Why Four Thirds is better - Lets continue here

[Joseph S Wisniewski]

Surely one would
need differently offset microlens for each lens?

I never jest, and don't call me Shirley.

Seriously, no, you wouldn't. Theoretical simulations (analyzing the heck out of Sony, Kodak, and Foveon data sheets), actual measurements of the capabilities of the sensors in at least a dozen different DSLRs, and real world experience shooting with at least a dozen different DSLRs and about 100 different lenses all bear out the same observation: there's not really a problem with sensor angle of incidence until you pass about 15 degrees (and some sensors are good to around 20 degrees).

So, you can offset the microlenses inward at progressively larger angles until you reach about 10 degrees in the corners, and then even the longest telephotos won't have a problem (they've got 10 degrees inward that they don't need, but it takes 15 degrees to disrupt the image), and it takes a wide angle that's 25 degrees off axis (15 degrees originally + 10 degrees of offset). The closest exit pupil I've ever measured on a film SLR lens was 52mm from the film plane, which is an angle of arctan(43.3mm/2/52mm) = 22.6 degrees from perpendicular. So, a 10 degree offset reduces that 22.6 degrees to 12.6, and that will work wonderfully.

A 10 degree offset is a "universal cure all", even for film SLR lenses on a full frame sensor.

For a smaller 1.33x crop sensor, you can even have a pretty much universal microlens setup that will work on rangefinder lenses.

Wide angle size isn't the issue, it is big teles that break your back.

There are all sorts of photographers. Some want to take the camera out on the street. Some do landscapes. Some do portraits.

The issue of "big teles that break your back" isn't a question of sensor size, but of pixel pitch. Oly launched E-1 with a 5mp sensor at a 2x crop. Before they launched any other E system cameras, Nikon launched D2X, 12.2mp at the 1.5x "Nikon DX" crop, but also with a "high speed crop mode" that switched it to 6.8mp on a 2x crop. So, the Nikon shooters had the advantage of an even finer pixel pitch than the Oly shooters, and a 300mm f2.8 that was lower cost than Oly's, lighter, sharper (based on what I've seen to date), more sophisticated (vibration reduction).

As I understand it, chip sizes are coming down (not sensors, juts
microchips in general). This will make larger chips ever more
specialised and expensive.

Nope. The sensor manufacturers are producing chips in large enough quantities to run lines full time. Canon (with in house production at two million APS sized sensors a year) needs to run 30,000 wafers a year. Even running 24/7, that's 3.4 wafers an hour. They need at least two full lines in a decent fab to keep up with that. If you've got that kind of chip production, you put serious effort into getting costs down.

The main gripe about FT is noise. Doesn't bother me, but it is a
genuine problem for some and some kind of totem to all sorts of
people who know no better.

"Know no better"? Today I shot over 700 pics mostly wide open with an f2.8 telephoto, at ISO 400 and was still running shutter speeds a bit too low for my subject.

However, soon enough pixel counts will hit the resolution of
affordable optics. Soon after that, noise will fall, on all
systems, to negligable.

There's nothing in current sensor trends to support your claims about noise. And nothing in physics to support it, either.

After THAT, FT may start to look too large a sensor size.

Hardly. I think it's too small for a decent SLR. To get a bright enough viewfinder, you have to make the focusing screen so transparent that it's hard to focus. Did you catch the discussion between OzRay and I about his fast lens focusing problems?

It may be a good sensor size for electronic viewfinder cameras, if you're willing to put up with the other limitations.

--
Normally, a signature this small can't open its own jumpgate.

Ciao! Joe

http://www.swissarmyfork.com

 

[Joseph S Wisniewski]

I think a more interesting discussion is what will be the impact of
the offset microlens sensor on the future of digital photography.

None.

Hmmm...

How about full frame DSLRs that work with all existing film SLR lenses exactly as well as those lenses worked with film?

How about a system where the DLSR has a 110 film sized sensor (yup, that's the size of the four thirds (tm) sensor), but the DSLR and lenses are the size of those for the old Pentax 110 film SLR, instead of the size of four thirds (tm) lenses?

