Tell us WHY you shoot adapted!

Started 3 months ago | Discussions
ProfHankD
ProfHankD Veteran Member • Posts: 8,060
OOF PSF

Alan WF wrote:

That's really great, but if you look closely, where it's wrong, it's often VERY wrong. For example, see the red spots in the lower left corner. Why?

Cool! I’ve often wondered why you got into OOF PSFs, and now I know.

I'm not going to go through all of this here -- take a look at my Poorly Focused Talk for the full details and explanation -- but there's tons of information you can get about the scene and the lens by studying the details within the OOF image of a point of light. Oddly enough, there wasn't even a name for such a thing, but the in-focus image of a point of light was known as the PSF (point spread function), so I called this the OOF PSF

In my neck of the physical sciences we’ve been calling these “intrafocal images” and “extrafocal images” since Johannes Hartmann was knee-high to a grasshopper and surely before that.

Interesting how things can be common in one niche and completely missing in other, logically closely related, ones.

Certainly, optical designers and photographers have often paid some attention to the OOF properties of lenses from as soon as lenses had apertures bigger than pinholes. However, in conventional photography, I'm only aware of people regularly measuring very slightly OOF PSFs -- in a range where diffraction effects and differences in focus plane for different wavelengths dominate the structure. That seems to dominate the telescope usage as well, where most still seem to be in the range of seeing Airy discs.

In the Electronic Imaging community, looking at PSFs that are significantly OOFwas treated as pretty radical -- including by my friends at Imatest -- when I started pushing it as a primary metric in 2014. My use of OOF PSF dates from 2009. To this day, the vast majority of image processing software still models defocus as a Gaussian blur. You'd think at least the folks doing "Coded Aperture" work, which relies on being significantly OOF, would get this right, and they sort-of do, but all their aperture masks consist of square-pixel patterns for which the corners of the squares (and at lesser defocus, the squares themselves) cause diffraction effects.

We use them to diagnose aberrations, not estimate depth, since our subjects are effectively at infinity

I use them not only to measure scene depth (and all the same tricks you can do with lightfield photography), but also to predict/create bokeh properties, forensically identify the type of lens or even specific copy of a lens used (e.g., by dust pattern), and to diagnose/measure a variety of larger-scale optical defects including decentering, separation, fungus, etc. There's a lot of information in a significantly OOF PSF that's very difficult to obtain from nearly in-focus images... and I'm still finding more -- just a couple of years ago, I realized OOF PSF images extracted from natural scenes can be used to estimate the aperture setting used by matching aperture blade shapes.

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ProfHankD
ProfHankD Veteran Member • Posts: 8,060
Cost vs. modern lenses
1

PhotosByHall wrote:

Finally it's no longer a cheap way to access great glass - every man and his dog is in on this now - some manual lenses cost more than their modern AF counterparts. If I am losing AF, I need to save $$$$.

Losing AF isn't something I generally view as a disadvantage if in trade I get smooth and precise manual focus... but I agree about cost for old vs. new lenses.

If the optical performance of an old lens and new one is similar, I expect to pay significantly less for the used lens... and perhaps even less if the used lens is pretty old. For example, I'll never understand why people spend more on a really poor quality old ultrawide than on a brand new lens that's optically much better.

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OP billorg Senior Member • Posts: 1,296
Re: Tell us WHY you shoot adapted!

RvL001 wrote:

Partially nostalgia. The Meyer-Optik Orestor 135mm f/2.8 is the lens that got me into photography in the first place, together with the Exakta Vx500 it was attached to. Both belonged to my dad, who unfortunately past away last January. So being able to use his gear again means a lot to mean.

I also have a Canon FDn 50mm f/1.4 which I use very regularly.

Using adapted and especially MF lenses also makes me take more time to take a picture. Way less 'spray & pray', more time for composition, focussing, determining aperture and shutter speed etc. And it's much more satisfactory to nail a photo having to work this way.

