How big would a 100-200 f2.8 m43 OIS be?

OniMirage said:

OniMirage wrote:

OniMirage said:

ginsbu wrote:

OniMirage said:

OniMirage wrote:

OniMirage said:

ginsbu wrote:

OniMirage said:

OniMirage wrote:

OniMirage said:

tt321 wrote:

However, what is the reason for constant max apertures? It's not as if these lenses are controlled by mechanical aperture rings with numerical markings, so ease of operation does not apply. With modern feedback controlled flashguns, the flash control motivation is also removed or significantly weakened. The only possible remaining reason for this would be marketing.

Marketing has got to such a degree that customers, when stating technical desires, are including pure marketing items in their wish lists!

Click to expand...

Why would it be a marketing ploy to design a lens that never changes aperture? I am actually not sure I understand how you can't see a constant aperture as desirable.

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If you had the choice between, e.g., a 100–200mm f/4 or a 100–200mm f/2.8–4 of approximately the same size and optical performance, which would you prefer?

It's not quite a free lunch — the faster aperture at the wide end might require additional optical correction — but lens size for telephotos is primarily driven by maximum focal length and aperture at that focal length, so it's pretty close.

For WA zooms, things are more complicated, but I think the case for a 12–60mm f/2.8–4 over f/4-constant is very strong. If you don't like f/2.8 on the wide end, you can always stop down!

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I wouldn't choose either because I would choose the lens we are discussing in the topic, a 100-200 f2.8. So aside from having to purchase the lens, it would in fact be a free lunch for me.

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tt321 made a general point, which you questioned; I answered your question in general terms, including an example for illustrative purposes only (note the 'e.g.'). Complaining about the specific example doesn't address the general point tt321 was making or my answer to your question about it.

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That's fine but I am waiting on tt321 to answer why he thought it was a marketing ploy. Your response was not an answer to that but it did serve the purpose of a distraction. Was that the point?

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No distraction: The point was that if you don't want the wider aperture on the wide end, you can always stop down and use the lens as if it has a constant aperture (as I said); the user who wants a constant aperture loses nothing from having a variable aperture design with better speed on the wide end. With a constant aperture design, users who might make use of a wider aperture on the wide end are deprived of that opportunity, but the marketing folks with surely tout "advantage" of the constant aperture.

OniMirage said:

OniMirage wrote:

OniMirage said:

clengman wrote:

OniMirage said:

OniMirage wrote:

OniMirage said:

ginsbu wrote:

OniMirage said:

OniMirage wrote:

OniMirage said:

tt321 wrote:

However, what is the reason for constant max apertures? It's not as if these lenses are controlled by mechanical aperture rings with numerical markings, so ease of operation does not apply. With modern feedback controlled flashguns, the flash control motivation is also removed or significantly weakened. The only possible remaining reason for this would be marketing.

Marketing has got to such a degree that customers, when stating technical desires, are including pure marketing items in their wish lists!

Click to expand...

Why would it be a marketing ploy to design a lens that never changes aperture? I am actually not sure I understand how you can't see a constant aperture as desirable.

Click to expand...

If you had the choice between, e.g., a 100–200mm f/4 or a 100–200mm f/2.8–4 of approximately the same size and optical performance, which would you prefer?

It's not quite a free lunch — the faster aperture at the wide end might require additional optical correction — but lens size for telephotos is primarily driven by maximum focal length and aperture at that focal length, so it's pretty close.

For WA zooms, things are more complicated, but I think the case for a 12–60mm f/2.8–4 over f/4-constant is very strong. If you don't like f/2.8 on the wide end, you can always stop down!

Click to expand...

I wouldn't choose either because I would choose the lens we are discussing in the topic, a 100-200 f2.8. So aside from having to purchase the lens, it would in fact be a free lunch for me.

Click to expand...

The point that you're missing is if you set out to make a 100-200mm zoom that's f/2.8 at 200mm, there's little or no reason not to make it variable aperture with f/1.4 at the short end. You would prefer f/1.4-2.8 to f/2.8 constant, wouldn't you?

