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Minolta 24mm f2.8 vs Leica R 24mm f2.8
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PostPosted: Sun Feb 18, 2018 10:51 pm    Post subject: Reply with quote
There are only slight cosmetic differences between your MD I W and my MC W .


PostPosted: Mon Feb 19, 2018 3:06 pm    Post subject: Reply with quote
MC-X, MD-I and early MD-II were the same elements/groups, size and weigth. Late MD-II and MD-III were both different from earlier ones and from one another.


PostPosted: Mon Feb 19, 2018 3:25 pm    Post subject: Reply with quote
michelb wrote:
MC-X, MD-I and early MD-II were the same elements/groups, size and weigth. Late MD-II and MD-III were both different from earlier ones and from one another.


Tabernacle! Quasiment les mêmes lentilles .


PostPosted: Tue Feb 20, 2018 1:47 am    Post subject: Reply with quote
memetph wrote:
michelb wrote:
MC-X, MD-I and early MD-II were the same elements/groups, size and weigth. Late MD-II and MD-III were both different from earlier ones and from one another.


Tabernacle! Quasiment les mêmes lentilles .



On peut dire cela seulement au Québec !


Yes, the lens formula was the same but the coatings changed over time, except for the first MC-X version that weighed 395g instead of he later 275g due to a change in construction of the helicoids from brass to Aluminum. Some say the ones with the SI suffix in the name on the front barrel are the ones with the brass helicoids (and the 395g weight)

Anybody here with a MC W.ROKKOR-X or MC W.ROKKOR (without the SI suffix) that weigh 395g ???? I would like to know the serial number.

See here from left to right MC W.ROKKOR-X SI (395g), MC W.ROKKOR-X (275g), MC W.ROKKOR (275g), MD W.ROKKOR-X ( 275g MD-I), MD W.ROKKOR-X (215g MD-II), MD 24mm (200g MD-III)


PostPosted: Tue Feb 20, 2018 8:21 pm    Post subject: Reply with quote
TrueLoveOne wrote:
papasito wrote:


They have different rendering, and this is the reality.


Minolta changed the barrel construction a few times, not the element's size. That would make it a completely different calculation if you ask me.
Any differences in rendering is due to the fact that they improved on coatings over the years.


I dissasembly both lenses by miself

The MD (9/7) elements were smaller than the MC ones.

I don't know why nobody beleve that

And more, nobody of all that said It's no real, have dissamble the lens.

All the people say what they say without the experience of had done that.


PostPosted: Tue Feb 20, 2018 11:19 pm    Post subject: Reply with quote
papasito wrote:



I don't know why nobody beleve that



I believe you and here's why, 'there is no substitute for hands on'. I was a technician in electronics for years and the one thing I truly learned was through repetition my mind never plays tricks on me, however I can't begin to tell you how many times I've read something and confused/merged information or simply forgot details, of which never happens with hands on experience ...ever, well for those of us that expect to eat every night and sleep in a warm bed that is, so I agree the view from the repetitive assembly and disassembly person (hands on) is often the most reliable information of all. And I highly respect it, (very interesting thread I'm learning from, much appreciated)


PostPosted: Wed Feb 21, 2018 8:28 am    Post subject: Reply with quote
[quote="papasito"][quote="TrueLoveOne"][quote="papasito"]


I dissasembly both lenses by miself

The MD (9/7) elements were smaller than the MC ones.

I don't know why nobody beleve that

And more, nobody of all that said It's no real, have dissamble the lens.

All the people say what they say without the experience of had done that.[/quote]

One is of the most difficult challenges in life is to let go and stop believing what you "know" when faced with evidence to the contrary.


PostPosted: Wed Feb 21, 2018 8:39 am    Post subject: Reply with quote
Papasito
http://minolta.eazypix.de/lenses/index.html
Look at this table.
First MC 24 mm SI weighs 395 grams 1973
Then MC, MD I, MD II weigh 275 grams 1975, 77, 78
Then MD II new version weighs 215 grams 1978
all above 9/7
then MD III 8/8 weighs 200g 2001
So, differences more than just MC or MD. Different MCs and different MDs and some MC and MD being the same...
In your post, you are not precise enough about which model you disassembled and people may have different meaning when they refer to MC or MD. This may explain.


