Home

Please support mflenses.com if you need any graphic related work order it from us, click on above banner to order!
SearchSearch MemberlistMemberlist RegisterRegister ProfileProfile Log in to check your private messagesLog in to check your private messages Log inLog in

lens coating: yellow vs. blue
Post new topic   Reply to topic
Home   Manual Focus Lenses
View previous topic :: View next topic  


PostPosted: Fri Oct 25, 2013 1:42 pm    Post subject: lens coating: yellow vs. blue Reply with quote
in front of me I have two copies of the same lens. The glass of one has a yellow tint, the other a blue/purple tint.
my question: does the color of the coating tell me which 'should' be the later, the 'better' coating?

well, I should try to find out be testing, resp. suppose that the one with the higher serial number, being the later, may have the better coating, but nevertheless I am curious if the color of the coating can tell us anything.

thank's


PostPosted: Fri Oct 25, 2013 1:51 pm    Post subject: Reply with quote
If these are Olympus Pen FT lenses, as Klaus once pointed to me, yellow is single coated and blue is multicoated.

I had three 38/1.8 lenses like that, two with yellow coating and one with blue coating. I only kept the last one.


PostPosted: Fri Oct 25, 2013 2:04 pm    Post subject: Reply with quote
Agree, yellow is usually single coated. Blue/ purple usually multi coated, also for other lenses than olympus.


PostPosted: Fri Oct 25, 2013 2:07 pm    Post subject: Reply with quote
Alex H wrote:
If these are Olympus Pen FT lenses, as Klaus once pointed to me, yellow is single coated and blue is multicoated.

I had three 38/1.8 lenses like that, two with yellow coating and one with blue coating. I only kept the last one.


haha, great, you are spot on, the lens in question is a Pen-F lens!
and I pretty much though that what you told me might be the case, thank you TONS to tell me this, also thank you to Klaus.


there is another thing about Pen-F lenses that has had me wondering but searching the net can't find any info on:

there seem to be 2 versions of rear bayonet on Pen-F lenses and two kind of rear caps: one cap closes tight on any Pen-F lens, other rear caps only close tight on some, but only loose on other Pen-F lenses. Why is that, anything that the type of bayonet tell us?
( when I had bought my first Pen-F > NEX adapter for my first Pen-F lens the adapter fit too tight, it was not possible to turn the lens into the adapter enough so that it engaged it's aperture lever. So be able to stop down the lens I reduced some parts on the adapter, only to find out that my second Pen-F lens I received later now would only fit loose and that adapter. I had to buy a new adapter which now is good for 'both' types of lenses )

Last edited by kuuan on Fri Oct 25, 2013 2:09 pm; edited 1 time in total


PostPosted: Fri Oct 25, 2013 2:09 pm    Post subject: Reply with quote
caspert79 wrote:
Agree, yellow is usually single coated. Blue/ purple usually multi coated, also for other lenses than olympus.


Mmm I have and old Blue Takumar that I think is single coated and I think the Primagon is single coated too (blue again) and the SMC Tak 50/1.4 is yellow/orange...


PostPosted: Fri Oct 25, 2013 2:13 pm    Post subject: Reply with quote
Quote:
there seem to be 2 versions of rear bayonet on Pen-F lenses and two kind of rear caps: one cap closes tight on any Pen-F lens, other rear caps only close tight on some, but only loose on other Pen-F lenses. Why is that, anything that the type of bayonet tell us?
( when I had bought my first Pen-F > NEX adapter for my first Pen-F lens the adapter fit too tight, it was not possible to turn the lens into the adapter enough so that it engaged it's aperture lever. So be able to stop down the lens I reduced some parts on the adapter, only to find out that my second Pen-F lens I received later now would only fit loose and that adapter. I had to buy a new adapter which now is good for 'both' types of lenses )


That is very interesting to know about adapters, Andreas. Someone I know had the same problem - the lens would not fit the adapter properly... I wish I knew it earlier...


PostPosted: Fri Oct 25, 2013 2:16 pm    Post subject: Reply with quote
The color reflection of coated indicate which colors have the best transmission.

Yellow, ambar, reflection indicate that the trasmission of the blue is the benefif. The suplementary color.

Purple reflection, green transmissiom is benefit

The coated was the changing over the times and fashions. Ie. A lens with coated reflections purple and ambar beneficy the central part of the spectral of the light -over yellow/green.