All in all I think I use my adapted lenses more often than my native EF-M 18-150mm.

I too like that shooting manual makes you think again and appreciate good results done the hard way.

Bill

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OP billorg Senior Member • Posts: 1,296
Re: Tell us WHY you shoot adapted!

..
This thread: http://www.fredmiranda.com/forum/topic/969329 convinced me to buy a NEX camera.
I was looking for a good deal on a 5N when Sony announced the NEX-7, it had a built in EVF which I really wanted, then Steve Huff released his review with the hot-air balloon shot, I was sold, the NEX-7 would be my next camera.
I ended up with a NEX-7 that spring, I still wanted a FF camera, but could easily look past that due to the quality I was getting from it.
I was astounded by how easy it was to nail focus, if I wanted to place the plane of focus at the tip of something, I could, the 7 easily become my most favourite camera ever, after setting it up it was so intuitive to use, it could get out of my way in such a way that I could get into a creative zone of thought I had never experienced before, the subject was the only thing that existed, in a word... Nirvana.
I was immediately and vocally calling for a FF NEX-7, it took a few years for the A7 & A7r to be announced and I jumped for joy(sort of, the form factor was not the same), ahhh, at last, a FF sensor that wasn't so expensive and finally my legacy lenses that I was loving so much were now back to their original FOV, a 28mm lens wide again, cue the celebrations!

Never has it been better to be a photographer.

so great!  I too love my NEX 5n, my thing is low noise at high iso, and only this one has held up over the years till Sony came out with the ff bodies.  I use mine with the Zeiss rangefinder lenses and can also use Maxxum lenses, but the point of the NEX and the ting rangefinder lenses is the super small and elegant package that you can take anywhere.  I have an 18 and 28mm so I can do great street scenes and landscapes without a worry about focus, since it’s pretty much infinity focus past a certain point.  I use the focus peaking in yellow just to confirm.  Tack sharp images! Bill

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OP billorg Senior Member • Posts: 1,296
Re: Tell us WHY you shoot adapted!
1

Erichimedes wrote:

Great question! Some interesting answers here.

I'm a fan of old, well made things. In my job, I do a lot of work on metalworking machines (mills, lathes, etc.) that are 30-40 years old. Buying the machines, fixing them up so they can do good work and using them to to do my work is something I really enjoy. I often pair the old machines with modern tooling, and it's cool to see the blend of old and new working together.

I saw an old lens adapted to a mirrorless camera not long after buying my Sony, and I thought, now THAT is something I want to try. I've always been a bit of a gear guy, and I really like trying out many different types of lenses just to see what they're like. Adapting lets me actually do that within my budget.

I actually really enjoy manually focusing in 90% of the shooting I do. And having such a wonderful, tactile control of the aperture that's directly connected to the iris is just amazing to me. Just holding old purely mechanical lenses makes me happy.

Nothing like the feeling of my heavy LITTLE Zeiss rangefinder lenses in my hand!

Bill

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Bob Janes
Bob Janes Veteran Member • Posts: 4,587
Re: Tell us WHY you shoot adapted!
2

billorg wrote:

Is it more because you like to "make do" with what you have, OR you like to buy less expensive lenses for cameras you already have OR do you buy expensive new cameras or lenses because you are searching for that holy grail combination of best lens coupled with the best sensor? Or maybe another reason?

I tend to be in the last category. I have NEW Zeiss rangefinder lenses that I use with a Sony mirrorless body because I have always loved Zeiss lenses since the Rolleiflex twin lens camera days. I also have vintage Minolta Maxxum lenses that I use on my Sony A99 because those lenses just have a special quality to them, almost 3D and wonderful color. Love to hear from all of you. Bill

Because there are some really interesting lenses out there.

I shoot full-frame purely to use old lenses. One of my favourite lenses is the Zenitar 16mm f/2.8 - works great on a DSLR and you don't miss autofocus at all with something that wide.

I have an extensive analogue camera collection and it is great to be able to use various Takumar, Rokkor, Hexanon and Zuiko lenses on a digital sensor.

