The Mirror Lens Club!

**goatsNdonkey** · 12-28-2016, 07:54 AM

Originally posted by channeler

I have been on the edge of buying an M42 extension tube set Tim, The smallest tube in the set I came across was about 11mm. I'm not sure that it would give enough clearance to mount the lens and from everything I have read recently any tube seems to drastically affect infinity focus. I may still take the plunge just to give it a shot. Another member in an old post talked about stacking 20mm of tubes to use the Rubinar on his K20D. I don't know what he did about infinity focus, but I am trying to contact him about his experience. Another option is to try it with my tamron 1.4x TC (using the M42 adapter on the TC rather than the camera body) which may still maintain infinity focus? I may give that a shot later today.

I am going to have to make a decision soon as to whether to keep persevering to try to find a solution or to contact the Ebay seller that I purchased it from to see about returning it.

Paul

There are very, very cheap manual K-mount extension tube sets available on the auction website, the kind that have a front mount ring, a back mount ring, and 3 spacers of different lengths that can be used between, alone or in combination. With the set of them I have, using the two mount rings alone, I measure the extension as 11 millimeters. When the skinniest spacer is added between them, I measure the extension at about 18.5mm. If the lens is M42 mount you'd need to insert an adapter in the lens mount end of this extension set up. Obviously, the other end of the tube assembly would mount fine in a Pentax dslr. It would be a cheap way to try extension with this mirror lens.

Last edited by goatsNdonkey; 12-28-2016 at 07:59 AM.

tim60 · 12-28-2016, 11:29 AM

Would one of the cheap K to M42 adapters that prevents infinity focus give enough extension?

channeler · 12-29-2016, 10:07 AM

I don't think the adapters that prevent infinity focus would give enough extension on their own Tim. I think it would need some use of extension tube/tubes in the way goatsNdonkey was suggesting. The overhang of the flash housing on my K-30 is significant. Some regrets but I've decided to call it a day with the Rubinar. If I had had all the bits and pieces to hand to experiment I may have found a solution. I got to the point where I needed to make a decision re contacting the seller about a return or not. I have had an email from a member saying he found a way to create a 13mm spacer which enabled him to clear the flash housing of his K20D and he managed to retain infinity focusing. I don't know though which version of the Rubinar he has. Thanks for everyone's help and advice and hopefully others may find the posts useful if they are considering a Rubinar. For the moment I think I will be looking to experimenting with a Tamron 500mm F8. Perhaps I will revisit the 1000mm mirrors sometime in the future.

Paul

mlynch53 · 01-09-2017, 08:31 PM - **1 Like**

After having read through this forum over the last few weeks, I decided to start adding photos I've taken with a recently acquired Sigma 600mm f/8 mirror lens for my Pentax K-r. I bought the lens with the aim of using it for the August total eclipse of the Sun.

I've spent some time taking experimental shots, including (of course!) some shots of the Moon. I'm getting more and more comfortable with the lens and taking better shots with it. I really like the lens and I've come to terms with its limitations; I think it should work well for eclipse shot as well as some more static terrestrial shots, as well, perhaps including bird shots in the fields behind our house, which have a variety of wild birds....

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Horus28 · 01-11-2017, 12:17 AM

Hi this might seem like a stupid question to many but I don't want to go to a lens dealer and ask. I have a K - r and a RMC Tokina 500 mm mirror lens. I can use it but to do so I have to manually set my camera to recognise that it is f/8 and then I can proceed. It would seem this is straightforward enough but I forget. I bought it secondhand sometime ago will modern mirror lens tell my camera that it is a F/8 automatically.

mlynch53 · 01-11-2017, 05:55 AM

No stupid questions...!

My experience with that very lens and my K-r is that when I turn the camera on, the display wants to know the focal length, which I then set. If I have the K-r set on aperture priority, it seems to auto-detect the f/8, and it will take appropriate photos. That's my recollection, because once I bought the 600mm f/8 Sigma, I haven't used the 500mm in a while. In fact, I have it for sale online.