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That would depend on the quality of the images possible on the wider end. In order to gain that fast speed what am I losing.

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Usually little to nothing. The wide end will likely have poorer IQ wide open than in a constant aperture design, but stopped down to the same aperture IQ will usually be similar. Depending on the lens type the faster aperture on the wide end might add size or weight, but this is generally not the case for telephoto zooms.

ginsbu said:

ginsbu wrote:

ginsbu said:

OniMirage wrote:

ginsbu said:

ginsbu wrote:

ginsbu said:

OniMirage wrote:

ginsbu said:

ginsbu wrote:

ginsbu said:

OniMirage wrote:

ginsbu said:

tt321 wrote:

However, what is the reason for constant max apertures? It's not as if these lenses are controlled by mechanical aperture rings with numerical markings, so ease of operation does not apply. With modern feedback controlled flashguns, the flash control motivation is also removed or significantly weakened. The only possible remaining reason for this would be marketing.

Marketing has got to such a degree that customers, when stating technical desires, are including pure marketing items in their wish lists!

Click to expand...

Why would it be a marketing ploy to design a lens that never changes aperture? I am actually not sure I understand how you can't see a constant aperture as desirable.

Click to expand...

If you had the choice between, e.g., a 100–200mm f/4 or a 100–200mm f/2.8–4 of approximately the same size and optical performance, which would you prefer?

It's not quite a free lunch — the faster aperture at the wide end might require additional optical correction — but lens size for telephotos is primarily driven by maximum focal length and aperture at that focal length, so it's pretty close.

For WA zooms, things are more complicated, but I think the case for a 12–60mm f/2.8–4 over f/4-constant is very strong. If you don't like f/2.8 on the wide end, you can always stop down!

Click to expand...

I wouldn't choose either because I would choose the lens we are discussing in the topic, a 100-200 f2.8. So aside from having to purchase the lens, it would in fact be a free lunch for me.

Click to expand...

tt321 made a general point, which you questioned; I answered your question in general terms, including an example for illustrative purposes only (note the 'e.g.'). Complaining about the specific example doesn't address the general point tt321 was making or my answer to your question about it.

Click to expand...

That's fine but I am waiting on tt321 to answer why he thought it was a marketing ploy. Your response was not an answer to that but it did serve the purpose of a distraction. Was that the point?

Click to expand...

No distraction: The point was that if you don't want the wider aperture on the wide end, you can always stop down and use the lens as if it has a constant aperture (as I said); the user who wants a constant aperture loses nothing from having a variable aperture design with better speed on the wide end. With a constant aperture design, users who might make use of a wider aperture on the wide end are deprived of that opportunity, but the marketing folks with surely tout "advantage" of the constant aperture.

Click to expand...

No distraction, but a strawman argument.

Most constant aperture zooms are a constant f/2.8, some a constant f/4. Constant aperture zooms are nearly always fast from the get go. The desire for "constant aperture" zooms is a desire for fast zooms, period. Most people's complaint with variable aperture zooms is that they tend to be of the f/4.0-5.6 variety (f/3.5-4.5 on a good day.)

f/2.8-4.0 zooms are nice, but nowhere near as nice as a constant f/2.8. To make this argument in anyway relevant to a discussion of a constant f/2.8 zoom, show me a production variable aperture zoom that's f/2.8 at the long end.

Hoop99 said:

Hoop99 wrote:

Hoop99 said:

ginsbu wrote:

No distraction: The point was that if you don't want the wider aperture on the wide end, you can always stop down and use the lens as if it has a constant aperture (as I said); the user who wants a constant aperture loses nothing from having a variable aperture design with better speed on the wide end. With a constant aperture design, users who might make use of a wider aperture on the wide end are deprived of that opportunity, but the marketing folks with surely tout "advantage" of the constant aperture.

Click to expand...

No distraction, but a strawman argument.

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Certainly not!

