45 macro portrait shots

Started Nov 23, 2009 | Discussions
kenw
kenw Veteran Member • Posts: 5,385
Wait, I don't understand this...

Godfrey wrote:

In macrophotography, a magnification is a magnification. "Equivalent magnification" is meaningless... 1:1 is not 1:2.

Maybe I'm missing what you are saying here, but what I'm reading doesn't make much practical sense. I'm trying to make an image, I don't care what my sensor size is, I care what my final print is. So, I want a quarter to fill the frame and on 35mm that will require a lens that can do 1:1. On m43 I can get away with 1:2 and get the same result. I understand that the numbers behind reproduction ratio don't change (the same way focal length doesn't change when you put a lens on a different format camera). In its essence though, in the manner that it matters to a photographer, a 1:2 macro lens on m43 is in fact very much like a 1:1 lens on 35mm.

Am I misunderstanding something here?
--
Ken W

Rebel XT, XTi, Pany G1, LX3, FZ28, Fuji F30, and a lot of 35mm and 4x5 sitting in the closet...

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PhillipA Veteran Member • Posts: 5,505
It seems a lot of posters here have ...

.. a "budget" mentality. Look at most other systems and $800 isn't much to pay for even a quite modest lens, yet many here are taking the position that you can buy something similar for less money, so the Panasonic must be a "rip-off". As Godfrey pointed out - there are no other lenses at the moment that will do the same job as the Panasonic 45 macro - i.e. A/F on Panasonic bodies and has IS. Comparable lenses from the 2 major manufacturers are more expensive, with the Canon 100 f2.8 IS being $1050 and the Nikon 105 f2.8 VR being $890. Canons 180 macro is over $1400 and Nikons 200 is $1650. There are plenty of other examples of comparable lenses with different features being vastly different in price: Canon's 85 f1.8 prime being exceptionally sharp and $380 while the 85 f1.2 is $1840. Once again Canon's 70-200 f4 zooms are $650 without IS and $1190 with IS. The f2.8 version is $1290 without IS and $1900 with IS. Being asked to pay around $800 for the one lens that will do a specific job on a particular brand of camera, and do it well, is small change in this day and age.
--

Judge: ' This image may be better in black and white - perhaps even just black! '

kenw
kenw Veteran Member • Posts: 5,385
Very interesting...

So, if I can try to paraphrase (and hopefully not mess up in the process) you are saying that for most wide-angle to normal focal ranges in this format the exit pupil is actually typically at the same distance regardless of focal length because of the optics designs employed and thus the airy disk tends to be more closely proportional to physical aperture rather than numerical aperture in this range?

I can certainly imagine a focal range of near constant exit pupil distance on the wide angle end being necessary for the IR filter and microlenses - we seem to have plenty of evidence of the m43 sensors not being happy with RF lenses that have exit pupils very close to the sensor...

Really interesting observation, thanks for posting it. I have to mull it more to fully process.
--
Ken W

Rebel XT, XTi, Pany G1, LX3, FZ28, Fuji F30, and a lot of 35mm and 4x5 sitting in the closet...

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Jonas B Forum Pro • Posts: 14,596
Re: f-stop, not absolute opening, decides diffraction

Godfrey wrote:

Ehrik wrote:

f/11 isn't anywhere near the diffraction limit for a 50mm lens. That's a 4.5mm opening. Diffraction sets in nearer a 2.5mm and smaller lens opening.

Godfrey, this is one of the rare occasions when you are mistaken on a technical/theoretical matter.

The absolute opening size (entry pupil) is not the deciding factor, it is the f-stop. Thus, any lens will have the same amount of diffraction at f/11. It doesn't matter what the focal length is.

I disagree.
(...)

This is something I hear all the time. I was always disturbed by this statement as it didn't match my observations of diffraction degradation. So I did my own testing ...

I have also done my own testing. Not with the Panasonic 45mm macro, but with the ZD50/2 Macro. My test was as usual done at a distance of 55xFL and can be described in detail for anyone to repeat.

