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View Full Version : Legacy Lenses Opteka 500mm mirror



ghenton
09-26-2008, 09:19 PM
Opteka
Model - MF 500mm f:8 Mirror Lens
Groups/Elements: 8/9 <-----mine was 4/5 - 2 mirrors and 3 glass
Diameter: 3"
Length: 3.4"
Weight: 360 grams
Filter Size Front: 72mm
Aperture: f:8
Macro Magnification: 1:2.7
Minimum Focus Distance: 5.5'
Manual Focus: Yes
High quality crystal optics
Fully Multi-coated
Made in Japan <----- Mine was made in Korea
T mount - 4/3s


PRO
Cheap
500mm(1000mm effective)
Cheap
very light weight
Cheap
very little Chromatic Aboration
Cheap
fun
Cheap
Very Compact


CON
image stabilized or tri-pod a must
fixed Aperture
poor contrast
soft colors
difficult to focus
shallow DOF
poor/strange bokeh
narrow field of view


The inexpensive mirror lenses are not for everybody and requires a bit of experience with them to get the results you might hope for. To get results, you must run pictures thru software. The results I have gotten have ranged outright c**p to good. I bought this lens just as an experiment to see for myself if the were as bad as rumored. What I found is that you need a bright sunny day so you can get enough light to over come the f8 aperture and the long lens camera shake. It is very difficult to focus, not only because it is manual, but even with about 270 degrees of rotation on the focal ring, the focus was extremely sensitive. Less than 1 degree of rotation was more than enough to make or break focus. The DOF was very shallow at 10meters DOF is about 6cm. There is little CA as there is not much glass in this lens. A large lens on the front and 2 smaller ones in the rear. A little bit of vignetting is visible There is a large mirror at the rear and a small one at the front. The Bokeh can be distracting and was best if the background was open sky or something without detail. Also I found that although this lens will focus to macro I only got poor images, soft & fuzzy. That said with good light and image stabilized camera I did get some decent $100 lens images. I needed to post process by pushing up the contrast and just a little sharpening. I will take it down to the local duck pond or the bird bath out back and play, I don't think National Geographic will use any of the images but the pictures are decent and I had fun and the lens is cheap cheap.



Gerry

ghenton
09-27-2008, 05:48 PM
Here are 2 images taken at ~3 meters f8, with the Opteka 500mm mirror and a Sigma 50-500mm@500mm. there does seem to be a bit of difference in field of view but it was taken tri-pod mounted. First image is Opteka, second the Sigma. These are out of camera neutral settings and only resized for web. This is about as close as the Sigma 50-500mm can focus so used this as a start point.

ghenton
09-27-2008, 05:51 PM
These are at ~10meters same settings. At this distance and greater The Opteka seemed to work better.

ghenton
09-27-2008, 05:55 PM
This is the Opteka at macro focus ~2 meters, focus is on the nose

ghenton
09-28-2008, 10:08 AM
These are the same images after just a quick bit of post processing, (increase contrast and a light bit of sharpening) they are not that bad.

Steve Adams
09-28-2008, 04:57 PM
Wow,

im impressed for the cost. Its good to know someone can get 500mm for cheap and thats reasonable...I plan on getting some of these cheap lenses to play with. for general shooting they should be fine.

cifcap
09-29-2008, 02:29 PM
These are the same images after just a quick bit of post processing, (increase contrast and a light bit of sharpening) they are not that bad.
Very informative assessment of this lens and thanks for sharing samples and thoughts.

:thumbup:
JW

Declan79
11-28-2010, 02:53 AM
Now i know about this mirror lens worked, thanks mate

Garrudae
09-21-2011, 12:33 PM
first off, those are optically not very good. Second, youd be using a step-down ring to get a 37mm filter on a 55mm lens, meaning youll have huge vignetting with a little round picture in the center.

RAH
09-23-2011, 08:28 AM
Second, youd be using a step-down ring to get a 37mm filter on a 55mm lens, meaning youll have huge vignetting with a little round picture in the center.
Huh? I don't understand what you are referring to in this thread. Who said anything about a filter?

MikeL
09-23-2011, 03:05 PM
Thanks for the review and samples. Not very impressive resolution or contrast. I think I'll save my $100 and put it toward something better.

bravo
03-22-2012, 10:48 AM
Hello,
Well do you think 500mm is quite good mirror for camera?

ghenton
03-22-2012, 12:16 PM
Hi;
The Mirror lenses are a best value 500mm lens costing from under $100 and up. They have a wide focal range from 3' to infinity. There is little to no chromatic aberration. It is compact and light weight. That said they are difficult to use.
The 1000mm effective focal length and fixed f8 aperture would be a challenge under the best circumstances using any technology. It is a fixed focal length lens, you need to use your "2 feet" zoom. Image stabilization is a must. The focus is manual and difficult to nail. Mirror lenses by its nature have low contrast, this can be adjusted post camera in software. Bokeh can be distracting (light donuts).

My conclusions have not changed from the original postings, It is a cheap fun lens to use when I went down to the bird park / duck pond. I have 4 mirror lenses of different makes, all are about the same ( opteka, pentax, zeis and a russian lens) image quality but better build. I take one about once a month out to play with just for giggles. I have about 350 legecy lenses in my collection.

Gerry