[Edit] Comparison of the 50-200 f2.8 With the MC14 and MC20.

tammons said:

Rafael Rivera said:

CaliforniaDave said:

Rafael Rivera said:

The title and thread is misleading. 200 f/2.8 makes me think of a prime, and the only lens that fits that bill is the Panasonic Leica 200mm f/2.8 lens.

Only reason I chose to read this thread is because I thought it pertained to that lens, and I'm interested in learning more about the PL prime lens. Have zero interest in the OM 50-200 f/2.8 lens- actually negative interest given some of the more promotional posts listed here.

And yes, the MC14 and MC20 should have clued me in that this was an OM lens, but then I don't understand why the MC designation was included, but the '50-' part of the zoom lens was not.

Click to expand...

I had the same confusion as you - thought I was reading about the PL 200 f/2.8 lens and teleconverters, and didn’t realize otherwise until I read your response. In hindsight the MC should have been the giveaway. I bought a used PL 200 f/2.8 and 1.4X TC. I also have the 2.0X TC and the PL 50-200 and 100-400. What do you want to know? I have taken some test shots of charts and real subjects with all of them, and could start a new thread if it would be helpful.

These videos might be of help on the PL 200:

Click to expand...

No specific question- I own that lens, along with the 1.4x TC. I used to own the 2x TC as well, but found it wasn't as sharp as I would like. Was curious to see if this was an isolated issue to my TC, or more of a 2x TC issue. Suspect the former.

And thanks for the links. Will check out this weekend.

Click to expand...

Butting in. I have owned/tried the PL 200mm F2.8 three times. First time was the with the kit 1.4x. No 2x.

Second time I owned it, I had both TCs, and the IQ drop with the 2x was minimal and mostly CA, but it was still very sharp considering the 2x.

The third time I had both TCs, but this was the first time I got a bad copy of the Pana 2x TC. It was a real dog and very soft so I returned it. So, yes, there are bad Panasonic 2x TCs.

I now have another P 2x TC that I use with the Pana 100-400 and it is very sharp.

Click to expand...

Good to know. May pick up a new 2x TC for the 200mm lens, as it is one of my favorite MFT lenses.

Interesting you found the 2x TC sharp with the P100-400. I would have thought that by the apertures resulting from its use, you'd be heavily into diffraction territory by then, softening up the image.

tammons said:

Rafael Rivera said:

CaliforniaDave said:

Rafael Rivera said:

The title and thread is misleading. 200 f/2.8 makes me think of a prime, and the only lens that fits that bill is the Panasonic Leica 200mm f/2.8 lens.

Only reason I chose to read this thread is because I thought it pertained to that lens, and I'm interested in learning more about the PL prime lens. Have zero interest in the OM 50-200 f/2.8 lens- actually negative interest given some of the more promotional posts listed here.

And yes, the MC14 and MC20 should have clued me in that this was an OM lens, but then I don't understand why the MC designation was included, but the '50-' part of the zoom lens was not.

Click to expand...

I had the same confusion as you - thought I was reading about the PL 200 f/2.8 lens and teleconverters, and didn’t realize otherwise until I read your response. In hindsight the MC should have been the giveaway. I bought a used PL 200 f/2.8 and 1.4X TC. I also have the 2.0X TC and the PL 50-200 and 100-400. What do you want to know? I have taken some test shots of charts and real subjects with all of them, and could start a new thread if it would be helpful.

These videos might be of help on the PL 200:

Click to expand...

No specific question- I own that lens, along with the 1.4x TC. I used to own the 2x TC as well, but found it wasn't as sharp as I would like. Was curious to see if this was an isolated issue to my TC, or more of a 2x TC issue. Suspect the former.

And thanks for the links. Will check out this weekend.

Click to expand...

Butting in. I have owned/tried the PL 200mm F2.8 three times. First time was the with the kit 1.4x. No 2x.

Second time I owned it, I had both TCs, and the IQ drop with the 2x was minimal and mostly CA, but it was still very sharp considering the 2x.

The third time I had both TCs, but this was the first time I got a bad copy of the Pana 2x TC. It was a real dog and very soft so I returned it. So, yes, there are bad Panasonic 2x TCs.

I now have another P 2x TC that I use with the Pana 100-400 and it is very sharp.

Click to expand...

