Why do older camera lenses have faster F-stops?

Started Apr 14, 2013 | Discussions
EinsteinsGhost
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Re: f1.8 equivalents...
In reply to Joseph S Wisniewski, Apr 15, 2013

Joseph S Wisniewski wrote:

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

Yes, because it's micro four thirds, and the DOF and you need f0.9 to have the light gathering and DOF equivalent of the "plastic fantastic" $100 f1.8 lenses on FF. So, some old "cine" lenses get reincarnated.

DOF yes (at same FOV), exposure no.

Exposure yes.

Cut the sensor area into a quarter of what it was, and you have 1/4 of the photons in the picture, so you need to throw 4x the light at it to get the same results. Just like in the film days, when tri-x was probably my most shot film on the 4x5, while tech pan was one of my favorites on 35mm.

Physics is a bear.

Why would you need to throw 4x the number of photons in an area 1/4 the size for the same exposure?

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Joseph S Wisniewski
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Wimp!
In reply to Barrie Davis, Apr 15, 2013

Barrie Davis wrote:

vjk2 wrote:

I've gotten into vintage lenses lately, and it seems like with these older lenses, they're often much faster than the lenses I've gotten used to in the modern era.

I use Olympus and while I know that there is a 50mm f2.0 prime lens that costs $400, there are a number of less expensive vintage manual lenses I know of which will range from $50 for a f2 50mm to at most something like $150 for a f1.4

Could it be...what, autofocus, maybe the zoom design that makes modern lenses so dim?

It IS because the older lenses were of fixed focal length, not zooms, that the manufactures had more freedom to produce wide aperture designs.

Wide apertures were more necessary, too.

Like that Zeiss 50mm f0.7 that Kubrick snagged from NASA.

For a long time the fastest available colour film was 400 ASA (ISO)... the quality of which was so grainy (noisy) that people used it with reluctance, often choosing to stick with 100 ASA (ISO) stocks instead.... Slide films were even slower: The best Kodachrome was 25 ASA (ISO).

You youngsters, spoiled rotten by that fast Kodachrome 25. Everyone knows that the best stuff was the Kodachrome 8.

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Joseph S Wisniewski
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Re: f1.8 equivalents...
In reply to EinsteinsGhost, Apr 15, 2013

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

Yes, because it's micro four thirds, and the DOF and you need f0.9 to have the light gathering and DOF equivalent of the "plastic fantastic" $100 f1.8 lenses on FF. So, some old "cine" lenses get reincarnated.

DOF yes (at same FOV), exposure no.

Exposure yes.

Cut the sensor area into a quarter of what it was, and you have 1/4 of the photons in the picture, so you need to throw 4x the light at it to get the same results. Just like in the film days, when tri-x was probably my most shot film on the 4x5, while tech pan was one of my favorites on 35mm.

Physics is a bear.

Why would you need to throw 4x the number of photons in an area 1/4 the size for the same exposure?

Because, if you don't, you get very different pictures. A micro four thirds sensor at ISO 800 looks nothing like a FF sensor at that ISO, more like the FF sensor at ISO 3200. Same number of photons makes for the same image.

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EinsteinsGhost
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Re: f1.8 equivalents...
In reply to Joseph S Wisniewski, Apr 15, 2013

Joseph S Wisniewski wrote:

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

Yes, because it's micro four thirds, and the DOF and you need f0.9 to have the light gathering and DOF equivalent of the "plastic fantastic" $100 f1.8 lenses on FF. So, some old "cine" lenses get reincarnated.

DOF yes (at same FOV), exposure no.

Exposure yes.

Cut the sensor area into a quarter of what it was, and you have 1/4 of the photons in the picture, so you need to throw 4x the light at it to get the same results. Just like in the film days, when tri-x was probably my most shot film on the 4x5, while tech pan was one of my favorites on 35mm.

Physics is a bear.

Why would you need to throw 4x the number of photons in an area 1/4 the size for the same exposure?

