Why NASA don't use Canon

Started Aug 20, 2004 | Discussions
Bust New Member • Posts: 23
Why NASA don't use Canon
8

There have been a few threads over the years about what cameras NASA take into space and why. So when an opportunity arose, I had to take it:

I was doing a subcontracting job at NASA last week and I got speaking to a guy in Image Analysis. I told him I was most interested in the cameras being used for shuttle missions and on the ISS.

The guy told me they use Kodak and Nikon DSLRs and Nikkor lenses exclusively. When asked why they weren't using Canon DSLRs, he replied that they had been trialled, and the bodies didn't have any problems. The problem, he said, is that Canon use Fluorite lens elements in many of their long lenses and that in trials the fluorite elements had suffered fractures from the vibration associated with a launch. On one occasion, a fluorite element had completely disintegrated rendering the lens useless. ED elements did not suffer any fracturing problems. He went on to say that Canon had been trying for years to get into the space program, but that NASA would never consider Canon cameras or lenses while they continued to employ Fluorite in any required lenses.

A quick google check also revealed more info about the downsides of fluorite lens elements:

Cracking due to shock and rapid changes in temperature:
http://alice.as.arizona.edu/~rogerc/chapters/Chapter%204a.html

Fragile, soft, degrades with moisture, cannot be hot-coated leading to coating failure:
http://www.questar-corp.com/QuestarPDF/Choosing.pdf

Using air-in-a-can to clean can cause fluorite lens to crack:
http://www.company7.com/library/clean.html

And, here's Nikon's spin in a recent press release, talking about their new SuperED glass: "....While the optical properties of this new glass closely resemble those of fluorite, Super ED glass is more resilient to rapid temperature changes (thermal shock) and not as susceptible to cracking as the crystal structure of fluorite. Super ED glass also boasts a higher refractive index than fluorite, making it highly capable of correcting aberrations other than chromatic aberration....."

Anyone here had their fluorite lens elements fracture? Or is this problem only common to extremes such as those associated with space missions?

Steven Noyes Forum Pro • Posts: 12,373
That is odd because...
4

On a Discovery special n the ISS, there was a distinctive Canon White lens attached to a camera body. So they are in use at some level.

But to answer you question, no. My Fluorite lenses are still in perfect shape.

Steven

T3 Forum Pro • Posts: 21,492
Re: Why NASA don't use Canon
6

Not likely. If human bones and delicate experiments can survive the stress of a shuttle launch, fluorite elements housed inside lens bodies certainly can.

The most likely reason is that Nasa started using Nikon decades ago (before the existence of the Canon EOS system, which wasn't even introduced until the late 80's), and that's what they've stuck to since then. Simple as that. And for a goverment agency that still uses a space vehicle designed in the 70's, that makes sense.

Bust wrote:

There have been a few threads over the years about what cameras
NASA take into space and why. So when an opportunity arose, I had
to take it:

I was doing a subcontracting job at NASA last week and I got
speaking to a guy in Image Analysis. I told him I was most
interested in the cameras being used for shuttle missions and on
the ISS.

The guy told me they use Kodak and Nikon DSLRs and Nikkor lenses
exclusively. When asked why they weren't using Canon DSLRs, he
replied that they had been trialled, and the bodies didn't have any
problems. The problem, he said, is that Canon use Fluorite lens
elements in many of their long lenses and that in trials the
fluorite elements had suffered fractures from the vibration
associated with a launch. On one occasion, a fluorite element had
completely disintegrated rendering the lens useless. ED elements
did not suffer any fracturing problems. He went on to say that
Canon had been trying for years to get into the space program, but
that NASA would never consider Canon cameras or lenses while they
continued to employ Fluorite in any required lenses.

A quick google check also revealed more info about the downsides of
fluorite lens elements:

Cracking due to shock and rapid changes in temperature:
http://alice.as.arizona.edu/~rogerc/chapters/Chapter%204a.html

Fragile, soft, degrades with moisture, cannot be hot-coated leading
to coating failure:
http://www.questar-corp.com/QuestarPDF/Choosing.pdf

Using air-in-a-can to clean can cause fluorite lens to crack:
http://www.company7.com/library/clean.html

And, here's Nikon's spin in a recent press release, talking about
their new SuperED glass: "....While the optical properties of this
new glass closely resemble those of fluorite, Super ED glass is
more resilient to rapid temperature changes (thermal shock) and not
as susceptible to cracking as the crystal structure of fluorite.
Super ED glass also boasts a higher refractive index than fluorite,
making it highly capable of correcting aberrations other than
chromatic aberration....."

