[wim]

You again write a lot without being correct in any point. 

 

Calibration does not touch on telling the lens where to stop to achieve focus. It calibrates the steps a lens makes. The AF system can see when something is in focus, but does not check the end and leaves that to a rightly calibrated lens, for speed purposes (the camera manufacturers do not want a hunting game at the end, where focus is never really achieved).

 

The flange distance is only of interest for reaching infinity and determined MFD. It has no bearing what so ever on AF or AF accuracy. Again, see extension tubes (lenses work just fine with them, despite what your typing suggests).

You have no clue on how PD AF actually functions on DSLRs...  :ph34r:

 

The noise banding the 5D mkII gives is very widely known. The 5D mk II in my opinion is a nice tool, but in sensor output the 6D has passed it by some margin.

Funny on how you always interpret things the way you want to, how you insist on others proving things, and not proving anything yourself.


Correct flange distance is one thing, and only part of shimming. AF accuracy is influenced by correct position of lens relative to sensor in its 3D position on the camera.


Of course do extension tubes work with lenses, I have been using them for only 40+ years. Read again what I said.


As to having clues about anything, I reckon I have forgotten more than you have ever learned, my dear.


As to noise banding, have you ever actually experienced it? I guess not. Yes, I have read about it, I own a 5D II, and you know what? As already mentioned, never experienced it.


And yes, the 6D is a nice camera, with newer sensor technology, never denied that. For me not an upgrade, however, for the type of shooting I do.


Anyway, wasted too much time here already. I do not need to prove anything, and neither do I feel the inclination. Just trying to help people.


Regards, W.

[wim]

@ Wim:  You are hardly the one I would challenge when it comes to macro work!  Not if you run around with the 65mm MPE!

 

I did forget to mention in the above comment that you are indeed correct, many lenses do no focus correctly with tubes attached.  What makes this tolerable is the fact that your higher magnification at least allows you to see more details, if you have good lighting.

 

The same thing could be expected with anything changing depths of field, such as close-up lenses.  Which is why (Just guessing) close-up lens work better further away from the subject.  Because the size of the focus steps will be off, hence Canon's advice, that AF even using their doublet closeup lenses is not recommended.  Now, it comes down to scale.  Is there enough difference to make a difference.

 

Let me throw in one example why I think the answer is maybe yes.  Even decent quality adapters from Pentax, Nikon, M42, and Tamron Adaptall-2 to EOS.  Often loose infinity focus.  This is regardless of the quality of the lens in question.  It can only be the adapter, and the adapter is not off by very much!  One that looks identical to the eye, might give perfect results.  So, it just makes me wonder, that's all. 

 

Of course I don't need to understand perfectly how the system works.  But one speculates on one's hobby.  It's human nature.

I actually literally run around with the MP-E, often with an extender added, with a triple ring flash, and a bracket so I can hold it with both hands. Works well, actually.


I always recommend extension tubes for shorter lenses, and close-up lenses for longer ones, as tubes have a greater effect on shorter lenses and close-up lenses on longer ones.


AF with tubes or close-up lenses is not recommended because at close distances the distance to the rear nodal point of a lens increases drastically, and is often larger than the change in distance to the front nodal point when focusing. This also the reason why one often sets a magnification and then moves the entire setup, and also why macro focusing rails are popular (no need to move the camera and tripod continuously).


Close-up lenses effectively shorten the FL of a lens, and with the nodal point at the back staying in a position for a longer FL this results in a larger magnification. This is the simplified version .

I have always used a Canon 500D close-up lens (the doublet, anachromat), with my 100-400L, old and new. On the old one by zooming from 100 to 400 you went from a 1:4 magnification to 1:1, while keeping a good distance from the subject. Since the Mk II lens focuses a lot closer, I expect even better results magnification wise, but I haven't tried the limits yet.


With the doublet you could try AF, as long as you stay within the focusing range, but you're talking cms here, so not easy. Best is always to set a magnification and move the entire setup, camera and lens, for focusing. You still need to adjust anyway, for optimal sharpness.


Cheap adapters, and even more expensive ones, have not necessarily the correct mount tolerances, if at all possible of course, and in addition have only very limited space or depth available for allowing infinity focus, while fitting all the mechanisms and/or electronics required as wel, and maintaining a stable mount.


I have recently given up completely on those for Canon bodies as they were not satisfactory to me. IOW, all my non-Canon and non-MFT lenses have left the house now , except a few high quality enlarging lenses (for macro work ).


I only adapt lenses now for systems with much shorter flange distances, such as EF lenses adapted for MFT , and only with first rate adapters. That works well enough for me . I have also given up on old analog lenses - they just don't cut it on digital, optically, and I am not interested in any "special effects" they may or may not provide .


Kind regards, Wim

[Brightcolours]

Funny on how you always interpret things the way you want to, how you insist on others proving things, and not proving anything yourself.


