108 replies to this topic

[j.gardavsky]

Well, gang, I hate to quote Lenin, but “What is to be done?” Any ideas?

 

Dark skies.

 

Jack

1. AR multicoatings which don't catch electrostatic charging.)*

 

And optionally:

2. Optics assembly in clean air boxes with clean gloves.

3. Pump the air out and purge the eyepices with some clean inert gas.

4. Seal them once for ever.

 

In my historical collection,

the only strictly clean eyepieces are the old Steinheil and Reichert eyepieces,

without any AR coatings.

Easy to clean, and to screw together after the cleaning.

 

Best,

JG

 

)* In some eyepieces, the dust particles are sticking on the lenses like ****, and it takes time to remove them.

[Scott99]

Great list - I was too squeamish to make it past the first few bullet points though!    it's difficult reading

 

I am definitely in the camp of people that do not want to shine a flashlight into their eyepieces - don't ask, don't tell type situation    I did notice a couple of tiny coating defects in my Pentax XW's...so I don't look at them too closely while cleaning

Edited by Scott99, 17 June 2024 - 11:38 AM.

[denis0007dl]

Great list - I was too squeamish to make it past the first few bullet points though!    it's difficult reading

 

I am definitely in the camp of people that do not want to shine a flashlight into their eyepieces - don't ask, don't tell type situation    I did notice a couple of tiny coating defects in my Pentax XW's...so I don't look at them too closely while cleaning

I heard you, 

 

I saw same, more or less coatings defect on many eyepieces, many prisms (both diagonals and binoviewers), many telescope lenses, many mirror diagonals, many barlow lenses (even most expensive ones), including my LZOS 180mm f/7 expensive APO who not only as sayed have thousands of tiny scratches on lenses, bubbles inside lenses, but also several uncoated areas of lenses (small uncoated circles), and I still love it 

 

I teached myself to enjoy in optical performance, and to less stare into many optical imperfections because perfection in that regard is not nearly close .

 

And I really finally feel lighter and better, bringing all thrse things to live, sharing it with you, and Im glad some of you are sharing sometimes simillar experiences...

 

Denis

Edited by denis0007dl, 17 June 2024 - 12:47 PM.

[Starman1]

A funny story:

I bought and used an APM 30mm Ultra Flat Field eyepiece.

I evaluated it with my 29 point analysis, and liked the eyepiece a lot.

 

A couple years later (I was selling them in my business, then), I had a few returned because of dirt particles inside.

I dismantled each and blew the dirt particles away and the customers were happy.

 

So I looked at my own 30mm, after thinking about it, and saw a veritable vegetable garden in there.

(maybe a hundred particles large enough to be visible), so I dismantled it and cleaned every lens.

One lens even had a sticky coating on it.  Eek!

I reassembled it and looked at it again.  Now I could see maybe 5 or 6 small particles and nothing else.

 

I used the eyepiece again and saw no visible difference.  I felt a lot better because the eyepiece was cleaner (not perfect) inside.

 

Later, I saw a factory picture of an assembler putting eyepieces together at the same factory that produced the 30mm UFF:

--no hair cover

--no mask

--no gloves

--at a desk in a large open room

 

Seriously?

 

And it's no better in Japan.

 

So, I try to look through the eyepieces and not at them.  I hold them up to the light to see if there are any chunks of debris I can see, and, if not, I use the eyepiece.

Are they possessed of ultra-fine dust, bubbles in the lenses, scratches, internal paint gaps or blems, or other flaws like coating pinholes (ultra common with Pentax)?  For sure.

Do I wish the manufacturers would turn out cleaner eyepieces?  Sure.

Do I expect them to?  Nope.

 

One thing I would say to other observers I see in the field: Clean Your Eyepieces!

Most eyepieces I see are filthy.  If they're that bad on the outside, it's no wonder we don't notice the junk inside.

[JAC51]

With all the floaters in my eyeball I don’t think my eyes were assembled in a clean room either.

Must complain to the manufacturer.

Edited by JAC51, 17 June 2024 - 12:57 PM.

[j.gardavsky]

...  and wash your face before putting your eye on the eyepiece,

 

JG

[denis0007dl]

I experienced many interesting thing, and one of them was, for example, when I received expensive brandnew eyepiece (wont name it nor company who sell), and it have thousands small oil drops inside, I hardly but at end sucesfully photographed them and picts sent to seller (BTW very experienced and reliable EU seller), and seller offer me to clean it with pleasure.

 

Once he receive and inspected it, under hard examination, he saw nothing 

 

He even sent me simillar images under certan angle but without any visible oil spot.

 

I sayed great, ship same ep to me again.

I receive it, and I make even full video (my wife make constamd record) where I get package in my hands from postman, I imeadiately open package, and check it, and I see same hundreds oil drops, and forward it to seller.