PostPosted: Thu Feb 22, 2018 4:38 pm    Post subject: Reply with quote
Antoine wrote:
Papasito

In your post, you are not precise enough about which model you disassembled and people may have different meaning when they refer to MC or MD. This may explain.


You are right, Antoine.

The MC was the first.

The MD was the last MD II.

I apologize.


PostPosted: Thu May 06, 2021 11:38 pm    Post subject: Reply with quote
papasito wrote:
The Minolta MC and MD I versions of the 24/2,8 are different lenses

They have similar scheme but:

The MDI have smaller lenses than the MC:

The same formula, yes. But the elements are not interchangeable between them.

The MDI's elements are smaller than the MC's ones.

So the lenses aren't the same.

They have different rendering, and this is the reality.


I am interested in your appreciation of image quality between the older heavier versions and the last 9/7 215 gr version.


PostPosted: Fri May 07, 2021 10:14 pm    Post subject: Reply with quote
lumens pixel wrote:
papasito wrote:
The Minolta MC and MD I versions of the 24/2,8 are different lenses

They have similar scheme but:

The MDI have smaller lenses than the MC:

The same formula, yes. But the elements are not interchangeable between them.

The MDI's elements are smaller than the MC's ones.

So the lenses aren't the same.

They have different rendering, and this is the reality.


I am interested in your appreciation of image quality between the older heavier versions and the last 9/7 215 gr version.

I can check tomorrow since I have all relevant versions (MC-X [395g], MC-X [275g], MD-II [275g], MD-II [215g], MD-III [200g]).

S


PostPosted: Sat May 08, 2021 1:27 am    Post subject: Reply with quote
Fantastic.


PostPosted: Sun May 09, 2021 7:45 pm    Post subject: Reply with quote
papasito wrote:
The Minolta MC and MD I versions of the 24/2,8 are different lenses
They have similar scheme but:
The MDI have smaller lenses than the MC:
The same formula, yes. But the elements are not interchangeable between them.
The MDI's elements are smaller than the MC's ones.
So the lenses aren't the same.
They have different rendering, and this is the reality.



Antoine wrote:
Papasito,
This does not look right. From the tables, it seems that MC MD I and the first MD II are the same and that Minolta issued a 2nd MD II much lighter (215 versus 275 g) before launching the MD III 8/8. It remains to be seen whether the 9/7 lenses are not all the same with the latest MD II version being just a mechanically optimised version.
Artaphot does not differentiate between the various 9/7.


Over the weekend I have checked the five Minolta 2.8/24mm lenses I own (with SR bayonet), along with about ten other vintage 24mm and 25mm lenses.

* Minolta Rokkor-SI MC-X 2.8/24mm ([9/7], 395g, Dennis Lohmann Nr 26)
* Minolta Rokkor MC-X 2.8/24mm ([9/7], 275g, Dennis Lohmann Nr 27)
* Minolta Rokkor MD-II 2.8/24mm ([9/7], 275g, Dennis Lohmann Nr 29, absolutely identical to the MD-I version apart from its MD-II-style description on its front ring)
* Minolta Rokkor MD-II 2.8/24mm ([9/7], 215g, Dennis Lohmann Nr 30)
* Minolta Rokkor MD-III 2.8/24mm ([8/8,] 200g, Dennis Lohmann Nr 31)

Here a few comments:

1) Lenses Nr 26, 27, 29, and 30 have identical reflections, indicating an identical or extremely similar optical construction
2) Lens Nr 26 has a slightly yellowish color cast, all others have no such color cast
3) Lens Nr 26 performs slightly different than the lenses 27, 28, and 30
4) Lenses 27, 28, and 30 perform identical
5) Lens 31 is the smallest, lightest and best of the bunch
6) Out of about ten other vintage lenses in the 24mm range, only the Nikkor AiS 2.8/24mm and the Zeiss Distagon CY 2.8/25 have a similar performance as the Minolta MD-III 2.8/24mm

Images will follow later on artaphot.

S


PostPosted: Sun May 09, 2021 8:33 pm    Post subject: Reply with quote
Great piece of information, as always.


PostPosted: Sun May 09, 2021 8:43 pm    Post subject: Reply with quote
Excellent! Thanks!


PostPosted: Thu Dec 30, 2021 4:47 am    Post subject: Reply with quote
How ridiculous it sounds when someone blankets a lens as best...

