Performance of a much more expensive lens

SonyX wrote:

faunagraphy wrote:

rich_cx139 wrote:

faunagraphy wrote:

<snip>

Great. That photo demonstrates the disadvantage of a bigger sensor perfectly. The DOF is so shallow that there is no feather detail on the wings whatsoever. Only the eyes have detail on them. It starts getting blurry near the neck and on the wings it looks like a watercolor painting.

To get more DOF you'd have to stop it down by 2 or 3 stops, which makes matters worse in poor light, like when that photo was taken.

... and by the time you have stopped down 2 on a FF from 2.8 to 5.6, say, then you are at roughly the same low noise ISO situation as you have with m43 at f2.8. Except, of course that an em1.2 or 1.3 is about 1 1/3 not 2 stops behind a general FF sensor.

Exactly. James Stirling, SonyX - are you reading?

This chart from DXOMark fools a lot of people. Their testing methodology attempts to measure a saturation based definition of ISO. Their writeup includes this important caveat (ttps://www.dxomark.com/glossary/iso-speed/):

"As tests show, the ISO settings reported by camera manufacturers can differ significantly from measured ISO in RAW. This difference stems from design choices, in particular the choice to keep some “headroom” to avoid saturation in the higher exposures to make it possible to recover from blown highlights."

They start with the ISO 12232 formula

S = 78/Hsat

where Hsat is the exposure at the focal plane which saturates the sensor. They go into some detail to come up with a different formula that uses quantities they can measure in their protocol, but let's go with this one.

For the Olympus at an ISO setting of 800, from their measurements they determine Hsat = 78/380 = 0.2 lux-seconds will saturate the sensor.

For the Nikon at an ISO of 800 they determine an exposure of Hsat = 78/650 = 0.12 lux-seconds will saturate the sensor.

So it looks like Olympus is choosing to provide a little more head-room to recover from blown highlights at any given ISO, which is in line with the caveat quoted above.

This might also explain why Nikon tends to have a lower minimum ISO setting for the same sensor designs.

One thing I've learned with Olympus over the years is that you can squeeze a bit more light using the low ISO setting of 100, especially shooting raw.

See this blog posting from Bill Claff for more on this .. https://www.photonstophotos.net/GeneralTopics/Sensors_&_Raw/Olympus_Sensor_Calibration_as_Compared_with_DxOMark_Measured_ISO.htm  where he concludes Oly is providing an additional 1/2 to full stop additional highlight recovery.

Yes, with the only difference, that I have g9 & A7III to compare.

Hadn't noticed that limitation on DoF for bird shots ( but I am usually limited to 5.6 lenses on FF anyway ) - in general you are trying to grab as much light as possible an sacrificing DoF but most situations in landscape or photos of groups inside, you are needing to control FoV ( ignoring 43 vs 32 aspect ratio differences ) and control the depth of field. This usually means, in my experience, one has to stop down a FF lens to 5,6 or 8 ( for landscapes ).

Precisely. Same for macros. You'd have to stop down FF to f22 or even lower, or at least to f8 and then stack in Helicon. With m43 you can shoot at f2.8 with the added incredible advantage of in-camera focus stacking.

For landscapes, street, architecture and macros, the greater DOF of m43 at wider apertures provides a tangible advantage.

Plenty of cases where the thin DoF is OK or desirable and then FF and bright glass in low light ( with moving subjects ) gets into its own.

Exactly. It makes perfect sense to shoot full frame if you need shallow DOF, like with portraits. Or more pixels, like in landscape or product photography (although m43 has high-res mode). Or consistently shoot in low light, like event / indoor photography.

faunagraphy wrote:

Here's one with the 300mm Pro and 2x TC.

A good image of  a juvenile swallow - which species is it ?

The exif shows  f/9, 1/800 with ISO800

The  lack of motion blur at 1/800 suggests  that the swallow is perched and is stretching its wing rather than flapping or flying and  those exposure settings with ISO800 suggests to me that the light was quite good.

I wouldn’t normally consider f/9 for birding, especially when the light is lower and/or I need to keep shutter speed up as the noise that comes with the necessary high ISO robs the image of feather detail regardless of how sharp the lens light be.