 

He couldnt beleive, but great I had evidence.

He insist to ship ep to him again, and when he receive it again, he again see noting 

 

So, sometimes, even often, I see many many imperfections which other ppl can not notice no matter what, but many times imperfrctions are super easy visible at first, to any person,  

like:

 

1. outer optical/lens scratches,

2. chipped lens or mirror edges,

3. big air bubbles inside optics, 

4. bigger non coated outer lens sourfaces,

5. other coatings imperfections on outer lenses!

 

Kind regards to all,

Denis

[CrazyPanda]

A funny story:

I bought and used an APM 30mm Ultra Flat Field eyepiece.

I evaluated it with my 29 point analysis, and liked the eyepiece a lot.

 

A couple years later (I was selling them in my business, then), I had a few returned because of dirt particles inside.

I dismantled each and blew the dirt particles away and the customers were happy.

 

So I looked at my own 30mm, after thinking about it, and saw a veritable vegetable garden in there.

(maybe a hundred particles large enough to be visible), so I dismantled it and cleaned every lens.

One lens even had a sticky coating on it.  Eek!

I reassembled it and looked at it again.  Now I could see maybe 5 or 6 small particles and nothing else.

 

I used the eyepiece again and saw no visible difference.  I felt a lot better because the eyepiece was cleaner (not perfect) inside.

 

Later, I saw a factory picture of an assembler putting eyepieces together at the same factory that produced the 30mm UFF:

--no hair cover

--no mask

--no gloves

--at a desk in a large open room

 

Seriously?

 

And it's no better in Japan.

 

So, I try to look through the eyepieces and not at them.  I hold them up to the light to see if there are any chunks of debris I can see, and, if not, I use the eyepiece.

Are they possessed of ultra-fine dust, bubbles in the lenses, scratches, internal paint gaps or blems, or other flaws like coating pinholes (ultra common with Pentax)?  For sure.

Do I wish the manufacturers would turn out cleaner eyepieces?  Sure.

Do I expect them to?  Nope.

 

One thing I would say to other observers I see in the field: Clean Your Eyepieces!

Most eyepieces I see are filthy.  If they're that bad on the outside, it's no wonder we don't notice the junk inside.

I'll post these images here as it's relevant.

 

Here are my 12.5mm and 9mm Takahashi TPLs

 

12.5mm before cleaning internally (eye lens had been freshly cleaned before that image was taken)

 

12.5mm TPL after cleaning (all surfaces)

 

9mm TPL - factory new

 

I introduced some larger specks of dust and left some residue in the 12.5mm TPL but you can see it's much better than it was, and FAR better than the 9mm TPL.

 

At some point I'll open the 9mm TPL and clean it.

 

Whether I can see the difference or not may require specific testing in conditions of extremely good transparency, which I may not always have. So I would rather clean the eyepiece and KNOW that it is performing at its absolute best, especially since the entire point of such an eyepiece is maximal contrast.

 

My thinking is this: the differences from one premium eyepiece to the next are subtle at best. The impact of such dust is likely also subtle, at best. But if we're already dealing in subtleties, that means that relatively speaking, the presence of that level of dust is significant.

 

I have yet to see any eyepiece as dirty as Ohi-made eyepieces. I've seen this level of contamination in Fujiyamas, Takahashi Abbe Orthos, and now the TPLs. I've never seen this level of junk in other makes from premium to ultra cheap. The Barsta "red line" set I bought for $28 was basically spotless.

Edited by CrazyPanda, 17 June 2024 - 01:30 PM.

[Mike B]

Great list - I was too squeamish to make it past the first few bullet points though!    it's difficult reading

 

I am definitely in the camp of people that do not want to shine a flashlight into their eyepieces - don't ask, don't tell type situation    I did notice a couple of tiny coating defects in my Pentax XW's...so I don't look at them too closely while cleaning

No shinola there!

 

Okay, emboldened by Dennis poking the hornet’s nest- I’ll take a swat at the pin-Jah-tah! 

There was a boat loada green silkscreened items on his list- many of which I’ve owned, used, & enjoyed- and still have a few of! Now, the marketing talk on them sez Tele Vue visually inspects each and every one prior to releasing to their retailers. Commendable, indeed!.. and seemingly a unique QC measure Even so, mebbe their visual inspection regimen is no better than the average CNer who can’t “see the dust” on their brand-X eyepieces until utilizing certain special techniques? If this issue is so pervasive, why is it just NOW coming to light (pun intended?)