Hoop99 said:

Most constant aperture zooms are a constant f/2.8, some a constant f/4. Constant aperture zooms are nearly always fast from the get go. The desire for "constant aperture" zooms is a desire for fast zooms, period. Most people's complaint with variable aperture zooms is that they tend to be of the f/4.0-5.6 variety (f/3.5-4.5 on a good day.)

f/2.8-4.0 zooms are nice, but nowhere near as nice as a constant f/2.8. To make this argument in anyway relevant to a discussion of a constant f/2.8 zoom, show me a production variable aperture zoom that's f/2.8 at the long end.

Click to expand...

You are linking two independent issues: constant vs variable aperture, and lens speed. The fact that "desire for "constant aperture" zooms is a desire for fast zooms" is exactly the problem! Manufacturers have made it so by not making (for SLRs) fast variable-aperture zooms, but it doesn't have to be that way. The point is that these issues should be separated and it would be to users' advantage if they were.

As you may know, Olympus has made some very fine constant-f/2 zooms. But f/2 on the long end made them very large. Compared to a constant-f/2.8 design, a variable f/2–2.8 design has the potential to be get an extra stop of lens speed on the short end in a similarly sized package. Oly's technical achievement with their f/2 zooms strongly suggests that they could build such a lens if they wanted to.

ginsbu said:

ginsbu wrote:

ginsbu said:

Hoop99 wrote:

ginsbu said:

ginsbu wrote:

No distraction: The point was that if you don't want the wider aperture on the wide end, you can always stop down and use the lens as if it has a constant aperture (as I said); the user who wants a constant aperture loses nothing from having a variable aperture design with better speed on the wide end. With a constant aperture design, users who might make use of a wider aperture on the wide end are deprived of that opportunity, but the marketing folks with surely tout "advantage" of the constant aperture.

Click to expand...

No distraction, but a strawman argument.

Click to expand...

Certainly not!

ginsbu said:

Most constant aperture zooms are a constant f/2.8, some a constant f/4. Constant aperture zooms are nearly always fast from the get go. The desire for "constant aperture" zooms is a desire for fast zooms, period. Most people's complaint with variable aperture zooms is that they tend to be of the f/4.0-5.6 variety (f/3.5-4.5 on a good day.)

f/2.8-4.0 zooms are nice, but nowhere near as nice as a constant f/2.8. To make this argument in anyway relevant to a discussion of a constant f/2.8 zoom, show me a production variable aperture zoom that's f/2.8 at the long end.

Click to expand...

You are linking two independent issues: constant vs variable aperture, and lens speed. The fact that "desire for "constant aperture" zooms is a desire for fast zooms" is exactly the problem! Manufacturers have made it so by not making (for SLRs) fast variable-aperture zooms, but it doesn't have to be that way. The point is that these issues should be separated and it would be to users' advantage if they were.

As you may know, Olympus has made some very fine constant-f/2 zooms. But f/2 on the long end made them very large. Compared to a constant-f/2.8 design, a variable f/2–2.8 design has the potential to be get an extra stop of lens speed on the short end in a similarly sized package. Oly's technical achievement with their f/2 zooms strongly suggests that they could build such a lens if they wanted to.

Click to expand...

Again, show me an f/2.0-2.8 zoom. If someone releases one for a system I shoot, I would gladly consider it, but f/2 zooms, constant or not, are exceedingly rare birds.

About the only place I can recall your argument taking on anything but a tangential relevance is in the case of a handful of UWA zooms from Sigma and Nikon i.e., the "consumer" 10-24mm f/3.5-4.5 versus the "pro" 12-24mm f/4.

Further, whatever the merits of a f/2.0-2.8 zoom may or may not be, they have no bearing on the OP's original inquiry into a 100-200mm f/2.8. It's simply hijacking the thread to argue the merits of a piece of vaporware while taking a backhanded swipe at all of us rubes so thoroughly duped by the marketing collusion of every major lens manufacturer out there.

