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Equipment Discussions >> Reflectors

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tag1260
scholastic sledgehammer
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Reged: 10/07/12

Loc: Ohio, USA
Blackening mirror edges?
      #5711573 - 03/03/13 09:53 PM

Can someone tell me the purpose of blackening the edges of your mirror? Will they ALL benefit from it?
Thanks
.


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Jason D
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Loc: California
Re: Blackening mirror edges? new [Re: tag1260]
      #5711612 - 03/03/13 10:11 PM

Quote:

Can someone tell me the purpose of blackening the edges of your mirror? Will they ALL benefit from it?
Thanks
.




In theory, to minimize light scatter which in turn will enhance contrast? In real life, the difference will be subtle to none. Do not have high expectations.

Jason


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GlennLeDrew
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Re: Blackening mirror edges? new [Re: Jason D]
      #5711756 - 03/03/13 11:44 PM

One can calculate the potential contribution of scattered light from a bevel, by comparing the projected area of the bevel to the area of the mirror. For example, a 1/8" bevel on a 12" mirror has 4.3% the area of the mirror. I would most definitely blacken a bevel of this relative area. Actually, I'd be strongly tempted to so treat *all* bevels on both primary and secondary.

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Jason D
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Re: Blackening mirror edges? new [Re: GlennLeDrew]
      #5711772 - 03/03/13 11:56 PM

But the bevel will reflect star light towards the inner OTA walls and if the inner wall is flocked then most of it will not make it to the eyepiece.
Granted the bevel surface is not as polished and some of the scattered light will make it to the eyepiece but I would expect that to be minute.
As an experiment, a front aperture can be placed at the OTA/UTA opening to block star light from reaching the bevel area to see how much of a difference it will make at the eyepiece.

Jason


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Jarad
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Re: Blackening mirror edges? new [Re: Jason D]
      #5712021 - 03/04/13 07:38 AM

It depends a lot on the design of the scope. The bevel is less of an issue in a solid tube OTA. In a truss dob, though, it is possible for light from an off-axis object (like the moon) to hit the bevel at an angle where it will reach the focuser.

Also, there is no downside to blackening the bevel. It is easy to do with a chisel-tip marker, takes maybe 30 seconds once you have access to the mirror.

Jarad


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Mirzam
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Reged: 04/01/08

Loc: Lovettsville, VA
Re: Blackening mirror edges? new [Re: Jason D]
      #5712025 - 03/04/13 07:42 AM

One place where blackening is important is the partially aluminized exposed edge of the secondary visible from the eyepiece, unless of course one is using a secondary shroud.

I have seen major glare using a 100 degree afov eyepiece that was solved by blackening the exposed secondary edge. If you have a steady hand you may as well get the bevel at the same time--just don't get paint on the mirror surface!

JimC


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FirstSight
Duke of Deneb
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Reged: 12/26/05

Loc: Raleigh, NC
Re: Blackening mirror edges? new [Re: Mirzam]
      #5712046 - 03/04/13 08:09 AM

One potential downside of blackening the secondary edge with a black marker is when you clean the mirror (and use any sort of cleaning solution that might potentially act as a solvent) you risk dissolving just enough of the marking to make a smeary mess.

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dcoyle
professor emeritus


Reged: 10/11/05

Loc: Turbulent but dark skies, N.M.
Re: Blackening mirror edges? new [Re: FirstSight]
      #5712265 - 03/04/13 10:45 AM

+1 on felt tip smear.

Black pigmented 5 minute epoxy is more resistant to solvents.

Dan


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Sarkikos
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Re: Blackening mirror edges? new [Re: dcoyle]
      #5712348 - 03/04/13 11:42 AM

I blacken the bevels of primary and secondary with flat-black paint, such as supplied by Duchek. I tend to avoid "permanent" black marker. In my very dewy region it is not so permanent.

Blackening the bevel is easy to do. It might make only a vanishingly small improvement in many scopes. But it is so easy to do. Just do it and don't try to figure out beforehand the probable magnitude of the improvement. By the time you figure it out, you could have already painted the bevels. Unless you're one of those types who enjoy making precise measurements and mathematically formulizing all these things.

Use a bright light and wear a strong pair of those reading glasses you can buy for cheap at bargain stores.


