Resolution vs format.

[Tony Beach]

Jack Hogan wrote: Vertical/Horizontal hand shake, for instance, affects the smaller format proportionally more, all else equivalent.

All else isn't equivalent though. Focal length for any given FOV is greater for the larger format so that will magnify any shake more.

There is an easy way to visualize the compromises involved in equivalence: insert the mFT sensor half-way between the lens and a FF sensor. Now move both sensors up and down the same absolute amount. Which image is affected more?

The issue is that a longer lens (not so much for the short focal lengths hypothesized below) is going to move more than a shorter lens; it's not about the sensor moving differently, it could even not move hardly at all and essentially the same on both formats and this would still be an issue of longer focal lengths magnifying shake more and being more prone to vibration.

From this article :

On top of that the longer focal length is a bigger lens, unless we are compensating for maximum apertures, so on telephoto lenses that's likely to add to shaky handling.

Of course there is going to be a size/weight sweet-spot for the given application, the D500+500mm/5.6 PF being right in there for birding for instance.

But to put a finer point on it, my birding friends remind me that "there's no substitute for square mm of pupil area". Once you start with that premise, equivalent lenses end up pretty well having similar bulk/weight/cost on all real photography formats.

Yes, but a shorter lens that is heavy is still going to be less shaky than a longer lens that is equally heavy.

If they don't it's because the relative manufacturer has taken shortcuts, hoping that its intended audience will not notice that they are no longer comparing apples to apples vs the competition

As much as I agree with you here, that's a different issue.

 

[Tony Beach]

If the sensors have the same number of pixels they will be able to capture the same number of lines.

If the sensors have the same pixel size it depends on what the limiting factor was for the smaller sensor:

• If the pixel size was limiting, then the larger sensor will be able to capture more lines
• If the lens was the limiting factor, then the larger sensor will capture the same number of lines.

Correct except that a lens doesn't have to be twice as sharp to accomplish this in the real world we live in now, so maybe that becomes an issue in a higher MP future.

So you’re saying that the lenses are not currently the limiting factor in sharpness,

Not the good ones.

so going to a smaller format might require sharper lenses to keep the same result, but they don’t have to be sharper by a factor equal the crop factor.

Diffraction is more of an issue, so as a practical matter and with good enough lenses it will be a matter of the lenses' performance at the equivalent stops on the each format.

 

[Jack Hogan]

Yes, but a shorter lens that is heavy is still going to be less shaky than a longer lens that is equally heavy.

Well, it depends how heavy, how long etc. Despite the simplified diagram above (they don't actually design teles like that, longer focal length does not necessarily mean a proportionately longer lens in practice, see for instance Nikon's 300 and 500mm PFs.

Once one gets into competitive tele territory, there isn't much one can do to shave cost/bulk/weight without compromising IQ, independently of format.

 

[Tony Beach]

Yes, but a shorter lens that is heavy is still going to be less shaky than a longer lens that is equally heavy.

Well, it depends how heavy, how long etc. Despite the simplified diagram above (they don't actually design teles like that, longer focal length does not necessarily mean a proportionately longer lens in practice, see for instance Nikon's 300 and 500mm PFs.

Okay, let's take those examples:

Nikon AF-S NIKKOR 300mm f/4E PF ED VR Lens

• 147.5 mm long
• 755 grams

Nikon AF-S NIKKOR 500mm f/5.6E PF ED VR Lens

• 237 mm long
• 1460 grams

In this case both the length and weight of the 500mm lens is a great deal more than the 300mm lens.

Once one gets into competitive tele territory, there isn't much one can do to shave cost/bulk/weight without compromising IQ, independently of format.

Sure, and again I agree with you here, but nonetheless:

Nikon AF-S NIKKOR 200mm f/2G ED VR II Lens

• 203 mm long

Nikon AF-S NIKKOR 300mm f/2.8G ED VR II Lens

• 267.5 mm long

In this case the length increased enough on the longer focal length lens to make a difference in the torque experienced at either end away from the fulcrum.

As to your point, both of the bottom two lenses weigh exactly the same, have exactly the same girth, and both cost over $5000 (the shorter one is actually $200 more expensive at B&H where I got these number from).

As to my point, I'm sure you can agree that torque is a factor when it comes to stability.

 

[Jack Hogan]

Yes, but a shorter lens that is heavy is still going to be less shaky than a longer lens that is equally heavy.

Well, it depends how heavy, how long etc. Despite the simplified diagram above (they don't actually design teles like that, longer focal length does not necessarily mean a proportionately longer lens in practice, see for instance Nikon's 300 and 500mm PFs.