It seems that you are expecting too much from the offset
microlenses; it is obvious this "solution" will be
counterproductive with telephoto lenses,

It's only "obvious" if you make assumptions without doing any math. As I mentioned in my reply to Louis Dobson elsewhere in this thread, microlenses are benign to telephoto lenses, they do no harm. They are not "counterproductive".

http://forums.dpreview.com/forums/read.asp?forum=1018&message=20063696

The Leica Modul-R has a mild offset to its microlenses, but it's popular with birders, who have reported no ill effects with Leica 600mm telephotos. You haven't seen people fussy about image quality until you've spent some time with Leica shooting birders.

which is probably the
reason it is only used in the M8, which has no (real) telephoto
lenses. For optimal results the microlenses should have a different
offset for each lens, and even in the optimal situation it isn't a
100% solution. Well, soon we'll have tests on-line that will make
this painfully visible.

Well, they will make something painfully visible. But I believe that it shall be the errors in your assumptions.

--
Normally, a signature this small can't open its own jumpgate.

Ciao! Joe

http://www.swissarmyfork.com

 

[Agramer]

I'm waiting for new pro build 4/3 camera with 5fps, cca 10mpix and
some kind of IS/VR/AS... If it shows untill next summer i'll buy it
+ 11-22/2,8-3,5 and 35-100/2,0. If it doesn't show next yaear . .
.? I'll see next year

Well hopefully you'll get what you want from Olympus, because you
seem to enjoy your lenses ... and good glass ( by whatever measure
is important to you ) is a joy to use.

I like zooms because they are friendly they walk instead of me
I want a good prime just for a portraits. . .and I need them for macros too.
Enjoy your gear
Cheers

 

[Jay Turberville]

I got even better results with assorted Nikkors, old and new. Jay,
you're preaching to the choir on this one.

Well, the 50mm f/1.4 Takumar is great - very even illumination at f/2.0. I haven't checked the 50-300mm f/4.5 ED Nikkor. But my guess is that its exit pupil is way out there. I brought up the Hexanon because it appears to be pretty symmetrical which makes the point that Olympus really has a fair bit or room to play with. There is no technical reason that Olympus can't release some lenses with exit pupils closer to the sensor. They could even classify them as a special "compact ZD" series and make the point that some things have been sacrificed for the extra compact design. Certainly, we don't complain about the vignetting of the 14-45mm kit lens since we understand that they probably sacrificed a bit to keep the cost down. Nothing unreasonable about that. But if kit lenses can be sacrificed on the alter of compromise, then why not some compacts?!? (The question is not directed at you, Joe. It is an open question to Olympus.)

I assume that Olympus does better with their more expensive non-kit
lenses.

It does. But then again, the original 14-54mm (hate that, you look
at 14-45 and 14-54 and thing one of the two is a typo) that I had
on the bench had a 30mm image circle at its widest setting, so I'd
not expect much vignetting in the 22mm "four thirds" part of that.

I don't think this is an image circle issue, though I could be wrong. It is the exit pupil being cut-off by the size of the rearmost lens element.

I quite agree. I know which of my lenses vignette, and compose
around it. Then again, I started photography as a teenager, with a
budget that meant learning how to work around the quirks of lenses
that were, well, "interesting". I'm betting you were the same.

Probably similar. I could afford one of two cameras. A Minolta SRT-100 or a Pentax K1000. My first two lenses were K-mart Focals. I still have the 28mm. I lost track of the 80-200mm somehow. Neither were very good, but were acceptable if you stopped down.

As I've said many times, 50mm exit pupils shouldn't be a problem.
That's only 12.4 degrees from perpendicular in the corners. 9.9 deg
horizontal, a 2.3% drop in sensitivity on the KAF-5101 in the E-1.
7.4 deg vertical. a 2.1% drop. Combined, that's 0.06 stops of
vignetting, beyond what you'd already expect from Cos4 vignetting.
(This is based on using Engauge to digitize the graphs in the .pdf
data sheets). The sensor in E-300 is even better.

I think the E-500 uses the same sensor. Just a different hot mirror. And my test seems to agree with your calculation.

Since I'm not familiar with any film SLR lens (including Oly OM
lenses) with an exit pupil closer than 50mm to the film plane, I
really wonder why Oly had to make such a fuss about needing new
lenses.