Peter

Regarding DoF with birds

I often read the argument here that . . . “but at the same DoF FF loses the advantage” . . .
But FF doesn’t fall behind. In those situations where one does need that extra depth in the focus FF can easily accommodate. But I for one will readily sacrifice DoF to keep the ISO down and/or the shutter speed up when I need to

And let’s not kid ourselves, if Olympus or Panasonic had made a 300mm f/2.8 m.43 lens users wouldn’t be out in lower light shooting it at f/4 just to maintain a certain DoF.

Peter

Messier Object wrote:

Regarding DoF with birds

I often read the argument here that . . . “but at the same DoF FF loses the advantage” . . .
But FF doesn’t fall behind. In those situations where one does need that extra depth in the focus FF can easily accommodate. But I for one will readily sacrifice DoF to keep the ISO down and/or the shutter speed up when I need to

And let’s not kid ourselves, if Olympus or Panasonic had made a 300mm f/2.8 m.43 lens users wouldn’t be out in lower light shooting it at f/4 just to maintain a certain DoF.

Peter

Won't say that I've never been tempted ...

https://www.houstoncameraexchange.com/used-olympus-43-300mm-f28-ed-prime-lens-excellent-condition-uol4330028e.html?gclid=CjwKCAiAlrSPBhBaEiwAuLSDUI85k-XgvbStQIwkttHy2B7DPXaG9QcqenQJQGZ6l5H0yG_lm0qUQxoCRwYQAvD_BwE

Jeff wrote:

Messier Object wrote:

Regarding DoF with birds

I often read the argument here that . . . “but at the same DoF FF loses the advantage” . . .
But FF doesn’t fall behind. In those situations where one does need that extra depth in the focus FF can easily accommodate. But I for one will readily sacrifice DoF to keep the ISO down and/or the shutter speed up when I need to

And let’s not kid ourselves, if Olympus or Panasonic had made a 300mm f/2.8 m.43 lens users wouldn’t be out in lower light shooting it at f/4 just to maintain a certain DoF.

Peter

Won't say that I've never been tempted ...

https://www.houstoncameraexchange.com/used-olympus-43-300mm-f28-ed-prime-lens-excellent-condition-uol4330028e.html?gclid=CjwKCAiAlrSPBhBaEiwAuLSDUI85k-XgvbStQIwkttHy2B7DPXaG9QcqenQJQGZ6l5H0yG_lm0qUQxoCRwYQAvD_BwE

I’ve had that lens for nearly 10 years. It’s heavy (I’ve broken one 4/3-m43 adapter) and the focus is slow compared with m.43 lenses and my C-AF keeper rate with birds in flight is usually no better than 20% , BUT its overall image rendering is better than anything I’ve seen from any m.43 lens.

I won’t say that I’ve never been tempted by the 300mm F4 Pro or the 150-400mm F4.5 1.25x, but it won’t happen unless my 300/2.8 dies

Peter

Messier Object wrote:

Regarding DoF with birds

I often read the argument here that . . . “but at the same DoF FF loses the advantage” . . .
But FF doesn’t fall behind. In those situations where one does need that extra depth in the focus FF can easily accommodate. But I for one will readily sacrifice DoF to keep the ISO down and/or the shutter speed up when I need to

And let’s not kid ourselves, if Olympus or Panasonic had made a 300mm f/2.8 m.43 lens users wouldn’t be out in lower light shooting it at f/4 just to maintain a certain DoF.

Peter

I would if it weighed 7 lb like the Four Thirds 300mm f2.8.

For what it's worth, I used a Canon 300mm f2.8L for years before upgrading to the 300mm Pro. And it was an upgrade in every respect. The Canon was the sharpest lens I had ever use until I tried the 300mm Pro. I still have the Canon which I use with a focal reducer when I need f2 for wildlife.

I have many reasons but weight is not one of them:

- Incredible detail! It's the only lens that I am happy to use with a 2x teleconverter. The Canon was designed to resolve a full frame sensor and not the pixel-dense m43 sensor

- Sync-IS is unreal. And yes, you can shoot the f2.8 lens at 2x the speed, but I get more keepers with the Pro

Thank you for the comment on the swallow. This is a barn swallow - the fledglings were communing with some tree swallow fledglings and I got many nice photos of them being fed by their parents that day.

faunagraphy wrote:

Messier Object wrote:

Regarding DoF with birds

I often read the argument here that . . . “but at the same DoF FF loses the advantage” . . .
But FF doesn’t fall behind. In those situations where one does need that extra depth in the focus FF can easily accommodate. But I for one will readily sacrifice DoF to keep the ISO down and/or the shutter speed up when I need to

And let’s not kid ourselves, if Olympus or Panasonic had made a 300mm f/2.8 m.43 lens users wouldn’t be out in lower light shooting it at f/4 just to maintain a certain DoF.