Hoop99 said:

Hoop99 wrote:

Hoop99 said:

ginsbu wrote:

Hoop99 said:

Hoop99 wrote:

Hoop99 said:

ginsbu wrote:

No distraction: The point was that if you don't want the wider aperture on the wide end, you can always stop down and use the lens as if it has a constant aperture (as I said); the user who wants a constant aperture loses nothing from having a variable aperture design with better speed on the wide end. With a constant aperture design, users who might make use of a wider aperture on the wide end are deprived of that opportunity, but the marketing folks with surely tout "advantage" of the constant aperture.

Click to expand...

No distraction, but a strawman argument.

Click to expand...

Certainly not!

Hoop99 said:

Most constant aperture zooms are a constant f/2.8, some a constant f/4. Constant aperture zooms are nearly always fast from the get go. The desire for "constant aperture" zooms is a desire for fast zooms, period. Most people's complaint with variable aperture zooms is that they tend to be of the f/4.0-5.6 variety (f/3.5-4.5 on a good day.)

f/2.8-4.0 zooms are nice, but nowhere near as nice as a constant f/2.8. To make this argument in anyway relevant to a discussion of a constant f/2.8 zoom, show me a production variable aperture zoom that's f/2.8 at the long end.

Click to expand...

You are linking two independent issues: constant vs variable aperture, and lens speed. The fact that "desire for "constant aperture" zooms is a desire for fast zooms" is exactly the problem! Manufacturers have made it so by not making (for SLRs) fast variable-aperture zooms, but it doesn't have to be that way. The point is that these issues should be separated and it would be to users' advantage if they were.

As you may know, Olympus has made some very fine constant-f/2 zooms. But f/2 on the long end made them very large. Compared to a constant-f/2.8 design, a variable f/2–2.8 design has the potential to be get an extra stop of lens speed on the short end in a similarly sized package. Oly's technical achievement with their f/2 zooms strongly suggests that they could build such a lens if they wanted to.

Click to expand...

Again, show me an f/2.0-2.8 zoom. If someone releases one for a system I shoot, I would gladly consider it, but f/2 zooms, constant or not, are exceedingly rare birds.

About the only place I can recall your argument taking on anything but a tangential relevance is in the case of a handful of UWA zooms from Sigma and Nikon i.e., the "consumer" 10-24mm f/3.5-4.5 versus the "pro" 12-24mm f/4.

Further, whatever the merits of a f/2.0-2.8 zoom may or may not be, they have no bearing on the OP's original inquiry into a 100-200mm f/2.8. It's simply hijacking the thread to argue the merits of a piece of vaporware while taking a backhanded swipe at all of us rubes so thoroughly duped by the marketing collusion of every major lens manufacturer out there.

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I did not initiate this particular subthread and anyone who isn't interested is welcome to skip it: this is the virtue of a threaded forum.

Nor have I taken a "backhanded swipe" at anyone (I did not make the original remark about constant apertures being a marketing ploy). I have simply disputed the claim made by others that constant aperture designs are preferable.

The "vaporware" charge is particularly out of place. The OP asked about the size of a hypothetical constant aperture lens. It is not off topic — much less "hijacking" — to point out that a variable aperture design could offer a faster aperture on the wide end without being notably larger. If we're going to ponder a possible len design, why not ponder the possibility of a better one?

Finally, demanding to see an f/2.0-2.8 zoom before you consider the argument relevant is an unsubstantiated dodge. That such designs there haven't been produced just reflects the dominance of larger formats until very recently. It's not surprising that manufacturers wedded to 135 format haven't made f/2 zooms (constant or otherwise): it's hard to build fast (zoom) lenses for larger formats. One of the advantages of smaller formats is that making fast zoom lenses becomes more practical. Oly did it with their f/2 zooms, and compact cameras are now available with good quality zooms sporting f/2.8 or faster apertures on the long end. To refuse to discuss such possibilities is to refuse to discuss the potential advantages of smaller formats.