Mike


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Starman1
Vendor (EyepiecesEtc.com)
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Reged: 06/24/03

Loc: Los Angeles
Re: Blackening mirror edges? new [Re: Jarad]
      #5712770 - 03/04/13 03:46 PM

Quote:

It depends a lot on the design of the scope. The bevel is less of an issue in a solid tube OTA. In a truss dob, though, it is possible for light from an off-axis object (like the moon) to hit the bevel at an angle where it will reach the focuser.

Also, there is no downside to blackening the bevel. It is easy to do with a chisel-tip marker, takes maybe 30 seconds once you have access to the mirror.

Jarad



1) During cleaning, some of the blackening may run/dissolve and get onto the reflective surface
2) When the mirror is recoated, removing the blackening on the mirror may be nearly impossible to do completely and the residual may contaminate the coating process.
3) The reflection from the beveled edge could only get into the light path if the inside of the scope around the mirror was white and scattered light was reflecting from the inside of the scope, off the bevel, and into the light path. That's a highly unlikely scenario.
4) Whatever chemical or solvent is present in the darkening agent (paint, ink, etc), there is the possibility for it to get into the aluminum at the edge of the mirror and cause contamination of the aluminum.

I do NOT recommend darkening the bevel on a primary mirror for the above reasons.


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careysub
Carpal Tunnel
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Reged: 02/18/11

Loc: Rancho Cucamonga, CA
Re: Blackening mirror edges? new [Re: Starman1]
      #5712835 - 03/04/13 04:20 PM

Quote:

...
I do NOT recommend darkening the bevel on a primary mirror for the above reasons.




Good reasons.

I propose then that those who want to do bevel darkening might try doing it by "bevel baffling":

Take a strip of black paper.
Using a straight edge bend on edge of the strip at a right angle to be the same width as the bevel.
Snip this bevel baffle every inch of so with scissors so that it can be wrapped around the mirror.
Wrap the paper around the mirror edge snugly using some double sided tape.

Will this interfere with mirror cooling?

No:
1) A single thickness of copy paper slows heat transport only as much as 0.07" of glass;
2) mirrors lose very little heat from their edges anyway - only that portion of glass that is closer to the edge than either the front or the back loses heat this way.

If you were still concerned with cooling you could use very thin metal instead (and this might be preferable for durability in humid environments anyway).


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GlennLeDrew
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Re: Blackening mirror edges? new [Re: careysub]
      #5712965 - 03/04/13 05:20 PM

A ground bevel scatters light almost isotropically. The bevel angle will not preferentially direct light toward the tube. Of course, the fact of the near uniform scatter makes that fraction directed into the FOV rather less than the overly pessimistic calculation I made earlier.

Nonetheless, if one is going all out with other baffling techniques, why not reduce scatter from all shiny, non image-forming surfaces?

I've used acrylic flat black paint to good effect. It's water resistant and does not seem to dissolve (readily, at least) in alcohol and such other solvents commonly used on glass coatings. I'm sure it can be removed without much shattering of nerves if re-coating is desired.


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precaud
Pooh-Bah
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Reged: 12/05/12

Loc: north central New Mexico
Re: Blackening mirror edges? new [Re: GlennLeDrew]
      #5714433 - 03/05/13 01:04 PM

+1 to Glenn's solution. I have a 2,000 sq ft warehouse whose roof I coated with white acrylic 5 years ago. I've been very impressed by its adhesion and how well it stands up to the elements. On that basis, I applied flat black acrylic with a cotton swab to blacken one of my primaries.

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Binojunky
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Re: Blackening mirror edges? new [Re: precaud]
      #5714629 - 03/05/13 02:51 PM

To be honest the improvement is so minor you would see the same result in observing with a clean eypiece compared to a dirty one, or a clean primary versus a dirty one, in other words barely noticable, if at all to the eye, another case of making a mountain out of a mole hill, JMPOV,DA.

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mark cowan
Vendor (Veritas Optics)
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Reged: 06/03/05

Loc: salem, OR
Re: Blackening mirror edges? new [Re: Binojunky]
      #5714858 - 03/05/13 04:43 PM

There's no good reason to blacken primary bevels, and plenty of reasons not to, including cleaning issues and recoating contamination. All paints can contaminate mirrors, if you even get organics (from fingerprints) distributed on the coating once with solvents, they don't come off again.