What that proves to me is some people hype things in order to increase their own sales margins

A belief held for years and years, suddenly is upended without any new revelation attached to upend what was always held?

Film, Digital FF, Crop, M4/3, video ...indoor/outdoor/natural light/flash/ yet someone says better as in best without providing a single clue as to what?

Better than my Roomba dusting wood floors?

Say best, but if you do please give us the courtesy in providing how you came to that conclusion so we can repeat your study ourselves?

Until someone can then your findings are meaningless, proof is not in what you discover, it's in our ability to discover it exactly as you have..... if we can find what you did... matters most

and words are mutterings only until then


PostPosted: Thu Dec 30, 2021 9:00 am    Post subject: Reply with quote
Your post is unfair (disjointed?) as you did not care to go to his website and see the tests Steve has carried out.
His conclusions are valid for this test, nothing more, nothing less...


PostPosted: Thu Dec 30, 2021 10:57 am    Post subject: Reply with quote
wildlight images wrote:
papasito wrote:



I don't know why nobody beleve that



I believe you and here's why, 'there is no substitute for hands on'. I was a technician in electronics for years and the one thing I truly learned was through repetition my mind never plays tricks on me, however I can't begin to tell you how many times I've read something and confused/merged information or simply forgot details, of which never happens with hands on experience ...ever, well for those of us that expect to eat every night and sleep in a warm bed that is, so I agree the view from the repetitive assembly and disassembly person (hands on) is often the most reliable information of all. And I highly respect it, (very interesting thread I'm learning from, much appreciated)


I would also believe this. I've personally only taken an MC 24mm apart, so can't confirm, but there have been several occasions with their Rokkor lenses where Minolta did not change the optical design (i.e. same lens curvatures, thicknesses, refractive indices etc.) between MC / MD-I variants, but they did change e.g. the lens mounting and associated chamfering of the lens edges. Minor adjustments to the lenses circumference would not surprise me at all. It wouldn't be much, but enough to make the lenses not interchangeable. Indeed we all know that whilst some lenses did not change formulation in terms of no. lenses & groups, they were recalculated, e.g. the earlier vs the later MC 58mm f/1.2 where the radioactive Thorium element was replaced by a different one of non-radioactive composition, which almost certainly would have required changes to the curvature & thickness as well.

There is something to bear in mind when comparing performance of MC / MD variants of any of Minolta's floating focus Rokkor designs (MC/MD 17mm f/4, MD 20mm f/2.8, MC 21mm f/2.8, MC/MD 24mm f/2.8, MC/MD 24mm f/2.8 VFC, MC/MD 28mm f/2, MC/MD 35mm f/2.8 SHIFT-CA) or indeed when comparing two specimen of the same lens in that series. During its life some of those lenses may have been serviced by amateurs or indeed even professional camera service centres that weren't aware of, or couldn't be bothered with, the procedure & tools required to temporarily lock the float space down whilst fine-adjusting the collimation. This will have a noticeable detrimental impact on field curvature and corner sharpness.

A few disassembly/reassembly "tutorials" of these Rokkors with floating focus exist on YouTube where this required step during collimation is omitted. Some even pay no notice at all to the fact that the locking nuts of the floating group allow for some adjustment to get the float-space correct to an accuracy of around 0.02mm, they just put them back in and tighten up the scews, leaving the field curvature totally messed-up... Sad

Servicing these lenses absolutely requires Minolta's float space set tool and auxiliary locking tool. Alternatively (as Minoltas servicing tools will be nigh-impossible to find now) it is possible to use a 20-micron precision Vernier-depth-gauge or Micrometer-depth-gauge plus a lot of patience. This requires iterative and alternating adjustment of both float space and collimation until you get adequate convergence of dimensional positioning of the float space. This procedure works by convergence because for a given degree of turning of the focus ring, the change in internal float space is less than the change in back focus of the lens. Of course this procedure only works if you know what the float space should be exactly, which can be measured on a known good lens of same generation, or measure before disassembly if the lens to be serviced is known to have good field curvature.


PostPosted: Thu Dec 30, 2021 2:19 pm    Post subject: Reply with quote
How does the sigma super wide 24/2.8 compare to the MDiii and Nikkor ai-s 24/2.8?


