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12-16-2013, 09:29 AM   #76
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QuoteOriginally posted by phreon Quote
Probably similar to the reaction a C330F with waist level viewfinder, grip/flash bracket, flash, bounce hood and cabling to make it work gets. "What is THAT?!?!", "Why does it have two lenses?!?"

Do people scream and run in horror as their ears bleed and buildings crumble after you hit the shutter release on that P67?
People just stare and the odd one will ask what type of camera it is. Fellow Pentax users will sometimes stop and talk, which is always nice. I also get film shooters of other brands interested in these old Pentax cameras. (I also shoot 35mm film)

However I’ve never had anyone with a Nikon/Cannon DSLR ever talk to me or even make eye contact. Strange bunch they are!

I did have a horse bolt once when I was using my Pentax film K2, it also has a rather loud shutter.

Phil.

12-16-2013, 10:47 AM   #77
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QuoteOriginally posted by gofour3 Quote
People just stare and the odd one will ask what type of camera it is. Fellow Pentax users will sometimes stop and talk, which is always nice. I also get film shooters of other brands interested in these old Pentax cameras. (I also shoot 35mm film)

However I’ve never had anyone with a Nikon/Cannon DSLR ever talk to me or even make eye contact. Strange bunch they are!

I did have a horse bolt once when I was using my Pentax film K2, it also has a rather loud shutter.

Phil.
Louder than the P67? Maybe a bit of hyperbole, but I'd swear the shutter release activates explosive bolts.
12-16-2013, 11:13 AM   #78
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QuoteOriginally posted by phreon Quote
Louder than the P67? Maybe a bit of hyperbole, but I'd swear the shutter release activates explosive bolts.
No the 6x7s have louder shutters, but no one (human or animal) have reacted to it yet.

Phil.
12-18-2013, 10:25 AM   #79
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QuoteOriginally posted by davids8560 Quote
Hi! So, like, I am kind of new, and I want to get this joke. What's it refer to? Sorry but I'm really honestly serious, if you could explain it!
I bought a Pentax Fa 50mm f/1.4 which auto focuses just fine at f/1.4 because the depth of field isn't really that narrow. It depends on the lens, understand its nuances and you'll get the hang of it. Typically lens reviewers complain about this because they are of the Canikon school of photography, which is a photojournalism style with f/2.8 zooms. They find themselves out of their depth because they don't know what to do with a f/1.4 lens.

QuoteOriginally posted by davids8560 Quote
So if eventually I get a fast prime I should expect to have to manually focus when shooting very wide?
No ! You'll be fine on a modern AF f/1.4 you just have to practice how to use narrow depth of field photography. I bought an old fully manual Pentax M 50mm f/1.7 which has a ridiculous narrow depth of field making it near impossible to use on close ups - but with practice and patients I'll get it. Much old lenses can have a ridiculously narrow depth of field which makes them interesting, but you'll be fine on a modern model (1990's and older).

QuoteOriginally posted by davids8560 Quote
Do you think it's possible to learn photography just by shooting a lot and trying different settings? Because to be frank I am not so big on lots of reading and book study, and it seems like my photography study and reading list is growing longer and longer and piling up big time! LOL
When you are new, you need to keep it simple and don't over think it:
* Put the camera on Aperture priority and experiment with depth of field.
* Watch your white balance. Put it on auto or change it to experiment ("shade for shooting" in the shade etc.)
* Watch your ISO setting. Put it on auto or increase the ISO when you want a faster shutter for capturing fountains or fast action.
* and hold the camera steady.

12-18-2013, 10:49 AM   #80
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Err... A 50mm 1.4 lens has less DOF than a 50mm 1.7 lens. It doesn't matter if a lens was made 4 or 40 years ago.
12-18-2013, 11:05 AM   #81
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QuoteOriginally posted by Giklab Quote
Err... A 50mm 1.4 lens has less DOF than a 50mm 1.7 lens. It doesn't matter if a lens was made 4 or 40 years ago.
No I'm not kidding you my M 50mm f/1.7 is less then the 50 f/1.4. Take a look at the Pentax forums lens reviews and some people talk about the "razor thin" depth of field on the 50mm 1.7.
12-18-2013, 11:23 AM   #82
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QuoteOriginally posted by zoolander Quote
No I'm not kidding you my M 50mm f/1.7 is less then the 50 f/1.4. Take a look at the Pentax forums lens reviews and some people talk about the "razor thin" depth of field on the 50mm 1.7.
Depth of field is purely a function of focal length, f-stop and distance to subject, nothing else. Every 50mm lens ever made set at f2.0 for example will have the exact same depth of field. All things being equal, the only reason one 50mm would be harder to focus than another 50mm is that the mechanism is course and therefore harder to "micro-adjust". Well and that an f1.7 lens gathers less light wide open than a 1.4 and could be a bit harder to see in low light conditions.