Under test on optical benches, the bevel of a mirror NEVER shows under light incident along the optical axis. Coating doesn't change the relationship between the polished surface and the bevel, as both end up with the same coating reflectivity. There is NO reason to expect ANY change in contrast transfer due to bevel blackening - the surface doesn't reflect coherent light and it scatters very much next to nothing towards the focus.

It's simply a bad idea all around.

Best,
Mark


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tag1260
scholastic sledgehammer
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Reged: 10/07/12

Loc: Ohio, USA
Re: Blackening mirror edges? new [Re: mark cowan]
      #5714865 - 03/05/13 04:47 PM

Thanks guys. I've been talked out of it!!! Long winter with LOTS of cloudy nights to ponder upgrades and improvements!!

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GlennLeDrew
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Re: Blackening mirror edges? new [Re: tag1260]
      #5715263 - 03/05/13 08:12 PM

Well, when I peer down an OTA and see a bright ring of scattered light (especially for what I consider abnormally wide bevels, or flats ground so as to be rid of turned edge), I want to be rid of it.

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GlennLeDrew
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Re: Blackening mirror edges? new [Re: GlennLeDrew]
      #5715744 - 03/06/13 01:47 AM

Here's another way to look at it. A 2mm wide bevel on a 10" mirror presents an area of nearly 1,600mm^2, equal to a square patch of 40X40mm. Remember, that's a scattering, (usually) aluminized surface. This would be equivalent to at least 50 shiny, exposed screw/bolt heads on the inner tube wall, down near the primary. Would any discriminating amateur (or pro) tolerate that? We go through almost tortuous measures to lessen the impact of scattering sources less injurious than this.

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dave brock
professor emeritus


Reged: 06/06/08

Loc: Hamilton, New Zealand
Re: Blackening mirror edges? new [Re: GlennLeDrew]
      #5715747 - 03/06/13 01:59 AM

The screw heads typically do not have a ground surface, are not angled away from the light path and definitely do not have to get realuminised one day.

Dave


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Jason D
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Reged: 10/21/06

Loc: California
Re: Blackening mirror edges? new [Re: GlennLeDrew]
      #5715753 - 03/06/13 02:13 AM Attachment (6 downloads)

Quote:

Here's another way to look at it. A 2mm wide bevel on a 10" mirror presents an area of nearly 1,600mm^2, equal to a square patch of 40X40mm. Remember, that's a scattering, (usually) aluminized surface. This would be equivalent to at least 50 shiny, exposed screw/bolt heads on the inner tube wall, down near the primary. Would any discriminating amateur (or pro) tolerate that? We go through almost tortuous measures to lessen the impact of scattering sources less injurious than this.




Glen, I have suggested to the OP to place a temporary front aperture mask to mask the bevel and check a shiny star with and without the mask to see if any difference can be observed at the eyepiece. If your 50 shiny screw heads claim has merits then the OP should see a difference. If a difference is observed then the OP has a choice of darkening the bevel or installing a permanent mask closer to the mirror as shown in the attachment.

Jason


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beatlejuice
Pooh-Bah
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Reged: 04/05/11

Loc: Hamilton, ON,Canada
Re: Blackening mirror edges? new [Re: Jason D]
      #5715799 - 03/06/13 03:29 AM

Sorry, off topic just for one question.
Jason, what is that mask made of? Looks like a wider version would make a good ring baffle.

Eric


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Jason D
Postmaster
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Reged: 10/21/06

Loc: California
Re: Blackening mirror edges? new [Re: beatlejuice]
      #5715811 - 03/06/13 03:50 AM

I cut a ring from MDF backboard material then wrapped it with flocking paper. I drilled holes matching existing mirror cell bolts to place it securely in place.

I used the mask with my old stock mirror to cover a mild TDE then I kept it with my premium mirror to redirect air flow across the mirror to reduce thermal boundary layer but I found out that the mask was creating too much turbulence and decided to remove it. Now my scope performs better without it.

Jason


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nevy
professor emeritus
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Reged: 02/07/12

Loc: UK
Re: Blackening mirror edges? new [Re: Jason D]
      #5715888 - 03/06/13 06:58 AM

Quote:

I cut a ring from MDF backboard material then wrapped it with flocking paper. I drilled holes matching existing mirror cell bolts to place it securely in place.

I used the mask with my old stock mirror to cover a mild TDE then I kept it with my premium mirror to redirect air flow across the mirror to reduce thermal boundary layer but I found out that the mask was creating too much turbulence and decided to remove it. Now my scope performs better without it.