With a full frame mirrorless camera the options on what can be adapted open up plus you get a bright viewfinder and focusing aids.

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JasonTheBirder
JasonTheBirder Senior Member • Posts: 2,088
Re: Tell us WHY you shoot adapted!

I have a Panasonic G9 for video and stills. One of the nicest cameras I ever used.

Anyway, I adapt manual lenses onto it for video since the focus rings of older manual lenses are very smooth and easier to do smooth focus pulls compared to some more modern lenses.

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FKS
FKS Veteran Member • Posts: 3,222
Re: Tell us WHY you shoot adapted!
1

Several reasons:

1. I have lenses from my film bodies of various mounts.
2. Old lenses are cheap-ish.
3. Old lenses have a different rendering that can be pleasing.
4. There's a visceral reward to focusing with a MF lens.

billorg wrote:

Is it more because you like to "make do" with what you have, OR you like to buy less expensive lenses for cameras you already have OR do you buy expensive new cameras or lenses because you are searching for that holy grail combination of best lens coupled with the best sensor? Or maybe another reason?

I tend to be in the last category. I have NEW Zeiss rangefinder lenses that I use with a Sony mirrorless body because I have always loved Zeiss lenses since the Rolleiflex twin lens camera days. I also have vintage Minolta Maxxum lenses that I use on my Sony A99 because those lenses just have a special quality to them, almost 3D and wonderful color. Love to hear from all of you. Bill

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Erichimedes Forum Member • Posts: 94
Re: Tell us WHY you shoot adapted!

billorg wrote:

Nothing like the feeling of my heavy LITTLE Zeiss rangefinder lenses in my hand!

Bill

Those older rangefinder lenses were all brass, weren't they? There really and truly is something about the weight of mechanical things, it feels as though it signifies quality.

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Lightshow
Lightshow Veteran Member • Posts: 7,614
Re: Tell us WHY you shoot adapted!

billorg wrote:

..
This thread: http://www.fredmiranda.com/forum/topic/969329 convinced me to buy a NEX camera.
I was looking for a good deal on a 5N when Sony announced the NEX-7, it had a built in EVF which I really wanted, then Steve Huff released his review with the hot-air balloon shot, I was sold, the NEX-7 would be my next camera.
I ended up with a NEX-7 that spring, I still wanted a FF camera, but could easily look past that due to the quality I was getting from it.
I was astounded by how easy it was to nail focus, if I wanted to place the plane of focus at the tip of something, I could, the 7 easily become my most favourite camera ever, after setting it up it was so intuitive to use, it could get out of my way in such a way that I could get into a creative zone of thought I had never experienced before, the subject was the only thing that existed, in a word... Nirvana.
I was immediately and vocally calling for a FF NEX-7, it took a few years for the A7 & A7r to be announced and I jumped for joy(sort of, the form factor was not the same), ahhh, at last, a FF sensor that wasn't so expensive and finally my legacy lenses that I was loving so much were now back to their original FOV, a 28mm lens wide again, cue the celebrations!

Never has it been better to be a photographer.

so great! I too love my NEX 5n, my thing is low noise at high iso, and only this one has held up over the years till Sony came out with the ff bodies. I use mine with the Zeiss rangefinder lenses and can also use Maxxum lenses, but the point of the NEX and the ting rangefinder lenses is the super small and elegant package that you can take anywhere. I have an 18 and 28mm so I can do great street scenes and landscapes without a worry about focus, since it’s pretty much infinity focus past a certain point. I use the focus peaking in yellow just to confirm. Tack sharp images! Bill

My favourite lens on my NEX-7 is my Leica M 28/2.8 v2, but even it is kinda big if I'm looking for absolute compactness, I modded an Industar 69 for infinity and on the NEX-7 it's not usable in colour(magenta along the short sides) so it's B&W only, it makes for a tiny B&W kit and higher ISO's provided a nice film like grain to the pictures, but I get bored with only B&W so I bought a Canon S 28/2.8 because the Canon S 35/2.8 worked so well on it, but it too had magenta issues 😩My A7r has the same issue with that lens, I think the BSI sensors have eliminated the issue, but I haven't tested the lens on one yet, someday. So my smallest lens without issues on the NEX-7 and A7r is the Canon S 35/2.8, I also like my Olympus Pen F 38/1.8 on the 7, it's almost the perfect size.

