mirror lens
Posted 12/02/2011 - 23:44
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Long story short -
It is a layout for making long lenses small and light. On the downside, there is usually a price to pay in terms of image quality, they tend to be fixed aperture ( usually F8 ) and some of them produce a weird doughnut bouqeh.
It is a layout for making long lenses small and light. On the downside, there is usually a price to pay in terms of image quality, they tend to be fixed aperture ( usually F8 ) and some of them produce a weird doughnut bouqeh.
Posted 12/02/2011 - 23:50
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Hi Jacqui,
Mirror lenses are long telephoto lenses that include two mirrors as well as lens elements. Light enters the front element and is reflected off a large, concave forward facing mirror at the rear of the lens that directs the lens to a small rear facing mirror at the front which, in turn, reflects light through the aperture. This reduces the physical length of the lens by about a third, as well as the size and weight, making it much easier to handle.
There are a couple of drawbacks however. First the aperture is usually (always?)fixed, for example 500mm f/8, so it cannot be stopped down and the bokeh is unusual so that out of focus highlights are actually rings.
The only challenge on K-x is getting the correct exposure but with a fixed aperture I think that should be pretty easy. Someone with a K-x and experience of using a mirror lens on it may be able to give you detailed instructions.
Regards,
Roy
Mirror lenses are long telephoto lenses that include two mirrors as well as lens elements. Light enters the front element and is reflected off a large, concave forward facing mirror at the rear of the lens that directs the lens to a small rear facing mirror at the front which, in turn, reflects light through the aperture. This reduces the physical length of the lens by about a third, as well as the size and weight, making it much easier to handle.
There are a couple of drawbacks however. First the aperture is usually (always?)fixed, for example 500mm f/8, so it cannot be stopped down and the bokeh is unusual so that out of focus highlights are actually rings.
The only challenge on K-x is getting the correct exposure but with a fixed aperture I think that should be pretty easy. Someone with a K-x and experience of using a mirror lens on it may be able to give you detailed instructions.
Regards,
Roy
My PPG link
K-3, K-5 + D-BG4 Grip, Pentax: FA 50 1.4, DA* 300, Sigma 70-200 2.8 Macro HSM II, Sigma 18-50 2.8 EX DC, Metz 58 AF-1
K-3, K-5 + D-BG4 Grip, Pentax: FA 50 1.4, DA* 300, Sigma 70-200 2.8 Macro HSM II, Sigma 18-50 2.8 EX DC, Metz 58 AF-1
Posted 13/02/2011 - 00:04
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It would probably work best if you set the camera to Av mode and use an ISO which gives sensible shutter speeds (1/500 or better is the usual guide for a 500mm lens).
They do have limitations, the f8 ones will be very dark and tricky to focus while the f5.6 ones are likely to have very shallow depth of field. You can get great results but I'm not exactly rushing to buy one as it seems hard to get a straight answer about picture quality rather than the "it isn't £800 so it must be junk" reviewers.
They do have limitations, the f8 ones will be very dark and tricky to focus while the f5.6 ones are likely to have very shallow depth of field. You can get great results but I'm not exactly rushing to buy one as it seems hard to get a straight answer about picture quality rather than the "it isn't £800 so it must be junk" reviewers.
Matt
Shooting the Welsh Wilderness with K-m, KX, MX, ME Super and assorted lenses.
Shooting the Welsh Wilderness with K-m, KX, MX, ME Super and assorted lenses.
Posted 13/02/2011 - 00:08
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ok thanks guys, the one I have seen says samyang (??) 500mm f6.3 mirror lens £109.99 3 year warranty. that's about all I know about it. (camera centre cardiff).
jacqui
Posted 13/02/2011 - 00:24
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Wonder if the Bubble Telescope comes in K mount ? And if there's a macro version
[i]Bodies: 1x K-5IIs, 2x K-5, Sony TX-5, Nokia 808
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283
Lenses: Pentax DA 10-17mm ED(IF) Fish Eye, Pentax DA 14mm f/2.8, Sigma 17-70mm f/2.8, Pentax-A 28mm f/2.8, Sigma 30mm F1.4 EX DC, Pentax-A 50mm f/1.2, Pentax-A 50mm f/1.4, Pentax-FA 50mm f/1.4, Pentax-A 50mm f/1.7, Pentax DA* 50-135mm f/2.8, Sigma 135-400mm APO DG, and more ..