Anyone here had their fluorite lens elements fracture? Or is this
problem only common to extremes such as those associated with space
missions?

 T3's gear list:T3's gear list
Canon EOS 60D Olympus PEN E-PL3 Canon EOS M Fujifilm X-E1 Sony a6000 +17 more
Chatsphotogpilot Senior Member • Posts: 1,442
Agreed...
1

The space shuttles still have 80286s and 80386s as their computer systems. Old is gold, I guess.
Chatsphotogpilot, PP-ASEL
http://www.digital10d.com/chats
http://www.chatterjees.com/portfolio
http://www.chatterjees.com/aviator
chatspilot@yahoo.com
'Cleared to land runway three four left'

 Chatsphotogpilot's gear list:Chatsphotogpilot's gear list
Fujifilm FinePix X100 Canon EOS-1Ds Mark III Panasonic Lumix DMC-GF1 Leica M9 Canon EF 35mm F1.4L USM +16 more
OP Bust New Member • Posts: 23
Re: That is odd because...
1

Steven Noyes wrote:

On a Discovery special on the ISS, there was a distinctive Canon
White lens attached to a camera body. So they are in use at some
level.

I can only repeat what I was told. Perhaps it was a white Nikon lens, or a Hassy lens, or perhaps it was one of the Canon trials the guy was referring to.

This site backs up the no-Canon statement:
http://eol.jsc.nasa.gov/sseop/metadata/camera.htm

It lists all cameras used in shuttle/ISS missions and the only digitals (or 35mm) are Nikon and Kodak. (old ones at that!)

But to answer you question, no. My Fluorite lenses are still in
perfect shape.

Good to hear.

Steven

KTanaka Regular Member • Posts: 289
Re: Why NASA don't use Canon

I dunno. It seems to me that the amount of thermo-mechanical stresses that would destroy a flourite element would also kill or at least incapacitate an astronaut. It also seems that we don't often hear about flourite elements shattering in the course of professional usage, which would arguably present some very physically stressful situations for these lenses.

So I think that this -may- be a bit of mythology in NASA and suspect that the "first adopted / not revisited" story may be closer to the core.

Peripherally, it's noteworthy that Canon's XL1 video camera was, and may still be, a standard video camera used onboard Shuttles. The story here, according to Canon video folks, is that the XL1 has the best radio frequency emission shielding among its peers. I don't know about the back story but I have seen stills from the Shuttle showing the XL1 or XL1S aboard.

FM2 Regular Member • Posts: 430
No... Only 8086 and 8088 computers, not 286/386/386SX

no text.

nanook s Senior Member • Posts: 1,705
Re: DCS-460 in that list is EOS mount

All the stuff on that list were made before Canon had any in-house DSLR.

Bust wrote:

Steven Noyes wrote:

On a Discovery special on the ISS, there was a distinctive Canon
White lens attached to a camera body. So they are in use at some
level.

I can only repeat what I was told. Perhaps it was a white Nikon
lens, or a Hassy lens, or perhaps it was one of the Canon trials
the guy was referring to.

This site backs up the no-Canon statement:
http://eol.jsc.nasa.gov/sseop/metadata/camera.htm

It lists all cameras used in shuttle/ISS missions and the only
digitals (or 35mm) are Nikon and Kodak. (old ones at that!)

But to answer you question, no. My Fluorite lenses are still in
perfect shape.

Good to hear.

Steven

leofoto Forum Member • Posts: 87
Re: Why NASA don't use Canon
1

So I cant´t take my canons to my next holiday on the moon???

Bust wrote:

There have been a few threads over the years about what cameras
NASA take into space and why. So when an opportunity arose, I had
to take it:

I was doing a subcontracting job at NASA last week and I got
speaking to a guy in Image Analysis. I told him I was most
interested in the cameras being used for shuttle missions and on
the ISS.

The guy told me they use Kodak and Nikon DSLRs and Nikkor lenses
exclusively. When asked why they weren't using Canon DSLRs, he
replied that they had been trialled, and the bodies didn't have any
problems. The problem, he said, is that Canon use Fluorite lens
elements in many of their long lenses and that in trials the
fluorite elements had suffered fractures from the vibration
associated with a launch. On one occasion, a fluorite element had
completely disintegrated rendering the lens useless. ED elements
did not suffer any fracturing problems. He went on to say that
Canon had been trying for years to get into the space program, but
that NASA would never consider Canon cameras or lenses while they
continued to employ Fluorite in any required lenses.