The resolution clearly decreases before f/11. The lens peaks at f/4-f/5.6 and then the values drops. This can also be seen in the review of the lens here at DPR (which you probably haven't read). It is probably the same with the Panasonic macro.

I have limited experience from real macro work. To my understanding the macro people are more or less all the time working beyond what is called "diffraction limit" as they are looking for a wide DOF. The images doesn't seem to suffer a lot from this.

I have this idea about lenses and diffraction; the better, or closer to optically perfect, a lens is, the earlier we can see the effect from diffraction. Earlier in this case is closer to wide open. The theory is that problems caused by diffraction most often are masked by other aberrations at large aperture openings. I could see this when "testing" my Leica APO Elmarit-R 100/2.8 Macro.

Jonas

Cameraman777 Forum Member • Posts: 97
Current price reflects high demand and low supply

Remember the current street price is the "list" price reflecting the high demand and low supply, typically associated with a new product rollout - hey the G1/GF1/GH1 after all are a highly successful new product family.

I believe the street price will drop to around $620 after the new year. Again my BIG PROBLEM is that I can't wait, and will be happy to pay the list price if available in USA, or pay slightly higher than the list price to buy from Japan, as one poster suggested.

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Panasonic LX100
Godfrey Forum Pro • Posts: 29,443
Re: Wait, I don't understand this...

kenw wrote:

Godfrey wrote:

In macrophotography, a magnification is a magnification. "Equivalent magnification" is meaningless... 1:1 is not 1:2.

Maybe I'm missing what you are saying here, but what I'm reading doesn't make much practical sense. I'm trying to make an image, I don't care what my sensor size is, I care what my final print is. So, I want a quarter to fill the frame and on 35mm that will require a lens that can do 1:1. On m43 I can get away with 1:2 and get the same result. I understand that the numbers behind reproduction ratio don't change (the same way focal length doesn't change when you put a lens on a different format camera). In its essence though, in the manner that it matters to a photographer, a 1:2 macro lens on m43 is in fact very much like a 1:1 lens on 35mm.

Am I misunderstanding something here?

I'm not talking about pictorial photography here, where the goal is to make a pleasing photograph and you're looking for some approximate framing to make a print from. I'm talking about technical or forensic macrophotography where the goal is to record and collect accurate data about small scale subject matter in the 1:5 to 3:1 magnification range, suitable for measurement and investigation.

My background in macrophotography was documenting instrumentation and components for remote sensing equipment. When I set up to record components and document fractures, etc, the dimensions of the imaged subject on the recording medium the primary importance to the work. If the subject matter was 15x15 mm in size, and I was working with a 35mm Film SLR (Nikon F3), I needed to image the subject at 1:1 so that we could do accurate measurements on the recorded image and translate that to mm or thousands of an inch dimensions.

Nothing about the output (print size, projection corrections, etc) influenced what I needed to do in capture to obtain a known accurate representation suitable for measurement. That's what 1:1, 1:2, 2:1, etc are all about when you talk about a macro lens being able to achieve a particular magnification ratio. The fact that a FourThirds field of view at 1:2 magnification is an approximate match to the 35mm Film format's 1:1 field of view isn't relevant to macrophotography. (They deviate quite a lot, actually, since the format proportions are dissimilar rectangles.)

In a digital domain, knowing that I have an accurate, specific capture magnification means that I can measure the subject matter precisely in pixel dimensions from the capture (way more accurate to measure on a computer screen than to use a magnifying loupe with scale on film!) and translate that to extremely accurate physical dimensions. Whether that subject field is "comparable" to a different magnification capture for a different format is completely irrelevant.

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Godfrey Forum Pro • Posts: 29,443
Re: Very interesting...

kenw wrote:

So, if I can try to paraphrase (and hopefully not mess up in the process) you are saying that for most wide-angle to normal focal ranges in this format the exit pupil is actually typically at the same distance regardless of focal length because of the optics designs employed and thus the airy disk tends to be more closely proportional to physical aperture rather than numerical aperture in this range?

I can certainly imagine a focal range of near constant exit pupil distance on the wide angle end being necessary for the IR filter and microlenses - we seem to have plenty of evidence of the m43 sensors not being happy with RF lenses that have exit pupils very close to the sensor...