Flash: AF-540FGZ, Vivitar 283
Posted 13/02/2011 - 09:40
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Smeggypants wrote:
Wonder if the Bubble Telescope comes in K mount ? And if there's a macro version
Smeggy, I'm guessing your fingers missed - Did you mean Hubble?Wonder if the Bubble Telescope comes in K mount ? And if there's a macro version
In which case you could get an adapter, but getting to the lens proves expensive .
Macro is definitely out!
Mike
.
Pentax:K5ii, K7, K100D, DA18-55, DA10-17, DA55-300, DA50-200, F100-300, F50, DA35 AL, 4* M50, 2* M135, Helicoid extension, Tak 300 f4 (& 6 film bodies)
3rd Party: Bigmos (Sigma 150-500mm OS HSM),2* 28mm, 100mm macro, 28-200 zoom, 35-80 zoom, 80-200 zoom, 80-210 zoom, 300mm M42, 600 mirror, 1000-4000 scope, 50mm M42, enlarger lenses, Sony & micro 4/3 cameras with various PK mounts, Zenit E...
Far to many tele-converters, adapters, project parts & extension tubes etc.
.[size=11:].Flickr• WPF• Panoramio
.
Pentax:K5ii, K7, K100D, DA18-55, DA10-17, DA55-300, DA50-200, F100-300, F50, DA35 AL, 4* M50, 2* M135, Helicoid extension, Tak 300 f4 (& 6 film bodies)
3rd Party: Bigmos (Sigma 150-500mm OS HSM),2* 28mm, 100mm macro, 28-200 zoom, 35-80 zoom, 80-200 zoom, 80-210 zoom, 300mm M42, 600 mirror, 1000-4000 scope, 50mm M42, enlarger lenses, Sony & micro 4/3 cameras with various PK mounts, Zenit E...
Far to many tele-converters, adapters, project parts & extension tubes etc.
.[size=11:].Flickr• WPF• Panoramio
Posted 13/02/2011 - 10:07
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Samyang have good build quality and make some excellent lenses, I haven't tried their mirror lens though so can't comment. My advice would be to go to the shop with your camera and ask if you can test it with a view to buying. A quick shot of the brickwork on the shop over the road from the door should give you some pointers, although you really need a tripod to get the best from long lenses.
Matt
Shooting the Welsh Wilderness with K-m, KX, MX, ME Super and assorted lenses.
Shooting the Welsh Wilderness with K-m, KX, MX, ME Super and assorted lenses.
Posted 13/02/2011 - 10:21
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Got two of the things. One in K-mount (an original T-mount, ie not T2) and one in M42. Cannot remember when I last used either of them.
A 300mm hung on a K200 has reached as far as I have wanted to.
Geoff
A 300mm hung on a K200 has reached as far as I have wanted to.
Geoff
Water can wear away a stone - but it can't cook lunch
X-5
istDS
K2000
P50.
Lenses Digital: 50-200, 18-55 KAF: 28-80.
Lenses KA & K: SMC-KA f2.0, SMC-K f1.4, SMC-K f1.7 Tokina KA 28-70 , SMC Pentax 70-210 F4, Sigma KA 75-300 , Hanimex 500mm Mirror, and the Tamron Adaptall-2 stuff.
and then there's all the M42 kit, and the accessories ...
X-5
istDS
K2000
P50.
Lenses Digital: 50-200, 18-55 KAF: 28-80.
Lenses KA & K: SMC-KA f2.0, SMC-K f1.4, SMC-K f1.7 Tokina KA 28-70 , SMC Pentax 70-210 F4, Sigma KA 75-300 , Hanimex 500mm Mirror, and the Tamron Adaptall-2 stuff.
and then there's all the M42 kit, and the accessories ...
Posted 13/02/2011 - 11:40
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You've had lots of answers I see, but I'll just throw in my 2c. I've owned the Tamron Adaptall-2 500mm f8 mirror and MTO 1000mm f11 mirror.
500mm f8 mirror lenses have a shorter DoF than a 300mm f5.6 lens, not the other way around. The longer focal length more than makes up for the smaller aperture.