A quick google check also revealed more info about the downsides of
fluorite lens elements:

Cracking due to shock and rapid changes in temperature:
http://alice.as.arizona.edu/~rogerc/chapters/Chapter%204a.html

Fragile, soft, degrades with moisture, cannot be hot-coated leading
to coating failure:
http://www.questar-corp.com/QuestarPDF/Choosing.pdf

Using air-in-a-can to clean can cause fluorite lens to crack:
http://www.company7.com/library/clean.html

And, here's Nikon's spin in a recent press release, talking about
their new SuperED glass: "....While the optical properties of this
new glass closely resemble those of fluorite, Super ED glass is
more resilient to rapid temperature changes (thermal shock) and not
as susceptible to cracking as the crystal structure of fluorite.
Super ED glass also boasts a higher refractive index than fluorite,
making it highly capable of correcting aberrations other than
chromatic aberration....."

Anyone here had their fluorite lens elements fracture? Or is this
problem only common to extremes such as those associated with space
missions?

OP Bust New Member • Posts: 23
No it isn't

The DCS-460 is a Nikon F-Mount camera based on the N90:
http://www.lonestardigital.com/first_generation_procameras.htm

This can also be seen by the Nikon branding on the camera housing.

The EOS-mount equiv to the DCS-460 was the DCS-EOS1, which is not used by NASA.

nanook s wrote:
All the stuff on that list were made before Canon had any in-house
DSLR.

Bust wrote:

Steven Noyes wrote:

On a Discovery special on the ISS, there was a distinctive Canon
White lens attached to a camera body. So they are in use at some
level.

I can only repeat what I was told. Perhaps it was a white Nikon
lens, or a Hassy lens, or perhaps it was one of the Canon trials
the guy was referring to.

This site backs up the no-Canon statement:
http://eol.jsc.nasa.gov/sseop/metadata/camera.htm

It lists all cameras used in shuttle/ISS missions and the only
digitals (or 35mm) are Nikon and Kodak. (old ones at that!)

But to answer you question, no. My Fluorite lenses are still in
perfect shape.

Good to hear.

Steven

nanook s Senior Member • Posts: 1,705
Re: No it isn't
2

Then the picture is quite complete, isn't it: NASA never had any Canon lenses. They basicly standardized on Nikon F mount from the beginning, and never strayed. Just like they never strayed from 8086 on the Shuttle control, only with a couple 386 laptops visible in the cabin well into the late 90's (i.e. lagging the commercial world by half a decade even for portable devices).

Bust wrote:
The DCS-460 is a Nikon F-Mount camera based on the N90:
http://www.lonestardigital.com/first_generation_procameras.htm

This can also be seen by the Nikon branding on the camera housing.

The EOS-mount equiv to the DCS-460 was the DCS-EOS1, which is not
used by NASA.

nanook s wrote:
All the stuff on that list were made before Canon had any in-house
DSLR.

Bust wrote:

Steven Noyes wrote:

On a Discovery special on the ISS, there was a distinctive Canon
White lens attached to a camera body. So they are in use at some
level.

I can only repeat what I was told. Perhaps it was a white Nikon
lens, or a Hassy lens, or perhaps it was one of the Canon trials
the guy was referring to.

This site backs up the no-Canon statement:
http://eol.jsc.nasa.gov/sseop/metadata/camera.htm

It lists all cameras used in shuttle/ISS missions and the only
digitals (or 35mm) are Nikon and Kodak. (old ones at that!)

But to answer you question, no. My Fluorite lenses are still in
perfect shape.

Good to hear.

Steven

Tommy Huynh Regular Member • Posts: 276
Re: Why NASA don't use Canon
3

That's funny, it's not the Image Analysis group that evaluates the handheld photo gear but the photo group in B15. I ought to know as I used to work there. The image analysis group focuses their efforts on just that, reviewing video and still footage captured during a mission. Particularly the footage that comes off the umbilical well motion picture cameras of the shuttle.