Really interesting observation, thanks for posting it. I have to mull it more to fully process.

Yes, that is my hypothesis. And my test evidence seems to support it.
--
Godfrey
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kenw
kenw Veteran Member • Posts: 5,385
Re: Wait, I don't understand this...

Fair enough Godfrey, but I don't think the poster you were responding to or nearly anyone else on this board is coming from the context of measuring an item on negative or transparency. Furthermore I don't know what you are on about with "precision" and "approximate", you are going to have to calibrate any optic and digital sensor you use with a known standard prior to doing any analysis anyway.

The photographers here want a bug to fill the frame. And in that context the same way most photographers are used to thinking of a 14mm m43 lens being like a 28mm FF lens it is fair to say a 1:2 m43 macro lens is like a 1:1 FF lens. I think that is the context people are coming from and why I think your comment "meaningless" might be a bit of hyperbole or perhaps based primarily on your past use experience rather than the common use in this context.

And, really, the subject you describe (precision measurement) would use a double telecentric lens design and not a consumer m43 macro lens!
--
Ken W

Rebel XT, XTi, Pany G1, LX3, FZ28, Fuji F30, and a lot of 35mm and 4x5 sitting in the closet...

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Ehrik Veteran Member • Posts: 8,014
Re: f-stop, not absolute opening, decides diffraction

Godfrey wrote:

Ehrik wrote:

f/11 isn't anywhere near the diffraction limit for a 50mm lens. That's a 4.5mm opening. Diffraction sets in nearer a 2.5mm and smaller lens opening.

Godfrey, this is one of the rare occasions when you are mistaken on a technical/theoretical matter.

The absolute opening size (entry pupil) is not the deciding factor, it is the f-stop. Thus, any lens will have the same amount of diffraction at f/11. It doesn't matter what the focal length is.

I disagree.

From
-
http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm

Technical Note:

Since the physical size of the lens aperture is larger for telephoto lenses (f/22 is a larger aperture at 200 mm than at 50 mm), why doesn't the size of the airy disk vary with focal length?  This is because the distance to the focal plane also increases with focal length, and so the airy disk diverges more over this greater distance.   As a result, the two effects of physical aperture size and focal length cancel out.  Therefore the size of the airy disk only depends on the f-stop, which describes both focal length and aperture size. ...

Just noting that the above quote is in agreement with what I stated.

This is something I hear all the time. I was always disturbed by this statement as it didn't match my observations of diffraction degradation. So I did my own testing ...

Well, how do you separate diffraction blur from lens aberrations? I don't think you are testing what you think you are testing.

The reason this is not entirely correct is that the statement of independence of focal length to diffraction limits is based on the notion that as lens focal length increases, the exit pupil and Airy disk is projected onto the sensor at a greater distance. HOWEVER, for lenses in the focal length range that I use, and that we're discussing here (7 to 70 mm on FourThirds DSLR and micro-FourThirds bodies), the lens designs are such that the projection is not so much different in terms of total distances as it would be for much longer focal lengths (> 100mm). The statement above is correct for the case of symmetric and mild telephoto lenses of varying focal lengths ... but we are not dealing with the case of symmetric lenses in this range, on these cameras, we're working mostly with inverse telephoto designs for the most part.

The lens' design does not factor into it. This isn't about optics as much as it is about physics, propagation of waves.

I tested my theory some time ago after reading about this notion of the independence of focal length from diffraction limits, and found what I suspected was true. In the range of focal lengths we're discussing here, diffraction degradation of image quality followed a general rule of starting when the iris opening reduced to less than approximately 2.5 mm.

Are you talking about the physical diameter of the opening between the aperture blades inside the lens?

This value changes a bit depending upon the particular lens design you're working with, as well as the other factors as mentioned in the rest of the above article.

I assure you that if you fit a ZD 11-22/2.8-3.5 lens onto your G1 and observe the behavior of a slit test for each focal length setting at all f/stops, you'll see diffraction begin earlier at 11mm than it does at 22mm (approximately f/4.5-5.5 vs f/8-9), and likewise for a 14-45 mm.