Alan_W1 said:

Alan_W1 wrote:

Alan_W1 said:

ginsbu wrote:

Alan_W1 said:

oklaphotog wrote:

Alan_W1 said:

ginsbu wrote:

If you had the choice between, e.g., a 100–200mm f/4 or a 100–200mm f/2.8–4 of approximately the same size and optical performance, which would you prefer?

Click to expand...

Neither as a 100-200 needs to be F2.8 @ 200 as to allow good use of a 2x TC.

Click to expand...

You make a lot of good points in your reply, but you're missing (or avoiding) the point I was making. The topic being discussed in my reply was a general one about variable versus constant aperture zooms. Size and weight for telephoto zooms are driven by FL and aperture at the long end; a variable aperture design (potentially) allows for a faster aperture at the short end without an appreciable increase in size or weight — so why favor constant aperture designs in general?

Click to expand...

Some good points being made from all sides, regarding variable apertures.

I think constant aperture zooms were preferable during the film era, where everyone used manual exposure, and manual flash.

With todays automation, i suspect there is less need for constant aperture zooms for many, and although i always use tele primes, if i were to aquire a tele zoom today, i would still prefer a constant aperture throughout its range.....as i remain a manual exposure user exclusively {including flash}.

Personally, i consider a 200-400 f4 constant aperture to be the only tele zoom that would tempt me away from prime teles {ideal compromise for wildlife video & stills, for me}, although as a tripod/monopod user, i don't feel a need for small & light.

Click to expand...

In manual aperture modes (M and A), only when you use the lens wide open would the aperture change when you zoom. If you set an aperture which exists for the entire zoom range (e.g. f5.6 in a 3.5-5.6 lens), the lens behaves the same as a constant max aperture zoom, i.e. keeping to f5.6 wherever you zoom. This presents zero problems with manual exposure flash or no flash.

So imagine a variable aperture lens with the same max aperture at the long end as your constant aperture one, but no added weight/size/price, the larger apertures at the wide end would be purely bonus, for situations where they could be useful. Why not have them?

Say that 100-200/2.8 is compared with a 100-200/2-2.8. Which one would you get?

The intuitive allegation that a lens with a wider max aperture at the wide end would have worse optical performance than a constant aperture one is without factual basis.

tt321 said:

tt321 wrote:

tt321 said:

Alan_W1 wrote:

tt321 said:

ginsbu wrote:

tt321 said:

oklaphotog wrote:

tt321 said:

ginsbu wrote:

If you had the choice between, e.g., a 100–200mm f/4 or a 100–200mm f/2.8–4 of approximately the same size and optical performance, which would you prefer?

Click to expand...

Neither as a 100-200 needs to be F2.8 @ 200 as to allow good use of a 2x TC.

Click to expand...

You make a lot of good points in your reply, but you're missing (or avoiding) the point I was making. The topic being discussed in my reply was a general one about variable versus constant aperture zooms. Size and weight for telephoto zooms are driven by FL and aperture at the long end; a variable aperture design (potentially) allows for a faster aperture at the short end without an appreciable increase in size or weight — so why favor constant aperture designs in general?

Click to expand...

Some good points being made from all sides, regarding variable apertures.

I think constant aperture zooms were preferable during the film era, where everyone used manual exposure, and manual flash.

With todays automation, i suspect there is less need for constant aperture zooms for many, and although i always use tele primes, if i were to aquire a tele zoom today, i would still prefer a constant aperture throughout its range.....as i remain a manual exposure user exclusively {including flash}.

Personally, i consider a 200-400 f4 constant aperture to be the only tele zoom that would tempt me away from prime teles {ideal compromise for wildlife video & stills, for me}, although as a tripod/monopod user, i don't feel a need for small & light.

Click to expand...

In manual aperture modes (M and A), only when you use the lens wide open would the aperture change when you zoom. If you set an aperture which exists for the entire zoom range (e.g. f5.6 in a 3.5-5.6 lens), the lens behaves the same as a constant max aperture zoom, i.e. keeping to f5.6 wherever you zoom. This presents zero problems with manual exposure flash or no flash.

Click to expand...