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Alan WF
Alan WF Veteran Member • Posts: 3,203
Re: OOF PSF
3

However, in conventional photography, I'm only aware of people regularly measuring very slightly OOF PSFs -- in a range where diffraction effects and differences in focus plane for different wavelengths dominate the structure. That seems to dominate the telescope usage as well, where most still seem to be in the range of seeing Airy discs.

I would agree that in-focus images dominate telescope usage, but out-of-focus images have been used for more than a century to diagnose aberrations and alignment.

Amateur astronomers will begin an observing session with a Newtonian telescope by observing the out-of-focus image of a bright star to confirm alignment. As a professional, I’ve done the equivalent dozens of times in my career. The infamous spherical aberration of the Hubble Space Telescope was first noticed by the old-time astronomer Earl O’Neil who, viewing through-focus images as they were transmitted down to NASA Goddard, said, “Something is not right”. Most modern profesional telescopes have wave-front sensors, which effectively use the out-of-focus image to measure the wave-front error over the telescope pupil. The standard text on astronomical optics has a chapter on diagnosing low-order aberrations on the form of the out-of-focus “donut”; a more modern treatment has extended this to higher-order aberrations.

I suspect photographic lens makers (but not users) will also look at the out-of-focus PSF too, again as a diagnostic tool.

I would venture that the reason the out-of-focus PSFs were not previously used similarly by users of photographic lenses is that there is nothing to adjust. If I notice that a typical two-mirror telescope if out of alignment (by examining out-of-focus images), then I can typically move the secondary mirror in both position and tilt to restore alignment. That will normally improve the in-focus image. I can’t do that in most (any?) photographic lenses.

In the Electronic Imaging community, looking at PSFs that are significantly OOFwas treated as pretty radical -- including by my friends at Imatest -- when I started pushing it as a primary metric in 2014. My use of OOF PSF dates from 2009. To this day, the vast majority of image processing software still models defocus as a Gaussian blur. You'd think at least the folks doing "Coded Aperture" work, which relies on being significantly OOF, would get this right, and they sort-of do, but all their aperture masks consist of square-pixel patterns for which the corners of the squares (and at lesser defocus, the squares themselves) cause diffraction effects.

You need to hang out with more optical engineers, although my experience is that you will need a strong liver.

Regards,

Alan

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Larry Rexley Regular Member • Posts: 466
Re: OOF PSF
2

Alan WF wrote:

However, in conventional photography, I'm only aware of people regularly measuring very slightly OOF PSFs -- in a range where diffraction effects and differences in focus plane for different wavelengths dominate the structure. That seems to dominate the telescope usage as well, where most still seem to be in the range of seeing Airy discs.

I would agree that in-focus images dominate telescope usage, but out-of-focus images have been used for more than a century to diagnose aberrations and alignment.

Amateur astronomers will begin an observing session with a Newtonian telescope by observing the out-of-focus image of a bright star to confirm alignment. As a professional, I’ve done the equivalent dozens of times in my career. The infamous spherical aberration of the Hubble Space Telescope was first noticed by the old-time astronomer Earl O’Neil who, viewing through-focus images as they were transmitted down to NASA Goddard, said, “Something is not right”. Most modern profesional telescopes have wave-front sensors, which effectively use the out-of-focus image to measure the wave-front error over the telescope pupil. The standard text on astronomical optics has a chapter on diagnosing low-order aberrations on the form of the out-of-focus “donut”; a more modern treatment has extended this to higher-order aberrations.