I dunno. Even though I have Olympus cameras, it's my opinion that the 1.5x or 1.6x crop is the best overall compromise sensor size. I think Olympus let the engineers have too much control. That said, I really do like the E-300 and E-500. They work fine for me.

--
Jay Turberville
http://www.jayandwanda.com

 

[Jay Turberville]

Hardly. I think it's too small for a decent SLR. To get a bright
enough viewfinder, you have to make the focusing screen so
transparent that it's hard to focus. Did you catch the discussion
between OzRay and I about his fast lens focusing problems?

I dunno. The difference is half a stop. And from what I can gather, just about any AF DSLR has the same problem with the microlens arrays on the focus screens. It goes back to before DSLRs and to AF 35mm cameras.

--
Jay Turberville
http://www.jayandwanda.com

 

[LJSmak]

It's only "obvious" if you make assumptions without doing any math.
As I mentioned in my reply to Louis Dobson elsewhere in this
thread, microlenses are benign to telephoto lenses, they do no
harm. They are not "counterproductive".

Well they would be, if the diagrams about how they work are correct.

Well, they will make something painfully visible. But I believe
that it shall be the errors in your assumptions.

We'll see; I have no doubt the M8 is a great quality camera (with a 28mm asph lens on it) but it doesn't suit my style at all. For what I do the most, it is close to useless. I like the R9 though.

Lourens

 

[Louis_Dobson]

Joseph S. Wisniewski wrote:
[Microlens discussion]

Interetsing, and I'd just take your word for it if it wasn't for the tone of the rest

Wide angle size isn't the issue, it is big teles that break your back.

There are all sorts of photographers. Some want to take the camera
out on the street. Some do landscapes. Some do portraits.

Quite. Which is why there will be a market for MF, 35mmFF and FT cameras.

The issue of "big teles that break your back" isn't a question of
sensor size, but of pixel pitch.

Quite. Oly are running the highets pixel pitch these days, giving the most image form the smallerst FF lens.

[high speed Nikon setting]

A kludged high speed setting on a big sensor is not the same as a small sensor.

[chip sizes and costs]

Not really the point. Everything about physically big chips will become more expensive as it becomes odder technology.

The main gripe about FT is noise. Doesn't bother me, but it is a
genuine problem for some and some kind of totem to all sorts of
people who know no better.

"Know no better"? Today I shot over 700 pics mostly wide open with
an f2.8 telephoto, at ISO 400 and was still running shutter speeds
a bit too low for my subject.

See above. Sounds like you need a big sensor camera. I've gone above ISO 100 twice this year, IIRC. Noise is not an issue for me. If I shot a bird, I'd give it to my cook.

On the other hand, I've just packed up to walk five miles in high temparatures across soft sand. Size and weight IS an issue to me.

However, soon enough pixel counts will hit the resolution of
affordable optics. Soon after that, noise will fall, on all
systems, to negligable.

There's nothing in current sensor trends to support your claims
about noise. And nothing in physics to support it, either.

Chip performance improves all the time. NMOS should, eventually, make for very high resolution with very low noise.

After THAT, FT may start to look too large a sensor size.

Hardly. I think it's too small for a decent SLR. To get a bright
enough viewfinder, you have to make the focusing screen so
transparent that it's hard to focus. Did you catch the discussion
between OzRay and I about his fast lens focusing problems?

I find dSLRs viewfinders unusbale for focus anyway - no focusing aids, for some daft reason. There is nothing whatever wrong with the E1 viewfinder, and I prefer to use an E500, which is a lousy viewfinder thanks to the nasty cost-cutting idea of gluing a couple of mirrors inside the case instead of providing a pentaprism. I find it makes no difference whatevere, in use. I also sometimes shoot with the 5D - "nice viewfinder" I say to myself as I lift it for the first time to my eye, and that's the last time I notice. Not an issue, frankly.

It may be a good sensor size for electronic viewfinder cameras, if
you're willing to put up with the other limitations.

I suspect in ten years ALL cameras will be EVF.