Peter

I would if it weighed 7 lb like the Four Thirds 300mm f2.8.

For what it's worth, I used a Canon 300mm f2.8L for years before upgrading to the 300mm Pro. And it was an upgrade in every respect. The Canon was the sharpest lens I had ever use until I tried the 300mm Pro. I still have the Canon which I use with a focal reducer when I need f2 for wildlife.

I have many reasons but weight is not one of them:

- Incredible detail! It's the only lens that I am happy to use with a 2x teleconverter. The Canon was designed to resolve a full frame sensor and not the pixel-dense m43 sensor

I have the Mark II Canon 300mm F/2.8 and it’s the sharpest lens I own. And by the way it was still the top scorer for raw sharpness last time I looked at the DXO lens database. On my E-M1 II and III it is clearly sharper than my 4/3 Zuiko 300mm f/2.8 and remains incredibly sharp even with the Canon 2x so I don’t accept the notion that FF lenses don’t work well with a 20M 4/3 sensor.

Also, I don’t see any comments about the top Canon long Tele lenses not working well with the 32M Canon 90D which has the same pixel density as a 20M 4/3 sensor

- Sync-IS is unreal. And yes, you can shoot the f2.8 lens at 2x the speed, but I get more keepers with the Pro

Thank you for the comment on the swallow. This is a barn swallow - the fledglings were communing with some tree swallow fledglings and I got many nice photos of them being fed by their parents that day.

Jeff wrote:

James Stirling wrote:

Jeep_Joseph wrote:

• Incorrect, it's a 40-150 2.8. However, it's efov to fx is 80-300 5.6.

It is not just effective diagonal AOV it is DOF control/ subject isolation and most critically total light gathered. In other words a FF 80-300mm F/5.6 on a FF camera will do the same job as a 40-150mm F/2.8 om m43. 70{-80}-300mm lenses are widely available and often very inexpensive. The reason being that such a slow lens is pedestrian low end in FF

Nikon AF Zoom-NIKKOR 70-300mm f/4-5.6G Lens 1928 B&H Photo Video (bhphotovideo.com)

While amongst a few of the hard of thinking posters here , denial of equivalence and it's unavoidable consequences is a constant. Alas reality does not support their nonsense , equivalence applies equally to all sensor sizes from the smallest to the largest. Sadly you are not the first or no doubt last to make the same old BS fact dodging claims, it is an embarrassing tradition in the forum

Now to be clear the 40-150mm pros is a great lens for m43 but it is not the same as FF F/2.8 lens. Just as a lens on a smaller sensor format covering the same effective focal range is not the same as the 40-150mm .

is to simply ignore the sensor and concentrate on the lens.

It is rather tricky to take a photo without the lens being attached to a camera . So I would suggest that how the combination performs is all that matters \anything else is irrelevant ,

What determines DOF is distance to the subject, angle of view, and physical lens opening. It's a geometric effect determined by these factors.

What determines light gathering is lens opening, luminance, angle of view, and 1/shutter.

If you need to buy a wide lens opening for good light gathering. A smaller format let's you do that with a shorter lens up to the point it can be made no shorter.

So why not buy the smallest format that meets your needs? No value judgement required, just some understanding what you are getting when you spend your hard-earned money.

Tom Caldwell wrote:

Equivalence physics is distinctly not nonsense and we cannot say a word that disputes it.

Tom, In just about every other forum on DPreview that is the case. However in every single one of the endless M43 comparison to FF threads that plague the forum .Multiple posters will indeed contest physics some times over many dozens of posts going back more than a decade. Sadly this forum works rather like the pathetic shambles that is Westminster, where correcting misreporting is far more likely to get you in trouble than the deed itself

However there is a tendency to put forward that the FF Eq of the M4/3 lens as somehow a negative factor. That 4/3 f2.8 is actually f5.6 equivalent on FF and glory be f5.6 is f11.2 on a FF sensor.