Okay, let's take those examples:

Nikon AF-S NIKKOR 300mm f/4E PF ED VR Lens

• 147.5 mm long
• 755 grams
• $2000

Nikon AF-S NIKKOR 500mm f/5.6E PF ED VR Lens

• 237 mm long
• 1460 grams
• $3500

In this case both the length and weight of the 500mm lens is a great deal more than the 300mm lens.

Of course I agree with that Tony - and the fact that a 300mm should be easier to handle than a 500mm on the same camera aotbe.

But I thought that this thread was about different formats so my comments were made in that context. I was thinking for instance of uFT and the

Leica DG 200mm f/2.8 (260mm/3.7 on APS-C, 400mm/5.6 on FF)

• 174 mm long
• 1245 g
• $3000

or the

Olympus 300mm f/4.0 IS Pro ED M.Zuiko Digital (390mm/5.2 APS-C, 600mm/8 FF)

• 227mm
• 1270 g
• $2500

Similar bulk and weight (and price, ignoring marketing) for similar performance, there isn't much escaping physics. If one wants a competitive Tele one pays for it, in all three dimensions.

Jack

Once one gets into competitive tele territory, there isn't much one can do to shave cost/bulk/weight without compromising IQ, independently of format.

 

[Tony Beach]

Yes, but a shorter lens that is heavy is still going to be less shaky than a longer lens that is equally heavy.

Well, it depends how heavy, how long etc. Despite the simplified diagram above (they don't actually design teles like that, longer focal length does not necessarily mean a proportionately longer lens in practice, see for instance Nikon's 300 and 500mm PFs.

Okay, let's take those examples:

Nikon AF-S NIKKOR 300mm f/4E PF ED VR Lens

• 147.5 mm long
• 755 grams
• $2000

Nikon AF-S NIKKOR 500mm f/5.6E PF ED VR Lens

• 237 mm long
• 1460 grams
• $3500

In this case both the length and weight of the 500mm lens is a great deal more than the 300mm lens.

Just to be clear, you added the price here to those lenses.

Of course I agree with that Tony - and the fact that a 300mm should be easier to handle than a 500mm on the same camera aotbe.

Those were your examples, otherwise I wouldn't have even looked at them as they are not truly equivalent. I do have more to say about this at the end of this post though.

But I thought that this thread was about different formats so my comments were in that context.

Nikon has two different formats, and one could even go with a D500 and D5 with the same number of pixels or a D850 and a D500 with the same pixel density.

I was thinking for instance of uFT and the

Leica DG 200mm f/2.8 (260mm/3.7 on APS-C, 400mm/5.6 on FF)

• 174 mm long
• 1245 g
• $3000

or the

• Olympus 300mm f/4.0 IS Pro ED M.Zuiko Digital (390mm/5.2 APS-C, 600mm/8 FF)
• 227mm
• 1270 g
• $2500

Similar bulk and weight (and price, ignoring marketing) for similar performance, there isn't much escaping physics. If one wants a competitive Tele one pays for it, in all three dimensions.

From a post I made two months ago at Imaging Resource:

In response to:

"Increase the size of the recording medium, you must increase the size of the lens necessary to provide a specific angle of view."

I wrote:

"Actually, you are increasing the focal length, not necessarily the size. For example, the Olympus M.Zuiko 40-150/2.8 is heavier and larger than the Nikon AF-P Nikkor 70-300/4.5-5.6 and the latter has the same or larger aperture diameter at every equivalent focal length."

I didn't even take note of this at the time, but that Olympus lens is actually longer than that Nikon lens (160mm compared to 146mm), not to mention less expensive (but that could be related to better optics, which isn't actually what I set out either here or there to discuss).

 

[TheGrammarFairy]

Unless we are lucky enough to get a visit from AiryDiscus, your best bet is to do a search at the LensRentals.com blog. The proprietor of that site has done some definitive testing of micro 4/3 lenses with relevant commentary on resolution.

Real world results will vary depending on how disciplined you are at keeping the camera rock solid, avoiding shutter vibrations, and focusing accurately.

It is very easy to make a great lens look bad but hard to make a pretty good lens look excellent, though it is entirely possible.

Well, lenses for 'small' formats can be expensive enough, so maybe you could also say that they make a lot of money on lenses ;-) But are you saying that if for example comparing FF and mFT lenses, then mFT lenses will be sharper as a general rule (with exceptions) if measured as lp/mm on sensors with same pixel size, but not quite sharp enough to resolve the same lp/ph (or lw/ph) as FF lenses if tested on cameras with same vertical pixel count? If so, that's my impression too.