I hope this helps.

**goatsNdonkey** · 01-11-2017, 07:19 AM - **1 Like**

Originally posted by Horus28

Hi this might seem like a stupid question to many but I don't want to go to a lens dealer and ask. I have a K - r and a RMC Tokina 500 mm mirror lens. I can use it but to do so I have to manually set my camera to recognise that it is f/8 and then I can proceed. It would seem this is straightforward enough but I forget. I bought it secondhand sometime ago will modern mirror lens tell my camera that it is a F/8 automatically.

For repeated photographer-forgetfulness errors, I tape a note on the camera. It prevents swearing at myself in public.

**marcusBMG** · 01-11-2017, 08:01 AM

Originally posted by Horus28

Hi this might seem like a stupid question to many but I don't want to go to a lens dealer and ask. I have a K - r and a RMC Tokina 500 mm mirror lens. I can use it but to do so I have to manually set my camera to recognise that it is f/8 and then I can proceed. It would seem this is straightforward enough but I forget. I bought it secondhand sometime ago will modern mirror lens tell my camera that it is a F/8 automatically.

Mirror lenses are easy in that sense - there is no changing the aperture or aperture linkages. Av aperture priority is mode of choice. The camera won't display or record any f number but that doesn't matter. Av works with all lenses actually, the issue is that with "M" and "K" series lenses ie K mount lenses without contacts, the camera won't stop down, you are restricted to wide open only.
The more problematical part with mirrors is focusing...

OftheManor · 01-11-2017, 11:38 AM

Does anyone have or know where one is of this lens.
I have one but the part that couples to the camera appears to be missing.
There is a recess with three set screwsthat I believe receives something like a T-mount adapter. My understanding is that Sigma had a lens adapter system which was proprietary.
I would be looking for a photo or two of the adapter and a few measurements. Not necessarily Pentax as I will be using the lens with a Sony E mount that I have adapters for several systems.
If this Sigma mount is familiar to you and you have another lens that uses it the info would be just as welcome.
Thanks in advance

500 f8

**goatsNdonkey** · 01-11-2017, 12:48 PM

Early on, there were Sigmas or Sigma-made mirror lenses that used the original T-mount. My Sigma-made Spiratone f8 500mm Ultra-tel is one of them. That doesn't mean that Sigma didn't later have a proprietary interchangeable mount system on certain lenses. As I suspect you know, the T-mount thread uses the same diameter as the old Pentax/Universal m42 scew mount that fit many brands of cameras at one time -- EXCEPT the T-mount threads are a different pitch. If the mount end of your lens has the same diameter as an m42 camera mount, it might be a T-mount. Since a mirror lens only has one aperture, there really isn't anything to "couple" to the camera, exposure system wise. It's just a matter of attaching the lens the correct way.

Horus28 · 01-11-2017, 03:36 PM

thanks just tried it certainly works.

OftheManor · 01-11-2017, 05:54 PM

Originally posted by goatsNdonkey

Early on, there were Sigmas or Sigma-made mirror lenses that used the original T-mount. My Sigma-made Spiratone f8 500mm Ultra-tel is one of them. That doesn't mean that Sigma didn't later have a proprietary interchangeable mount system on certain lenses. As I suspect you know, the T-mount thread uses the same diameter as the old Pentax/Universal m42 scew mount that fit many brands of cameras at one time -- EXCEPT the T-mount threads are a different pitch. If the mount end of your lens has the same diameter as an m42 camera mount, it might be a T-mount. Since a mirror lens only has one aperture, there really isn't anything to "couple" to the camera, exposure system wise. It's just a matter of attaching the lens the correct way.