When you begin to see a certain amount of diffraction, or put another way, at what aperture the resolution peaks, depends also on the aberrations of the lens. An excellent lens will peak at a larger aperture (smaller f-number) than a less good lens which needs stopping down more, but this is not because there is any difference in the diffraction at the same f-stop between the lenses.

A 45-200 mm lens, on the other hand, this starts to level out as the lens design and telescoping of the optics levels out the interaction of Airy disk and focal length.

I realize that my notions here run counter to the current popular wisdom

It's rather science than popular wisdom.

but I'm satisfied that my observations of the behavior of diffraction provides empirical evidence of their validity.

You need to interpret the results from your tests correctly.

Correct me if I am wrong, but aren't some saying that the 1:2 ratio of the Oly lens is in fact equivalent to 1:1 on 35mm full frame, and that the 1:1 of the Pannyh Leica is really a super duper ratio. If so, could we not call it a draw in that Oly haven't given anything that is "less than".

In macrophotography, a magnification is a magnification. "Equivalent magnification" is meaningless... 1:1 is not 1:2.

I disagree that it is meaningless. Placing more pixels on the subject is desirable.

But this is more of a system/sensor factor.

I do not understand your meaning. [snipped for char limit]

If you have a 12Mp 4/3" sensor and a 12Mp FF sensor, and use sharp lenses at 1:1 on both, a subject that fills the frame (uses 12Mp) on the 4/3" sensor will only use ~3Mp on the FF, so the 4/3" camera will place more pixels on the subject, give more detail and thus allow a larger magnification without visible pixelation when viewing.

Because of this, I think it is meaningful to have a concept of "equivalent magnification" just as we can talk about a 200mm lens on 4/3" having an equivalent FOV of a 400mm lens.

It's okay for you to disagree on this usefulness. This particular point isn't about physical facts.

kenw
kenw Veteran Member • Posts: 5,385
No, on 2nd thought have to side with Ehrik...

Very interesting theory, almost had me, but upon further reflection and research it's one of those things that sounds good but doesn't match my (perhaps flawed or limited) understanding of physics and optics. Exit pupil distance or other optics magic doesn't effect the airy disk in the projected image.

Furthermore, it doesn't match a huge database of measurements I have right here at my fingertips on DPR! Just looked at every single lens in m4/3 and 4/3 well into diffraction limit (F/22) and they all tightly cluster on 750lp/ph for every single lens at every single focal length. If your theory regarding exit pupil distance, non-symmetric or reverse telephoto designs was sound the Airy disk (a.k.a. the F/22 resolution) would vary between lenses and focal lengths. It doesn't, across focal ranges from 9mm to 140mm and eleven tested lenses.

I completely understand and do not doubt your data that some lenses you measured have peak resolution apertures that differ based on focal length. But as Ehrik said you are measuring aberrations there, not diffraction. Diffraction is solely dependent on numerical aperture (unless of course you've got metamaterial with a negative refractive index lying about).

Oh, and as far as the lens in question (the 45) the DPR tests show its peak resolution at somewhere near F/6.3 which is just about the same as both the 14-45 and 14-140 across almost all their focal lengths.
--
Ken W

Rebel XT, XTi, Pany G1, LX3, FZ28, Fuji F30, and a lot of 35mm and 4x5 sitting in the closet...

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Godfrey Forum Pro • Posts: 29,443
Re: f-stop, not absolute opening, decides diffraction

Ehrik wrote:

You need to interpret the results from your tests correctly.

Your lack of faith disturbs me, young Skywalker. LOL!!!

I'm quite confident I know what I'm doing when I test things like this, Ehrik. I don't question your competence; it would be pleasant of you to understand that I know what I'm doing too. We've had enough conversations I think some trust in my credibility is warranted. If you don't feel the same way, well, that's the end of the discussion.

If you have a 12Mp 4/3" sensor and a 12Mp FF sensor, and use sharp lenses at 1:1 on both, a subject that fills the frame (uses 12Mp) on the 4/3" sensor will only use ~3Mp on the FF, so the 4/3" camera will place more pixels on the subject, give more detail and thus allow a larger magnification without visible pixelation when viewing.