 

Plus, with the screamingly good performance many of us are seeing thru our (apparently, to be assumed as dusty ) EPs, one has to wonder   how much all this brouhaha really matters? Yes, I’d like the mental comfort of knowing my glass is sparkling clean & smooth! Yet I’ve enjoyed such amazing heavenly views- and NOT just recently thru TPL’s & Masuyama’s, but going waay back, & thru a variety of EPs! Makes me wonder whether Scott’s “Don’t ask” wisdom is the better road to take?

 

Another take on this, which I find very sobering, is if one does the math on the atmo we’re all looking thru, even looking straight up, if you compressed the column of air to the density of water, it’d be ~32 feet deep, fulla dirt & pollen & dust, and roiling it’s way across our FoV like a river! Considering THAT mess, what’s a li’l dust between friends? 

 

As another wise guy has written “For now we see thru a glass, darkly….” And that’s on a good nite!

[leonard]

 

   

 

 

I have yet to see any eyepiece as dirty as Ohi-made eyepieces. I've seen this level of contamination in Fujiyamas, Takahashi Abbe Orthos, and now the TPLs. I've never seen this level of junk in other makes from premium to ultra cheap. The Barsta "red line" set I bought for $28 was basically spotless.

 

 

    Hard to beleave , but the truth is right in our face . Thanks for posting the pics .

        
         At high power , there is no way I can be convinced that much dirt will not impede the image .

                    It maybe on the shuttle side but it will be .

      
                        Simple glass , simple task , keep them clean .

[mountain monk]

An analogy. Sometimes famous old oil paintings are cleaned. In some cases they have been viewed for hundreds of years by millions of people. When, finally, the cleaned painting is displayed with glee, the reactions are divided. Some exclaim it’s superior beauty; others are upset—they much preferred the older, dirty version because it’s what they are accustomed to!

You can only please some of the people some of the time.

 

Dark skis.

 

Jack

[CrazyPanda]

they much preferred the older, dirty version because it’s what they are accustomed to!

 

Understandable. You'll never in a million years get me to enjoy motion smoothing on modern TVs, or movies filmed at higher frame rates. The smoothed motion makes everything look like a cheap soap opera.

Yes, technically the smoother motion is superior, but I'm so used to 24-30FPS movies that anything greater feels unnatural and non-cinematic.

[mountain monk]

So, the conundrum: You have dusty, scratched, chipped, foggy TPL, whatever, and.a clean TPL. Jupiter comes around and you aim your first-rate scope-Tak, TEC, AP, whatever your druthers, and start changing eps. And Lo, you do see more  exquisite detail in the clean ep. What to do? Send it back? Sue? Clean it yourself? Start a business cleaning them? Do the modern shrug and go on with them? Generate excuses for various members of the supply chain? Who knows.

 

Dark skies.

 

Jack

[j.gardavsky]

The dust problem on and in the optics has been known before this discussion has started.

 

The theoretical backgrounds for the lost of the modulation transfer due to the dust layers have been developed in the U.S. around 1980, and I have some of the article reprints from those times in my archive, also because I have been involved in a related research.

 

Years ago, I have started replacing the eyepieces I used to have, with the Carl Zeiss (West) and Leitz/Leica eyepieces from the research grade microscopes.

Even if these are still not completely free from dust, the count of the dust particles is low, in difference to the other eyepieces I used to have before.

 

These fairly clean eyepieces have allowed to see some not so easy planetary nebulae through a 6" F/5 refractor and under my typically Bortle 4 skies,

FP J1912-0331 (Frew and Parker) in Aquila

PC-19 in Aquila

Abell 74 in Vulpecula

DeHT 5 in Cepheus

PaRasMoMi 1 in Monoceros

Pu-We 1 in Lynx

which otherwise would require more aperture and better skies.

 

And I have also completed visual observations of 50 supernova remnants, including the relicts of the SNRs turning into the shells of molecular clouds.

 

Clear skies, and great views through the clean optics,

JG

[denis0007dl]

Have to say, my Takahashi TPL, TOE and Vixen HR eyepieces, despite a lot of optical imperfections, provide incredible optical performance!

Denis

[TheChosen]

This is one of the reasons (not the main reason but one of them) I sold my Baader Zoom. I don't mind some specs of dust if they are out of focus and not impacting optical performance (just look at a primary mirror) but Zooms are different. At their lowest power the focus is right at the bottom lens and any small speck is magnified many-fold and very clearly visible and in the way. Very sharp as well even when looking at the Sun in white light or the featureless parts of the Moon.

 

This idea that a multi million dollar air purifying environment is needed is not correct. A simple consumer grade air purifier/filter will greatly reduce the amount of visible particles in the air. They simply don't care. They also don't make it easy at all to disassemble the eyepiece and clean it. The particles of the zoom were stuck in the middle of the upper two lens, tightly sealed together. Impossible to clean.