Thanks for your thoughts on my problem. The lens' camera end is a female unthreaded bore with three set screws. I imagine the lens adapter has a groove that the three sets screws use to lock the lens longtitdunally while a larger single screw with a knurled knob is used to prevent rotation or allow spinning the camera between portrait and landscape modes.
I can probably guesstimate and prototype but was hoping there was someone with a copy of this lens to hand.

cooltouch · 01-12-2017, 03:37 AM

Without seeing what you're describing, it sounds to me like you're describing the inner ring of a T-mount. If you have a T-mount adapter handy, take a look at it. I'm pretty sure they're all made similarly, although there may be an exception, like M42. Anyway, take a look at your T-mount adapter. face on. You should see that it is two pieces, and these two pieces are held in place by three set screws located along the edge of the adapter. The reason for them is so you can center the T-mount on your camera so the lens will be in a face-up orientation. If you remove these three set screws, and then separate the two rings, you'll see that the inner ring has a pronounced groove that the screws fit down into. So, if I'm right about this, what you have on your lens is just 1/2 of a T-mount adapter. Unscrew it and mount a complete one and you should be on your way.

If this isn't the case, then please let us know.

---------- Post added 01-12-17 at 05:02 AM ----------

Originally posted by mlynch53

After having read through this forum over the last few weeks, I decided to start adding photos I've taken with a recently acquired Sigma 600mm f/8 mirror lens for my Pentax K-r. I bought the lens with the aim of using it for the August total eclipse of the Sun.

I've spent some time taking experimental shots, including (of course!) some shots of the Moon. I'm getting more and more comfortable with the lens and taking better shots with it. I really like the lens and I've come to terms with its limitations; I think it should work well for eclipse shot as well as some more static terrestrial shots, as well, perhaps including bird shots in the fields behind our house, which have a variety of wild birds....

The Sigma 600mm f/8 can be an incredibly sharp optic or just an okay one. I know because I've had both. Back in about 1984 I bought one in Canon FD mount. It was so long that it took me a while before I was any good shooting with it, but as I became better with my technique, I got some awesome pics with it. I foolishly sold it when I temporarily changed systems to Nikon. Back then, my best shots came from using a stout tripod and cameras with mirror lock-up.

Well, I never forgot how good that lens was and then a couple years ago, I came across a great deal on one in EOS mount, which is fairly uncommon. I just assumed that Sigma quality control was such that all 600/8 mirrors were the same optically. Unfortunately, I was in for a big disappointment. The one I currently own is "just okay." Judging from your second shot, I'd say you got a good one. It's hard to see much detail in your moon shot.

A word about the solar eclipse -- I've been through one that was almost total -- back in about 1991, I guess it was. And I was savvy enough about astronomy and astrophotography to know what should and shouldn't be done when taking pics of a solar eclipse.

First, keep in mind you're taking pics of the sun, and even when total the coronosphere is still very bright. So what you will need to get for your lens is a solar filter that you can fit over it. Now, there are expensive solar filters and there are cheap ones, but they all do basically the same job -- filtering out enough of the sun's rays so your eyes won't be damaged. I bought a solar filter for the eclipse I witnessed, but I decided just to buy a cheap one. I think I may have paid about $20 for it. What it ended up being was just a mirrored mylar disk in a round plastic frame. Mine was about 5 inches in diameter. When it came time to observe the eclipse, I just taped it to the front of a small 4 inch (about 600mm) scope I had, and this was perfect for viewing the eclipse. I suspect a cheap filter like this would even work OK for photography. Or you can go the expensive route and pay a couple hundred bucks if you feel so inclined.

I just checked eBay -- it might be a good source for you, whether you're looking for a cheap one or an expensive one.

Of course, if you already know all this, well then, never mind.

**goatsNdonkey** · 01-12-2017, 06:31 AM

I was thinking last night that OftheManor was describing half a t-mount, but I was going to check the one I had before saying anything. Good thing cooltouch jumped in.

mlynch53 · 01-12-2017, 07:23 PM

Quote:

A word about the solar eclipse -- I've been through one that was almost total -- back in about 1991, I guess it was. And I was savvy enough about astronomy and astrophotography to know what should and shouldn't be done when taking pics of a solar eclipse.