I suspect photographic lens makers (but not users) will also look at the out-of-focus PSF too, again as a diagnostic tool.

I would venture that the reason the out-of-focus PSFs were not previously used similarly by users of photographic lenses is that there is nothing to adjust. If I notice that a typical two-mirror telescope if out of alignment (by examining out-of-focus images), then I can typically move the secondary mirror in both position and tilt to restore alignment. That will normally improve the in-focus image. I can’t do that in most (any?) photographic lenses.

Regards,

Alan

As a 'former' professional astronomer who worked on a mountaintop observatory, and a long-time astrophotographer using both film and digital cameras, I can confirm the specific points Alan makes.

Conventional photographers are quite familiar with 'bokeh' --- and know full well that it varies greatly between lenses.  Well, bokeh is an out-of-focus image, although it is not always a point source.

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fferreres Veteran Member • Posts: 6,944
Re: Cost vs. modern lenses
1

ProfHankD wrote:

PhotosByHall wrote:

Finally it's no longer a cheap way to access great glass - every man and his dog is in on this now - some manual lenses cost more than their modern AF counterparts. If I am losing AF, I need to save $$$$.

Losing AF isn't something I generally view as a disadvantage if in trade I get smooth and precise manual focus... but I agree about cost for old vs. new lenses.

If the optical performance of an old lens and new one is similar, I expect to pay significantly less for the used lens... and perhaps even less if the used lens is pretty old. For example, I'll never understand why people spend more on a really poor quality old ultrawide than on a brand new lens that's optically much better.

Nostalgia, collectible (the reward of having something completed), rendering  which may be characterful, but also different colors and other properties.

Often times, it's more psychologically safe and rewarding to get a good picture with a poorer lens, than a poor picture with a good lens. Imperfections make things distinct, like Marylin Monroe. Few people fail to notice her (fake) mole.

Some aren't that bad, the trade off may be less cost effective. I like my 18/4 Zeiss a lot. Does images I really like.

fferreres Veteran Member • Posts: 6,944
Re: OOF PSF

From pure observation, the measuring the in focus PSF is more akin to competing in the Olympics. There is a rule, a measurement, and a possible comparison and winner given some metric. The OOF PSF is more like psychoanalysis. And optics is more like neurology or physiology.

The word Bokeh is so fruitless, it's almost like trying to describe colors and only having the word Not Black. Bokeh is everything that happens in absolutely almost every part of the photo, except when shooting a 2D target professionally.

I use the OOF PSF to rapidly psychoanalyze a lens. It is a characterization that varies non linearly, probably because most apertures are expressed at infinity, but at MFD other parts of the barrel may absorbing rays (lowering the effective aperture the closer one focuses) and other factors like it. And of course by aperture, we have a similar effect, and in any displacement away from the axis.

For example, aspects that seen an detect instantly are:

- What color just before and after focus, very comprehensive idea of LoCA profile

- Shape of edges and its color

- Shape of PSF itself ahead and behind the plane

- Shape change off axis for the above

Usually, one can see this and rapidly iterate the aperture, so instantly tells in which ways it does/does not improve

For example, the old very simple Elmar 50/3.5 has a noticeable outline at f3.5, very mild at f4, and gone at f6 or so. The shape of PSF is center weighted in the background in a particular, very very smooth way. It is better corrected than other lenses, so this center weight gets washed out much sooner than in others, meaning the bokeh will have very good definition within relative closeness to the plane, but after some point it acts more like a highly corrected lens. This and LoCA play a role in a perception during the transition zone (where features are medium frequency hard to recognize) making things there seem less saturated. Gives some vividness. I think this contributes to a more 3D impression. Red focuses a bit closer, certain "vine" green towards the background. They have similar OOF shapes by color (some lenses  have different OOF for red vs purple). Then, there are the casts, but this I don't follow much, but except relative to the whole picture. Can'tassess much here from the PSF because the camera WB is complex, and I don't know the profile of many many lights.