That's a peculiarly circuitous way to think of this, Ehrik.

If you have a 12 Mpixel 24x36 mm sensor, and a 12 Mpixel 13x17.3 mm sensor, and you record a subject with each at 1:1 magnification, you're going to get 12 Mpixels of information from both but the imaged field will be 864 mm^2 for the 24x36 case and 225 mm^2 for the FourThirds case ... about 4x the area. In linear terms, that's 2x as many pixels per mm on the FourThirds sensor but of 1/4 the subject ... 2x more linear resolution. IN this one, specific case ...

To me it's useless, academic kaka. We have FourThirds cameras with 5, 7.5, 8, 10 and 12 Mpixel resolutions, and with varying antialiasing filters which affect their acutance. We have "full frame" cameras with anywhere from 8 to 24 Mpixels available and with differing acutance as well. For each case, specific camera to camera, these equivalences are going to slide around based on the realizable pixel resolutions AND format size. I'm pretty sure that's not what Olympus had in mind given that they always stated "1:2 FourThirds equivalent to 1:1 in 35mm Film." If either kind of "equivalence" is useful to someone who already owns a FourThirds camera and is looking to buy a macro lens, I'd love to know why. It seems to me nothing more than a marketing way of promoting some kind of FourThirds advantage.

In doing macro work, I need to know recording medium dimensions, resolution, and magnification ratio. That gives me all the information I need to interrogate the subject and derive all the information I need regards dimensions of the subject, etc, with a given camera.

The only case where an "equivalent" from one camera/format/lens to another isn't completely superfluous is when I am researching what camera to buy to do my data collection with. At which point I need to do the math for each camera I'm considering (and likely some testing to determine acutance as well).
--
Godfrey
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Godfrey Forum Pro • Posts: 29,443
Re: No, on 2nd thought have to side with Ehrik...

Could be.

But, as always, I trust what I measure and demonstrate through my experiments and testing more than I trust someone else's numbers that I have incomplete information as to how and what they used to generate them.

I don't really care if I'm wrong or right, actually. All I know is that what I've done has proven, in practice, to produce the results I want. It's that 'power of first hand experience' thing ... ];-)
--
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Godfrey Forum Pro • Posts: 29,443
Re: Wait, I don't understand this...

kenw wrote:

... The photographers here want a bug to fill the frame. ...

Sadly true. All they really need is a close up lens in most cases, not a hot-shot macro lens.

And, really, the subject you describe (precision measurement) would use a double telecentric lens design and not a consumer m43 macro lens!

It would be wonderful if when I was doing this the more specialized, "right" equipment was available. We used a lot of off the shelf lenses and built our own jigs because it was available, expedient and cheap ... a double telecentric lens built for the job was never available, and too expensive to requisition for the amount of use we'd get out of it. A Micro-Nikkor 55mm f/3.5 AI-S and Micro-Nikkor 200mm f/4 ED IF AI-S was as specialized and pro as I had to work with.

I find the "2x crop factor" stuff to be similarly meaningless, btw. As I think I've mentioned before. I've used multiple formats my entire life and never went into this "equivalent this and that" stuff ever until digital cameras happened along. It always irks me as it muxes up the discussion.
--
Godfrey
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Jonas B Forum Pro • Posts: 14,596
Re: No, on 2nd thought have to side with Ehrik...

Godfrey wrote:

Could be.

But, as always, I trust what I measure and demonstrate through my experiments and testing more than I trust someone else's numbers that I have incomplete information as to how and what they used to generate them.

I don't really care if I'm wrong or right, actually. All I know is that what I've done has proven, in practice, to produce the results I want. It's that 'power of first hand experience' thing ... ];-)

My first hand experience, as mentioned above is illustrated here:

A test strip once made for JK at Oly SLR forum, who like many other pays too much attention to SLRGear blur units, thinks lenses can be compared between systems and claimed the ZD50/2 is free from diffraction.