First, keep in mind you're taking pics of the sun, and even when total the coronosphere is still very bright. So what you will need to get for your lens is a solar filter that you can fit over it. Now, there are expensive solar filters and there are cheap ones, but they all do basically the same job -- filtering out enough of the sun's rays so your eyes won't be damaged. I bought a solar filter for the eclipse I witnessed, but I decided just to buy a cheap one. I think I may have paid about $20 for it. What it ended up being was just a mirrored mylar disk in a round plastic frame. Mine was about 5 inches in diameter. When it came time to observe the eclipse, I just taped it to the front of a small 4 inch (about 600mm) scope I had, and this was perfect for viewing the eclipse. I suspect a cheap filter like this would even work OK for photography. Or you can go the expensive route and pay a couple hundred bucks if you feel so inclined.

I just checked eBay -- it might be a good source for you, whether you're looking for a cheap one or an expensive one.

Of course, if you already know all this, well then, never mind.

Thanks, Michael!

Yeah, I've been an avid amateur astronomer for a long time,

and I have two filters I'm trying... One is made with Baader solar filter material, and the other is the Seymour solar filter. I'm planning to experiment with both of them in the coming months to find out which will do a better job...

I'm hoping we'll have a few sunspots of enough size to show up in photos during the eclipse....Otherwise, it will be a pretty blank (maybe even bland?) sun being eclipsed by the moon....at least until totality!

01-11-2017, 11:38 AM	#879
OftheManor Senior Member Join Date: May 2011 Location: BC Lower Mainland Posts: 118	Sigma-QX Mirror Ultra-telephoto Does anyone have or know where one is of this lens. I have one but the part that couples to the camera appears to be missing. There is a recess with three set screwsthat I believe receives something like a T-mount adapter. My understanding is that Sigma had a lens adapter system which was proprietary. I would be looking for a photo or two of the adapter and a few measurements. Not necessarily Pentax as I will be using the lens with a Sony E mount that I have adapters for several systems. If this Sigma mount is familiar to you and you have another lens that uses it the info would be just as welcome. Thanks in advance 500 f8 Last edited by OftheManor; 01-11-2017 at 11:39 AM. Reason: Added lens spec

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12-28-2016, 07:54 AM	#871
goatsNdonkey Site Supporter Join Date: Jan 2016 Location: Fulton County, Illinois Posts: 3,727	Originally posted by channeler I have been on the edge of buying an M42 extension tube set Tim, The smallest tube in the set I came across was about 11mm. I'm not sure that it would give enough clearance to mount the lens and from everything I have read recently any tube seems to drastically affect infinity focus. I may still take the plunge just to give it a shot. Another member in an old post talked about stacking 20mm of tubes to use the Rubinar on his K20D. I don't know what he did about infinity focus, but I am trying to contact him about his experience. Another option is to try it with my tamron 1.4x TC (using the M42 adapter on the TC rather than the camera body) which may still maintain infinity focus? I may give that a shot later today. I am going to have to make a decision soon as to whether to keep persevering to try to find a solution or to contact the Ebay seller that I purchased it from to see about returning it. Paul There are very, very cheap manual K-mount extension tube sets available on the auction website, the kind that have a front mount ring, a back mount ring, and 3 spacers of different lengths that can be used between, alone or in combination. With the set of them I have, using the two mount rings alone, I measure the extension as 11 millimeters. When the skinniest spacer is added between them, I measure the extension at about 18.5mm. If the lens is M42 mount you'd need to insert an adapter in the lens mount end of this extension set up. Obviously, the other end of the tube assembly would mount fine in a Pentax dslr. It would be a cheap way to try extension with this mirror lens. Last edited by goatsNdonkey; 12-28-2016 at 07:59 AM.