Good to know. May pick up a new 2x TC for the 200mm lens, as it is one of my favorite MFT lenses.

Interesting you found the 2x TC sharp with the P100-400. I would have thought that by the apertures resulting from its use, you'd be heavily into diffraction territory by then, softening up the image.

Apologies for the duplicate post. DPReview said it didn't go through, so I tried reposting- but it did go through the first (and second) time. Tom, if you have time, could you please delete the repost (and this one)? Thx in advance.

drj3 said:

Tom Caldwell said:

Rafael Rivera said:

The title and thread is misleading. 200 f/2.8 makes me think of a prime, and the only lens that fits that bill is the Panasonic Leica 200mm f/2.8 lens.

Only reason I chose to read this thread is because I thought it pertained to that lens, and I'm interested in learning more about the PL prime lens. Have zero interest in the OM 50-200 f/2.8 lens- actually negative interest given some of the more promotional posts listed here.

And yes, the MC14 and MC20 should have clued me in that this was an OM lens, but then I don't understand why the MC designation was included, but the '50-' part of the zoom lens was not.

Click to expand...

I have the PL 200/2.8 Prime and both TC units. I can't post comparison images for the time being but I can assure you that they make minimal degradation to the quality of the images. The TC units and tiny and fit snugly. Easy carry. The lens itself is internal focus. and is fairly heavy. It is a magnificent performer as might be both required and expected.

The 1.4x TC comes in the box and the 2.0x TC was quite expensive and rare. I had to buy mine from a Japanese vendor. Maybe they are easier to find now?

Some of these images were made with the GX9 + PL 200/2.8 + 1.4x TC - scroll down and check the EXIF readings.

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

Click to expand...

The problem with discussing how TCs affect resolution is how we measure resolution using a standard sized target at a distance that fills the frame. Using that measure of resolution, all TCs will reduce measured resolution by a very large degree. Any lens without a TC will have far greater resolution and detail when the standard target is photographed at a distance that fills the frame.

If, however, we look at detail when the lens and TCs are shot from the same distance, and we look at detail of the cropped lens image vs the uncropped TC images then a good TC matched to the lens will resolve more detail than the cropped image. However, even if that TC image is much better than the crop of that lens without a TC, it does not mean that the image will be a good image. A very sharp lens with a focal length equal to that of a lens with a TC will generally resolve more detail that the lens requiring the TC.

My preliminary evaluation of the MC20 on the 50-200 f2.8 image is somewhat better than a crop of the lens without the TC. However, that does not imply that the image is necessarily a good image. It may be that neither image taken at that distance has enough detail to be considered a good image and the only solution would be to get closer so that you have sufficient detail or use a lens which has higher measured resolution using the standard target at that focal length.

When I read comments about image quality with TCs I am somewhat unsure about how to interpret the statement.

I should also add that for most images, viewed as most individuals view them on their phone or PC monitor the resolution of the image is not very important. Most images without any enlargement really do not look that different when taken with any good lens (with or without a TC).

The thing that has actually impressed me the most about the 50-200 f2.8 is that I do notice the difference in the out of focus areas even on my PC monitor without any enlargement compared to my FTs 50-200 SWD.

Click to expand...

Thanks for your explanation.

The only images i have handy to link for comparison are images 5-10 in the following link (duplicated frommy previous post)

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

In this case they are all GX9+PL 200/2.8+1.4xTC

By comparison images 1-4 were made using the excellent Olympus 40-150/2.8 without TC assistance.

I was performing a service recording a show by stills photography and the camera/lens combinations were geared to capture different focal length captures as the dress rehearsal progressed. Not to specifically create images for evaluation of TC capability.

Obviously the made for purpose 1.4x TC was quite capable enough for the captures required.

Tom Caldwell said:

drj3 said:

Tom Caldwell said:

Rafael Rivera said:

The title and thread is misleading. 200 f/2.8 makes me think of a prime, and the only lens that fits that bill is the Panasonic Leica 200mm f/2.8 lens.

Only reason I chose to read this thread is because I thought it pertained to that lens, and I'm interested in learning more about the PL prime lens. Have zero interest in the OM 50-200 f/2.8 lens- actually negative interest given some of the more promotional posts listed here.

And yes, the MC14 and MC20 should have clued me in that this was an OM lens, but then I don't understand why the MC designation was included, but the '50-' part of the zoom lens was not.