In some way, I can see some photos of the OOF PSP of some lenses, maybe a grid with one very far behind, two behind, one in focus, to ahead, on very close, and then to the sides, compete two to the left and to the right, and I can look into that, and get some idea of how the lens will render. It gives a very good sense. But no need to make the photos, this can be seen in maybe 3 mins. directly in the EVF. I am not sure if all these observations (for A7RIII) are data around 10 lp/mm to around 70 lp/mm. A 100MP camera would be able to observe closer to the peak focus plane. In many lenses, due to LoCA, the peak plane varies, depending on the colors of the subject, and sometimes it's hard to have one plane -a simple example is a label with leyends and tests printed in different colors.

I find it amusing to play Mr. Lens Freud, even if not perfect, it tells a lot, and can then be corroborated or "learned", how it looks in practice.

ProfHankD
ProfHankD Veteran Member • Posts: 8,060
Re: OOF PSF

Alan WF wrote:

I appreciate your insights on this; it seems telescope folks are always doing at least a little optical design & tuning that most of the world doesn't do....

However, in conventional photography, I'm only aware of people regularly measuring very slightly OOF PSFs -- in a range where diffraction effects and differences in focus plane for different wavelengths dominate the structure. That seems to dominate the telescope usage as well, where most still seem to be in the range of seeing Airy discs.

I would agree that in-focus images dominate telescope usage, but out-of-focus images have been used for more than a century to diagnose aberrations and alignment.

Amateur astronomers will begin an observing session with a Newtonian telescope by observing the out-of-focus image of a bright star to confirm alignment. As a professional, I’ve done the equivalent dozens of times in my career. The infamous spherical aberration of the Hubble Space Telescope was first noticed by the old-time astronomer Earl O’Neil who, viewing through-focus images as they were transmitted down to NASA Goddard, said, “Something is not right”. Most modern profesional telescopes have wave-front sensors, which effectively use the out-of-focus image to measure the wave-front error over the telescope pupil. The standard text on astronomical optics has a chapter on diagnosing low-order aberrations on the form of the out-of-focus “donut”; a more modern treatment has extended this to higher-order aberrations.

Again, at least as I read that, it is talking primarily about slightly OOF images with PSFs spread over relatively few pixels, not thousands to millions of pixels. No? You get very different information from very OOF PSFs....

I suspect photographic lens makers (but not users) will also look at the out-of-focus PSF too, again as a diagnostic tool.

Apparently not. The folks who make the test equipment and algorithms for them are regular attendees and exhibitors at Electronic Imaging, and OOF PSF were not measured by any of them. Most produce/use/light in-focus test charts, with a great deal of precision in handling color and contrast. I think there is a not-very-subtle distinction between testing of lenses and testing of camera systems, and most testing is system level. Certainly optical bench checks are done of lenses using equipment more like Roger Cicala's Olaf, but I don't know of any as careful as Roger... and it sounds like he doesn't think that's common either .

I would venture that the reason the out-of-focus PSFs were not previously used similarly by users of photographic lenses is that there is nothing to adjust. If I notice that a typical two-mirror telescope if out of alignment (by examining out-of-focus images), then I can typically move the secondary mirror in both position and tilt to restore alignment. That will normally improve the in-focus image. I can’t do that in most (any?) photographic lenses.

There are plenty of adjustable things in some lenses (as Roger has shown), but the trend definitely has been toward more design for tolerance ranges and less unit testing and individual adjustment. It's much cheaper that way now, especially with different subcontractors making various parts.

A lot of older lenses that don't seem adjustable are in fact adjustable (or at least were adjusted at assembly time) -- for example, many locking rings on elements still allow the element to be locked in place with slight tilts or shifts and not having specialized equipment to do element-level alignment makes this a key reason why I try not to disassemble lenses any more than necessary....