12-28-2016, 11:29 AM	#872
tim60 Pentaxian Join Date: Apr 2011 Photos: Albums Posts: 8,743	Would one of the cheap K to M42 adapters that prevents infinity focus give enough extension?

12-29-2016, 10:07 AM	#873
channeler Veteran Member Join Date: Jun 2007 Location: Northwich Cheshire England Photos: Gallery Posts: 1,009	I don't think the adapters that prevent infinity focus would give enough extension on their own Tim. I think it would need some use of extension tube/tubes in the way goatsNdonkey was suggesting. The overhang of the flash housing on my K-30 is significant. Some regrets but I've decided to call it a day with the Rubinar. If I had had all the bits and pieces to hand to experiment I may have found a solution. I got to the point where I needed to make a decision re contacting the seller about a return or not. I have had an email from a member saying he found a way to create a 13mm spacer which enabled him to clear the flash housing of his K20D and he managed to retain infinity focusing. I don't know though which version of the Rubinar he has. Thanks for everyone's help and advice and hopefully others may find the posts useful if they are considering a Rubinar. For the moment I think I will be looking to experimenting with a Tamron 500mm F8. Perhaps I will revisit the 1000mm mirrors sometime in the future. Paul

01-11-2017, 12:17 AM	#875
Horus28 New Member Join Date: Aug 2011 Location: Canberra Posts: 13	Hi this might seem like a stupid question to many but I don't want to go to a lens dealer and ask. I have a K - r and a RMC Tokina 500 mm mirror lens. I can use it but to do so I have to manually set my camera to recognise that it is f/8 and then I can proceed. It would seem this is straightforward enough but I forget. I bought it secondhand sometime ago will modern mirror lens tell my camera that it is a F/8 automatically.

01-11-2017, 05:55 AM	#876
mlynch53 Forum Member Join Date: Dec 2010 Location: Kentucky Posts: 95	No stupid questions...! My experience with that very lens and my K-r is that when I turn the camera on, the display wants to know the focal length, which I then set. If I have the K-r set on aperture priority, it seems to auto-detect the f/8, and it will take appropriate photos. That's my recollection, because once I bought the 600mm f/8 Sigma, I haven't used the 500mm in a while. In fact, I have it for sale online. I hope this helps.

01-11-2017, 07:19 AM - 1 Like	#877
goatsNdonkey Site Supporter Join Date: Jan 2016 Location: Fulton County, Illinois Posts: 3,727	Originally posted by Horus28 Hi this might seem like a stupid question to many but I don't want to go to a lens dealer and ask. I have a K - r and a RMC Tokina 500 mm mirror lens. I can use it but to do so I have to manually set my camera to recognise that it is f/8 and then I can proceed. It would seem this is straightforward enough but I forget. I bought it secondhand sometime ago will modern mirror lens tell my camera that it is a F/8 automatically. For repeated photographer-forgetfulness errors, I tape a note on the camera. It prevents swearing at myself in public.

01-11-2017, 08:01 AM	#878
marcusBMG Site Supporter Join Date: Nov 2012 Location: North Wales Photos: Gallery \| Albums Posts: 2,869	Originally posted by Horus28 Hi this might seem like a stupid question to many but I don't want to go to a lens dealer and ask. I have a K - r and a RMC Tokina 500 mm mirror lens. I can use it but to do so I have to manually set my camera to recognise that it is f/8 and then I can proceed. It would seem this is straightforward enough but I forget. I bought it secondhand sometime ago will modern mirror lens tell my camera that it is a F/8 automatically. Mirror lenses are easy in that sense - there is no changing the aperture or aperture linkages. Av aperture priority is mode of choice. The camera won't display or record any f number but that doesn't matter. Av works with all lenses actually, the issue is that with "M" and "K" series lenses ie K mount lenses without contacts, the camera won't stop down, you are restricted to wide open only. The more problematical part with mirrors is focusing...