Any lens capable of f1.4 will *always* have a shallower DoF wide open than a (same focal length) 1.7, 1.8, 2.0, etc. It's "Photography 101".

Last edited by phreon; 12-18-2013 at 11:47 AM.
12-18-2013, 11:54 AM   #83
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QuoteOriginally posted by zoolander Quote
No I'm not kidding you my M 50mm f/1.7 is less then the 50 f/1.4. Take a look at the Pentax forums lens reviews and some people talk about the "razor thin" depth of field on the 50mm 1.7.
I can only think of one scenario when this would be even remotely possible (and half a dozen reasons why it may seem this way).

Put the camera on a spot, take a shot with both lenses without moving the camera (focus manually on the same spot). Then see if one lens has a shorter focal length than the other (if it has a wider FOV).

12-18-2013, 12:15 PM   #84
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QuoteOriginally posted by phreon Quote
Depth of field is purely a function of focal length, f-stop and distance to subject, nothing else. Every 50mm lens ever made set at f2.0 for example will have the exact same depth of field. All things being equal, the only reason one 50mm would be harder to focus than another 50mm is that the mechanism is course and therefore harder to "micro-adjust". Well and that an f1.7 lens gathers less light wide open than a 1.4 and could be a bit harder to see in low light conditions.

Any lens capable of f1.4 will *always* have a shallower DoF wide open than a 1.7, 1.8, 2.0, etc. It's "Photography 101".
Do you own the Pentax FA 50mm f/1.4 and the Pentax M f/1.7 ? Okay, I own them both, and the M f1.7 has a narrower depth of field. If this was the other way around (me being in your shoes), I wouldn't believe me either. When I bought the M f/1.7 I thought something was drastically wrong with it, but I checked what the reviewers say and people describe it as having a razor thin depth of field. You don't believe it - then don't believe it. Its a very difficult lens to use. Hey, maybe somethings wrong with it, but the reviewers on Pentax forums concur the razor thin depth of field.
12-18-2013, 02:16 PM   #85
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QuoteOriginally posted by zoolander Quote
Do you own the Pentax FA 50mm f/1.4 and the Pentax M f/1.7 ? Okay, I own them both, and the M f1.7 has a narrower depth of field. If this was the other way around (me being in your shoes), I wouldn't believe me either. When I bought the M f/1.7 I thought something was drastically wrong with it, but I checked what the reviewers say and people describe it as having a razor thin depth of field. You don't believe it - then don't believe it. Its a very difficult lens to use. Hey, maybe somethings wrong with it, but the reviewers on Pentax forums concur the razor thin depth of field.

As Giklab alluded, what you're describing is only possible if the 50mm f1.7 isn't exactly 50mm. Or it's actually faster than f1.4. I don't need to own both lenses because what you're describing flies in the face of basic optics. Maybe the f1.7's mechanism is touchy and harder to focus, but if it's a true 50mm (same magnification) as the f1.4 and the subject is the same distance from the lens's nodal point, both *must* have the same DoF at same apertures, with the f1.4 capable of shorter DoF wide open.

Depth of field
12-21-2013, 07:01 AM   #86
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QuoteOriginally posted by phreon Quote
As Giklab alluded, what you're describing is only possible if the 50mm f1.7 isn't exactly 50mm. Or it's actually faster than f1.4. I don't need to own both lenses because what you're describing flies in the face of basic optics. Maybe the f1.7's mechanism is touchy and harder to focus, but if it's a true 50mm (same magnification) as the f1.4 and the subject is the same distance from the lens's nodal point, both *must* have the same DoF at same apertures, with the f1.4 capable of shorter DoF wide open.

Depth of field
Here's a link to a picture from the Flickr Pentax M 1.7 group with an example of how narrow the depth of field is (there's a second similar image click on the arrow left):

It's The Modern World | Flickr - Photo Sharing!