In other cases the coated changed by the different materials that the brand had, like CZJ MC coated.

Generaly, the oldest single coated had ambar, pale blue, pale purple and cyan.

Green, red, and vivid blue, yellow, purple indicate newer, MC, coated.


PostPosted: Fri Oct 25, 2013 2:18 pm    Post subject: Reply with quote
Is that the difference between Pen-F and Pen-FT lenses, maybe, that causes that??


PostPosted: Fri Oct 25, 2013 2:25 pm    Post subject: Reply with quote
Rick1779 wrote:
caspert79 wrote:
Agree, yellow is usually single coated. Blue/ purple usually multi coated, also for other lenses than olympus.


Mmm I have and old Blue Takumar that I think is single coated and I think the Primagon is single coated too (blue again) and the SMC Tak 50/1.4 is yellow/orange...


That yellow smc Takumar probably has radioactive (yellowed) glass? You make me doubt now. I believe most of my single coated lenses are yellowish.


PostPosted: Fri Oct 25, 2013 2:28 pm    Post subject: Reply with quote
Hey, there is a slight but important difference between the color of the coating and the color of the lens (glass)... Laughing Laughing Laughing

Last edited by kds315* on Fri Oct 25, 2013 2:31 pm; edited 1 time in total


PostPosted: Fri Oct 25, 2013 2:28 pm    Post subject: Reply with quote
caspert79 wrote:
Rick1779 wrote:
caspert79 wrote:
Agree, yellow is usually single coated. Blue/ purple usually multi coated, also for other lenses than olympus.


Mmm I have and old Blue Takumar that I think is single coated and I think the Primagon is single coated too (blue again) and the SMC Tak 50/1.4 is yellow/orange...


That yellow smc Takumar probably has radioactive (yellowed) glass? You make me doubt now. I believe most of my single coated lenses are yellowish.


yes the tak was the 50/1.4


PostPosted: Fri Oct 25, 2013 2:28 pm    Post subject: Reply with quote
kds315* wrote:
Hey, there is a slight but important difference between the color of teh coating and the color of the lens (glass)... Laughing Laughing Laughing


emh and how you define which is which?


PostPosted: Fri Oct 25, 2013 2:28 pm    Post subject: Reply with quote
And would we please NOT drift away from the topic....Right?!

Last edited by kds315* on Fri Oct 25, 2013 2:30 pm; edited 1 time in total


PostPosted: Fri Oct 25, 2013 2:29 pm    Post subject: Reply with quote
kds315* wrote:
And would we please NOT drift away from the topic....Right?!


Am I?


PostPosted: Fri Oct 25, 2013 2:31 pm    Post subject: Reply with quote
Why else would I have said that then?? It is about COATING COLOR, not glass color


PostPosted: Fri Oct 25, 2013 2:32 pm    Post subject: Reply with quote
kds315* wrote:
Why else would I have said that then?? It is about COATING COLOR, not glass color


Ok sorry then, but I still can get how to determine which is the coating color and which the lens one Embarassed


PostPosted: Fri Oct 25, 2013 2:36 pm    Post subject: Reply with quote
kds315* wrote:
Is that the difference between Pen-F and Pen-FT lenses, maybe, that causes that??


Klaus I take it you are referring to my question about the Bayonet?

actually off topic too, I should have chosen the title different, but may I continue to talk Pen-F lenses? ( maybe can be split into another thread? )

I have quite a few Pen-F(T) lenses in front of me, mixed Pen-F and Pen-FT. 'Currently' ( I remember others having had the issue ) I only have one on which no rear cap will lock but will stay too loose, and it's a Pen-FT lens. But trying all out at once I realized that on all the rest, on which the rear caps do close tight enough to stay on, some lock more tight and some lock more loose.

Looking close at the mount on a Pen-F(T) camera, and also at the adapter which works fine with any Pen-F lens, I can see that they have long 'spring blades' which are unusually long and 'deep' incorporated in the mount and they pull the lens tight into the mount before the final lock.

So my thoughts now are that there may not two distinct Pen-F bayonets, but that there is a big variation of 'thickness' of the concerned parts on the lens, and that this variation, because the mount on the camera is constructed as described above, doesn't matter when mounted on the camera but makes the fit of the rear cap too loose on some lenses.