PostPosted: Thu Dec 30, 2021 5:46 pm    Post subject: Reply with quote
RokkorDoctor wrote:
wildlight images wrote:
papasito wrote:



I don't know why nobody beleve that



I believe you and here's why, 'there is no substitute for hands on'. I was a technician in electronics for years and the one thing I truly learned was through repetition my mind never plays tricks on me, however I can't begin to tell you how many times I've read something and confused/merged information or simply forgot details, of which never happens with hands on experience ...ever, well for those of us that expect to eat every night and sleep in a warm bed that is, so I agree the view from the repetitive assembly and disassembly person (hands on) is often the most reliable information of all. And I highly respect it, (very interesting thread I'm learning from, much appreciated)


I would also believe this. I've personally only taken an MC 24mm apart, so can't confirm, but there have been several occasions with their Rokkor lenses where Minolta did not change the optical design (i.e. same lens curvatures, thicknesses, refractive indices etc.) between MC / MD-I variants, but they did change e.g. the lens mounting and associated chamfering of the lens edges. Minor adjustments to the lenses circumference would not surprise me at all. It wouldn't be much, but enough to make the lenses not interchangeable. Indeed we all know that whilst some lenses did not change formulation in terms of no. lenses & groups, they were recalculated, e.g. the earlier vs the later MC 58mm f/1.2 where the radioactive Thorium element was replaced by a different one of non-radioactive composition, which almost certainly would have required changes to the curvature & thickness as well.

There is something to bear in mind when comparing performance of MC / MD variants of any of Minolta's floating focus Rokkor designs (MC/MD 17mm f/4, MD 20mm f/2.8, MC 21mm f/2.8, MC/MD 24mm f/2.8, MC/MD 24mm f/2.8 VFC, MC/MD 28mm f/2, MC/MD 35mm f/2.8 SHIFT-CA) or indeed when comparing two specimen of the same lens in that series. During its life some of those lenses may have been serviced by amateurs or indeed even professional camera service centres that weren't aware of, or couldn't be bothered with, the procedure & tools required to temporarily lock the float space down whilst fine-adjusting the collimation. This will have a noticeable detrimental impact on field curvature and corner sharpness.

A few disassembly/reassembly "tutorials" of these Rokkors with floating focus exist on YouTube where this required step during collimation is omitted. Some even pay no notice at all to the fact that the locking nuts of the floating group allow for some adjustment to get the float-space correct to an accuracy of around 0.02mm, they just put them back in and tighten up the scews, leaving the field curvature totally messed-up... Sad

Servicing these lenses absolutely requires Minolta's float space set tool and auxiliary locking tool. Alternatively (as Minoltas servicing tools will be nigh-impossible to find now) it is possible to use a 20-micron precision Vernier-depth-gauge or Micrometer-depth-gauge plus a lot of patience. This requires iterative and alternating adjustment of both float space and collimation until you get adequate convergence of dimensional positioning of the float space. This procedure works by convergence because for a given degree of turning of the focus ring, the change in internal float space is less than the change in back focus of the lens. Of course this procedure only works if you know what the float space should be exactly, which can be measured on a known good lens of same generation, or measure before disassembly if the lens to be serviced is known to have good field curvature.


Eek! This makes my head hurt RokDoc., but great to know so I don't ruin a perfectly good lens just to attempt to get out a tiny dust spec.

Maybe unlikely, because as I age and my fingers do more what they want than what I say to do, I take on opening lenses less and less frequently. Now I can afford all the lens tools I want, but at the same time I can hardly get my fingers to do what I tell them to do Sad

Thank you for sharing your wisdom. I don't yet have a 24mm Rokkor, but will get one when I see a good copy at a fair price. You just saved it from the dustbin!

Thank you!


PostPosted: Thu Dec 30, 2021 6:16 pm    Post subject: Reply with quote
Teemō wrote:
I've heard that the Olympus OM 24/2.8 is better than most competing lenses - it's certainly the same price or cheaper as the Minolta and I believe more compact. They also made an F2 variant. Since the FFD is much longer on the OM system, you can adapt to EF with a glassless adapter and maintain infinity focus!


OM is a very good lens. The best? For me the MC version.


PostPosted: Thu Dec 30, 2021 9:15 pm    Post subject: Reply with quote
RokkorDoctor wrote:

... During its life some of those lenses may have been serviced by amateurs or indeed even professional camera service centres that weren't aware of, or couldn't be bothered with, the procedure & tools required to temporarily lock the float space down whilst fine-adjusting the collimation. This will have a noticeable detrimental impact on field curvature and corner sharpness.