--
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[marf]

An offset microlens sensor negates the arguments about needing new
"near telecentric" lenses for digital photography.

telecentricity is talked about but is not an element of the FT standard: see
http://www.four-thirds.org/en/about/standard.html

 

[Joseph S Wisniewski]

An offset microlens sensor negates the arguments about needing new
"near telecentric" lenses for digital photography.

telecentricity is talked about but is not an element of the FT
standard: see
http://www.four-thirds.org/en/about/standard.html

No one knows what actually is part of the four thirds (tm) "standard", outside of a small, select group of people ho has seen it. The best way to see what is or is not "an element" of four thirds is to look at the four thirds patent. Since Oly apparently wants to control four thirds tightly (or they wouldn't have taken out patents, trademarks, and copyrights, and they wouldn't be so selective with ho is allowed access to the specification) they have to enforce the patent. It spells out telecentricity quite clearly, including the angles.

By the way, if you're a fan of four thirds, you should never refer to it as "FT" or "4/3". "Four thirds" is a registered trademark of Olympus, by using other terms, you'll hurt Olympus. They'll either have to waste effort employing "watchdogs" to correct public misuse of their trademark, or risk having it declared unenforced in court.

--
Normally, a signature this small can't open its own jumpgate.

Ciao! Joe

http://www.swissarmyfork.com

 

[marf]

http://www.four-thirds.org/en/about/standard.html

No one knows what actually is part of the four thirds (tm)
"standard", outside of a small, select group of people ho has seen
it.

Ok, FT is not an "open" standard, the word "open" is only there for marketing.

In reality FT is a system created by olympus, reviewed by kodak, and shared with sigma, fuji, panasonic, sanyo and leica, and new members are not wanted.
But thats the only negative point of the FT standard.
I can live with it.
You bring that in every post you write.

 

[E1derful]

So, if this
spreads, and larger sensor cameras can actually have wide angle
lenses that are more compact than those of equivalent coverage on
the four thirds system, and the price on larger sensors continues
to drop, is there really a reason for the four thirds system to
continue?

As your model continues flourish, what will happen to APS sized systems? I suppose their purpose for existance will be negated as well. You will have to switch to Canon and give up your Nikon because its purpose for existance will be negated...unless they make FF as well.

All current camera systems will one day be completely obsolete. Even the Canon EF system...so your argument regarding purpose for existance and "reason to continue" are complete hogwash and they even have a snide edge to them. If your statement had be spouted in an Olympus forum, one may even take it as a form of trolling...luckily...you did it in an Open Forum where the troll rules seem to be a bit more lax....

I will attempt to answer your "I am better than you" phrased question...but let me repost it so that you konw exactly the excerpt that I am going to work from.

is there really a reason for the four thirds system to continue?

YES!!! There are plenty of reasons to continue. Where there is money to be made...there is cause to continue. Where there is technology present to ofer the consumer a quality product that delivers as promised...there is cause to continue. When a company known for their optical quality and innovation creates the world's first F2 zoom lenses...there is cause to continue. When a digital system created from scratch is developed wiothout any lingering legacy infuences...there is cause to continue...when a company's dust removal initiative finally forces other companies to develop similar technology...there is cause to continue...

If there were no companies like Olympus who constantly push the technology envelope...then large compaines like Canon with overwhelming market share will do little to nothing to improve on their products.

What the photographic communits does not realize is that they need Olympus....they don't need 4/3...but they do need Olympus. Olympus is very innovative and their existance in this market forces others to stay somewhat innovative. What I like most about 4/3 is that they started fresh. I don't feel that there is enough of an advantage to APS for Olympus to have chosen a larger sensor. If Oly were to scrap 4/3 and start fresh again...going to APS would be a complete waste of time...they would need to get larger...

Could you imagine a telecentric design based on APS or FF?

So at this point, you are proposing that Olympus apologze to the photographic community and pack things up and put the DSLR business to rest? That is what I perceived from your quote above. If this is your "suggestion" than you are not nearly as smart as I previously thought you were.

 

[Jay Turberville]

By the way, if you're a fan of four thirds, you should never refer
to it as "FT" or "4/3". "Four thirds" is a registered trademark of
Olympus, by using other terms, you'll hurt Olympus. They'll either
have to waste effort employing "watchdogs" to correct public misuse
of their trademark, or risk having it declared unenforced in court.