01-11-2017, 12:48 PM	#880
goatsNdonkey Site Supporter Join Date: Jan 2016 Location: Fulton County, Illinois Posts: 3,727	Early on, there were Sigmas or Sigma-made mirror lenses that used the original T-mount. My Sigma-made Spiratone f8 500mm Ultra-tel is one of them. That doesn't mean that Sigma didn't later have a proprietary interchangeable mount system on certain lenses. As I suspect you know, the T-mount thread uses the same diameter as the old Pentax/Universal m42 scew mount that fit many brands of cameras at one time -- EXCEPT the T-mount threads are a different pitch. If the mount end of your lens has the same diameter as an m42 camera mount, it might be a T-mount. Since a mirror lens only has one aperture, there really isn't anything to "couple" to the camera, exposure system wise. It's just a matter of attaching the lens the correct way.

01-11-2017, 03:36 PM	#881
Horus28 New Member Join Date: Aug 2011 Location: Canberra Posts: 13	thanks just tried it certainly works.

01-11-2017, 05:54 PM	#882
OftheManor Senior Member Join Date: May 2011 Location: BC Lower Mainland Posts: 118	Originally posted by goatsNdonkey Early on, there were Sigmas or Sigma-made mirror lenses that used the original T-mount. My Sigma-made Spiratone f8 500mm Ultra-tel is one of them. That doesn't mean that Sigma didn't later have a proprietary interchangeable mount system on certain lenses. As I suspect you know, the T-mount thread uses the same diameter as the old Pentax/Universal m42 scew mount that fit many brands of cameras at one time -- EXCEPT the T-mount threads are a different pitch. If the mount end of your lens has the same diameter as an m42 camera mount, it might be a T-mount. Since a mirror lens only has one aperture, there really isn't anything to "couple" to the camera, exposure system wise. It's just a matter of attaching the lens the correct way. Thanks for your thoughts on my problem. The lens' camera end is a female unthreaded bore with three set screws. I imagine the lens adapter has a groove that the three sets screws use to lock the lens longtitdunally while a larger single screw with a knurled knob is used to prevent rotation or allow spinning the camera between portrait and landscape modes. I can probably guesstimate and prototype but was hoping there was someone with a copy of this lens to hand.