Click to expand...

I have the PL 200/2.8 Prime and both TC units. I can't post comparison images for the time being but I can assure you that they make minimal degradation to the quality of the images. The TC units and tiny and fit snugly. Easy carry. The lens itself is internal focus. and is fairly heavy. It is a magnificent performer as might be both required and expected.

The 1.4x TC comes in the box and the 2.0x TC was quite expensive and rare. I had to buy mine from a Japanese vendor. Maybe they are easier to find now?

Some of these images were made with the GX9 + PL 200/2.8 + 1.4x TC - scroll down and check the EXIF readings.

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

Click to expand...

The problem with discussing how TCs affect resolution is how we measure resolution using a standard sized target at a distance that fills the frame. Using that measure of resolution, all TCs will reduce measured resolution by a very large degree. Any lens without a TC will have far greater resolution and detail when the standard target is photographed at a distance that fills the frame.

If, however, we look at detail when the lens and TCs are shot from the same distance, and we look at detail of the cropped lens image vs the uncropped TC images then a good TC matched to the lens will resolve more detail than the cropped image. However, even if that TC image is much better than the crop of that lens without a TC, it does not mean that the image will be a good image. A very sharp lens with a focal length equal to that of a lens with a TC will generally resolve more detail that the lens requiring the TC.

My preliminary evaluation of the MC20 on the 50-200 f2.8 image is somewhat better than a crop of the lens without the TC. However, that does not imply that the image is necessarily a good image. It may be that neither image taken at that distance has enough detail to be considered a good image and the only solution would be to get closer so that you have sufficient detail or use a lens which has higher measured resolution using the standard target at that focal length.

When I read comments about image quality with TCs I am somewhat unsure about how to interpret the statement.

I should also add that for most images, viewed as most individuals view them on their phone or PC monitor the resolution of the image is not very important. Most images without any enlargement really do not look that different when taken with any good lens (with or without a TC).

The thing that has actually impressed me the most about the 50-200 f2.8 is that I do notice the difference in the out of focus areas even on my PC monitor without any enlargement compared to my FTs 50-200 SWD.

Click to expand...

Thanks for your explanation.

The only images i have handy to link for comparison are images 5-10 in the following link (duplicated frommy previous post)

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

In this case they are all GX9+PL 200/2.8+1.4xTC

By comparison images 1-4 were made using the excellent Olympus 40-150/2.8 without TC assistance.

I was performing a service recording a show by stills photography and the camera/lens combinations were geared to capture different focal length captures as the dress rehearsal progressed. Not to specifically create images for evaluation of TC capability.

Obviously the made for purpose 1.4x TC was quite capable enough for the captures required.

Click to expand...

I think some lenses (the Panasonic 200 f2.8 and the Olympus 300mm f4) may actually out resolve the sensor without a TC which may account for their excellent performance with TCs. If you look at LensTip resolutions for the 200 f2.8 with the 1.4TC it may indeed have similar resolution (difficult to know since they were tested with different sensors) to the 40-150 f2.8 without a TC.

My response was not really specific to your comparison, but a more general comment about how we describe lens performance with TCs. Most statements, including those of "reviewers" on the web say things like "there is no performance hit" with a 1.4TC. I am never sure what that statement means.

The TC image will have less detail than the bare lens when the target fills the frame on both (different distances), but it may have "worse performance", or "no performance hit" (no different from a crop) or "better detail" when both are used at the same distance. I think your 200mm f2.8 falls into the "better detail" category

None of the above will indicate anything about how the lens performs compared to other lenses. Your comparison does help with that for the specific lenses.

I used to have the same idea about TC use - that the extra glass would always degrade the lens performance - even if only slightly.

Then I read that some lenses actually have a focal reduction optical set built in to the lens design. Brian Caldwell (no relation) has always averred that a good focal reduction designed optic will always improve the image quality of a lens that it is attached to.

Unlike a TC which has to be specifically designed per lens.

This leads to the assertions that teleconverters always work better if they are designed specifically for a particular lens or lenses. Much better than a generic converter can do when it can be mounted on many lenses.

Then there is the fact that many TC units have knobs and other protrusions that limit their mounting to specific lenses made by an oem manufacturer. There is good reason for this and it is not all manufacturer greed.

