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Lomo 80mm Test report

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#1 Tokoloshe81

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Posted 13 November 2012 - 05:55 AM

any chance someone can help me get my head around this test report its all way over my head

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#2 dougm

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Posted 13 November 2012 - 10:44 AM

The two figures near the bottom are what concern you, under "optical quality". The last figure, P-V, indicates the total wavefront to be at least
1/6th wave, while the RMS figure above that (an average of the smoothness of the entire surface) is 1/33rd wave. The first figure tells you the gap between the highest peak and lowest valley ( the P-V figure), woe the RMS figure gives an average for the whole surface.
Both are excellent! That's my rough understanding of what you have.

#3 Sasa

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Posted 13 November 2012 - 10:46 AM

It just says that your lens is well within its specifications. For example RMS=0.021*lambda translates to
Strehl of 0.983, pretty good. Enjoy it! BTW, we seem to have same astroimaging setup (I have as well this lens and Atik314).

#4 Tokoloshe81

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Posted 13 November 2012 - 11:44 AM

thanks for the replies glad someone can make sense of it all

we seem to have same astroimaging setup (I have as well this lens and Atik314).


i do love the scope but i've really only used the kit in anger a few times as the weather has really been against me

#5 jtaylor996

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Posted 13 November 2012 - 12:28 PM

I've noticed with LOMO tests, the first attempt that passes gets the signature. They don't try to knock it out of the part on these, so you're seeing something a little different that the results that Rohr gets. The minimum spec is .975 Strehl, so you know your scope is at least .983, but it could be higher than that, even.

Mine looked to be tilted in the i-gram, but still passed .975, so they didn't go back and correct the setup to see what it was actually capable of. I kinda wish they did... but it really makes almost no difference at this level.

#6 Sasa

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Posted 13 November 2012 - 12:30 PM

Do you have a field flattener? Although the chip is relatively small, one could see the effects of the curved field on it already. To tease you, you can have a look on my web page, most of the images there are through this scope and camera.

#7 Tokoloshe81

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Posted 13 November 2012 - 01:04 PM

i do have a reducer/flatener for it yes. i've popped up some of my images here

http://www.cloudynig...ber=5517901&...

#8 Sasa

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Posted 13 November 2012 - 05:06 PM

These are very good, indeed. Especially the color versions look dramatic.






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