As of 2000 at least, there was no test that I know of evaluating Canon lenses and faulting the flourite elements and your post suggests the flourite rationale for not using Canon as being in place "for years". At that time, the use of Nikon was due to the history of using Nikon. EVERYTHING flown has to be flight certified, there were a slew of Nikon lenses already certified and there was no compelling reason to swap out the entire system for Canon (despite my attempts) because the flight certification process is extremely slow and expensive. In addition, there were the custom thermal blankets and accessories already developed for Nikon gear. Also, there has been a good working relationship already established with Nikon (worked with them on a project where we needed a "shaved down" F5 w/o the prism). Then you also have the astronauts that have already been trained using the Nikon system. There are many reasons why they stayed with Nikon, none that I know of are because of ruggedness of the lenses.

Bust wrote:

There have been a few threads over the years about what cameras
NASA take into space and why. So when an opportunity arose, I had
to take it:

I was doing a subcontracting job at NASA last week and I got
speaking to a guy in Image Analysis. I told him I was most
interested in the cameras being used for shuttle missions and on
the ISS.

The guy told me they use Kodak and Nikon DSLRs and Nikkor lenses
exclusively. When asked why they weren't using Canon DSLRs, he
replied that they had been trialled, and the bodies didn't have any
problems. The problem, he said, is that Canon use Fluorite lens
elements in many of their long lenses and that in trials the
fluorite elements had suffered fractures from the vibration
associated with a launch. On one occasion, a fluorite element had
completely disintegrated rendering the lens useless. ED elements
did not suffer any fracturing problems. He went on to say that
Canon had been trying for years to get into the space program, but
that NASA would never consider Canon cameras or lenses while they
continued to employ Fluorite in any required lenses.

A quick google check also revealed more info about the downsides of
fluorite lens elements:

Cracking due to shock and rapid changes in temperature:
http://alice.as.arizona.edu/~rogerc/chapters/Chapter%204a.html

Fragile, soft, degrades with moisture, cannot be hot-coated leading
to coating failure:
http://www.questar-corp.com/QuestarPDF/Choosing.pdf

Using air-in-a-can to clean can cause fluorite lens to crack:
http://www.company7.com/library/clean.html

And, here's Nikon's spin in a recent press release, talking about
their new SuperED glass: "....While the optical properties of this
new glass closely resemble those of fluorite, Super ED glass is
more resilient to rapid temperature changes (thermal shock) and not
as susceptible to cracking as the crystal structure of fluorite.
Super ED glass also boasts a higher refractive index than fluorite,
making it highly capable of correcting aberrations other than
chromatic aberration....."

Anyone here had their fluorite lens elements fracture? Or is this
problem only common to extremes such as those associated with space
missions?

-- hide signature --
Masterdeath Senior Member • Posts: 2,632
Re: Why NASA don't use Canon
2

All the cameras they use are OLD, very OLD models...

T3 wrote:
Not likely. If human bones and delicate experiments can survive
the stress of a shuttle launch, fluorite elements housed inside
lens bodies certainly can.

The most likely reason is that Nasa started using Nikon decades ago
(before the existence of the Canon EOS system, which wasn't even
introduced until the late 80's), and that's what they've stuck to
since then. Simple as that. And for a goverment agency that still
uses a space vehicle designed in the 70's, that makes sense.

Bust wrote:

There have been a few threads over the years about what cameras
NASA take into space and why. So when an opportunity arose, I had
to take it:

I was doing a subcontracting job at NASA last week and I got
speaking to a guy in Image Analysis. I told him I was most
interested in the cameras being used for shuttle missions and on
the ISS.

The guy told me they use Kodak and Nikon DSLRs and Nikkor lenses
exclusively. When asked why they weren't using Canon DSLRs, he
replied that they had been trialled, and the bodies didn't have any
problems. The problem, he said, is that Canon use Fluorite lens
elements in many of their long lenses and that in trials the
fluorite elements had suffered fractures from the vibration
associated with a launch. On one occasion, a fluorite element had
completely disintegrated rendering the lens useless. ED elements
did not suffer any fracturing problems. He went on to say that
Canon had been trying for years to get into the space program, but
that NASA would never consider Canon cameras or lenses while they
continued to employ Fluorite in any required lenses.

A quick google check also revealed more info about the downsides of
fluorite lens elements:

Cracking due to shock and rapid changes in temperature:
http://alice.as.arizona.edu/~rogerc/chapters/Chapter%204a.html

Fragile, soft, degrades with moisture, cannot be hot-coated leading
to coating failure:
http://www.questar-corp.com/QuestarPDF/Choosing.pdf

Using air-in-a-can to clean can cause fluorite lens to crack:
http://www.company7.com/library/clean.html

And, here's Nikon's spin in a recent press release, talking about
their new SuperED glass: "....While the optical properties of this
new glass closely resemble those of fluorite, Super ED glass is
more resilient to rapid temperature changes (thermal shock) and not
as susceptible to cracking as the crystal structure of fluorite.
Super ED glass also boasts a higher refractive index than fluorite,
making it highly capable of correcting aberrations other than
chromatic aberration....."