As i mentioned....today there is probably less need for constant aperture zooms for many.

My views are based on my area of interest only {wildlife photography}

In the film era, stopping down a variable lens to a constant aperture throughout, may present some difficulties with varying dof at each end of the range, and difficulties with shutter speeds, due to the commonly used ASA film ratings in those days { 50/64/125}, and therefore shooting wide open would be a regular choice with moving subjects/wildlife etc. This would also affect flash settings, as working by GN's were the norm {and full flash was far more common than fill, due to slow syncs}.

In reality, tele zooms were rarely prefered over tele primes, so not an issue for me in those days. I think the only zoom i owned in those days was a Kiron 30-80mm.....well built, but rarely used.



So imagine a variable aperture lens with the same max aperture at the long end as your constant aperture one, but no added weight/size/price, the larger apertures at the wide end would be purely bonus, for situations where they could be useful. Why not have them?

I would have one....if one existed {but i'm not holding my breath}. At present a 200-400mm f4 does exist, and therefore is tempting to me { if i can raise the cash for a SH one}......mounted on a tripod, it would serve me well. Bear in mind also that light weight is not always an advantage......the appropriate tool for the job always takes priority.

tt321 said:

Say that 100-200/2.8 is compared with a 100-200/2-2.8. Which one would you get?

Click to expand...

Given the option, the latter, although neither would be of interest to me {but possibly to some users}.

tt321 said:

The intuitive allegation that a lens with a wider max aperture at the wide end would have worse optical performance than a constant aperture one is without factual basis.

Click to expand...

Alan_W1 said:

Alan_W1 wrote:

Alan_W1 said:

tt321 wrote:

Alan_W1 said:

Alan_W1 wrote:

Alan_W1 said:

ginsbu wrote:

Alan_W1 said:

oklaphotog wrote:

Alan_W1 said:

ginsbu wrote:

If you had the choice between, e.g., a 100–200mm f/4 or a 100–200mm f/2.8–4 of approximately the same size and optical performance, which would you prefer?

Click to expand...

Neither as a 100-200 needs to be F2.8 @ 200 as to allow good use of a 2x TC.

Click to expand...

You make a lot of good points in your reply, but you're missing (or avoiding) the point I was making. The topic being discussed in my reply was a general one about variable versus constant aperture zooms. Size and weight for telephoto zooms are driven by FL and aperture at the long end; a variable aperture design (potentially) allows for a faster aperture at the short end without an appreciable increase in size or weight — so why favor constant aperture designs in general?

Click to expand...

Some good points being made from all sides, regarding variable apertures.

I think constant aperture zooms were preferable during the film era, where everyone used manual exposure, and manual flash.

With todays automation, i suspect there is less need for constant aperture zooms for many, and although i always use tele primes, if i were to aquire a tele zoom today, i would still prefer a constant aperture throughout its range.....as i remain a manual exposure user exclusively {including flash}.

Personally, i consider a 200-400 f4 constant aperture to be the only tele zoom that would tempt me away from prime teles {ideal compromise for wildlife video & stills, for me}, although as a tripod/monopod user, i don't feel a need for small & light.

Click to expand...

In manual aperture modes (M and A), only when you use the lens wide open would the aperture change when you zoom. If you set an aperture which exists for the entire zoom range (e.g. f5.6 in a 3.5-5.6 lens), the lens behaves the same as a constant max aperture zoom, i.e. keeping to f5.6 wherever you zoom. This presents zero problems with manual exposure flash or no flash.

Click to expand...

As i mentioned....today there is probably less need for constant aperture zooms for many.

My views are based on my area of interest only {wildlife photography}

In the film era, stopping down a variable lens to a constant aperture throughout, may present some difficulties with varying dof at each end of the range, and difficulties with shutter speeds, due to the commonly used ASA film ratings in those days { 50/64/125}, and therefore shooting wide open would be a regular choice with moving subjects/wildlife etc. This would also affect flash settings, as working by GN's were the norm {and full flash was far more common than fill, due to slow syncs}.