Of course most tight fisted owners would prefer just one set of TC converters in a drawer that would fit most of their lenses and don't care that much if many of their lenses are somewhat degraded by using them in conjunction. Canon seems to have managed to brush away its quite expensive set of 1.4x and 2.0x EF TC units as being suitable for a vast number of their EF mount lenses. There are only two TC available for EF and they have to serve many EF lenses.

The observation that TC units could reduce the quality of a lens it was attached to has kept me away from TC use. However if a 1.4x TC was specifically designed as an optical block to convert a lens such as the PL 200mm f2.8 into a veritable 280mm f4.0 as if designed as such then surely it will act and image like a 280/4.0 as if it had been made as a single lens?

Likewise the PL 200/2.8 + PL 2.0x TC should act just like a made 400mm f6.3 and not degraded version with common or garden TC built for mass lens use.

I don't know enough as optic quality is not something I have deep knowledge of - but I read a lot and I can regurgitate some of the written wisdom of others.

The same set of TC units can be used on the PL 50-200mm (when released) and their 100-400mm II (as an afterthought). I don't know the former but could consider that one set of TC could be designed for use specifically on another lens. However I have the latter and consider the 2.0 TC on that lens a bit of a waste of time.

--
Tom Caldwell

Thank you for your close-up testing drj3. I had time to shoot some outdoor comparisons yesterday at longer working distances. The distance is approximately 50m on a cool morning. I shot the bare lens at 200mm, then with the MC-14 and the MC-20 to compare.

You can see in the upper left corner what are of the image we are looking at. I tried to match them to approximate viewing size.


Bare lens left. MC-14 right.


MC-14 on the left. MC-20 on the right.


Bare lens on the left. MC-20 on the right.

To my eyes, using the TC's result in better image quality than cropping the bare lens.

It's nice to have options!

MEDISN said:

To my eyes, using the TC's result in better image quality than cropping the bare lens.

Click to expand...

Very interesting, thanks for posting this. I agree with your observation, as far as it goes. The subject is not very informative though… It has sharp detail, like in the logo, but not fine detail. I think fur or fabric, something with low-contrast but high-frequency fine detail would be much more illuminating.

The choice of resampling algorithm will also have a big impact on how effectively the bare lens can compete.

Will Rose said:

MEDISN said:

To my eyes, using the TC's result in better image quality than cropping the bare lens.

Click to expand...

Very interesting, thanks for posting this. I agree with your observation, as far as it goes. The subject is not very informative though… It has sharp detail, like in the logo, but not fine detail. I think fur or fabric, something with low-contrast but high-frequency fine detail would be much more illuminating.

The choice of resampling algorithm will also have a big impact on how effectively the bare lens can compete.

Click to expand...

Good point Will. At 50m or more I am shooting motorsports, snowboarding or surfing, none of which are good cases for fine detail! A bird at that distance would be too small to even press the shutter button with this lens.

I do have examples with some low contrast weathered wood grain at this distance. Focus was on the spine of the letter C.




Bare lens on the left. MC-14 on the right




MC-14 on the left. MC-20 on the right




Bare lens on the left. MC-20 on the right.

The wood grain is easier to follow on the letters and wall with the TC's, whereas the bare lens has areas where the grain is diffuse/ambiguous. Also the shadow areas under top and bottom of the letter has some noise/artifact, mostly mitigated by the TC.

Even up close (2m) the MC-20 is providing more detail than the bare lens cropped. Focus on the rusty bolt below.




Bare lens on the left. MC-20 on the right.

MEDISN said:

Will Rose said:

MEDISN said:

To my eyes, using the TC's result in better image quality than cropping the bare lens.

Click to expand...

Very interesting, thanks for posting this. I agree with your observation, as far as it goes. The subject is not very informative though… It has sharp detail, like in the logo, but not fine detail. I think fur or fabric, something with low-contrast but high-frequency fine detail would be much more illuminating.

The choice of resampling algorithm will also have a big impact on how effectively the bare lens can compete.

Click to expand...

Good point Will. At 50m or more I am shooting motorsports, snowboarding or surfing, none of which are good cases for fine detail! A bird at that distance would be too small to even press the shutter button with this lens.

I do have examples with some low contrast weathered wood grain at this distance. Focus was on the spine of the letter C.

Bare lens on the left. MC-14 on the right

MC-14 on the left. MC-20 on the right

Bare lens on the left. MC-20 on the right.