Anyone here had their fluorite lens elements fracture? Or is this
problem only common to extremes such as those associated with space
missions?

Stan Jirman Contributing Member • Posts: 956
Has been upgraded after Challenger

They upgraded the main computers during the downtime caused by Challenger. At the same time they added ABS and the drag chute to all shuttles. It's now the 286 processor.

  • Stan

Photo Travelogues: http://www.phototrek.org/
Equipment list is in the profile.

 Stan Jirman's gear list:Stan Jirman's gear list
Sony RX100 VII
Dixter Regular Member • Posts: 259
White Lens
1

Now we know why Canon paints the lens white....

to keep the temperature down and protecting the lens from heat
related damage

Nill Toulme Veteran Member • Posts: 8,149
I think it's really because...

...Kodak and Nikon are Halliburton subsidiaries, while Canon is not.

Nill
~~
http://www.toulme.net

Bust wrote:

There have been a few threads over the years about what cameras
NASA take into space and why. So when an opportunity arose, I had
to take it:

I was doing a subcontracting job at NASA last week and I got
speaking to a guy in Image Analysis. I told him I was most
interested in the cameras being used for shuttle missions and on
the ISS.

The guy told me they use Kodak and Nikon DSLRs and Nikkor lenses
exclusively. When asked why they weren't using Canon DSLRs, he
replied that they had been trialled, and the bodies didn't have any
problems. The problem, he said, is that Canon use Fluorite lens
elements in many of their long lenses and that in trials the
fluorite elements had suffered fractures from the vibration
associated with a launch. On one occasion, a fluorite element had
completely disintegrated rendering the lens useless. ED elements
did not suffer any fracturing problems. He went on to say that
Canon had been trying for years to get into the space program, but
that NASA would never consider Canon cameras or lenses while they
continued to employ Fluorite in any required lenses.

A quick google check also revealed more info about the downsides of
fluorite lens elements:

Cracking due to shock and rapid changes in temperature:
http://alice.as.arizona.edu/~rogerc/chapters/Chapter%204a.html

Fragile, soft, degrades with moisture, cannot be hot-coated leading
to coating failure:
http://www.questar-corp.com/QuestarPDF/Choosing.pdf

Using air-in-a-can to clean can cause fluorite lens to crack:
http://www.company7.com/library/clean.html

And, here's Nikon's spin in a recent press release, talking about
their new SuperED glass: "....While the optical properties of this
new glass closely resemble those of fluorite, Super ED glass is
more resilient to rapid temperature changes (thermal shock) and not
as susceptible to cracking as the crystal structure of fluorite.
Super ED glass also boasts a higher refractive index than fluorite,
making it highly capable of correcting aberrations other than
chromatic aberration....."

Anyone here had their fluorite lens elements fracture? Or is this
problem only common to extremes such as those associated with space
missions?

Chatsphotogpilot Senior Member • Posts: 1,442
Re: Has been upgraded after Challenger

That was my understanding.
Chatsphotogpilot, PP-ASEL
http://www.digital10d.com/chats
http://www.chatterjees.com/portfolio
http://www.chatterjees.com/aviator
chatspilot@yahoo.com
'Cleared to land runway three four left'

 Chatsphotogpilot's gear list:Chatsphotogpilot's gear list
Fujifilm FinePix X100 Canon EOS-1Ds Mark III Panasonic Lumix DMC-GF1 Leica M9 Canon EF 35mm F1.4L USM +16 more
Peter Gregg Veteran Member • Posts: 4,753
Re: Why NASA don't use Canon

Well I took my white Canon lens and threw it up in the air as high as I could get it, and when it landed back on the ground it didn't survive.

So NASA is right!

I'd like to try it with a Nikon lens to make sure but I don't have one around, anyone can let me have their Nikon lens so I can try it?

Peter Gregg

Bust wrote:

There have been a few threads over the years about what cameras
NASA take into space and why. So when an opportunity arose, I had
to take it:

I was doing a subcontracting job at NASA last week and I got
speaking to a guy in Image Analysis. I told him I was most
interested in the cameras being used for shuttle missions and on
the ISS.