Because, if you don't, you get very different pictures. A micro four thirds sensor at ISO 800 looks nothing like a FF sensor at that ISO, more like the FF sensor at ISO 3200. Same number of photons makes for the same image.

"Very different picture" will be in terms of DOF and FOV. A 50mm f/1.4 on MFT will produce the same FOV as 100mm f/2.8 lens on FF.

As a matter of fact, smaller sensor is simply throwing away the light that falls outside of it (which a larger sensor uses for additional FOV).

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BertIverson
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Joseph --- I remember ASA 10 Kodachrome ...
In reply to Joseph S Wisniewski, Apr 15, 2013

Joseph S Wisniewski wrote:

You youngsters, spoiled rotten by that fast Kodachrome 25. Everyone knows that the best stuff was the Kodachrome 8.

I remember Kodachrome 10 but too young to remember 8
Was there really an ASA 8 ?
Bert

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Barrie Davis
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Re: Wimp!
In reply to Joseph S Wisniewski, Apr 15, 2013

Joseph S Wisniewski wrote:

Barrie Davis wrote:

vjk2 wrote:

I've gotten into vintage lenses lately, and it seems like with these older lenses, they're often much faster than the lenses I've gotten used to in the modern era.

I use Olympus and while I know that there is a 50mm f2.0 prime lens that costs $400, there are a number of less expensive vintage manual lenses I know of which will range from $50 for a f2 50mm to at most something like $150 for a f1.4

Could it be...what, autofocus, maybe the zoom design that makes modern lenses so dim?

It IS because the older lenses were of fixed focal length, not zooms, that the manufactures had more freedom to produce wide aperture designs.

Wide apertures were more necessary, too.

Like that Zeiss 50mm f0.7 that Kubrick snagged from NASA.

For a long time the fastest available colour film was 400 ASA (ISO)... the quality of which was so grainy (noisy) that people used it with reluctance, often choosing to stick with 100 ASA (ISO) stocks instead.... Slide films were even slower: The best Kodachrome was 25 ASA (ISO).

You youngsters, spoiled rotten by that fast Kodachrome 25. Everyone knows that the best stuff was the Kodachrome 8.

I don't remember K8, but my Daddy used K10, or was it K12? Hmm...

Which came first of KII and K25.... ?
Was it KII?
If so, it was my fave.. the later film was just a bit too soft.

By the K64 era I was a pro, and mail order shooting on E2/E3 most of the time. I remember we had to keep seperate processing lines for rollfilm E2, and sheets E3. 
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Joseph S Wisniewski
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Weston 8, GE 12, ASA 10...
In reply to Barrie Davis, Apr 15, 2013

Barrie Davis wrote:

Joseph S Wisniewski wrote:

Barrie Davis wrote:

vjk2 wrote:

I've gotten into vintage lenses lately, and it seems like with these older lenses, they're often much faster than the lenses I've gotten used to in the modern era.

I use Olympus and while I know that there is a 50mm f2.0 prime lens that costs $400, there are a number of less expensive vintage manual lenses I know of which will range from $50 for a f2 50mm to at most something like $150 for a f1.4

Could it be...what, autofocus, maybe the zoom design that makes modern lenses so dim?

It IS because the older lenses were of fixed focal length, not zooms, that the manufactures had more freedom to produce wide aperture designs.

Wide apertures were more necessary, too.

Like that Zeiss 50mm f0.7 that Kubrick snagged from NASA.

For a long time the fastest available colour film was 400 ASA (ISO)... the quality of which was so grainy (noisy) that people used it with reluctance, often choosing to stick with 100 ASA (ISO) stocks instead.... Slide films were even slower: The best Kodachrome was 25 ASA (ISO).

You youngsters, spoiled rotten by that fast Kodachrome 25. Everyone knows that the best stuff was the Kodachrome 8.

I don't remember K8, but my Daddy used K10, or was it K12? Hmm...

Both.

