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Eyepiece transmission test results

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#1 Paul G

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Posted 05 November 2014 - 11:59 AM

A little more information on the eyepiece transmission test report from Markus Ludes I and others have posted:

 

http://www.amateuras.../tips/tips3.htm

 

Lack of description of methodology was brought up by BillP in the Abbe vs Plossl thread so I went to the source and received the following info. The testing was performed by Konrad Horn Optik Messungen (Konrad Horn Optical Measurements), a German optics testing institute that specializes in UV-VIS-NIR spectroscopy in the range 185-3200 nm and provides measuring services for a variety of optics including optical fiber, prisms, lenses, etc. The equipment used is regularly tested and certified. I don't think we need to worry about the accuracy of the figures shown in the above link.



#2 Eddgie

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Posted 05 November 2014 - 12:17 PM

Does not matter how perfect the lab methods were.   Noting is as good as subjective testing.. I read that right here on CN.

 

These are not the droids we're looking for....  (The force is weak in this one, Obi Wan)



#3 SteveC

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Posted 05 November 2014 - 12:35 PM

Thanks , Paul.

 

It's a great snapshot in time. The ZAO's and Pentax orthos performed as expected. 



#4 CeleNoptic

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Posted 05 November 2014 - 01:03 PM

Well, it's the same outdated table  BillP was talking about. Nothing new here.



#5 alnitak22

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Posted 05 November 2014 - 01:11 PM

Does not matter how perfect the lab methods were.   Noting is as good as subjective testing.. I read that right here on CN.

 

These are not the droids we're looking for....  (The force is weak in this one, Obi Wan)

Ha! Amazing what you can read here on CN!



#6 Lance1234

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Posted 05 November 2014 - 03:54 PM

Dang, look at those low numbers for the Panoptic.  Guess I should have bought the 41mm ZAO instead... :lol:



#7 Paul G

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Posted 05 November 2014 - 04:58 PM

Dang, look at those low numbers for the Panoptic.  Guess I should have bought the 41mm ZAO instead... :lol:

 

Keep in mind it takes about an 8% difference for it to be visually detectable.



#8 EuropaWill

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Posted 05 November 2014 - 08:50 PM

 

Dang, look at those low numbers for the Panoptic.  Guess I should have bought the 41mm ZAO instead... :lol:

 

Keep in mind it takes about an 8% difference for it to be visually detectable.

 

Tell that to all the people that snatched up 99% dielectric diagonals over the past few years  :p



#9 ibase

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Posted 05 November 2014 - 09:58 PM

The TV-20mm plossl is top dog with best transmission of 98.88% - no wonder I can see the flag on the moon whenever I use it Lol :lol:

 

e0108f8ec7d762537b15ba9ce05d3369.jpg

 

Best,


Edited by ibase, 05 November 2014 - 09:58 PM.


#10 CeleNoptic

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Posted 05 November 2014 - 10:35 PM

The TV-20mm plossl is top dog with best transmission of 98.88% - no wonder I can see the flag on the moon whenever I use it Lol :lol:

 

e0108f8ec7d762537b15ba9ce05d3369.jpg

 

Best,

Hernando,

Are you sure it's the flag and not debris trapped between the lenses? :lol:  :lol:  :lol:



#11 ibase

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Posted 06 November 2014 - 01:53 AM

 

The TV-20mm plossl is top dog with best transmission of 98.88% - no wonder I can see the flag on the moon whenever I use it Lol :lol:

 

e0108f8ec7d762537b15ba9ce05d3369.jpg

 

Best,

Hernando,

Are you sure it's the flag and not debris trapped between the lenses? :lol:  :lol:  :lol:

 

Vlad,

 

Lol :lol: Not really, the stars and stripes are clearly resolved, so yes, it's the flag alright. :)

 

Best,



#12 Mariner@sg

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Posted 06 November 2014 - 03:45 AM

 

 

The TV-20mm plossl is top dog with best transmission of 98.88% - no wonder I can see the flag on the moon whenever I use it Lol :lol:

 

e0108f8ec7d762537b15ba9ce05d3369.jpg

 

Best,

Hernando,

Are you sure it's the flag and not debris trapped between the lenses? :lol:  :lol:  :lol:

 

Vlad,

 

Lol :lol: Not really, the stars and stripes are clearly resolved, so yes, it's the flag alright. :)

 

Best,

 

 

Didn't realise TV plossls have the ability to time warp! The flag is already faded to total white by now! :lol:



#13 ibase

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Posted 06 November 2014 - 04:26 AM

Lol Didn't anyone tell you that Brandon is NOT the only magical eyepiece around? :)

 

Best,



#14 Paul G

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Posted 06 November 2014 - 05:17 AM

 

 

Dang, look at those low numbers for the Panoptic.  Guess I should have bought the 41mm ZAO instead... :lol:

 

Keep in mind it takes about an 8% difference for it to be visually detectable.

 

Tell that to all the people that snatched up 99% dielectric diagonals over the past few years  :p

 

 

The main reason to use a dielectric diagonal is it can be cleaned without risk of scratching it.



#15 russell23

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Posted 06 November 2014 - 08:39 AM

Does not matter how perfect the lab methods were.   Noting is as good as subjective testing.. I read that right here on CN.

 

These are not the droids we're looking for....  (The force is weak in this one, Obi Wan)

 

I know what you mean.   My precision electronic eyes tell me all the time exactly what reality is.   Can you imagine what this hobby would be like if everyone had different eyes and a biological eye-brain processing system?   Some people might actually see things differently than others if that was the case. Boy taht sure would lead to a lot of debates in this forum.  Fortunately, we have bench tests that perfectly calibrate to the eye/brain interface to tell us exactly what each one of us is seeing.      


Edited by russell23, 06 November 2014 - 08:40 AM.