The guy told me they use Kodak and Nikon DSLRs and Nikkor lenses
exclusively. When asked why they weren't using Canon DSLRs, he
replied that they had been trialled, and the bodies didn't have any
problems. The problem, he said, is that Canon use Fluorite lens
elements in many of their long lenses and that in trials the
fluorite elements had suffered fractures from the vibration
associated with a launch. On one occasion, a fluorite element had
completely disintegrated rendering the lens useless. ED elements
did not suffer any fracturing problems. He went on to say that
Canon had been trying for years to get into the space program, but
that NASA would never consider Canon cameras or lenses while they
continued to employ Fluorite in any required lenses.

A quick google check also revealed more info about the downsides of
fluorite lens elements:

Cracking due to shock and rapid changes in temperature:
http://alice.as.arizona.edu/~rogerc/chapters/Chapter%204a.html

Fragile, soft, degrades with moisture, cannot be hot-coated leading
to coating failure:
http://www.questar-corp.com/QuestarPDF/Choosing.pdf

Using air-in-a-can to clean can cause fluorite lens to crack:
http://www.company7.com/library/clean.html

And, here's Nikon's spin in a recent press release, talking about
their new SuperED glass: "....While the optical properties of this
new glass closely resemble those of fluorite, Super ED glass is
more resilient to rapid temperature changes (thermal shock) and not
as susceptible to cracking as the crystal structure of fluorite.
Super ED glass also boasts a higher refractive index than fluorite,
making it highly capable of correcting aberrations other than
chromatic aberration....."

Anyone here had their fluorite lens elements fracture? Or is this
problem only common to extremes such as those associated with space
missions?

-- hide signature --

Peter Gregg

 Peter Gregg's gear list:Peter Gregg's gear list
Nikon D800E Olympus E-M1 Panasonic Lumix DMC-GH4 Canon EOS 5D Mark IV Panasonic GH5
Frank from AZ Veteran Member • Posts: 4,507
Ooooh, what will I bring on my Mars vacation then??? NT

Bust wrote:

There have been a few threads over the years about what cameras
NASA take into space and why. So when an opportunity arose, I had
to take it:

I was doing a subcontracting job at NASA last week and I got
speaking to a guy in Image Analysis. I told him I was most
interested in the cameras being used for shuttle missions and on
the ISS.

The guy told me they use Kodak and Nikon DSLRs and Nikkor lenses
exclusively. When asked why they weren't using Canon DSLRs, he
replied that they had been trialled, and the bodies didn't have any
problems. The problem, he said, is that Canon use Fluorite lens
elements in many of their long lenses and that in trials the
fluorite elements had suffered fractures from the vibration
associated with a launch. On one occasion, a fluorite element had
completely disintegrated rendering the lens useless. ED elements
did not suffer any fracturing problems. He went on to say that
Canon had been trying for years to get into the space program, but
that NASA would never consider Canon cameras or lenses while they
continued to employ Fluorite in any required lenses.

A quick google check also revealed more info about the downsides of
fluorite lens elements:

Cracking due to shock and rapid changes in temperature:
http://alice.as.arizona.edu/~rogerc/chapters/Chapter%204a.html

Fragile, soft, degrades with moisture, cannot be hot-coated leading
to coating failure:
http://www.questar-corp.com/QuestarPDF/Choosing.pdf

Using air-in-a-can to clean can cause fluorite lens to crack:
http://www.company7.com/library/clean.html

And, here's Nikon's spin in a recent press release, talking about
their new SuperED glass: "....While the optical properties of this
new glass closely resemble those of fluorite, Super ED glass is
more resilient to rapid temperature changes (thermal shock) and not
as susceptible to cracking as the crystal structure of fluorite.
Super ED glass also boasts a higher refractive index than fluorite,
making it highly capable of correcting aberrations other than
chromatic aberration....."

Anyone here had their fluorite lens elements fracture? Or is this
problem only common to extremes such as those associated with space
missions?

-- hide signature --

Frank from Phoenix
Canon 1D Mk2, Minolta G500 and lots of typos
digital evolution: Nikon 990> OlyE20> Pentax *ist D> CanonMK2> ?????

Surfdog Senior Member • Posts: 1,080
what we used when I was an astronaut

No wait, I was an argonaut....sorry.

Keyboard shortcuts:
FForum MMy threads