Physics says that this is quite true, and I cannot dispute it, but strangely users of f2.8 seem to get by quite well with their FF equivalent f5.6 lens. Others taking equivalence to heart race off and buy a FF camera body and a f5.6 lens and breathe a sigh of relief.

Users of Mobile Phone Cameras seem quite unfazed about their poor equivalence - in fact many M/3 users are near petrified that Mobile Phone Cameras will rise up and destroy the 4/3 sensor format despite that they are not so good on the equivalence stakes.

This seems a worry on two possible fronts - not equivalent enough for FF and equivalence does not matter for the death march of the Mobile Phone Camera.

It is always harder to be “piggy in the middle” as the 4/3 sensor seems to be. Furthermore does the FF sensor crowd continually genuflect to the Medium Sensor? It seems that only the 4/3 sensor suffers from small-sensor syndrome. And of course we get the factual equivalence theory for breakfast, dinner and supper….

I would argue that if M4/3 does what we need it to do for us that is all that matters.

Accidental test images:

https://www.dpreview.com/forums/post/65636493

Being able to shoot at 1/200th at F/4 and only 400 ISO is far from challenging lighting . In a more demanding scenario the the better ISO performance and light gathering abilities of the FF camera and lens would have shown themselves to do a better job. DOF is clearly not an issue as your Canon shot is at F/2 with the same DOF as a m43 lens at F/1

I did not set out to make this comparison but realised later that it might be interesting. Three combinations here, two are M4/3 and one is a 51Mp FF sensor on an exotic Canon EF 200/2.0 lens. Compare the EXIF and no doubt there is equivalence involved, perhaps rather less that might be expected? Same show, same cast, same lighting. I have many more that prove that the images were not flukes.

End of story - despite equivalence it is possible get good enough images for purpose with M4/3 gear. The images as displayed on dpreview seem darker than what the originals were on my computer screen.

No one has ever said that you cannot get great results with m43 . That is typically a strawman thrown in when posters don't like the facts of equivalence being mentioned

Here are ten more images all taken with M4/3 gear from the same show. Includes the Olympus 40-150/2.8 and Panasonic 200/2.8 + 1.4x TC. Again the slower FF Eq f-stop does not seem to have been a huge negative to be overcome.

https://www.dpreview.com/forums/post/65634034

faunagraphy wrote:

SonyX wrote:

Bored_Gerbil wrote:

Jeep_Joseph wrote:

• Incorrect, it's a 40-150 2.8. However, it's efov to fx is 80-300 5.6.

No. It’s equivalent field-of-view is 80-300mm on FF and its equivalent depth-of-field is the same as f5.6 on FF, but it is an f2.8 Lens.

Please don’t bog EVERYTHING down in “equivalence”.

Cheers The Gerbil

So, what are the benefits do you see for m43 f/2.8 lens over f/5.6 on FF?

4x more light gathering. Although how much of that collected light is actually used also depends on the sensor.

You do understand that aperture is a ratio and as such your claim is nonsense

But yes, an f2.8 lens on a m43 camera will focus in poor light easily, whereas the FF camera with the f5.6 lens won't be able to "see" the subject at all (or see it but not focus).

That is not correct the way mirrorless cameras focus allows for much slower apertures to provide full AF. From an AF perspective m43 is hardly setting the heather on fire. Only the hefty by m43 standards E-M1X makes it into the top 12 from a well respected site. There are FF mirrorless cameras from Nikon, Canon, Leica, Panasonic and of course Sony

Homepage - Mirrorless Comparison

With m43, you get 2x reach and more DOF without cutting down on light. More DOF is an advantage for subjects like macros and some wildlife shots.

There is no DOF advantage or reach if you want to get the same diagonal AOV, same DOF control/subject isolation and same total light gathering. Worst case scenario if you cannot use a slower shutter speed or shallower DOF and need to increase the ISO on the FF using a 300mm @ f/5.6 will give you the same diagonal AOV same DOF and same noise { ignoring the processing possibilities afforded by the much higher MP FF models }

Bassaidai wrote:

This lens replaces my trusty Canon EF 70-200/2.8 AND Sigma 120-300/2.8, at roughly a fifth of the size, weight and price.