Olympus quite consistently fails to include the (TM) when they use "Four Thirds." They don't seem to be going to much effort to protect the trademark.

Also, I don't see how other people using a shorthand version of a trademarked name weakens the trademark. Trademarks usually get weakened when the actual trademark falls into common usage in reference to common generic products. This happened to "aspirin", ("heroin" too I think - yes, a former Bayer trademark), "yo-yo" and a few others. So if some other company comes out with a camera system that uses a 4/3" sensor and your offset microlens idea for instance, there will be a greater danger of confusion. And then they will need to be vigilant in trying to keep people from referring to this new system as "Four Thirds". If they wanted to hedge against such things, they might want to try to trademark thinks like "4/3s" or "4/3 system" if possible.

But if you are really concerned for Olympus, you might want to update your own web pages to remove your references to "4/3" to reflect this new-found concern for Olympus' trademark.

--
Jay Turberville
http://www.jayandwanda.com

 

[EMale]

You need to compare 300mm to 300mm, 600mm to 600mm. The crop of
the sensor does not change the lens. So when comparing size, you
have to look at matching lenses. So you can't do 300mm verses
600mm

You don't compare 'theoretical things' when out in the field, do you? No, you'd slap two prints down on the table and compare.

The 300mm oly comes with.. I repeat.. comes with an included 2x multiplier to get you to 35mm equivalence.

If we didn't want that 35mm equiv, we'd say it was a 300mm lens!

So it's right to compare the 600mm image from the oly 300/2.8 with a 600mm lens on a canon full frame.

That's just the way it is...

p.s Can I also say about Oly's claimed 'size advantage'.. it is only for the lng teles... the normals zooms to wides are 35mm-like in size and they don't have any size advantage.. but the long teles do! That's what Oly meant and they illustrated it with artwork of a 300mm 4/3rds lens and a 600mm 35mm lens.

 

[Jay Turberville]

So it's right to compare the 600mm image from the oly 300/2.8 with
a 600mm lens on a canon full frame.

Right. The Oly 300/2.8 compares to a 600/5.6 on a 36x24mm sensor.

That's just the way it is...

Yup.

p.s Can I also say about Oly's claimed 'size advantage'.. it is
only for the lng teles... the normals zooms to wides are 35mm-like
in size and they don't have any size advantage.. but the long teles
do! That's what Oly meant and they illustrated it with artwork of a
300mm 4/3rds lens and a 600mm 35mm lens.

Except I'm guessing they conveniently forgot to equate apertures while they were at it. When you do that, suddenly the size advantage disappears.

--
Jay Turberville
http://www.jayandwanda.com

 

[EMale]

That's just the way it is...

Yup.

Yeah, you put the print from the 600mm FOV oly next to the print from the 600mm FOV canon. The rest is just semantics.

That's what Oly meant and they illustrated it with artwork of a
300mm 4/3rds lens and a 600mm 35mm lens.

Except I'm guessing they conveniently forgot to equate apertures
while they were at it. When you do that, suddenly the size
advantage disappears.

No, they didn't draw the apertures! Just the respective lenses with their respective FOVs!

It's hard work this 'setting the record straight', lark, isn't it?

 

[TrapperJohn]

I don't like my 4/3 gear because it's 4/3, I like it because Olympus makes it. They turn out a Quality product.

My E1 did't come with a crummy kit lens that has one reaching for the B&H catalog after the first few shots. It came with a fast 14-54 that's crystal clear across it's entire range. No disappointments there.

It doesn't get dust on the sensor. It doesn't drop dead at the first hint of moisture. The body is built with a quality feel that makes a 5D feel like a toy. It's rock solid and fits the hand perfectly. Everything is right where it should be - DOF preview button, WB button, two thumbwheels for full manual control without going through a maze of menus, a B/W LCD screen on top that you can actually read in bright sunlight, to review and change settings. You may not be able to talk about this camera online, but you can sure use it in the field. Reminds me of my old Nikon F3, a no excuses photographic tool.