The wood grain is easier to follow on the letters and wall with the TC's, whereas the bare lens has areas where the grain is diffuse/ambiguous. Also the shadow areas under top and bottom of the letter has some noise/artifact, mostly mitigated by the TC.

Even up close (2m) the MC-20 is providing more detail than the bare lens cropped. Focus on the rusty bolt below.

Bare lens on the left. MC-20 on the right.

Click to expand...

There have been a fairly large number of posts saying that it depends on the lens and TC. I find both the MC14 and the MC20 better than a crop on both the 300mm f4 and the 50-200 f2.8. Maybe I just have TCs which are good matches to a prime and a zoom, but I am glad to see others who find a similar result indicating that it is not specific to just my lenses and TCs.

--
drj3

MEDISN said:

I do have examples with some low contrast weathered wood grain at this distance. Focus was on the spine of the letter C.

MC-14 on the left. MC-20 on the right

Click to expand...

Agreed that they are outperforming the bare lens. However, this shot is the most interesting to me. I think it indicates an anomaly of some sort.

The MC14 is outresolving the bare lens in these shots, yes, but barely. Say 22MP instead of 20. But in this shot, look at the difference. The MC20 is wildly outresolving the MC14. This can be seen in the center near the screw hole, but also in the corner, in the descender on the S.

This difference is so stark, especially when most people don’t get significant improvements on the MC20, that it makes me wonder if something else is at play here. Did the lighting change, so the angle of the sun is revealing more texture for the MC20, or is it possible you didn’t achieve critical accuracy in focusing the MC14 shot, or could your MC14 itself be soft (or even the MC20 be anomalously sharp)?

Usually people see diminishing returns with the magnification of the extender. A big improvement with the MC14, a much additional smaller improvement with the MC20. That’s not what you have here.

If the resolution is in the lens for the MC20 to magnify, it’s there for the MC14. So with the MC20 doing so well, why isn’t the MC14 also showing significant improvements over the bare lens?

Will Rose said:

MEDISN said:

I do have examples with some low contrast weathered wood grain at this distance. Focus was on the spine of the letter C.

MC-14 on the left. MC-20 on the right

Click to expand...

Agreed that they are outperforming the bare lens. However, this shot is the most interesting to me. I think it indicates an anomaly of some sort.

The MC14 is outresolving the bare lens in these shots, yes, but barely. Say 22MP instead of 20. But in this shot, look at the difference. The MC20 is wildly outresolving the MC14. This can be seen in the center near the screw hole, but also in the corner, in the descender on the S.

This difference is so stark, especially when most people don’t get significant improvements on the MC20, that it makes me wonder if something else is at play here. Did the lighting change, so the angle of the sun is revealing more texture for the MC20, or is it possible you didn’t achieve critical accuracy in focusing the MC14 shot, or could your MC14 itself be soft (or even the MC20 be anomalously sharp)?

Usually people see diminishing returns with the magnification of the extender. A big improvement with the MC14, a much additional smaller improvement with the MC20. That’s not what you have here.

If the resolution is in the lens for the MC20 to magnify, it’s there for the MC14. So with the MC20 doing so well, why isn’t the MC14 also showing significant improvements over the bare lens?

Click to expand...

My MC-20 has always performed better than my MC-14. It's consistent across lenses (300/4, 40-150/2.8, 90/3.5, 150-400/4.5). As you point out, my MC-14 is a little better than cropping, plus it makes subject detect easier when the subject is larger in the frame. The advantage of the MC-14 is it still autofocuses better than the MC-20 which has a noticeable impact on AF speed. It's not bad per se, but when you are accustom to bare lens, it feels slower.

The sun was behind the lifeguard station - this side was all shade. They were taken 53 seconds apart. I took 10 frames each silent shutter. There wasn't enough focus variation between them to choose one over another. Each is representative of the other 9 looking at 400% in LR.

Very interesting: thank you for doing these comparisons.

The weather and light here have been miserable since my 50-200 landed, but I have done some informal tests both handheld and on a tripod of the bare lens and with both converters, and while noting some variation (caused I’m sure mainly by changes in lighting and in how much I’m shivering!), like you I haven’t noticed a consistent story.

In other words, I’ve got no evidence for a significant degradation in IQ for my purposes, so pending further experience I shan’t hold back from carrying and using the MC-20 when conditions and subjects may call for it.