A few disassembly/reassembly "tutorials" of these Rokkors with floating focus exist on YouTube where this required step during collimation is omitted. Some even pay no notice at all to the fact that the locking nuts of the floating group allow for some adjustment to get the float-space correct to an accuracy of around 0.02mm, they just put them back in and tighten up the scews, leaving the field curvature totally messed-up... Sad

Servicing these lenses absolutely requires Minolta's float space set tool and auxiliary locking tool.
...


Interesting - I didn't know this.

That said, the only lens with floating elements I have ever dis- and reassembled was a Minolta MD-III 2.8/20mm which obviously had been immersed in water for some time. No real damage, apart from some corroded screws. This was many moons ago, and I don't remember exactly how I did it. If I remember correctly, there was a second male/female thread for the floating element, and re-mounting it was only possible in discreet steps - either field curvature was positive, neutral (=correct) or negative, depending on which "slot" you took while re-assembling. I can't remember having seen a mechanism / device to continuously adjust the floating focusing, but my memory may well be wrong.

However, even without correct tools, the re-assembled MD 2.8/20mm is better than the previous MC 2.8/21mm and certainly much better than several other vintage superwides I own.

S

Last edited by stevemark on Mon Nov 20, 2023 1:23 pm; edited 1 time in total


PostPosted: Fri Dec 31, 2021 12:21 am    Post subject: Reply with quote
stevemark wrote:


Interesting - I didn't know this.
If I remember correctly, there was a second male/female thread for the floatring element, and re-mounting it was only possible in discreet steps - either field curvature was positive, neutral (=correct) or negative, depending on which "slot" you took while re-assembling. I can't remember having seen a mechanism / device to continuously adjust the floating focusing, but my memory may well be wrong.

However, even without correct tools, the re-assembled MD 2.8/20mm is better than the previous MC 2.8/21mm and certainly much better than several other vintage superwides I own.

S


I agree that the MD 2.8/20mm was an improvement on its MC 2.8/21mm predecessor.

Most of Minolta's floating focus Rokkors I have seen inside have the following set-up (but the MC 21mm f/2.8 is quite different, and the later MDIII 24mm f/2.8 is likely different as well, can't recall from memory):

- front cell is mounted on the rotating front section of the focus helicoid (hence the rotating front element)
- rear cell (floating cell) is mounted in a floating cylinder/sleeve, keyed to the main barrel/mount of the lens (hence non-rotating), but otherwise free to move back and forth along the lens' main optical axis
- the rotating front section of the focus helicoid has two identical angled slots milled in it, that engage two cams on the floating cylinder/sleeve
- this arrangement therefore determines the positioning of the rear floating cell/cylinder relative to the front cell ("float space") much like lens groups are positioned in zoom lenses
- the two cams on the floating cylinder are held in place with two rectangular nuts inside that cylinder, each of which is provided with one fixed screw hole (used for the float space retention tool) and three other usable screw holes for the cams. Normally the middle hole of those three is used for the cams, but the other two are provided in case a major rotational adjustment of the focus helicoid is required for collimation, to prevent the cams then hitting the end stops on the milled angled slots
- the (unthreaded) holes for the cam screws in the floating cylinder have been machined significantly oversize, such that the positioning of the floating group cams can be dictated by the float space sleeve fitting tool, rather than by the screw holes leading to the nuts

Broadly speaking, the assembly & adjustment procedure for these lenses is then as follows (note this is my summary from the relevant instructions in Minoltas official service manuals):