Here's a link to a picture from the SMC FA 50mm f/1.4 group on flickr, showing an example of the depth of field (pay attention to the top of the camera in the image for DOF):

Warilla Bowling Club FlickrMeet - Harry tests the Pentax K10D | Flickr - Photo Sharing!

Those are not my own pictures, the image from the 1.4 is at a lower angle to the 1.7, but depth of field is more than obvious, and the 1.7 is narrower wide open - just like I said, and I've shown it with contemporary evidence.
12-21-2013, 08:09 AM   #87
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First, what you are describing is highly subjective. The scenes are different, the angle is different and most importantly we don't know the distance to subject.They look perhaps similar, but at these distances, small changes have a large effect. A real test would be to have the camera on a tripod pointed at a given subject and then change lenses w/o moving anything.

Besides, if you look at the EXIF data for the picture ostensibly taken with the FA f1.4, you'll see that the aperture was set at 2.0. At the same subject to lens distance, the f1.4 *wide open* will have a shallower DoF than the f1.7 *wide open*. You are arguing fundamentals of optics and photography that were settled long before any of us were born.

Last edited by phreon; 12-21-2013 at 09:23 AM.
12-21-2013, 10:19 AM   #88
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Think of it this way, Zoolander.

A camera lens bends light towards the film or image sensor as a cone. Think of an ice cream cone made of light. Only if the extreme point of the cone exactly touches the film or sensor will the image be in perfect focus.

With a wide aperture the cone of light widens very quickly, so that it quickly becomes obvious that the image is out of focus. For present purposes we’ll call this effect “shallow depth of field.”

With a narrow aperture the cone of light widens a lot more slowly, so that parts of the image can still be acceptably sharp even if they aren’t in perfect focus at the exact point of the cone. For now we’ll call this “deep depth of field.”

Used wide open, a 50mm f/1.4 lens has a physically larger aperture than a 50mm f/1.7 lens, which means that it projects a wider cone of light, which means that it has shallower depth of field. You can’t alter this fact any more than you can switch off the force of gravity.

Since somebody is bound to raise the issue:

Depth of FIELD is the zone IN FRONT OF THE LENS within which objects in the real world appear acceptably sharp.

Depth of FOCUS is the zone near the point of the cone of light PROJECTED BY THE LENS within which the image formed on the film or sensor appears acceptably sharp.

I’ve used the term “depth of field” above to try to keep things simple. Anyone attempting to introduce the term “circle of confusion” into the discussion will be shot with a blunt bullet.
12-21-2013, 01:08 PM   #89
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QuoteOriginally posted by Dartmoor Dave Quote
Think of it this way, Zoolander.

A camera lens bends light towards the film or image sensor as a cone. Think of an ice cream cone made of light. Only if the extreme point of the cone exactly touches the film or sensor will the image be in perfect focus.

With a wide aperture the cone of light widens very quickly, so that it quickly becomes obvious that the image is out of focus. For present purposes we’ll call this effect “shallow depth of field.”

With a narrow aperture the cone of light widens a lot more slowly, so that parts of the image can still be acceptably sharp even if they aren’t in perfect focus at the exact point of the cone. For now we’ll call this “deep depth of field.”

Used wide open, a 50mm f/1.4 lens has a physically larger aperture than a 50mm f/1.7 lens, which means that it projects a wider cone of light, which means that it has shallower depth of field. You can’t alter this fact any more than you can switch off the force of gravity.

Since somebody is bound to raise the issue:

Depth of FIELD is the zone IN FRONT OF THE LENS within which objects in the real world appear acceptably sharp.

Depth of FOCUS is the zone near the point of the cone of light PROJECTED BY THE LENS within which the image formed on the film or sensor appears acceptably sharp.

I’ve used the term “depth of field” above to try to keep things simple. Anyone attempting to introduce the term “circle of confusion” into the discussion will be shot with a blunt bullet.
Dartmoor Dave, the only possible explanation would require bringing up the "circle of confusion". It's just possible that the f1.4 is softer than the 1.7 wide open. Therefore, the apparent DoF might seem crisper or more defined with the f1.7 than the f1.4 wide open, but in relative terms, the f1.4 will still have a smaller DoF. This would seem more likely with my old SMC M f1.4 than a newer FA, since there newer ones are considered sharper than the older ones (if one believes the Internet).
12-21-2013, 01:17 PM   #90
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This is a thread about "Are we old school?"
No it is about lenses.
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