In the Electronic Imaging community, looking at PSFs that are significantly OOFwas treated as pretty radical -- including by my friends at Imatest -- when I started pushing it as a primary metric in 2014. My use of OOF PSF dates from 2009. To this day, the vast majority of image processing software still models defocus as a Gaussian blur. You'd think at least the folks doing "Coded Aperture" work, which relies on being significantly OOF, would get this right, and they sort-of do, but all their aperture masks consist of square-pixel patterns for which the corners of the squares (and at lesser defocus, the squares themselves) cause diffraction effects.

You need to hang out with more optical engineers, although my experience is that you will need a strong liver.

I have tried to, but I honestly have had a lot of trouble finding them... and I'm a lifetime member of SPIE (the international society for optics and photonics) and a member of IS&T (Society for Imaging Science and Technology, which runs Electronic Imaging).

In the Physics department at the University of Kentucky, there are lots of people working with things like gravitational lensing, but nobody who works on "conventional" optical design. CeNSE, the Center for Nanoscale Science and Engineering , is run by folks in my department, and Todd Hastings (the director of CeNSE) actually does quite a bit of lens design and fabrication, but that's not the types of lenses you'd use on a regular camera either. The closest I've come is a bunch of work I did two decades ago with Jan Allebach at Purdue, where I helped him use my supercomputing facilities for design of diffractive optics (DO) using variations on his DBS (direct binary search) algorithm.

My impression is that lens design is now largely viewed as relatively straightforward application of design tools like Zemax to tweak existing designs and not a research field. Personally, I'm pretty sure that there are many advancements to be made in lens design (especially in things like design and use of true DO elements), but I haven't seen it in academia. The most innovative optical design for cameras that I've seen in the last two decades was Brian Caldwell's insights applying focal reducers (which I know have long been common in the telescope world) to conventional camera optics for APS-C sensors.

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ProfHankD
ProfHankD Veteran Member • Posts: 8,060
Re: Cost vs. modern lenses

fferreres wrote:

ProfHankD wrote:

PhotosByHall wrote:

Finally it's no longer a cheap way to access great glass - every man and his dog is in on this now - some manual lenses cost more than their modern AF counterparts. If I am losing AF, I need to save $$$$.

Losing AF isn't something I generally view as a disadvantage if in trade I get smooth and precise manual focus... but I agree about cost for old vs. new lenses.

If the optical performance of an old lens and new one is similar, I expect to pay significantly less for the used lens... and perhaps even less if the used lens is pretty old. For example, I'll never understand why people spend more on a really poor quality old ultrawide than on a brand new lens that's optically much better.

Nostalgia, collectible (the reward of having something completed), rendering which may be characterful, but also different colors and other properties.

Predictable "unusual" properties can be used to make art, but that makes the lens harder, not easier, to use well....

Often times, it's more psychologically safe and rewarding to get a good picture with a poorer lens, than a poor picture with a good lens. Imperfections make things distinct, like Marylin Monroe. Few people fail to notice her (fake) mole.

Lowered expectations make for happier people? Could be....

For me, a lens with a very distinctive rendering is a dangerous tool: if one isn't careful, all people will see is the mole, and not the woman nor the scene she's part of. 

Some aren't that bad, the trade off may be less cost effective. I like my 18/4 Zeiss a lot. Does images I really like.

That is a very highly-rated lens, although it isn't cheap.

Nearly all old ultrawides are relatively bad if you do side-by-side comparisons with modern optics. That said, my Mir 20 (20mm f/3.5) is actually pretty good as a FF optic... and mine only cost me $10, so it easily beats any modern lens at that price point.   It's also true that many ultrawides are now zooms, and a modern ultrawide zoom against and old ultrawide prime can be a much closer race.

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AudiiDudii
AudiiDudii Contributing Member • Posts: 676
Re: Tell us WHY you shoot adapted!
2

billorg wrote:

Is it more because you like to "make do" with what you have, OR you like to buy less expensive lenses for cameras you already have OR do you buy expensive new cameras or lenses because you are searching for that holy grail combination of best lens coupled with the best sensor? Or maybe another reason?