Kodachrom predates ASA film speeds. There were a bunch of systems in use at the time, and Kodak rated their 1936 Kodachrome at Weston 8 or GE 12, based on how those two electronics companies decided to calibrate their meters.

ASA is basically an "average" of the common film speed systems, so the first Kodachrome to have an ASA rating in 1945 ended up ASA 10.

There was supposedly an ASA 6 Kodachrome sheet film. That must have been something.

Which came first of KII and K25.... ?
Was it KII?

1955 for the K II line. They were probably up to ASA 25 by then.

If so, it was my fave.. the later film was just a bit too soft.

By the K64 era I was a pro, and mail order shooting on E2/E3 most of the time. I remember we had to keep seperate processing lines for rollfilm E2, and sheets E3.

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MisterBG
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Re: Why do older camera lenses have faster F-stops?
In reply to EinsteinsGhost, Apr 15, 2013

SergioNevermind touched on the reasons for faster F-stops in his post.

On manual focus SLR's you relied on a "split image" or later a "microprism" focussing aid in the viewfinder. These needed plenty of light to function. I recall manufacturer warnings that smaller aperture telephoto lenses (F4 or less) would tend to cause half of the split image focussing screen to black out. This was especially true when using a teleconvertor with a longer focus lens, when split image viewfinders became useless.
The secondary reason was because film speeds were much lower in those days, which meant larger apertures were needed. Average speeds were ASA (ISO) 100 or lower, and 400 ASA was about as fast as you could get with easily available films. With pushed processing you could uprate Black and White 400 to 800 ASA or a little more, but at the expense of an increase in contrast.

Modern autofocus does not rely on having a bright image, so manufacturers can make lenses with a smaller maximum aperture, which are consequently cheaper to produce.

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SergioNevermind
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Re: Why do older camera lenses have faster F-stops?
In reply to Barrie Davis, Apr 15, 2013

Barrie Davis wrote:

SergioNevermind wrote:

Older film lenses, specially in the manual focus era (pre 90's) had to deal not only with limited ISO film but also with the ability to allow you to focus manually using in the best case a split image viewfinder. A brighter lens wide open may not be sharp, but it will help you focus, and then stop down and then click.

So autofocus, plus digital sensors capable of getting higher ISO than film with decent results, gave designers the chance to make MUCH MORE CHEAPER lenses, just as APSC kit zooms, e.g. 18-55 f 3,5-5,6. Won't get any DOF at any focal length out of that.

Huh?!

Errr... do you mean, "won't get any SHALLOW DoF out of that...??"
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Thank you for your correction.

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MiLei
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Re: Why do older camera lenses have faster F-stops?
In reply to vjk2, Apr 15, 2013

What I remember of really old film times is that you wanted a fast lens. A good reason for those was the limited sortiment of films like others have said. But people also talked about lens speeds like we today talk about megapixels. If you were a serious? photographer you used fast lenses. And of course Canon and Nikon were happy to sell those. Like some big white tubes of today.

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The Davinator
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Re: f1.8 equivalents...
In reply to Joseph S Wisniewski, Apr 16, 2013

Joseph S Wisniewski wrote:

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

Yes, because it's micro four thirds, and the DOF and you need f0.9 to have the light gathering and DOF equivalent of the "plastic fantastic" $100 f1.8 lenses on FF. So, some old "cine" lenses get reincarnated.

DOF yes (at same FOV), exposure no.

Exposure yes.

Cut the sensor area into a quarter of what it was, and you have 1/4 of the photons in the picture, so you need to throw 4x the light at it to get the same results. Just like in the film days, when tri-x was probably my most shot film on the 4x5, while tech pan was one of my favorites on 35mm.

Physics is a bear.

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Exposure...no.  I get the same shutter and aperture rating using a FF camera at iso 100 and f8 as I do on an m43 body.

exposure...no.