#16 Sarkikos

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Posted 06 November 2014 - 09:42 AM

Does not matter how perfect the lab methods were.   Noting is as good as subjective testing.. I read that right here on CN.

 

These are not the droids we're looking for....  (The force is weak in this one, Obi Wan)

 

I agree with the literal interpretation of this post.    

 

:grin:

Mike



#17 Sarkikos

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Posted 06 November 2014 - 09:45 AM

The TV-20mm plossl is top dog with best transmission of 98.88% - no wonder I can see the flag on the moon whenever I use it Lol :lol:

 

I do recall EdZ saying that the TV 15 and 20 were the best of the TV Plossls. :thinking:

 

:grin:

Mike



#18 Sarkikos

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Posted 06 November 2014 - 09:46 AM

 

Does not matter how perfect the lab methods were.   Noting is as good as subjective testing.. I read that right here on CN.

 

These are not the droids we're looking for....  (The force is weak in this one, Obi Wan)

 

I know what you mean.   My precision electronic eyes tell me all the time exactly what reality is.   Can you imagine what this hobby would be like if everyone had different eyes and a biological eye-brain processing system?   Some people might actually see things differently than others if that was the case. Boy taht sure would lead to a lot of debates in this forum.  Fortunately, we have bench tests that perfectly calibrate to the eye/brain interface to tell us exactly what each one of us is seeing.      

 

 

:lol:

 

Mike



#19 SandyHouTex

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Posted 06 November 2014 - 11:33 AM

A little more information on the eyepiece transmission test report from Markus Ludes I and others have posted:

 

http://www.amateuras.../tips/tips3.htm

 

Lack of description of methodology was brought up by BillP in the Abbe vs Plossl thread so I went to the source and received the following info. The testing was performed by Konrad Horn Optik Messungen (Konrad Horn Optical Measurements), a German optics testing institute that specializes in UV-VIS-NIR spectroscopy in the range 185-3200 nm and provides measuring services for a variety of optics including optical fiber, prisms, lenses, etc. The equipment used is regularly tested and certified. I don't think we need to worry about the accuracy of the figures shown in the above link.

 

Actually you do.  Before buying into this test we should all ask how it was performed which can have a drastic effect on the results.  And it they just tested one eyepiece of each type, than at best, no generalizations can be made to that type of eyepiece.  In other words, if the tested just one 19mm Panoptic, it is not appropriate to generalize that transmission level to all 19mm Panoptics.  The sample size is obviously too small.  Testing 101.



#20 russell23

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Posted 06 November 2014 - 11:38 AM

 

A little more information on the eyepiece transmission test report from Markus Ludes I and others have posted:

 

http://www.amateuras.../tips/tips3.htm

 

Lack of description of methodology was brought up by BillP in the Abbe vs Plossl thread so I went to the source and received the following info. The testing was performed by Konrad Horn Optik Messungen (Konrad Horn Optical Measurements), a German optics testing institute that specializes in UV-VIS-NIR spectroscopy in the range 185-3200 nm and provides measuring services for a variety of optics including optical fiber, prisms, lenses, etc. The equipment used is regularly tested and certified. I don't think we need to worry about the accuracy of the figures shown in the above link.

 

Actually you do.  Before buying into this test we should all ask how it was performed which can have a drastic effect on the results.  And it they just tested one eyepiece of each type, than at best, no generalizations can be made to that type of eyepiece.  In other words, if the tested just one 19mm Panoptic, it is not appropriate to generalize that transmission level to all 19mm Panoptics.  The sample size is obviously too small.  Testing 101.

 

 

And regarding the TV eyepieces there have been upgrades to coatings.  That data is pretty old.  Based upon my experiences the Pans manufactured more recently do have higher transmission than much older Pans.  I haven't bench tested - just my subjective visual impression with eyepiece swaps on multiple nights.

 

Dave



#21 Paul G

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Posted 06 November 2014 - 05:57 PM

 

A little more information on the eyepiece transmission test report from Markus Ludes I and others have posted:

 

http://www.amateuras.../tips/tips3.htm

 

Lack of description of methodology was brought up by BillP in the Abbe vs Plossl thread so I went to the source and received the following info. The testing was performed by Konrad Horn Optik Messungen (Konrad Horn Optical Measurements), a German optics testing institute that specializes in UV-VIS-NIR spectroscopy in the range 185-3200 nm and provides measuring services for a variety of optics including optical fiber, prisms, lenses, etc. The equipment used is regularly tested and certified. I don't think we need to worry about the accuracy of the figures shown in the above link.

 

Actually you do.  Before buying into this test we should all ask how it was performed which can have a drastic effect on the results.  And it they just tested one eyepiece of each type, than at best, no generalizations can be made to that type of eyepiece.  In other words, if the tested just one 19mm Panoptic, it is not appropriate to generalize that transmission level to all 19mm Panoptics.  The sample size is obviously too small.  Testing 101.

 

 

It is what it is until someone forks over the money to fund measuring multiple samples of each. Any volunteers? ;)

 

Since there's no evidence that there is visually detectable (and since these are eyepieces that's all that matters) unit to unit variation in eyepieces from Pentax, TeleVue, Zeiss and others in that test, I'm not put off by a sample size of one. And it's not like this is some difficult task, these are routine measurements like length or width for a company that specializes in measuring such things with calibrated equipment made specifically for that task, no need to treat it like it's a scientific experiment. Common Sense 101.

 

If you can show evidence that there is visible unit to unit variation in eyepieces from these companies then sample size would be more important in drawing conclusions.



#22 slack

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Posted 06 November 2014 - 06:12 PM

russell23, the only Panoptic listed there is the long extinct 15mm. It seems odd to me that testing included only the least popular focal length of a very popular line.




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