Jason



Hello Jason , what do you mean by turbulence ? I was about to make one of them there rings for my 12" solid tube dob, would I be wasting my time & would I be better off just baffling the fan and leaving it at that?


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Jason D
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Re: Blackening mirror edges? new [Re: nevy]
      #5716232 - 03/06/13 11:44 AM

I will share my experience but let me clarify from the onset that I am not making any recommendation since I do not know how much of my experience and preference applies to other scopes.

In my case, I did install a fan baffle and the ring mask I have shown in the earlier post in this thread. I used this setup for a while but I have not been happy with it. When I did some analysis, here is what I noticed:

1- I noticed some air was escaping around the fan. I did my best to cut a baffle with an almost perfect fit but the pressure building between the mirror and the fan was too high and managed to push air through crevices between the baffle and the scope.

2- As far as the air that was redirected across the mirror by the ring mask, it was causing too much air turbulence above the mirror surface. I can see that clearly by defocusing a bright star. When the fan in turned on then the “boiling” effect got too severe.

I ended up removing the baffle and the ring – back to the original scope setup – and things got better. The turbulence was minimal when the fan was turned on.
These days I hardly use the fan but I live in California and nights temperature here is not too bad.

Jason


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Binojunky
Carpal Tunnel
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Reged: 12/25/10

Re: Blackening mirror edges? new [Re: Jason D]
      #5716280 - 03/06/13 12:13 PM

One thing worth remembering is that any time you remove and replace optics in a scope you run the chance of an accident resulting in damage, for what is a pointless upgrade(edge blackening) why take the risk?,DA.

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Sarkikos
Postmaster
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Reged: 12/18/07

Loc: Suburban Maryland, USA
Re: Blackening mirror edges? new [Re: Binojunky]
      #5716354 - 03/06/13 01:08 PM

I've never had an optics-damaging accident when removing, cleaning, etc. mirrors in my Newts. Never dropped an eyepiece. Never damaged a lens or mirror. You just need to be careful and aware of what you are doing and aware of your surroundings. No quick, hyper movements. Maybe cut back on the coffee beforehand. Enter a Zen-state of relaxed concentration.


Mike


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Sarkikos
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Re: Blackening mirror edges? new [Re: Jason D]
      #5716373 - 03/06/13 01:19 PM

Jason D,

Quote:

In my case, I did install a fan baffle and the ring mask I have shown in the earlier post in this thread. I used this setup for a while but I have not been happy with it. When I did some analysis, here is what I noticed:

1- I noticed some air was escaping around the fan. I did my best to cut a baffle with an almost perfect fit but the pressure building between the mirror and the fan was too high and managed to push air through crevices between the baffle and the scope.

2- As far as the air that was redirected across the mirror by the ring mask, it was causing too much air turbulence above the mirror surface. I can see that clearly by defocusing a bright star. When the fan in turned on then the “boiling” effect got too severe.

I ended up removing the baffle and the ring – back to the original scope setup – and things got better. The turbulence was minimal when the fan was turned on.




I did something similar for my 8" f/6 Newt. At first, I attached a thin baffle under the mirror clips as you did. But I think this might be too close to the mirror, or as you experienced, will not allow a good seal. Maybe good to cover a TDE, but not so good for directing air currents. The effect was either neutral or a bit worse than without the baffle. (I have a fan suspended in a baffle below the primary, blowing air up against the bottom of the mirror.)

But then I constructed an annular baffle from black foam core and positioned it directly above the mirror clips. The baffle is snug tight against the inner wall of the OTA. This time I noticed a circular motion of the thermals in a defocused star or planet. At least I was having some effect on the image - the boiling effect was replaced by a circular motion - showing that the thermals were being moved differently than without the baffle.

Recently I drilled a line of several lateral holes just above the edge of the primary, below the baffle. Hopefully this will allow the thermals to escape more easily from the solid-tube OTA and improve the image.

Others have done similar things and gotten mixed results. I've yet to get a chance to retest the scope under good seeing. If it works out well, I might do the same thing for my 10" solid-tube Newt.

Of course, back on the topic of blackening mirror edges, an annular baffle would cover the bevel - and perhaps a TDE, if the baffle is wide enough - and negate any need for blackening the bevel.