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The Davinator
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Re: Why do older camera lenses have faster F-stops?
In reply to JulesJ, Apr 16, 2013

JulesJ wrote:

edispics wrote:

Faster lenses were more important back "then" because it was exceedingly difficult to take high ISO, low noise photos, so those additional F stops really made a difference.

This sort of answers it.

Could also amount to a brighter image in the viewfinder in order to focus

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Re: Why do older camera lenses have faster F-stops?
In reply to EinsteinsGhost, Apr 16, 2013

In this case, you are likely comparing price of a new lens to some very much used lenses. For example, I bought a Vivitar Series I 70-210mm f/2.8-4 (Konica AR-mount) for my Sony NEX and paid only $50 for it. That included shipping. This wasn’t a cheap lens in its day, in fact it was premium priced.  When we also account for inflation adjustment, it is likely we may actually be paying less today for many lenses and a part of it has to do with using cheaper markets for building them.

A Popular Photography May 1975 magazine ad shows $295 for the Vivitar 70-210mm F3.5 lens. Cameras which came with a 50mm f1.8 could get an F1.4 for $30 more.

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EinsteinsGhost
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Re: Why do older camera lenses have faster F-stops?
In reply to SonyForNow, Apr 16, 2013

SonyForNow wrote:

In this case, you are likely comparing price of a new lens to some very much used lenses. For example, I bought a Vivitar Series I 70-210mm f/2.8-4 (Konica AR-mount) for my Sony NEX and paid only $50 for it. That included shipping. This wasn’t a cheap lens in its day, in fact it was premium priced.  When we also account for inflation adjustment, it is likely we may actually be paying less today for many lenses and a part of it has to do with using cheaper markets for building them.

A Popular Photography May 1975 magazine ad shows $295 for the Vivitar 70-210mm F3.5 lens. Cameras which came with a 50mm f1.8 could get an F1.4 for $30 more.

Adjusted for inflation, that will be a $130 premium over 1.8, and Vivitar 70-210 f/3.5 would be $1300 in today's money.

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Barrie Davis
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Good Depth of Field
In reply to SergioNevermind, Apr 16, 2013

SergioNevermind wrote:

Barrie Davis wrote:

SergioNevermind wrote:

Older film lenses, specially in the manual focus era (pre 90's) had to deal not only with limited ISO film but also with the ability to allow you to focus manually using in the best case a split image viewfinder. A brighter lens wide open may not be sharp, but it will help you focus, and then stop down and then click.

So autofocus, plus digital sensors capable of getting higher ISO than film with decent results, gave designers the chance to make MUCH MORE CHEAPER lenses, just as APSC kit zooms, e.g. 18-55 f 3,5-5,6. Won't get any DOF at any focal length out of that.

Huh?!

Errr... do you mean, "won't get any SHALLOW DoF out of that...??"

Thank you for your correction.

My question was prompted by the new tendency to use the term "Depth of Field" as if it automatically meant SHALLOW Depth of Field.

For instance, we see "good DoF" as if it refers to the background blur that is, by definition, quite OUTSIDE of depth of field.

This use of terms is confusing.

Historically, "good DoF" has always meant plenty of depth to the DoF referred to...

.... and NOT the opposite (shallowness).

It is my opinion it would be nice if we could keep it that way, for the sake of continuity, and of clarity.

Thanks.

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EinsteinsGhost
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Re: Good Depth of Field
In reply to Barrie Davis, Apr 16, 2013

Barrie Davis wrote:

Historically, "good DoF" has always meant plenty of depthto the DoF referred to...

.... and NOT the opposite (shallowness).

It is my opinion it would be nice if we could keep it that way, for the sake of continuity, and of clarity.

I couldn’t care less about whether a historical perspective entailed either a deep or a shallow DOF for good DOF, personally to me, a good DOF isn’t defined on such “fixed” terms, rather, how it renders for a situation. It could be shallow, it could be deep, or somewhere in between.