01-12-2017, 03:37 AM	#883
cooltouch Veteran Member Join Date: Jan 2011 Location: Houston, Texas Photos: Gallery \| Albums Posts: 982	Without seeing what you're describing, it sounds to me like you're describing the inner ring of a T-mount. If you have a T-mount adapter handy, take a look at it. I'm pretty sure they're all made similarly, although there may be an exception, like M42. Anyway, take a look at your T-mount adapter. face on. You should see that it is two pieces, and these two pieces are held in place by three set screws located along the edge of the adapter. The reason for them is so you can center the T-mount on your camera so the lens will be in a face-up orientation. If you remove these three set screws, and then separate the two rings, you'll see that the inner ring has a pronounced groove that the screws fit down into. So, if I'm right about this, what you have on your lens is just 1/2 of a T-mount adapter. Unscrew it and mount a complete one and you should be on your way. If this isn't the case, then please let us know. ---------- Post added 01-12-17 at 05:02 AM ---------- Originally posted by mlynch53 After having read through this forum over the last few weeks, I decided to start adding photos I've taken with a recently acquired Sigma 600mm f/8 mirror lens for my Pentax K-r. I bought the lens with the aim of using it for the August total eclipse of the Sun. I've spent some time taking experimental shots, including (of course!) some shots of the Moon. I'm getting more and more comfortable with the lens and taking better shots with it. I really like the lens and I've come to terms with its limitations; I think it should work well for eclipse shot as well as some more static terrestrial shots, as well, perhaps including bird shots in the fields behind our house, which have a variety of wild birds.... The Sigma 600mm f/8 can be an incredibly sharp optic or just an okay one. I know because I've had both. Back in about 1984 I bought one in Canon FD mount. It was so long that it took me a while before I was any good shooting with it, but as I became better with my technique, I got some awesome pics with it. I foolishly sold it when I temporarily changed systems to Nikon. Back then, my best shots came from using a stout tripod and cameras with mirror lock-up. Well, I never forgot how good that lens was and then a couple years ago, I came across a great deal on one in EOS mount, which is fairly uncommon. I just assumed that Sigma quality control was such that all 600/8 mirrors were the same optically. Unfortunately, I was in for a big disappointment. The one I currently own is "just okay." Judging from your second shot, I'd say you got a good one. It's hard to see much detail in your moon shot. A word about the solar eclipse -- I've been through one that was almost total -- back in about 1991, I guess it was. And I was savvy enough about astronomy and astrophotography to know what should and shouldn't be done when taking pics of a solar eclipse. First, keep in mind you're taking pics of the sun, and even when total the coronosphere is still very bright. So what you will need to get for your lens is a solar filter that you can fit over it. Now, there are expensive solar filters and there are cheap ones, but they all do basically the same job -- filtering out enough of the sun's rays so your eyes won't be damaged. I bought a solar filter for the eclipse I witnessed, but I decided just to buy a cheap one. I think I may have paid about $20 for it. What it ended up being was just a mirrored mylar disk in a round plastic frame. Mine was about 5 inches in diameter. When it came time to observe the eclipse, I just taped it to the front of a small 4 inch (about 600mm) scope I had, and this was perfect for viewing the eclipse. I suspect a cheap filter like this would even work OK for photography. Or you can go the expensive route and pay a couple hundred bucks if you feel so inclined. I just checked eBay -- it might be a good source for you, whether you're looking for a cheap one or an expensive one. Of course, if you already know all this, well then, never mind.

01-12-2017, 06:31 AM	#884
goatsNdonkey Site Supporter Join Date: Jan 2016 Location: Fulton County, Illinois Posts: 3,727	I was thinking last night that OftheManor was describing half a t-mount, but I was going to check the one I had before saying anything. Good thing cooltouch jumped in.

01-12-2017, 07:23 PM	#885
mlynch53 Forum Member Join Date: Dec 2010 Location: Kentucky Posts: 95	Quote: A word about the solar eclipse -- I've been through one that was almost total -- back in about 1991, I guess it was. And I was savvy enough about astronomy and astrophotography to know what should and shouldn't be done when taking pics of a solar eclipse. First, keep in mind you're taking pics of the sun, and even when total the coronosphere is still very bright. So what you will need to get for your lens is a solar filter that you can fit over it. Now, there are expensive solar filters and there are cheap ones, but they all do basically the same job -- filtering out enough of the sun's rays so your eyes won't be damaged. I bought a solar filter for the eclipse I witnessed, but I decided just to buy a cheap one. I think I may have paid about $20 for it. What it ended up being was just a mirrored mylar disk in a round plastic frame. Mine was about 5 inches in diameter. When it came time to observe the eclipse, I just taped it to the front of a small 4 inch (about 600mm) scope I had, and this was perfect for viewing the eclipse. I suspect a cheap filter like this would even work OK for photography. Or you can go the expensive route and pay a couple hundred bucks if you feel so inclined. I just checked eBay -- it might be a good source for you, whether you're looking for a cheap one or an expensive one. Of course, if you already know all this, well then, never mind. Thanks, Michael! Yeah, I've been an avid amateur astronomer for a long time, and I have two filters I'm trying... One is made with Baader solar filter material, and the other is the Seymour solar filter. I'm planning to experiment with both of them in the coming months to find out which will do a better job... I'm hoping we'll have a few sunspots of enough size to show up in photos during the eclipse....Otherwise, it will be a pretty blank (maybe even bland?) sun being eclipsed by the moon....at least until totality!