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Old 08-09-2007, 10:20 AM
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[1ponders] (Paul)
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Old 08-09-2007, 02:10 PM
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Originally Posted by Dennis View Post
Hi Paul

Here are a couple of 800 x 600 crops from the 3008 x 2008 jpg original. The 1st image is as is; the 2nd one has been smart sharpened in CS3.

The 3rd file is the original full frame 3008x2008 resampled down to 1024x681. No processing applied.

Subject to lens distance around 10 metres.


Now that's some sexy bokeh!

My guess is that it'll be CA to hell.
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Old 10-09-2007, 09:09 AM
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Just one small remark from me re mirror (maksutov) lenses..
Anyone who have a guts to do some modification could extend the focus far beyond the original limits, both for FL and position of the focal plane.
I have done this on my MTO1100 (it was an excellent decision to get one ~25 year ago, perfect optics) and then recently on two Rubinar's: 1000mm and 500mm (for my friend, he needed this done for a very special project).
The trick is to remove the stops such that the focus ring can rotate a bit further in both directions.
What you get with this mod is the optical system that can have up to 1/2 of the original FL and the focal plane very close to the lens body, and 2~3x the focal length (and no need for Barlow) and extended focal plane to up to 30cm out.
If you want to know more about it, I can supply you with precise How-to instructions and some photos (for Rubinar 1000, I do not have photos of Rubinar 500 mod but it is very easy to do, much easier that Rubinar 1000 mod)
BTW, The 500 mm lens discussed here by Paul is most likely Rubinar 500 (Russian).
Have a look at www.rugift.com.

Last edited by bojan; 10-09-2007 at 09:33 AM.
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