First and foremost, I adapt lenses so I can use them in ways not intended by the original designer / manufacturer, which means with in-camera rise / fall movements. This way, I convert every lens I own into a tilt/shift lens and I am not limited to only choosing from the handful of focal lengths spec'd by lens manufacturers.

Secondly, I'm very much a "frugalitarian," in that I enjoy doing more with less. Yes, there are times when throwing money at a problem is clearly the best solution -- and I will do it when I have no other means to achieve the result I desire -- but there's a lot of enjoyment to be had from turning a pig's ear into a silk purse and especially so if you do all the work yourself for not a lot of money.

Finally, although I consider myself to be a documentary photographer, I prefer a pleasing character over unforgiving accuracy when it comes to how a lens condenses the scene in front of it from three dimensions into just two. (For similar reasons, I prefer a seductive girlfriend, who overlooks my flaws or considers to be them strengths, to a nagging wife, who reminds me regularly -- and in all fairness, accurately! -- of the many, many ways in which I fall short of perfection ... again. <sigh>)

But this is just me and YMMV!

Eggplantt
Eggplantt Forum Member • Posts: 98
Re: The joy of manual focus, Noah's Ark

The overarching reason is that you obtain something that isn't otherwise conveniently accessible with your current camera system. The reasons for this include

  1. Price- ignoring quality, you can get comparable lenses in terms of zoom range/low light/macro capabilities etc cheaper
  2. Supply- there just isn't enough of a lens designed for your camera available on the market to buy
  3. Specifications- certain focal length(s), certain aperture, certain constant aperture, build quality, weight, size, aperture half stops, declicked or declickable aperture, long focus throw, filter size, drop-in filter support, built-in hood, minimum aperture, focus limiter etc; combination of all these factors at once.
  4. Performance- in terms of correcting abberations. Sharpness across the frame, contrast, distortion, chromatic abberating, vignetting, etc all of this wide open and how much you need to stop down to see improvement
  5. Performance- in terms of entirely subjective features such as bokeh 'behaviour', transition from focus to out of focus areas, colour rendering, sunstars, bokeh shape as a result of aperture blades, their number and curvature etc. Things like vignetting are subjective, but far far less so than these features

These reasons don't address the other motive from being a hobbyist, collector, enjoyer of vintage items, optical design enthusiast, nerd etc

ProfHankD wrote:

In part, I deliberately try to cycle through to remain aware of what each can do, but it's really like having a large, well curated, wine cellar from which I can pick the most suitable accompaniment for any particular dish I want to make -- be it photography for research, personal, or art purposes.

This best explains my interest, if not literally as I seek out optical surplus that was once (and still is) very advanced and fiendishly expensive, like a fine wine.

That's half the fun of optics, or optomechanics- as simple and in high demand as the wheel, in a mature state of knowledge for centuries, with a very high turnover of advanced stuff dumped on auction sites with probably no buyer for years, ripe for you to get use out of.

In closing, I think it's also useful to point-out just how much more one can get from a lens by using as much as possible of its high-quality image circle.

However, I have to admit that the 44x33mm sensors in the Fuji GFX models are probably even better at getting what most designed-for-FF lenses have to offer; most FF lenses can cover significantly more than 36x24mm (although few give high-quality coverage of 44x33mm).

Just double checking here- I assume you test these at minimum apertures like f16? I have a handful of 35-70mm zoom lenses that wide open would do 645... but that's sadly not indicative.

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trungtran Senior Member • Posts: 1,533
Re: Tell us WHY you shoot adapted!
2

It started with a challenge to produce high quality pictures with the cheapest gear.

It is now the flexibility of using one lens on multiple formats for different framing.

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fferreres Veteran Member • Posts: 6,944
Re: Tell us WHY you shoot adapted!

AudiiDudii wrote:

billorg wrote:

I prefer a seductive girlfriend, who overlooks my flaws or considers to be them strengths

The power of imagination. Let me know when you find that and if you do, I need some tips.

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