Mike


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Jason D
Postmaster
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Reged: 10/21/06

Loc: California
Re: Blackening mirror edges? new [Re: Sarkikos]
      #5716473 - 03/06/13 02:01 PM

Quote:

But then I constructed an annular baffle from black foam core and positioned it directly above the mirror clips. The baffle is snug tight against the inner wall of the OTA.



Sounds like your solution placed the mask few millimeters higher than mine and sealed it against the OTA wall. I placed mine right above the clips.

Quote:

Recently I drilled a line of several lateral holes just above the edge of the primary, below the baffle. Hopefully this will allow the thermals to escape more easily from the solid-tube OTA and improve the image.



I am aware of this mod – including mounting in/out fans outside the holes – but I do not have the guts to mutilate my OTA yet.

Quote:

Of course, back on the topic of blackening mirror edges, an annular baffle would cover the bevel - and perhaps a TDE, if the baffle is wide enough - and negate any need for blackening the bevel.



Another important observation I noticed is the effect of the mask on the defocused star image. I felt the in-defocus star image showed a more scattered outer ring. After all, the mask edge is on the light path and will have some sort of a diffraction impact. The in-defocused star image improved after removing it. Of course, if someone has a TDE problem then the mask will be an improvement but when used with premium optics I believe the mask will make it worse. This is based on my observation and I am not generalizing it.
Bottom line, I believe the baffle and mask positive/negative impact depends on the scope, optics, and the local weather. Results could vary.

Jason


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nevy
professor emeritus
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Reged: 02/07/12

Loc: UK
Re: Blackening mirror edges? new [Re: Jason D]
      #5716755 - 03/06/13 04:17 PM

Thanks Jason , that's very helpfull as usuall
Staying on the subject of blackening the bevel , I haven't done mine and don't intend too but I have painted the secondary back & sides with blackboard paint.


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Jason D
Postmaster
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Reged: 10/21/06

Loc: California
Re: Blackening mirror edges? new [Re: nevy]
      #5717037 - 03/06/13 06:44 PM

In my case, I applied a piece of a flocking paper to cover the edge of my secondary mirror visible from the focuser as shown below. When I made the cut, I left two notches for the safety string.


You can see how “blackish” the flocking paper as seen from the focuser in the following photo:


I cut a perfect fit, I did the math as shown below:


Jason


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Sarkikos
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Loc: Suburban Maryland, USA
Re: Blackening mirror edges? new [Re: Jason D]
      #5717278 - 03/06/13 09:05 PM

My secondaries are in housings. I flocked the entire outer surface of the housings with ProtoStar. I didn't bother with math to figure it out. I just measured carefully and cut to shape. Fits perfectly.

I flock or paint virtually every surface inside the OTA except the optical surfaces.

Mike


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Binojunky
Carpal Tunnel
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Reged: 12/25/10

Re: Blackening mirror edges? new [Re: Sarkikos]
      #5718108 - 03/07/13 10:43 AM

Quote:

I've never had an optics-damaging accident when removing, cleaning, etc. mirrors in my Newts. Never dropped an eyepiece. Never damaged a lens or mirror. You just need to be careful and aware of what you are doing and aware of your surroundings. No quick, hyper movements. Maybe cut back on the coffee beforehand. Enter a Zen-state of relaxed concentration.


Mike



That reminds me of the driver who.s never had an accident or the gambler who always claims he wins and never loses,having more than once seen mirrors damaged from removal, it happens, simple as that, cleaning a mirror is a neccesary evil because dirt over time can effect performance however removing optics to blacken edges is a risk that can be avoided,DA.


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Sarkikos
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Re: Blackening mirror edges? new [Re: Binojunky]
      #5718187 - 03/07/13 11:15 AM

Gambling isn't a good analogy to driving, and driving isn't a good analogy to cleaning telescope mirrors. Among these situations, we have more and more control over the variables involved. In gambling, the outcome is mostly a matter of chance. In driving, we have more control over the outcome, but we cannot control the weather or the other drivers. For cleaning telescope mirrors or blackening mirror edges, unless something out-of-the-ordinary occurs - such as an asteroid strike or the house blowing up - we are pretty much in control of the entire situation, beginning to end.