Samyang and associated brands (Rokinon, Opteka, etc) mirror lenses have a decent, but not brilliant, reputation. The Tamron on the other hand has a great reputation. If you're thinking about spending £110ish I would be looking for the Tamron instead. (It should possible to get one for around £125 or so, but you'll have to look for a while. Avoid the rip off Buy-It-Now outfits on ebay who want £200 for this lens).
500mm f8 mirror lenses have a shorter DoF than a 300mm f5.6 lens, not the other way around. The longer focal length more than makes up for the smaller aperture.
Samyang and associated brands (Rokinon, Opteka, etc) mirror lenses have a decent, but not brilliant, reputation. The Tamron on the other hand has a great reputation. If you're thinking about spending £110ish I would be looking for the Tamron instead. (It should possible to get one for around £125 or so, but you'll have to look for a while. Avoid the rip off Buy-It-Now outfits on ebay who want £200 for this lens).
Tim
AF - Pentax K5, Sigma 10-20/4-5.6, Tamron 17-50/2.8, Sigma 30/1.4, Sigma 70-200/2.8, Tamron 70-300/4-5.6
MF - Vivitar CF 28/2.8, Tamron AD2 90/2.5, MTO 1000/11
Stuff - Metz 58 AF1, Cactus v4, Nikon SB24, Raynox 150, Sigma 1.4x TC, Sigma 2x TC, Kenko 2x macro TC, Redsnapper 283 tripod, iMac 27”, Macbook Pro 17”, iPad, iPhone 3G
Flickr • Fluidr • PPG • Street • Portfolio site
Feel free to edit any of my posted photos! If I post a photo for critique, I want brutal honesty. If you don't like it, please say so and tell me why!
AF - Pentax K5, Sigma 10-20/4-5.6, Tamron 17-50/2.8, Sigma 30/1.4, Sigma 70-200/2.8, Tamron 70-300/4-5.6
MF - Vivitar CF 28/2.8, Tamron AD2 90/2.5, MTO 1000/11
Stuff - Metz 58 AF1, Cactus v4, Nikon SB24, Raynox 150, Sigma 1.4x TC, Sigma 2x TC, Kenko 2x macro TC, Redsnapper 283 tripod, iMac 27”, Macbook Pro 17”, iPad, iPhone 3G
Flickr • Fluidr • PPG • Street • Portfolio site
Feel free to edit any of my posted photos! If I post a photo for critique, I want brutal honesty. If you don't like it, please say so and tell me why!
Posted 13/02/2011 - 12:19
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Eider Drake Tamron SP500mm
Swan Tamron SP500mm
Hi Jacqui. The Tamron is an excellent lens, that can produce excellent photos. I can't speak for other lenses. There are limitations with it though. Out of focus highlights can produce a "doughnut" effect also if the subject is close, as opposed to isolated from an out of focus background, the bokeh can be messy.
There is a group on flickr for mirror lenses mirror reflex
Swan Tamron SP500mm
Hi Jacqui. The Tamron is an excellent lens, that can produce excellent photos. I can't speak for other lenses. There are limitations with it though. Out of focus highlights can produce a "doughnut" effect also if the subject is close, as opposed to isolated from an out of focus background, the bokeh can be messy.
There is a group on flickr for mirror lenses mirror reflex
Posted 13/02/2011 - 12:48
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ok thanks everyone, Im not sure if this would be right for me.I am just wanting more zoom, I have just seen a sigma AF 28-300mm lens for £100. any thoughts? I know that's a big zoom but thought for a walkabout lens it would be great (not too fond of changing lenses too much) does anyone know if this lens is any good? thanks.
jacqui
Posted 13/02/2011 - 13:48
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Or if anyone can recommend a half decent zoom (more zoom than the 50-200mm) keeping in mind funds are pretty limited (as usual) thanks.
jacqui
Posted 13/02/2011 - 14:06
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You could buy the Pentax 55-300 DAL it is awesome DAL is the cheaper version as it has a plastic mount and no quick shift and also doesn't come with a hood you can pick a brand new one up for circa £130.
It is a stunning lens and there are hundreds of example photos all over the gallery. You won't regret it.
It is a stunning lens and there are hundreds of example photos all over the gallery. You won't regret it.
Flickr
"Life is what happens to you while you're busy making other plans" (John Lennon)
"Life is what happens to you while you're busy making other plans" (John Lennon)
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