There are no free lunches , you have to sacrifice 2 full stops of light gathering to shoot the 40-150mm on m43. Or alternately you could have simply picked up a 70-300mm for Canon they have a number of them ranging from very cheap to L level. The L model is approx 50% heavier however it starts at F/4 so you would need a 40-150mm F/2-2.8  to do the same job . The Canon L 70-300mm is also a little shorter

Messier Object wrote:

faunagraphy wrote:

Messier Object wrote:

Regarding DoF with birds

I often read the argument here that . . . “but at the same DoF FF loses the advantage” . . .
But FF doesn’t fall behind. In those situations where one does need that extra depth in the focus FF can easily accommodate. But I for one will readily sacrifice DoF to keep the ISO down and/or the shutter speed up when I need to

And let’s not kid ourselves, if Olympus or Panasonic had made a 300mm f/2.8 m.43 lens users wouldn’t be out in lower light shooting it at f/4 just to maintain a certain DoF.

Peter

I would if it weighed 7 lb like the Four Thirds 300mm f2.8.

For what it's worth, I used a Canon 300mm f2.8L for years before upgrading to the 300mm Pro. And it was an upgrade in every respect. The Canon was the sharpest lens I had ever use until I tried the 300mm Pro. I still have the Canon which I use with a focal reducer when I need f2 for wildlife.

I have many reasons but weight is not one of them:

- Incredible detail! It's the only lens that I am happy to use with a 2x teleconverter. The Canon was designed to resolve a full frame sensor and not the pixel-dense m43 sensor

I have the Mark II Canon 300mm F/2.8 and it’s the sharpest lens I own. And by the way it was still the top scorer for raw sharpness last time I looked at the DXO lens database. On my E-M1 II and III it is clearly sharper than my 4/3 Zuiko 300mm f/2.8 and remains incredibly sharp even with the Canon 2x so I don’t accept the notion that FF lenses don’t work well with a 20M 4/3 sensor.

Also, I don’t see any comments about the top Canon long Tele lenses not working well with the 32M Canon 90D which has the same pixel density as a 20M 4/3 sensor

The Canon is indeed very sharp - it's just that my Pro is slightly better. The difference becomes more apparent when the Pro is paired with my MC-20. The Canon - or at least MY Canon - doesn't give good photos with the 2x TC. The biggest limitation is Olympus AF which doesn't allow for consistently accurate AF and so handicaps the lens.

Perhaps my copy of the Olympus Pro is just that good, although I had no complaints when the Canon was my primary lens. I used to pair it with my 50-200 SWD and was / am very happy with the results.

Before purchasing the Pro, I viewed many sample photos taken with the Zuiko 300mm and I didn't find it to be as good as the Canon either, plus it's 2 lb heavier.

- Sync-IS is unreal. And yes, you can shoot the f2.8 lens at 2x the speed, but I get more keepers with the Pro

Thank you for the comment on the swallow. This is a barn swallow - the fledglings were communing with some tree swallow fledglings and I got many nice photos of them being fed by their parents that day.

James Stirling wrote:

faunagraphy wrote:

SonyX wrote:

Bored_Gerbil wrote:

Jeep_Joseph wrote:

• Incorrect, it's a 40-150 2.8. However, it's efov to fx is 80-300 5.6.

No. It’s equivalent field-of-view is 80-300mm on FF and its equivalent depth-of-field is the same as f5.6 on FF, but it is an f2.8 Lens.

Please don’t bog EVERYTHING down in “equivalence”.

Cheers The Gerbil

So, what are the benefits do you see for m43 f/2.8 lens over f/5.6 on FF?

4x more light gathering. Although how much of that collected light is actually used also depends on the sensor.

You do understand that aperture is a ratio and as such your claim is nonsense

You are clearly confusing the light that comes into a lens with the light that is projected on the sensor. Yes, these quantities are (almost) the same, but the light from a FF lens is projected on to a 4x bigger area.

So although both a FF f5.6 lens and a m43 f2.8 lens have nearly the same-sized front element, the "density" of light projected by the m43 lens is 4x more. Hence it is indeed an f2.8 lens. The next variable is what the sensor does with this light which per unit area contains 4x more "information" for the m43 lens.