Mike


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Binojunky
Carpal Tunnel
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Reged: 12/25/10

Re: Blackening mirror edges? new [Re: Sarkikos]
      #5720775 - 03/08/13 04:09 PM

Quote:

Gambling isn't a good analogy to driving, and driving isn't a good analogy to cleaning telescope mirrors. Among these situations, we have more and more control over the variables involved. In gambling, the outcome is mostly a matter of chance. In driving, we have more control over the outcome, but we cannot control the weather or the other drivers. For cleaning telecope mirrors or blackening mirror edges, unless something out-of-the-ordinary occurs - such as an asteriod strike or the house blowing up - we are pretty much in control of the entire situation, beginning to end.

Mike




The end result in either is the same though, be it a damaged car, lost money, or a damaged mirror that could have been avoided, lots of cursing under ones breath and"why didn,t I leave well alone?",DA.


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Scanning4Comets
Markus
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Reged: 12/26/04

Loc: Ontario, Canada
Re: Blackening mirror edges? new [Re: Binojunky]
      #5720832 - 03/08/13 04:52 PM

Quote:

But then I constructed an annular baffle from black foam core and positioned it directly above the mirror clips. The baffle is snug tight against the inner wall of the OTA. This time I noticed a circular motion of the thermals in a de-focused star or planet. At least I was having some effect on the image - the boiling effect was replaced by a circular motion - showing that the thermals were being moved differently than without the baffle.




Mike,

I also had the same circular motion with AND without the baffle. Now I just leave the fan suspended on elastics. This way, if my batteries go kaput, I can at least have the mirror exposed to the air. I don't like the idea of having a bunch of extra D-Cell batteries lying around in case they sit too long and get wasted. Another good reason I have my fan on elastics and the mirror exposed is for a faster warm-up, when I get in the house.

Quote:

Gambling isn't a good analogy to driving, and driving isn't a good analogy to cleaning telescope mirrors. Among these situations, we have more and more control over the variables involved. In gambling, the outcome is mostly a matter of chance. In driving, we have more control over the outcome, but we cannot control the weather or the other drivers. For cleaning telecope mirrors or blackening mirror edges, unless something out-of-the-ordinary occurs - such as an asteriod strike or the house blowing up - we are pretty much in control of the entire situation, beginning to end.

Mike






Yes, but nobody is perfect and accidents DO happen, kinda like the spelling of the words "telescope" and "asteroid" in your last post.

Cheers,


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Sarkikos
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Reged: 12/18/07

Loc: Suburban Maryland, USA
Re: Blackening mirror edges? new [Re: Scanning4Comets]
      #5720875 - 03/08/13 05:22 PM

Seen and corrected. A little typo now and then is not equivalent to damaged optics. I'm much more careful when I clean my mirrors.


Mike


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Scanning4Comets
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Re: Blackening mirror edges? new [Re: Sarkikos]
      #5720950 - 03/08/13 06:11 PM

C'mon Mike, You're not perfect, and neither am I. I was just saying that accidents do happen. I am extra careful myself but once had a 12.5" mirror fall right out of my telescope tube because I had FORGOT to put the screws back in the bottom after an inspection. I had to use silicone adhesive to get it back onto my cell when it did happen.

I was thankful that it didn't break when it had hit the floor. I was nowhere near it when it happened.

Just sayin'

Cheers,


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Sarkikos
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Re: Blackening mirror edges? new [Re: Scanning4Comets]
      #5721352 - 03/08/13 10:55 PM

Nope, never had an optical accident. My typing could stand some improvement, however.

Mike


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Jason D
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Re: Blackening mirror edges? new [Re: Sarkikos]
      #5721374 - 03/08/13 11:21 PM

Why doesn’t everyone leave the decision whether to take the mirror out or not to scope owners!
Some are careful and some are clumsy. No one can generalize.


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Re: Blackening mirror edges? new [Re: Jason D]
      #5721470 - 03/09/13 12:52 AM

Sounds like a good idea to me.

Mike


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Binojunky
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Re: Blackening mirror edges? new [Re: Sarkikos]
      #5722310 - 03/09/13 01:13 PM

Agreed ,DA.

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FineArt
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Re: Blackening mirror edges? new [Re: Sarkikos]
      #5722408 - 03/09/13 02:05 PM

If you use black butyl caulking instead of paint, you can peel it off when it comes time to re-coat the mirror.

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Re: Blackening mirror edges? new [Re: FineArt]
      #5722416 - 03/09/13 02:15 PM

I'll have to check into that.

Mike


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