is try at a small aperture, as I said.
But you'll lose any connection with the camera as well, and that means stop down metering...a real hassle...
12-21-2010, 04:33 PM   #11
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QuoteOriginally posted by Huck Finn Quote
Is that really worth it? If it is try at a small aperture, as I said.
But you'll lose any connection with the camera as well, and that means stop down metering...a real hassle...
correct me if i'm wrong (and I may well be).

manual lens has no connection to begin with, how would it lose connection with the camera?

Stop down metering is full manual right? you let the camera know the lens focal length (in this case it's a little off since the flanged distance is 1mm off), but I've seen people putting in the middle distance of zoom lens, so it shouldn't matter much right?

the reason why I'm doing this is because
1) the lens are really cheap (50mm f/1.4 is like 30-40 bucks).
2) it's probably worth the money for just portrait and macro
3) I'm really trying to juice it for my money haha.
12-21-2010, 04:53 PM   #12
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SR will be OK. You can use the lens in Av mode if you want, setting the aperture directly on the lens with its aperture ring. You'll need to focus first before setting aperture, because as you stop down, the viewfinder gets darker and DOF increases.
12-22-2010, 01:31 AM   #13
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QuoteOriginally posted by clockwork247 Quote
correct me if i'm wrong (and I may well be).

manual lens has no connection to begin with, how would it lose connection with the camera?

Stop down metering is full manual right? ...
No, not exactly. Or at least it depends on what you refer to the word "manual".
A manual lens such as a Pentax KA mount is manual focus, but all of the rest (exposure modes, metering modes, diaphragm operation) is fully automated.

A PK lens such as an M-series lens or a K-series lacks with modern digital Pentaxes also metering modes and program modes, you can only use them in manual mode and by manually operating the aperture ring.

A non Pentax lens or a screw mount lens (not always) or a T2 monut lens will also lack autimatic aperture operation. It means you'll have to actually stop down the diaphragm of your lens BEFORE you take the picture in order to meter. That will make your viewfinder really dim, and framing and focusing will become really hard.

You can still use the lens, but taking a shot will not be fast and easy, by any means.

All said you could make your life much easier by spending a few more buck and getting at least an M or K lens.
12-22-2010, 01:44 AM   #14
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Can you tell us what mount the lens uses? Your "1mm off" distance sounds like an Exakta mount. In the LENSES section I've documented a very simple way to adapt Exakta to PK, by grinding away a bit of an M42-PK adapter ring. If the lens is a Nikon mount (not AF) then the lens base is easily adapted, as are Olympus OM and Yashica C/Y mounts. And for 30-40 bucks for a 50/1.4, you may be overpaying. I recently got a C/Y Yashica ML 50/1.4 for ten bucks, and an M42 Sears-Tomioka 55/1.4 for two bucks. But I get lucky. OTOH if those are Topcon lenses (same geometry as Exakta) then 30-40 bucks is a real steal and I want your source!

Anyway, tell us about the lens, and we can suggest ways to use it.

As for the initial question: Loss of infinity focus manifests differently at various focal lengths. I sometimes mount M42 lenses using a safe cheap flanged no-infinity-focus M42-PK adapter, which add 1mm to the mount. On a 200mm lens, far-focus drops to ~80m; close-focus drops from 2.5m to 1.5m. On a 50mm lens, far-focus drops to ~4m. With that 50mm lens at f/22, hyperfocus at that far-focus point *should* extend DOF to ~infinity. Or so the voices in my head tell me. (I always trust my voices.) And on a 28mm lens, far-focus drops to just over 1m, which some portraitists will tell you is too close. Not me. I like close.
12-22-2010, 11:54 PM   #15
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QuoteOriginally posted by RioRico Quote
Can you tell us what mount the lens uses? Your "1mm off" distance sounds like an Exakta mount. In the LENSES section I've documented a very simple way to adapt Exakta to PK, by grinding away a bit of an M42-PK adapter ring. If the lens is a Nikon mount (not AF) then the lens base is easily adapted, as are Olympus OM and Yashica C/Y mounts. And for 30-40 bucks for a 50/1.4, you may be overpaying. I recently got a C/Y Yashica ML 50/1.4 for ten bucks, and an M42 Sears-Tomioka 55/1.4 for two bucks. But I get lucky. OTOH if those are Topcon lenses (same geometry as Exakta) then 30-40 bucks is a real steal and I want your source!

Anyway, tell us about the lens, and we can suggest ways to use it.

As for the initial question: Loss of infinity focus manifests differently at various focal lengths. I sometimes mount M42 lenses using a safe cheap flanged no-infinity-focus M42-PK adapter, which add 1mm to the mount. On a 200mm lens, far-focus drops to ~80m; close-focus drops from 2.5m to 1.5m. On a 50mm lens, far-focus drops to ~4m. With that 50mm lens at f/22, hyperfocus at that far-focus point *should* extend DOF to ~infinity. Or so the voices in my head tell me. (I always trust my voices.) And on a 28mm lens, far-focus drops to just over 1m, which some portraitists will tell you is too close. Not me. I like close.
where you get these for so cheap? let me get in on it lol.

Trying to find some M42 fast lens for cheap but I think it's nearly impossible these days.
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