But yes, an f2.8 lens on a m43 camera will focus in poor light easily, whereas the FF camera with the f5.6 lens won't be able to "see" the subject at all (or see it but not focus).

That is not correct the way mirrorless cameras focus allows for much slower apertures to provide full AF. From an AF perspective m43 is hardly setting the heather on fire. Only the hefty by m43 standards E-M1X makes it into the top 12 from a well respected site. There are FF mirrorless cameras from Nikon, Canon, Leica, Panasonic and of course Sony

Homepage - Mirrorless Comparison

More confusion - perhaps deliberate goalpost shifting. Those figures represent the capability of AF tracking algorithms / processing power and not AF sensitivity or AF acquisition speed.

faunagraphy wrote:

James Stirling wrote:

faunagraphy wrote:

SonyX wrote:

Bored_Gerbil wrote:

Jeep_Joseph wrote:

• Incorrect, it's a 40-150 2.8. However, it's efov to fx is 80-300 5.6.

No. It’s equivalent field-of-view is 80-300mm on FF and its equivalent depth-of-field is the same as f5.6 on FF, but it is an f2.8 Lens.

Please don’t bog EVERYTHING down in “equivalence”.

Cheers The Gerbil

So, what are the benefits do you see for m43 f/2.8 lens over f/5.6 on FF?

4x more light gathering. Although how much of that collected light is actually used also depends on the sensor.

You do understand that aperture is a ratio and as such your claim is nonsense

You are clearly confusing the light that comes into a lens with the light that is projected on the sensor. Yes, these quantities are (almost) the same, but the light from a FF lens is projected on to a 4x bigger area.

So although both a FF f5.6 lens and a m43 f2.8 lens have nearly the same-sized front element, the "density" of light projected by the m43 lens is 4x more. Hence it is indeed an f2.8 lens. The next variable is what the sensor does with this light which per unit area contains 4x more "information" for the m43 lens.

It looks like you again invented the wheel. 4 times more light comes to 4 times smaller sensor. You get equal amount of of light with m43 f/2.8 as f/5.6 on FF

But yes, an f2.8 lens on a m43 camera will focus in poor light easily, whereas the FF camera with the f5.6 lens won't be able to "see" the subject at all (or see it but not focus).

That is not correct the way mirrorless cameras focus allows for much slower apertures to provide full AF. From an AF perspective m43 is hardly setting the heather on fire. Only the hefty by m43 standards E-M1X makes it into the top 12 from a well respected site. There are FF mirrorless cameras from Nikon, Canon, Leica, Panasonic and of course Sony

Homepage - Mirrorless Comparison

More confusion - perhaps deliberate goalpost shifting. Those figures represent the capability of AF tracking algorithms / processing power and not AF sensitivity or AF acquisition speed.

Skeeterbytes wrote:

Foundational lens in the m4/3 system and one I can't imagine being without. So useful, so very good. Love that it is sharper as it is zoomed longer, which seems very unusual for zoom lenses in general. Dual focus motors, constant aperture, internal zoom--ideal.

Lenstip resolution graph

It was just Oly's second Pro series lens and has been out nearly eight years now. Should they ever refresh, OIS and a focus limit switch would be welcome additions. I'm weird in liking the complicated lens hood.

Cheers,

Rick

Unless you're shooting with a Panasonic camera fitted, I am surprised at your request for lens OIS and focus limit.

I shoot this lens with an em1-mk2 and stabilisation is superb, also at a touch of my right forefinger I have 3 pre programmed focus limits - without having to resort to repositioning either of my hands.

Perfect

SonyX wrote:

faunagraphy wrote:

James Stirling wrote:

faunagraphy wrote:

SonyX wrote:

Bored_Gerbil wrote:

Jeep_Joseph wrote:

• Incorrect, it's a 40-150 2.8. However, it's efov to fx is 80-300 5.6.

No. It’s equivalent field-of-view is 80-300mm on FF and its equivalent depth-of-field is the same as f5.6 on FF, but it is an f2.8 Lens.

Please don’t bog EVERYTHING down in “equivalence”.

Cheers The Gerbil

So, what are the benefits do you see for m43 f/2.8 lens over f/5.6 on FF?