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Joseph S Wisniewski
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Re: f1.8 equivalents...
In reply to The Davinator, Apr 16, 2013

Dave Luttmann wrote:

Joseph S Wisniewski wrote:

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

Yes, because it's micro four thirds, and the DOF and you need f0.9 to have the light gathering and DOF equivalent of the "plastic fantastic" $100 f1.8 lenses on FF. So, some old "cine" lenses get reincarnated.

DOF yes (at same FOV), exposure no.

Exposure yes.

Cut the sensor area into a quarter of what it was, and you have 1/4 of the photons in the picture, so you need to throw 4x the light at it to get the same results. Just like in the film days, when tri-x was probably my most shot film on the 4x5, while tech pan was one of my favorites on 35mm.

Physics is a bear.

Exposure...no.  I get the same shutter and aperture rating using a FF camera at iso 100 and f8 as I do on an m43 body.

exposure...no.

Exposure... yes.

Come on Dave, you've shot many different film formats and different digital formats. Do you shoot the same ISO in all formats?

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EinsteinsGhost
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Re: f1.8 equivalents...
In reply to Joseph S Wisniewski, Apr 16, 2013

Joseph S Wisniewski wrote:

Dave Luttmann wrote:

Joseph S Wisniewski wrote:

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

Yes, because it's micro four thirds, and the DOF and you need f0.9 to have the light gathering and DOF equivalent of the "plastic fantastic" $100 f1.8 lenses on FF. So, some old "cine" lenses get reincarnated.

DOF yes (at same FOV), exposure no.

Exposure yes.

Cut the sensor area into a quarter of what it was, and you have 1/4 of the photons in the picture, so you need to throw 4x the light at it to get the same results. Just like in the film days, when tri-x was probably my most shot film on the 4x5, while tech pan was one of my favorites on 35mm.

Physics is a bear.

Exposure...no.  I get the same shutter and aperture rating using a FF camera at iso 100 and f8 as I do on an m43 body.

exposure...no.

Exposure... yes.

Come on Dave, you've shot many different film formats and different digital formats. Do you shoot the same ISO in all formats?

No, it doesn't. The f-stop equivalence applies to DOF, not to exposure.

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Barrie Davis
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Re: Good Depth of Field
In reply to EinsteinsGhost, Apr 17, 2013

EinsteinsGhost wrote:

Barrie Davis wrote:

Historically, "good DoF" has always meant plenty of depthto the DoF referred to...

.... and NOT the opposite (shallowness).

It is my opinion it would be nice if we could keep it that way, for the sake of continuity, and of clarity.

I couldn’t care less about whether a historical perspective entailed either a deep or a shallow DOF for good DOF, personally to me, a good DOF isn’t defined on such “fixed” terms, rather, how it renders for a situation. It could be shallow, it could be deep, or somewhere in between.

Which doesn't clarify a darn, thing does it? Useless.

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Re: f1.8 equivalents...
In reply to EinsteinsGhost, Apr 17, 2013

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

Dave Luttmann wrote:

Joseph S Wisniewski wrote:

EinsteinsGhost wrote:

Joseph S Wisniewski wrote:

Yes, because it's micro four thirds, and the DOF and you need f0.9 to have the light gathering and DOF equivalent of the "plastic fantastic" $100 f1.8 lenses on FF. So, some old "cine" lenses get reincarnated.

DOF yes (at same FOV), exposure no.

Exposure yes.

Cut the sensor area into a quarter of what it was, and you have 1/4 of the photons in the picture, so you need to throw 4x the light at it to get the same results. Just like in the film days, when tri-x was probably my most shot film on the 4x5, while tech pan was one of my favorites on 35mm.

Physics is a bear.

Exposure...no.  I get the same shutter and aperture rating using a FF camera at iso 100 and f8 as I do on an m43 body.

exposure...no.

Exposure... yes.

Come on Dave, you've shot many different film formats and different digital formats. Do you shoot the same ISO in all formats?

No, it doesn't. The f-stop equivalence applies to DOF, not to exposure.

Ahh... That is what you think, is it?  I'll bear your opinion in mind for the future.

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