Correct flange distance is one thing, and only part of shimming. AF accuracy is influenced by correct position of lens relative to sensor in its 3D position on the camera.


Of course do extension tubes work with lenses, I have been using them for only 40+ years. Read again what I said.


As to having clues about anything, I reckon I have forgotten more than you have ever learned, my dear.


As to noise banding, have you ever actually experienced it? I guess not. Yes, I have read about it, I own a 5D II, and you know what? As already mentioned, never experienced it.


And yes, the 6D is a nice camera, with newer sensor technology, never denied that. For me not an upgrade, however, for the type of shooting I do.


Anyway, wasted too much time here already. I do not need to prove anything, and neither do I feel the inclination. Just trying to help people.


Regards, W.

Funny how you always type with fake authority about things you do not know or understand.

 

You can keep on stating that "shimming" for the correct flange distance does impact AF, but that keeps on being categorical nonsense.

 

Like I pointed out, extension tubes work fine with the AF system. They would not if a percentage of a mm even would impact the AF accuracy, as you keep on implying. So, I think it is about time you gave that nonsense point a rest?

 

About you having forgotten a lot... yes, it does appear so.  

 

About the 6D, just stated some facts. Did not state it is the best camera, did not state you have to like it or want one, or any one else for that matter. Just stated some facts as reaction to your writings.  :lol:

 

Don't try to help people with disinformation (about shimming of lenses being used to calibrate lenses to the AF system, about CA being about blue light in particular, about Nikon only having a higher DR because of NR which loses detail, about ISO being defined with light hitting a square area unit, and other wrong understandings).

 

It is fine to help, it also is fine to understand when you have it wrong and not to deride me whenever I explain things. And no, I do not pretend to know everything. I usually do not write about things I have no clue about, and when I have misuderstood something, I acknowledge it and give it a rest.

 

So, again, no, no shims are used to get accurate AF. We know a lens' position is not that important for AF to work, even without having to delve deeper into the actual nitty gritty of the workings of the AF system, simply by observing that AF keeps on working fine with extension tubes.

[toni-a]

As the local proverb says : دق المي مي

Now I understand a proverb my other used to tell me back in adolescence years:

عنزة ولو طارت

[Arthur Macmillan]

"I have recently given up completely on those for Canon bodies as they were not satisfactory to me. IOW, all my non-Canon and non-MFT lenses have left the house now , except a few high quality enlarging lenses (for macro work )."

 

Interesting summation Wim.  And I have to admit I only have an intuitive grasp of why the tubes defeat AF to a large extent.  I agree, tubes for shorter focal lenght, and Diopters for longer lengths, and yes they do seem to give the best of both worlds as far as image brightness and AF within their foreshortened focal distance range.  Also, someone, perhaps you(?) mentioned an interesting fact that teleconverters often are more useful with macro lenses then at telephoto distances.

 

And...I'm almost prepared to guess that your junking of analogue lenses.  Sort of a Wimsical term since really, all lenses are analogue), but I get your meaning, Junking them just because they are confusing more than not capable.

 

Tubes shorten the distance between lens and object.  Yet Canon's life size converter changes its 50/2.5 1:2 macro to 1:1 macro, and actually increases the MFD, giving you more working room

 

My guess is that you just want to make your life simpler.  I don't even believe you believe your modern lenses are more than just convenient to use.  Lots of old lenses render perfection as we know it, even today.  Just not always as easily.

 

Pick up a couple lenses like the old Tamrons SP 500 F/8 mirror and you can sit somewhere and catch great candid, and bird in flight photos. 

 

What I'm getting at is if you are just junking some high end legacy glass...sent it to me!  But is has to be clean and with a long silky well damped and wide focus ring!  I still like taking the MF lenses out for fun.

 

Last time I checked Canon was not offering a 15mm 1:1 macro.  Surely you can make an exception to your rule, and get this one!

And yet.  Now I have Canon APS-c, Canon full frame.  And I want MFT as well.  So I must get rid of my beloved old lenses, to make was for efficent systems.  You are really pointing the way! Wim!

[wim]

As the local proverb says : دق المي مي

Now I understand a proverb my other used to tell me back in adolescence years:

عنزة ولو طارت

 



 

"something may not be as valuable as it first appears

and

"a goat, even if it flies"

 

The question is: to whom are you replying with these quotes?

 

Kind regards, Wim

[wim]

"I have recently given up completely on those for Canon bodies as they were not satisfactory to me. IOW, all my non-Canon and non-MFT lenses have left the house now, except a few high quality enlarging lenses (for macro work)."

 

a.
Interesting summation Wim.  And I have to admit I only have an intuitive grasp of why the tubes defeat AF to a large extent.  I agree, tubes for shorter focal lenght, and Diopters for longer lengths, and yes they do seem to give the best of both worlds as far as image brightness and AF within their foreshortened focal distance range.  Also, someone, perhaps you(?) mentioned an interesting fact that teleconverters often are more useful with macro lenses then at telephoto distances.