4x more light gathering. Although how much of that collected light is actually used also depends on the sensor.

You do understand that aperture is a ratio and as such your claim is nonsense

You are clearly confusing the light that comes into a lens with the light that is projected on the sensor. Yes, these quantities are (almost) the same, but the light from a FF lens is projected on to a 4x bigger area.

So although both a FF f5.6 lens and a m43 f2.8 lens have nearly the same-sized front element, the "density" of light projected by the m43 lens is 4x more. Hence it is indeed an f2.8 lens. The next variable is what the sensor does with this light which per unit area contains 4x more "information" for the m43 lens.

It looks like you again invented the wheel. 4 times more light comes to 4 times smaller sensor. You get equal amount of of light with m43 f/2.8 as f/5.6 on FF

And therefore the FF sensor has 1/4th the light per unit area as a m43 sensor. So you have a 150mm f2.8 lens with the angle of view of a 300mm FF lens. However for the FF sensor to receive the same amount of information per unit area from this 300mm lens, it will also have to be an f2.8 lens, not f5.6.

An f2.8 FF lens will collect 4x the light as a m43 lens, but the DISTRIBUTION of this collected light over the sensor will be exactly like that of the f2.8 m43 lens because it has to project over a 4x sensor area.

The part that you and James keep getting confused over is thinking that the information that a FF sensor gets from a f5.6 lens is the same as what a m43 sensor receives from a f2.8 lens. What the lens collects is not what the sensor receives because sensor sizes are different.

That said, one reason why FF sensors have better high ISO performance is because there are no 80MP FF sensors. The difference is NOT 2 stops, as explained above.

faunagraphy wrote:

SonyX wrote:

faunagraphy wrote:

James Stirling wrote:

faunagraphy wrote:

SonyX wrote:

Bored_Gerbil wrote:

Jeep_Joseph wrote:

• Incorrect, it's a 40-150 2.8. However, it's efov to fx is 80-300 5.6.

No. It’s equivalent field-of-view is 80-300mm on FF and its equivalent depth-of-field is the same as f5.6 on FF, but it is an f2.8 Lens.

Please don’t bog EVERYTHING down in “equivalence”.

Cheers The Gerbil

So, what are the benefits do you see for m43 f/2.8 lens over f/5.6 on FF?

4x more light gathering. Although how much of that collected light is actually used also depends on the sensor.

You do understand that aperture is a ratio and as such your claim is nonsense

You are clearly confusing the light that comes into a lens with the light that is projected on the sensor. Yes, these quantities are (almost) the same, but the light from a FF lens is projected on to a 4x bigger area.

So although both a FF f5.6 lens and a m43 f2.8 lens have nearly the same-sized front element, the "density" of light projected by the m43 lens is 4x more. Hence it is indeed an f2.8 lens. The next variable is what the sensor does with this light which per unit area contains 4x more "information" for the m43 lens.

It looks like you again invented the wheel. 4 times more light comes to 4 times smaller sensor. You get equal amount of of light with m43 f/2.8 as f/5.6 on FF

And therefore the FF sensor has 1/4th the light per unit area as a m43 sensor. So you have a 150mm f2.8 lens with the angle of view of a 300mm FF lens. However for the FF sensor to receive the same amount of information per unit area from this 300mm lens, it will also have to be an f2.8 lens, not f5.6.

An f2.8 FF lens will collect 4x the light as a m43 lens, but the DISTRIBUTION of this collected light over the sensor will be exactly like that of the f2.8 m43 lens because it has to project over a 4x sensor area.

The part that you and James keep getting confused over is thinking that the information that a FF sensor gets from a f5.6 lens is the same as what a m43 sensor receives from a f2.8 lens. What the lens collects is not what the sensor receives because sensor sizes are different.

That said, one reason why FF sensors have better high ISO performance is because there are no 80MP FF sensors. The difference is NOT 2 stops, as explained above.

The units are - the pixels, and they are 4 times bigger on FF. And this is the main  reason of better high ISO performance. Another reason is BSI and dual gain.

You can't compare 80mp with 20mp here, it is completely different subject and possibilities.

And yes, noise difference is roughly 2x, when you compare properly exposed images.

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Wildlife photography in central and western India, and the Pacific Northwest. Mostly Micro Four Thirds with some Nikon F.