- after assembly of the helicoid assembly, the length of the helicoid assembly needs to be set to a prescribed measure (28.60mm in case of the MC-X 24mm f/2.8 )
- the floating cylinder/sleeve is then inserted into the helicoid assembly, and the exact positioning is achieved using Minolta's sleeve fitting tool. This is a stepped tool that dictates how far the front rim of the floating cylinder/sleeve is recessed into the helicoid block. Unfortunately the service manual does not indicate this critical dimension for those not in possession of the sleeve fitting tool (The floating cylinder is my own terminology, it was not available as a spare part by minolta "NO SUPPLY" hence no name given by Minolta in their service manual, albeit that they seem to refer to is as "sleeve")
- the rectangular nuts are fixed inside the floating cylinder on their fixed hole by means of a float space retention tool, which is fitted from outside the helicoid block but has a pin protruding into a slot milled in the floating cylinder. This will allow the rotating front section of the focus helicoid to rotate around the floating cylinder, whilst maintaining a constant infinity focus float space (i.e. the floating focus feature is temporarily defeated). Note that the floating focus cams have therefore not yet been fitted at this stage.
- the sleeve fitting tool is removed
- the front and rear cells are fitted and the lens is further assembled almost to completion, but the focus grip is not yet fitted to keep the angled slots for the floating focus accessible.
- the lens in now collimated, with the float space locked at the designed size for flat field curvature at infinity focus
- after collimation, the cams for the floating cylinder are fitted and secured in the centre one of the three holes provided in the internal nuts, and the float space retention tool is removed. The other two holes can be used instead if required to prevent the cams from hitting the end stop of the angled slots if collimation involved an abnormal rotational fine-tuning of the focus helicoid (this should be rare).
- finally the floating focus slots dust shield is fitted, and the focus grip is mounted onto the lens at the infinity position

If collimation is (erroneously) done with the cams locked in place instead of the float space retention tool fitted, then e.g. with a collimation adjustment as small as 5m -> infinity (only a couple of degrees or so on the helicoid), infinity focus will be achieved with the float space set for correction of field curvature at 5m focus, and corner resolution will suffer.


PostPosted: Fri Oct 28, 2022 4:05 pm    Post subject: Reply with quote
Maybe not the best thread to post this but the information might be of interest.

I own an MDII 24 mm 2,8. Was never impressed. Quite fuzzy starting at the line of thirds, getting somewhat better in the corners. Sharp at the center.

Disappointed after an MDIII 24 2,8 I sold because corners where not interesting.

Both lenses superseded by a Sigma SuperWide 24 2,8.

I recently shimmed again the adapter of my Sony A 7 and this time I hit infinity spot on.

The MDII 24 2,8 shines now. There is a hint of softness in the last corner pixels at around f6,7 but nothing that justifies to close more the aperture and start facing diffraction. It is now a very good lens certainly not worse than the Sigma.

I regret having sold the MDIII since I would have liked to compare it on the shimmed adapter but I am already happy with the MDII that has excellent sharpness on 90% of the field. Construction and colors are superb like often with Minolta.

Beware your adapters with floating designs.


PostPosted: Fri Oct 28, 2022 4:38 pm    Post subject: Reply with quote
lumens pixel wrote:
Maybe not the best thread to post this but the information might be of interest.

I own an MDII 24 mm 2,8. Was never impressed. Quite fuzzy starting at the line of thirds, getting somewhat better in the corners. Sharp at the center.

Disappointed after an MDIII 24 2,8 I sold because corners where not interesting.

Both lenses superseded by a Sigma SuperWide 24 2,8.

I recently shimmed again the adapter of my Sony A 7 and this time I hit infinity spot on.

The MDII 24 2,8 shines now. There is a hint of softness in the last corner pixels at around f6,7 but nothing that justifies to close more the aperture and start facing diffraction. It is now a very good lens certainly not worse than the Sigma.

I regret having sold the MDIII since I would have liked to compare it on the shimmed adapter but I am already happy with the MDII that has excellent sharpness on 90% of the field. Construction and colors are superb like often with Minolta.

Beware your adapters with floating designs.


Indeed, having both the lens correctly collimated and the adapter adjusted for the exact register adaptation are critical with both floating design lenses as well as parfocal zoom lenses. Allowed tolerances here are in the order of only 20 microns (0.02mm), with a little more leeway for slower lenses.

If the camera/adapter/lens combination is not set up/collimated/adjusted to that level of tolerance, unfortunately it won't be possible to make any meaningful comments about corner sharpness / field flatness of a floating design lens from the empirical results.

This gets more critical with reducing focal length. E.g. the Minolta Rokkor 17mm/4 is highly critical in this respect; its corners are pretty good if the whole setup has been properly collimated/adjusted, but can be quite soft if something is off in the calibration. If the lens has been DIY-collimated without taking precautions as to maintaining the correct float-space for infinity focus, the lens can be a poor performer regardless of the correct register adaptation of the adapter used.
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