 

b.
And...I'm almost prepared to guess that your junking of analogue lenses.  Sort of a Wimsical term since really, all lenses are analogue), but I get your meaning, Junking them just because they are confusing more than not capable.

 

c.
Tubes shorten the distance between lens and object.  Yet Canon's life size converter changes its 50/2.5 1:2 macro to 1:1 macro, and actually increases the MFD, giving you more working room

 

d.
My guess is that you just want to make your life simpler.  I don't even believe you believe your modern lenses are more than just convenient to use.  Lots of old lenses render perfection as we know it, even today.  Just not always as easily.

 

Pick up a couple lenses like the old Tamrons SP 500 F/8 mirror and you can sit somewhere and catch great candid, and bird in flight photos. 

 

e.
What I'm getting at is if you are just junking some high end legacy glass...sent it to me!  But is has to be clean and with a long silky well damped and wide focus ring!  I still like taking the MF lenses out for fun.

 

f.
Last time I checked Canon was not offering a 15mm 1:1 macro.  Surely you can make an exception to your rule, and get this one!

And yet.  Now I have Canon APS-c, Canon full frame.  And I want MFT as well.  So I must get rid of my beloved old lenses, to make was for efficent systems.  You are really pointing the way! Wim!

 

Hi Arthur,

 

Just added some letter annotations to answer more easily .

 

a.
Essentially, very often the extension on the camera side makes that the forward movement of the lens is much larger than the focusing of the lens allows, which means that you just can't focus anymore without moving the entire camera/lens setup. And with close-up lenses, the focusing area falls often well before the normal focusing area/reach, so you also have to move the entire setup.

I can't remember saying anything about teleconverters in this regard, but I certainly do use them for macrophotography, f.e. with the MP-E 65 .

 

b.
No, actually, just not capable enough compared to 30-40 year old newer lenses. F.e., my old SMC Pentax 20 F/4, which I got in 1978 had a reasonably sharp centre, but the corners weren't that great. Not as bad as the Sigma 12-24 EX at 12 mm, mind you, but it cannot hold a candle to my TS-E 17L, not by a very long shot. Even the 17-40 F/4L at 20 mm was better, to be very honest. Add to that that I would need to use an adapter, adding effectively another item which would make the lens potentially less sharp due to potential alignment problems. Furthermore, lenses for film generally were of a simpler design, often predating computing solutions for optical calculations, and hence never were as good as at least some of the modern designs.

 

Do note that I tried, f.e., from a 50 mm POV, a Pentax 50 mm F/1.7, 1.4, Contax Zeis T* 50 F/1.4, Olympus 50 F/1.4 and F/1.8 (I think, could be F/1.7), some old Nikon 50 F/1.4, Canon 50 F/1.8 Mk I, Mk II, 50 F/2.8 Macro, on FF and APS-C cameras, and those and a few more on MFT, (f.e., Canon FD 55 F/1.2) and neither could convice me at all, barring the EF Canons, but even those were not in the same league as my current lenses.

 

All in all, I never used them anymore thereafter. Not as sharp, not as contrasty, not as good in the corners, and requiring at least 2 to 3 stops, sometimes more, to get to an acceptable level of sharpness, contrast and convenience, to me anyway.

 

If I was in for specific effects, I guess I might have kept some, but the truth is it wasn't worth it to me, and adapting them when I needed them was another barrier as well, even though I kept a bunch of them adapted all the time.

 

c.
The 1:1 converter for the Canon 50 Macro is actually just that: a dedicated converter (with glass IOW) plus extension tube combined into one. I had one of those as well . Although I really liked the 50 Macro, apart from the noise it made, the 1:1 converter was not necessarily all that great.

 

d.
Is it about making life simpler? No, I think it was about effectuating the actual status quo. I was never going to use those lenses ever again. Did it hurt to get rid of them? Yes. I made some great photographs with them back in the days .... But what is the use letting them lie around and not using them? If someone else wants them and actually uses them, better for them.... I got really frustrated with them when used with digital cameras - digital shows the shortcomings of these old lenses too well.

 

As to mirror lenses: out of curiosity I have tried them out, but somehow I never really liked the fact that you could not adjust aperture .

I am lucky enough to own a 100-400L II, so I don't really need a mirror lens anyway. Just add a 1.4X extender, and I have a better performing 560 F/8 .

 

e.
Well, I actually brought them to a photo retailer friend of mine - some of these lenses still have real resale value, like the Contax Zeiss 50, the Pentax 20 F/4, the Leitz 60 Macro. He will sell those for me, for a small commission. I don't have the time anyway to do so myself.