Click to expand...

having just re-read my reply, i think my age has finally caught up with me, regarding the mention of dof....this would obviously apply equaly to a constant zoom and a variable zoom..stopped down. Although shooting wide open would still present the aforementioned problems {quite likely with those slowish films speeds in those days}.

My confusion springs from the fact that my only zoom in those days was actually a vari-focal lens.....which was far more of serious drawback than variable aperture zooms.

Alan_W1 said:

In reality, tele zooms were rarely prefered over tele primes, so not an issue for me in those days. I think the only zoom i owned in those days was a Kiron 30-80mm.....well built, but rarely used.

So imagine a variable aperture lens with the same max aperture at the long end as your constant aperture one, but no added weight/size/price, the larger apertures at the wide end would be purely bonus, for situations where they could be useful. Why not have them?

I would have one....if one existed {but i'm not holding my breath}. At present a 200-400mm f4 does exist, and therefore is tempting to me { if i can raise the cash for a SH one}......mounted on a tripod, it would serve me well. Bear in mind also that light weight is not always an advantage......the appropriate tool for the job always takes priority.

Alan_W1 said:

Say that 100-200/2.8 is compared with a 100-200/2-2.8. Which one would you get?

Click to expand...

Given the option, the latter, although neither would be of interest to me {but possibly to some users}.

Alan_W1 said:

The intuitive allegation that a lens with a wider max aperture at the wide end would have worse optical performance than a constant aperture one is without factual basis.

Click to expand...

Click to expand...

Alan_W1 said:

Alan_W1 wrote:

My confusion springs from the fact that my only zoom in those days was actually a vari-focal lens.....which was far more of serious drawback than variable aperture zooms.

Click to expand...

Indeed! However, so-called true zooms are in many cases only approximately so. You might get away with focusing at the long end then zoom out, but rarely with focusing at the wide end then zoom in...

I believe current M4/3 zooms tend to be quite liberal with regard of "true zoom" credentials, but greater DoF coming from the smaller format and fast AF mean that in practice, whether the zooms are very true matters less than during the mechanical everything age.

Anders W said:

Anders W wrote:

Click to expand...

Anders W said:

But the 45-200 can't really stand a comparison with the 100-300 for optical performance

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Well that is interesting. The reviews I have read of the 100-300 didn't show it to be obviously better than the 45-200 in overlapping range MTF (nor the 45-175 to be obviously worse). Seeing as the 45-175 "silver" was discounted heavily on US Amazon, I took a chance to reverse-import it (for 1/3 the local price of the 100-300) and will see how it goes. At the least, I will check closely for de-centering this time, and not hesitate to get it serviced while under warranty.

Anders W said:

Anders W wrote:

Oh. I see. So what nonsense have you read about shutter shock, and what camera, lens, and shutter speed did you use for your exhaustive test?

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I think this sentence is what I considered nonsense: "Long lenses are useless due to shutter shock."

I did not claim to do an exhaustive test. In the shots I mentioned, camera was Panasonic G10, lens was the 14-42mm kit zoom at 42mm, and shutter speed for f/7.1 was 2 seconds. Some were f/5.6 at 0.8 seconds.

I realize that 42mm (84mm equivalent) is not a very long focal length. And, even 0.8 seconds is too long to be the worst case for showing "shutter shock". The point I was making is that I didn't see the term "shutter shock" in posts before this, not even in posts about the 100-300mm zoom when it came out; many pictures I've seen from that lens at 300mm are very sharp; but now that the G5 is here and has electronic shutter we read that "long lenses are useless due to shutter shock".

I have the older 45mm-200mm, pleased enough with that for its price. Perhaps at the long end the shots are affected by shutter shock, but if so, I have not noticed. You are welcome to tell me that's my problem that I don't notice it, it's really there, and I should be unhappy about it.

IrishhAndy said:

IrishhAndy wrote

Long lenses are useless due to shutter shock. They can not be hand held.

Click to expand...

What does this even mean? Did you even think before you posted such utter nonsense?