Good news.

Will Rose said:

Will Rose wrote

The MC20 is wildly outresolving the MC14. This can be seen in the center near the screw hole, but also in the corner, in the descender on the S.

Click to expand...

I think you are confusing resolution and optical magnification. The MC20 isn't outresolving the MC14, it simply has more optical magnification, hence you can see smaller details better from a same distance. If you want to compare resolution, you have to increase the distance to the focus target so both images are at the same magnification.

The question is whether the theoretically higher RESOLUTION of the bare lens can compensate for the higher MAGNIFICATION obtained with the TC combos, hence making the TC redundent vs cropping and enlarging. So far the evidence point to higher magnification of the TC combos do bring benefit as the details brought by magnification exceed that of the details lost by reduced resolution.

--
Roger

Regor250 said:

Regor250 said:

Will Rose wrote

The MC20 is wildly outresolving the MC14. This can be seen in the center near the screw hole, but also in the corner, in the descender on the S.

Click to expand...

I think you are confusing resolution and optical magnification. The MC20 isn't outresolving the MC14, it simply has more optical magnification, hence you can see smaller details better from a same distance. If you want to compare resolution, you have to increase the distance to the focus target so both images are at the same magnification.

The question is whether the theoretically higher RESOLUTION of the bare lens can compensate for the higher MAGNIFICATION obtained with the TC combos, hence making the TC redundent vs cropping and enlarging. So far the evidence point to higher magnification of the TC combos do bring benefit as the details brought by magnification exceed that of the details lost by reduced resolution.

Click to expand...

Correct, I assume that most users are really referring to the ability of the TC to provide the poorer, the same, or better details when the lens and the lens with TC are both are used at the same distance.

This is really the important characteristic for deciding on whether or not to use a TC with the specific lens. However, this indicates nothing about the TC+lens resolution when compared to lenses with equivalent focal lengths.

When used at different distances so that the target is the same size in the frame, the bare lens will always provide more detail.

drj3 said:

Regor250 said:

drj3 said:

Will Rose wrote

The MC20 is wildly outresolving the MC14. This can be seen in the center near the screw hole, but also in the corner, in the descender on the S.

Click to expand...

I think you are confusing resolution and optical magnification. The MC20 isn't outresolving the MC14, it simply has more optical magnification, hence you can see smaller details better from a same distance. If you want to compare resolution, you have to increase the distance to the focus target so both images are at the same magnification.

The question is whether the theoretically higher RESOLUTION of the bare lens can compensate for the higher MAGNIFICATION obtained with the TC combos, hence making the TC redundent vs cropping and enlarging. So far the evidence point to higher magnification of the TC combos do bring benefit as the details brought by magnification exceed that of the details lost by reduced resolution.

Click to expand...

Correct, I assume that most users are really referring to the ability of the TC to provide the poorer, the same, or better details when the lens and the lens with TC are both are used at the same distance.

This is really the important characteristic for deciding on whether or not to use a TC with the specific lens. However, this indicates nothing about the TC+lens resolution when compared to lenses with equivalent focal lengths.

When used at different distances so that the target is the same size in the frame, the bare lens will always provide more detail.

Click to expand...

Indeed. The obvious benefit from the TC combo is to get better image quality in the 200-400mm range than simply cropping. An interesting test would be to compare, from a same distance, 200mm bare lens to 100mm + TC20 to see the impact on the 100-200mm range. Arguably, only then could you truely demonstrate the impact on optical quality. My assumption would be that in the range covered by the bare lens, the TC will comparatively degrade IQ, so the use of the TC is only supported at total focal range above 200mm. Similarly I like to see similar comparative tests at 250mm, 300mm and 350mm to see if there is a threshold within the 200-400mm range where cropping is actually as good or better.

--
Roger

drmarkf said:

Very interesting: thank you for doing these comparisons.

The weather and light here have been miserable since my 50-200 landed, but I have done some informal tests both handheld and on a tripod of the bare lens and with both converters, and while noting some variation (caused I’m sure mainly by changes in lighting and in how much I’m shivering!), like you I haven’t noticed a consistent story.

In other words, I’ve got no evidence for a significant degradation in IQ for my purposes, so pending further experience I shan’t hold back from carrying and using the MC-20 when conditions and subjects may call for it.

Good news.

Click to expand...