PostPosted: Fri Oct 25, 2013 2:54 pm    Post subject: Reply with quote
Alex H wrote:
Quote:
there seem to be 2 versions of rear bayonet on Pen-F lenses and two kind of rear caps: one cap closes tight on any Pen-F lens, other rear caps only close tight on some, but only loose on other Pen-F lenses. Why is that, anything that the type of bayonet tell us?
( when I had bought my first Pen-F > NEX adapter for my first Pen-F lens the adapter fit too tight, it was not possible to turn the lens into the adapter enough so that it engaged it's aperture lever. So be able to stop down the lens I reduced some parts on the adapter, only to find out that my second Pen-F lens I received later now would only fit loose and that adapter. I had to buy a new adapter which now is good for 'both' types of lenses )


That is very interesting to know about adapters, Andreas. Someone I know had the same problem - the lens would not fit the adapter properly... I wish I knew it earlier...


most welcome Alex!
as written in my last reply to Klaus now I think that it may not just be 2 distinct lens mounts, but that Pen-F lenses simply have a big variation of how tight fit.

what's important though it that not every Pen-F adapter will work with every lens!
my own experience can be found in this thread: http://forum.mflenses.com/nex-adapter-recommendations-t42622.html
in short, the Pen-F>NEX from seller adplo works great, the one from Big-is not
and member "Pontus" here: http://forum.mflenses.com/how-i-chose-adapters-for-the-nex-t48572.html reports good experience with his from "kiwifotos"


PostPosted: Fri Oct 25, 2013 2:57 pm    Post subject: Reply with quote
DR.JUAN wrote:
The color reflection of coated indicate which colors have the best transmission.

Yellow, ambar, reflection indicate that the trasmission of the blue is the benefif. The suplementary color.

Purple reflection, green transmissiom is benefit

The coated was the changing over the times and fashions. Ie. A lens with coated reflections purple and ambar beneficy the central part of the spectral of the light -over yellow/green.

In other cases the coated changed by the different materials that the brand had, like CZJ MC coated.

Generaly, the oldest single coated had ambar, pale blue, pale purple and cyan.

Green, red, and vivid blue, yellow, purple indicate newer, MC, coated.


thank you very much for your very comprehensive answer Dr. Juan!!

thank you also Caspert and Rick for your interest and input


PostPosted: Fri Oct 25, 2013 3:20 pm    Post subject: Reply with quote
kds315* wrote:
Why else would I have said that then?? It is about COATING COLOR, not glass color


I'm not a glass technologist, nor a physicist nor an optician, still less a trouble-maker, but let's remember that there can indeed be a connection between coating colour and lens glasses. Although theoretically light transmitted by optical glass should be neutral and free of colour, some types do indeed have characteristics which require some 'after treatment' to obtain the balance the designers seeks. In such cases, lens makers can, and do, use different coatings to off-set these characteristics. Where manufacturers change the glass formulations during the life of a lens - perhaps because a particular glass ceases to be produced - then a different glass may require the coating to be changed to allow for it.


PostPosted: Fri Oct 25, 2013 4:35 pm    Post subject: Reply with quote
Found this on Google. It looks make sense to me.

Why do coated lenses look purple (or blue or green or whatever)?
http://rick_oleson.tripod.com/index-166.html


PostPosted: Fri Oct 25, 2013 5:27 pm    Post subject: Reply with quote
Thanks a lot Calvin, this is a very good source, still complicated for many I guess.

Still I don't get it why not invest a little effort to learn and understand about that
using google, as it is all there for free... Guess I'm just too "old school", SIGHHH

http://en.wikipedia.org/wiki/Photographic_lens_design

Last edited by kds315* on Fri Oct 25, 2013 5:44 pm; edited 1 time in total


PostPosted: Fri Oct 25, 2013 5:40 pm    Post subject: Reply with quote
kuuan wrote:
Alex H wrote:
Quote:
there seem to be 2 versions of rear bayonet on Pen-F lenses and two kind of rear caps: one cap closes tight on any Pen-F lens, other rear caps only close tight on some, but only loose on other Pen-F lenses. Why is that, anything that the type of bayonet tell us?
( when I had bought my first Pen-F > NEX adapter for my first Pen-F lens the adapter fit too tight, it was not possible to turn the lens into the adapter enough so that it engaged it's aperture lever. So be able to stop down the lens I reduced some parts on the adapter, only to find out that my second Pen-F lens I received later now would only fit loose and that adapter. I had to buy a new adapter which now is good for 'both' types of lenses )