What do we see here if not diffraction?

Jonas

Ehrik Veteran Member • Posts: 8,014
Re: f-stop, not absolute opening, decides diffraction

Godfrey wrote:

Ehrik wrote:

You need to interpret the results from your tests correctly.

Your lack of faith disturbs me, young Skywalker. LOL!!!

I'm quite confident I know what I'm doing when I test things like this, Ehrik. I don't question your competence; it would be pleasant of you to understand that I know what I'm doing too. We've had enough conversations I think some trust in my credibility is warranted. If you don't feel the same way, well, that's the end of the discussion.

So, help me, how do you interpret these results:

I assure you that if you fit a ZD 11-22/2.8-3.5 lens onto your G1 and observe the behavior of a slit test for each focal length setting at all f/stops, you'll see diffraction begin earlier at 11mm than it does at 22mm (approximately f/4.5-5.5 vs f/8-9), and likewise for a 14-45 mm.

One bit that was left hanging:

In the range of focal lengths we're discussing here, diffraction degradation of image quality followed a general rule of starting when the iris opening reduced to less than approximately 2.5 mm.

Are you talking about the physical diameter of the opening between the aperture blades inside the lens?

You didn't answer this one, but for the benefit of other readers, let me point out that the physical iris size is rarely interesting. The aperture is the apparent opening as seen from the front of the lens. Thus the glass in front of the iris comes into play.

Regarding the equivalent magnification discussion, I agree that if sensors have different pixel counts, this has to be accounted for. This is a point I've made a few times regarding Oly's claim about having smaller (equivalent FOV) tele lenses. This is in conflict with their statement that "12 Mp is sufficient" (or something of that meaning). With the Canon 7D matching the pixel density of 4/3" it may be advisable to offer a higher Mp 4/3" body for the birders.

And the same reasoning goes for macro as for tele.

kenw
kenw Veteran Member • Posts: 5,385
Re: Wait, I don't understand this...

Godfrey wrote:

I find the "2x crop factor" stuff to be similarly meaningless, btw. As I think I've mentioned before. I've used multiple formats my entire life and never went into this "equivalent this and that" stuff ever until digital cameras happened along. It always irks me as it muxes up the discussion.

Completely on board with you there. I don't know who first coined the term "crop factor" but I'm sure they thought they were doing people a favor - how's that go, "the road to hell is paved with good intentions" :).

Oh, and trust me, I know all about jury-rigged macro setups. A number of years in a university MEMS lab (micro-machining for those not writing for DARPA grants) resulted in many an act abhorrent to the optics gods. In general I was just happy if the silane didn't leak and explode...

Anyway, regardless of nit-picking over terminology, thanks again for your always informative and thought provoking posts...
--
Ken W

Rebel XT, XTi, Pany G1, LX3, FZ28, Fuji F30, and a lot of 35mm and 4x5 sitting in the closet...

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plevyadophy Veteran Member • Posts: 4,258
Explained at last!! Re: Wait, I don't understand this...

Godfrey wrote:

kenw wrote:

Godfrey wrote:

In macrophotography, a magnification is a magnification. "Equivalent magnification" is meaningless... 1:1 is not 1:2.

Maybe I'm missing what you are saying here, but what I'm reading doesn't make much practical sense. I'm trying to make an image, I don't care what my sensor size is, I care what my final print is. So, I want a quarter to fill the frame and on 35mm that will require a lens that can do 1:1. On m43 I can get away with 1:2 and get the same result. I understand that the numbers behind reproduction ratio don't change (the same way focal length doesn't change when you put a lens on a different format camera). In its essence though, in the manner that it matters to a photographer, a 1:2 macro lens on m43 is in fact very much like a 1:1 lens on 35mm.

Am I misunderstanding something here?

I'm not talking about pictorial photography here, where the goal is to make a pleasing photograph and you're looking for some approximate framing to make a print from. I'm talking about technical or forensic macrophotography where the goal is to record and collect accurate data about small scale subject matter in the 1:5 to 3:1 magnification range, suitable for measurement and investigation.