Congrats! You're going to like working with it. I am in the same boat. I think it is pretty good with the MC-20. That gives a full frame equivalent working range of 100mm to 800mm in one lens + a TC with great stabilization and close focus ability. When portability is crucial I might choose it over the 150-400.

























I would be curious to see how it stands up to the OM 100-400 at 400mm, which is smaller collapsed. I don't have that lens to compare with. I used to have the PL 100-400 II but was not impressed with its performance at 400mm.

Regor250 said:

Regor250 said:

Will Rose wrote

The MC20 is wildly outresolving the MC14. This can be seen in the center near the screw hole, but also in the corner, in the descender on the S.

Click to expand...

I think you are confusing resolution and optical magnification. The MC20 isn't outresolving the MC14, it simply has more optical magnification, hence you can see smaller details better from a same distance.

Click to expand...

No, I'm not. If the TCs were both perfect magnifiers, this would be true: but they are not. TCs cannot reveal details that are not coming out of the bare lens, but they can obscure them.

The MC14 is blurring some details that the MC20 is not, details that are big enough to be seen. They’re not just “smaller” in the MC14 image, they’re effectively absent because of blur and lack of micro contrast. The MC20 is showing those details clearly.

In this case, the MC20 is outresolving the somewhat-soft MC14. It may not be the case with other TCs, but it is with this one.

drj3 said:

Regor250 said:

drj3 said:

Will Rose wrote

The MC20 is wildly outresolving the MC14. This can be seen in the center near the screw hole, but also in the corner, in the descender on the S.

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I think you are confusing resolution and optical magnification. The MC20 isn't outresolving the MC14, it simply has more optical magnification, hence you can see smaller details better from a same distance. If you want to compare resolution, you have to increase the distance to the focus target so both images are at the same magnification.

The question is whether the theoretically higher RESOLUTION of the bare lens can compensate for the higher MAGNIFICATION obtained with the TC combos, hence making the TC redundent vs cropping and enlarging. So far the evidence point to higher magnification of the TC combos do bring benefit as the details brought by magnification exceed that of the details lost by reduced resolution.

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Correct, I assume that most users are really referring to the ability of the TC to provide the poorer, the same, or better details when the lens and the lens with TC are both are used at the same distance.

This is really the important characteristic for deciding on whether or not to use a TC with the specific lens. However, this indicates nothing about the TC+lens resolution when compared to lenses with equivalent focal lengths.

When used at different distances so that the target is the same size in the frame, the bare lens will always provide more detail.

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I agree with what you said here, except perhaps for the initial “correct” which depends on what statement you were affirming.

Any optical system has an upper limit on resolution, set by all the elements in the system. For any TC to provide benefit, the main lens must have a resolution higher than the sensor. A TC cannot improve the resolution of the main lens, but it can reduce it. If one TC lowers the system resolution limit more than another, then one TC can outresolve another. The teleconverters used in this test are not ideal (perfect) magnifiers.

If an ideal perfect magnifier were created, such a TC would, strictly speaking, outresolve the lens it is mounted on individually. But as a system it cannot; it cannot deliver to the sensor detail that is not coming out of the lens in the first place.

But that’s not what’s happening here. One of these TCs is softer than the other, and I was comparing the TCs to each other. Lens+TC cannot outresolve Lens, but Lens+TC(A) can outresolve Lens+TC(B).

Resolution of this equipment is obviously really important, but the other vital practical issue in real life use in lower-light wildlife and sports shooting (of which I do a lot) is the effects that adding teleconverters have on acquisition and maintenance of critical focus.

This is doubtless down to the effect on maximum aperture: adding my MC-14 to the 300 f4 has a barely-detectable effect on resolution and focusing, but the MC-20 has a bigger impact.

I sold my OMS 100-400 mkii before the 50-200 arrived so I can’t test the two together, but a big stimulus towards my replacing this with the new lens was the regular frustration with acquiring focus in lower light at the beginning and end of the day. Again this is presumably a max aperture issue. In August in South Africa this outweighed for me the pleasure in having seamless zoom from 200 - 800mm equivalent: early safari light, in particular, can be magical, but so is instant focus.

From my experience with the 40-150 2.8, it’ll be well worth the minor irritation in occasionally swapping a converter in or out: having the extra 100mm at f2.8 will literally be golden at 5.30 am!