 

When I was selling my zoom one of the interested guys said he was interested only if there were no particles inside. I was like... yeah mate, good luck with that. Every zoom has them. Try buying a new one and be prepared to return it to Baader several times until they get it right (I've seen the stories online). 

 

My SVBony 7-21mm has them as well but for a 50$ eyepiece I don't bother to clean them and I don't expect top quality.. but Baader was a different story, I expected more from a reputable company such as them.

[PKDfan]

This is one of the reasons (not the main reason but one of them) I sold my Baader Zoom. I don't mind some specs of dust if they are out of focus and not impacting optical performance (just look at a primary mirror) but Zooms are different. At their lowest power the focus is right at the bottom lens and any small speck is magnified many-fold and very clearly visible and in the way. Very sharp as well even when looking at the Sun in white light or the featureless parts of the Moon.

This idea that a multi million dollar air purifying environment is needed is not correct. A simple consumer grade air purifier/filter will greatly reduce the amount of visible particles in the air. They simply don't care. They also don't make it easy at all to disassemble the eyepiece and clean it. The particles of the zoom were stuck in the middle of the upper two lens, tightly sealed together. Impossible to clean.

When I was selling my zoom one of the interested guys said he was interested only if there were no particles inside. I was like... yeah mate, good luck with that. Every zoom has them. Try buying a new one and be prepared to return it to Baader several times until they get it right (I've seen the stories online).

My SVBony 7-21mm has them as well but for a 50$ eyepiece I don't bother to clean them and I don't expect top quality.. but Baader was a different story, I expected more from a reputable company such as them.

Hi The Chosen !!

Not IME. I'm sorry your experience suboptimal but I've never had that issue and use it alot terrestrially.

A Mark IV.

No visible dust at all.

Of course YMMV.

CS

[TheChosen]

Hi The Chosen !!

Not IME. I'm sorry your experience suboptimal but I've never had that issue and use it alot terrestrially.

A Mark IV.

No visible dust at all.

Of course YMMV.

CS

Are you sure? Try this..

 

Put it in 24mm , and then without a telescope look through it in the direction of a very bright light.

[PKDfan]

Are you sure? Try this..

Put it in 24mm , and then without a telescope look through it in the direction of a very bright light.

Done the led test already Chosen.

Some are unfortunately luckier than others.


CS

[Mike B]

Have to say, my Takahashi TPL, TOE and Vixen HR eyepieces, despite a lot of optical imperfections,

provide incredible optical performance!

Denis

 

Some are unfortunately luckier than others.

Am thinking “Luck” plays a rather minimal role in this… as Denis has previously quoted the advice of looking not AT the glass, but instead THRU it! For his efforts, it seems as tho he enjoys incredible views!  

[PKDfan]

Am thinking “Luck” plays a rather minimal role in this… as Denis has previously quoted the advice of looking not AT the glass, but instead THRU it! For his efforts, it seems as tho he enjoys incredible views!

Hi Mike !!

Well it may not be all luck of the draw but i HIGHLY AGREE that a quick light test and if on the surface of it (ha!) It seems clean MOVE ON to its real purpose without digging further(!) into it.


For me driving gasps awes and OMGing type stuff are the only important criteria, so a results driven approach, while always retaining an easy on the eye feeling are my most important attributes.


I think we might have this as an example of an eyepiece made on a monday or friday thing like cars and trucks.

Get a wednesday one !!



CS
Lance
P.s. a clean eyepiece is next to godliness and cleaning what looked clean and after REALLY clean was substantial improvement substantial meaning noticeable.
P.p.s. don't get mixed up & accidently put your eyepiece (or 2X Barlow) in a plastic bag that once held icing sugar.
P.p.p.s. does NOT make the item palatable but a nice lick clean anyways. Not!

Edited by PKDfan, 18 June 2024 - 12:47 PM.

[Mike B]

Jah! Dissembling & cleaning a zoom  NOT on my bucket list!

 

May thine “optical emergencies” never emerge!

 

… and if they ever do, may thee successfully lick thy problem! 

Edited by Mike B, 18 June 2024 - 02:45 PM.

[denis0007dl]

Just found interesting article about lens scratches, its well worth to check it out

https://www.cloudyni...tings-now-what/

[Starman1]

Just found interesting article about lens scratches, its well worth to check it out

https://www.cloudyni...tings-now-what/

After reading that thread, I wanted to ask, "Have you cleaned the lens?"

I had the suspicion some of what was thought to be scratches were actually foreign materials on the lens surface.

[betacygni]

I purpose an experiment. Someone take one of your clean eyepieces. Do some observing for a baseline. Now sprinkle a little flour (or your preferred dust proxy) onto it. How much “dust” until performance is noticeably diminished? Would be an interesting test.