And the glass... just superb. The 50-200 is razor sharp, and doubles as a decent macro lens with an extension tube. 50 Macro is a darn good portrait lens, really kills DOF if you want to. 11-22 is turning out to be a terrific carry around lens, no bad focal lengths in that beauty, either. The 7-14 is without peer. Not cheap, but Canon makes nothing like that, nor does Nikon.

Nor did Olympus pull the legacy lens con job on me. They did release the 4/3 to OM adapter, albeit reluctantly. But they aren't out saying that they have 200 lenses for their system (with a tiny asterisk at the end of that statement). And they were right - I have used my old Nikkor primes on my E1, but found that my best Nikkor ED 200 3.5 could resolve no better than my 50-200 at 200. I do have to say that my Nikkor 105 1.8 does produce terrific results on the E1.

Actually, I confess that I have improved my photography vastly in the last year. Not by getting online and yammering about specs and marketing strategy and spending a lot of money changing from one brand to another, but by focusing on technique - lighting, composition, and just learning to look at a subject from a variety of angles. And it didn't cost me one red cent to do that.

 

[EMale]

F/2.0 on 4/3 system is not brigher than 2.8 on full frame 135mm.

Hmmm... Then why is one f2 and the other f2.8?

Nah.. nice try but I think you're wrong! F2 is F2 is F2 whatever the format! Unless someone wants to educate me on why he's right?

What Olympus did with their lens in
comparison to the sensor size is indeed larger because the image
area is 1/4 of the full frame lens,

Which lets in more light for the size of the format! f2 is brighter than f2.8!

 

[EMale]

Smaller than what?

An f2.0 on a system that didn't need to be quite as telecentric
than Olympus.

So if canon or nikon make that constant f2 zoom smaller than the zuiko, they've compromised or taken a shortcut that Oly didn't do! Make sense?

Olympus don't make lenses bigger than they have to be.. in fact, I'd bet they try to get them as small as possible.

But I'd acknowldge that if in a perfect design for 1 of a 'tier' of lenses, the entry pupil came in at 65mm when the rest of the tier was 67mm, they'd enlarge that lens by 2mm so as to keep commonality in filter thread sizes.

But you won't convince me that a 35mm/DX/APS size f2 zoom will have the same 'corner to corner' image quality and non-vignetting as an Oly F2 zoom if it has been made smaller.

You're welcome to try tho! I appreciate anyone who educates and doesn't just baffle me with a one-liner.

Pixel mapping...any manufacturer who does not include pixel mapping
in the menu system is evil!!!

No, that's just annoying. Disabling panorama mode unless you buy
their own brand of memory is evil.

Own brand memory card is just a smaller version of a proprietry mount and they all do that to the same level of evilness.. except guess who? LOL

 

[EMale]

I'm in 4/3 because of lenses. I have just two fast and sealed
lenses with minimum distortiona, CAs and wigneting for 28-400
range. Canon can't offer me that, Nicon can't offer me that. .
.there is no system which can offer me that.

24-105 IS + USM

Is that the canon lens with 5 stops worth of vignetting?

and 100-400 IS + USM will do just that, for the
Canon camp.

Yeah, for £680 and £1050 respectively... he'd pay £450 and £700 respectively for the DZs! Was someone hammering 4/3rds before over lens pricing?

Plus they're f4 + f4-5.6 lenses.. he was talking about f2.8-3.5 gear! What he gets in light gathering abilities... you get in anti-shake. Snakes and ladders!

 

[EMale]

I think a more interesting discussion is what will be the impact of
the offset microlens sensor on the future of digital photography.

I've been advocating offset microlenses for years. Now Kodak, Oly's
original four thirds (tm) partner, is supplying such a sensor to
Leica.

http://www.dpreview.com/news/0609/06091501kodakccdleicam8.asp

An offset microlens sensor negates the arguments about needing new
"near telecentric" lenses for digital photography.

As that's what they'd need to handle. They'd have to take the light from a 7(14) mm wide angles to a 500(1000) mm tele!

Can they do it? I'd think the wide angles would be difficult without some form of telecentricity on the lenses if you wanted to avoid vignetting? But you'd know more about it than me.