That is very interesting to know about adapters, Andreas. Someone I know had the same problem - the lens would not fit the adapter properly... I wish I knew it earlier...


most welcome Alex!
as written in my last reply to Klaus now I think that it may not just be 2 distinct lens mounts, but that Pen-F lenses simply have a big variation of how tight fit.

what's important though it that not every Pen-F adapter will work with every lens!
my own experience can be found in this thread: http://forum.mflenses.com/nex-adapter-recommendations-t42622.html
in short, the Pen-F>NEX from seller adplo works great, the one from Big-is not
and member "Pontus" here: http://forum.mflenses.com/how-i-chose-adapters-for-the-nex-t48572.html reports good experience with his from "kiwifotos"


Andreas,

don't you find it hard to believe that Olympus would make lenses with such precises micro millimeter tolerances - and then be so sloppy about
the mount?? The engineer that I am finds that hard, if not impossible to believe, so there must be another, better explanation for that!!

And I'm only talking about the lenses, not some cheaply and carelessly made adapters!!


PostPosted: Fri Oct 25, 2013 5:43 pm    Post subject: Reply with quote
Well the original question was not why does coating look like it does, but rather whether the color indicated the age it was made in. As though amber coating = earlier, and blue = later. Oleson's article is very informative, but the simple truth is different manufactures were using amber and blue/purple coatings simultaneously. So while it may be a good indicator for a single manufacturer, it is not a general indicator of age.


PostPosted: Fri Oct 25, 2013 6:19 pm    Post subject: Reply with quote
Calvin thank you very much for this link!
just overflew it for now, but it seems to cover the theory very well. Best coating would be colorless then? Wink

Mos thank you very much for you input. I wonder if one could say that 'chances are' that blue / purple coatings are later than yellow?

kds315* wrote:
kuuan wrote:
Alex H wrote:
Quote:
there seem to be 2 versions of rear bayonet on Pen-F lenses and two kind of rear caps: one cap closes tight on any Pen-F lens, other rear caps only close tight on some, but only loose on other Pen-F lenses. Why is that, anything that the type of bayonet tell us?
( when I had bought my first Pen-F > NEX adapter for my first Pen-F lens the adapter fit too tight, it was not possible to turn the lens into the adapter enough so that it engaged it's aperture lever. So be able to stop down the lens I reduced some parts on the adapter, only to find out that my second Pen-F lens I received later now would only fit loose and that adapter. I had to buy a new adapter which now is good for 'both' types of lenses )


That is very interesting to know about adapters, Andreas. Someone I know had the same problem - the lens would not fit the adapter properly... I wish I knew it earlier...


most welcome Alex!
as written in my last reply to Klaus now I think that it may not just be 2 distinct lens mounts, but that Pen-F lenses simply have a big variation of how tight fit.

what's important though it that not every Pen-F adapter will work with every lens!
my own experience can be found in this thread: http://forum.mflenses.com/nex-adapter-recommendations-t42622.html
in short, the Pen-F>NEX from seller adplo works great, the one from Big-is not
and member "Pontus" here: http://forum.mflenses.com/how-i-chose-adapters-for-the-nex-t48572.html reports good experience with his from "kiwifotos"


Andreas,

don't you find it hard to believe that Olympus would make lenses with such precises micro millimeter tolerances - and then be so sloppy about
the mount?? The engineer that I am finds that hard, if not impossible to believe, so there must be another, better explanation for that!!

And I'm only talking about the lenses, not some cheaply and carelessly made adapters!!


right!
However my observation of various degrees of tightness of fit and sometimes too loose fit so that no cap stays and even will fall off entirely is based on how various original rear caps ( 6 in total ) fit on a bigger number of Pen-F lenses...only!
and once, but once only, I had found someone somewhere on the net mentioning difference of bayonet of Pen-F lenses as if it was common knowledge, but I have never found that page again

The observation that there are adapters that may fit some but be too tight resp. too loose for others I only added as additional proof that there seems to be a variation of 'thickness' of the mounting parts of the lens mounts, resp. because it may be helpful information for someone who has a badly fitting adapter.
Post new topic   Reply to topic
Home   Manual Focus Lenses
Goto page 1, 2, 3  Next
Page 1 of 3