 

I could check if the 135mm F/3.5 Pentaxes (from around 1980) are still available if you are interested, or the Pentax 100 F/4 Macro (plus an additional, original Pentax bellows; both from around 1975, both in pristine order). Or possibly the Olympus 50 F/1.4 and the 85 F/2 or F2.8 (can't remember now; already out of my mind ).

 

f.
A 15 mm macro I would only get if it is corrected for at least a 10x to 20x magnification (think pictures of frame filling small insect eggs), has a tele- rather than wa-design, and comes with an extension tube which allow you to actually take photographs at those magnifications. I could in principle already get there with my enlarging lenses, just that I do not have the extension tubes to get that close-up, yet . Having looked at the options, I'll probably get a bellows set for this type of work, at some point in time.

 

BTW, I used to do macrophotography or microphotography if you like, for work, long time ago, of 2 mm items and smaller, which would fill the entire FoV, or 24mm x 36mm frame .

 

A good way to start with MFT, apart from getting an MFT camera obviously, is to get a Metabones EF-MFT Ultra 0.71X adapter for your Canon glass. OTOH, it may not work with Canon EF-S glass, but will work with 3rd party APS-C lenses, and obviously with all FF lenses. You'd still have AF if they are AF lenses of course.

 

Kind regards, Wim

[toni-a]

"something may not be as valuable as it first appears

and

"a goat, even if it flies"


The question is: to whom are you replying with these quote


Kind regards, Wim

I fact google isn't ideal for translating Arabic, correct for the second one " a goat even if it flies" as for the first one the closest translation is " doesn't matter how much you bake/shake the water it will be always water"


Of course I was referring to someone with fixed ideas here, that doesn't want to get convinced despite all the facts you and others gave him and still insists "a goat" even if it flies... So trying to convince him is just like baking water, he won't change...

[Brightcolours]

And yet, Tony, it is you who does not see the facts and just goes with who he likes. You always have the idea I have it wrong, and yet again I am not the one claiming nonsense. Lenses do not need shimming in order to get accurate AF. That is fact.

[Arthur Macmillan]

All of the lenses you mention are extremely attractive to me!  Olympus and Pentax are two of my favorite to convert (No surprises there, I am sure!)  It sounds as is you have done the hard work of disposing of them, and I don't wish to cause you additional pain.  Some of those are gems though.  Two have my name written all over them. 

 

I actually have the much maligned Asahi Pentax Takumar 135/2.5.  I don't think it is fully coated, But neither are Leica lenses unless they have changed this in the last decade or so.  Of this lens, Pentax forums calls it good consumer grade glass.  You know how people love to parrot what others say?  Everywhere I read:  "Consumer grade glass"  I give the lens 10/10.  Lord, is that a sharp lens!  And the colors are as true as your mother's love!  I really don't know what people want!  If I close my hand around it is completely hidden in my fist.  Dimensions, via my clipboard's built in ruler, so give or take my comparison:


Takumar 135/2.5:  100mm L x 60mm Dia. with built in magnetic held hood, weight: 0 (estimate )

EF 135/2L USM:    130mm L x 75mm Dia., Weight: 160 degrees   - See when I were my camera I hate when it points down!

 

I'm not a fool.  I bought the 135/2L because I loved the Tak 135/2.5 and wanted better, and USM.  Possibly if I find a real photographer (easy standard to reach:  Better than me, in other words) Who appreciates it, I will give it away.

 

Okay enough on drooling over old lenses.  Would you believe yesterday, I went out to photograph rare plants, and forgot I had put a 13mm tube on my 60mm/2.8 Macro.  It was set up with a ring light, so that the lens looks small between the flash ring and control unit.  It took me an hour to figure out why I could rarely AF. 


The EFS 60 F/2.8 is one of my favorite macro lenses.  I like depth of field in macro's.  Especially for documentation and comparison of plant species.  So - Just because I love the EFS 60 I wanted to use it on my 5D Mark II.  Don't wince!  I mean with the 13mm tube to give the mirror clearance!  Did I get a full frame pic?  Did the camera say, "Not gonna do it"?

 

RESULT:  I worked fine!  1.39x magnification on the sensor!!!  Clear, Sharp, and AF working in good light & no flash needed

                                        0.20x magnification possible at a distance way out at 0.1 meters (~1/4 foot) further out than my 180mm

                                          Macro's minimum distance. 

 

Why you ask?  Well the EFS 60 is my plant closeup king.  Currently my 70 D is dead, poetically enough, with Error 70.  I was sent to the market to pay for repairs but I bought some magic beans (5D Mark II).

 

I am going to my bullpen.  (Manual Focus lenses, and now this EFS lens On EF mount with Macro tube for protection!).  I will get the job done!  I have to.  It's a very important job!

 

Always a pleasure, talking to all of those who inspire me! 

 

Kinder Regards "Mac"