My background in macrophotography was documenting instrumentation and components for remote sensing equipment. When I set up to record components and document fractures, etc, the dimensions of the imaged subject on the recording medium the primary importance to the work. If the subject matter was 15x15 mm in size, and I was working with a 35mm Film SLR (Nikon F3), I needed to image the subject at 1:1 so that we could do accurate measurements on the recorded image and translate that to mm or thousands of an inch dimensions.

Nothing about the output (print size, projection corrections, etc) influenced what I needed to do in capture to obtain a known accurate representation suitable for measurement. That's what 1:1, 1:2, 2:1, etc are all about when you talk about a macro lens being able to achieve a particular magnification ratio. The fact that a FourThirds field of view at 1:2 magnification is an approximate match to the 35mm Film format's 1:1 field of view isn't relevant to macrophotography. (They deviate quite a lot, actually, since the format proportions are dissimilar rectangles.)

In a digital domain, knowing that I have an accurate, specific capture magnification means that I can measure the subject matter precisely in pixel dimensions from the capture (way more accurate to measure on a computer screen than to use a magnifying loupe with scale on film!) and translate that to extremely accurate physical dimensions. Whether that subject field is "comparable" to a different magnification capture for a different format is completely irrelevant.

Yippee!

Now I understand what you mean

It would have been better if you had explained it so well earlier on, instead of leaving it hanging in the air and expecting us to have something akin to religious faith that what you say is corrrect (a la your earlier remark to Ehrik re simply trusting you)

Explained the way you have just explained it makes perfect (and rather pedantic ) sense (has added to my education, and jogged my memory about things I learnt and had to do years ago).

Regards,

Ehrik Veteran Member • Posts: 8,014
Size correlates to manufacturing cost

PhillipA wrote:

.. a "budget" mentality. Look at most other systems and $800 isn't much to pay for even a quite modest lens,

... with, I think you'll find, quite a lot of optical glass used

yet many here are taking the position that you can buy something similar for less money, so the Panasonic must be a "rip-off".

The thing is that when studying lenses and prices a clear picture emerges of the amount and size of optical glass used being perhaps the single most important factor for the manufacturing cost.

By using a sensor that's half the diagonal of FF, Panasonic have allowed themselves to design lenses that have to be a lot cheaper to make than lenses for FF with the same FOV and f-number.

What some people are lamenting is that Panasonic seem to pocket all the difference!

I fully understand that they want to, since they are there to make as much profit as possible and their impressive innovation has given them the enviable position of a hot market all for themselves (and Oly). As long as they sell as many as they can make, and there is no competition, there is little reason from their POV to lower the prices.

But you have also got to understand that not everyone is happy to see margins that likely are many times bigger than what is normal for the industry.

Comparable lenses from the 2 major manufacturers are more expensive, with the Canon 100 f2.8 IS being $1050 and the Nikon 105 f2.8 VR being $890. Canons 180 macro is over $1400 and Nikons 200 is $1650.

And they all use vastly more glass in order to offer up to 10x more aperture area and gather up to 4x more light than the PL45.

There are plenty of other examples of comparable lenses with different features being vastly different in price: Canon's 85 f1.8 prime being exceptionally sharp and $380

I bought mine used for a mere €250.

while the 85 f1.2 is $1840.

It's also two and half times heavier and has much larger front element.

Once again Canon's 70-200 f4 zooms are $650 without IS and $1190 with IS.

This is an example of the manufacturer likely using lack of competition to get an extra big margin. It's part of why Canon and Nikon are unwilling to offer sensor IS. This pricing is also something people express dissatisfaction with, especially compared to DSLRs with sensor IS. And I don't blame them.

Jonas B Forum Pro • Posts: 14,596
And another illustration

...for those liking charts and numbers more than real images:

The series of images for the chart above was taken at about 40xFL and with a multi target made for checking the macro contrast of some lenses - that's an entirely other discussion but among the targets there was an IMA B&W test target placed a bit over the center of the image, approx at a position where the eyes would be if it had been a head and shoulder portrait.

I still interpret the lowered IQ at smaller aperture openings as something due to diffraction.

Jonas

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