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8in f2.65 ross test set up help

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33 replies to this topic

#26 Pinbout

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Posted 10 October 2019 - 08:31 PM

No get 3 lines on both sides of RoC.

 

what your describing is the grating acting like a ke



#27 macleod

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Posted 10 October 2019 - 09:20 PM

Danny one side is perfectly straight -in my eyes could not be better. The inside roc i,m not sure of , because by adjusting lens and source I can get that almost as straight. I don,t think I,m far off for this fast mirror.Stew.



#28 macleod

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Posted 10 October 2019 - 09:24 PM

Oh! forgot to ask - in Ross how or what determines in or out of ROC ? What should the turning point look like ? Stew.



#29 Pinbout

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Posted 10 October 2019 - 10:13 PM

You shouldn’t adjust the lens once the distance is measured.

 

operating the grating behind the lens is just like at RoC, don’t complicate it. 

 

its just forward alittle cause of the lens.

 

 

so you only move the grating/led once the lens is set - the only difference from the real RoC is that your testing a 0 conic instead of a -1 conic.



#30 Pinbout

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Posted 10 October 2019 - 10:18 PM

This one goes thru the “modified” RoC

 

https://www.youtube....hyN0oJICs2L6aP7



#31 MKV

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Posted 11 October 2019 - 12:32 AM

 9) Now move only the Ronchiscreen/light source  forward or back just like your doing a standard Ronchi test so you reduce the number of lines to 3 or 4. Now you can go from inside of focus to outside and examine the shape the Ronchi lines.  

Hi Dave,

 

Can you show in OSLO raytracing how this works? Note thickness 0 and 5 have to be the same but opposite in sign.

 

Thanks,

Mladen

 

 

mcleod_rnl_1.jpg



#32 macleod

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Posted 11 October 2019 - 01:19 AM

Thanks Danny, that video is what I,ve been going thru. Think I might call it quits, after using it at anything under125x in scope looks good. Macleod.



#33 Pinbout

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Posted 11 October 2019 - 05:06 AM

Well it is a widefield and it is you mirror. 

We just want the best for you grin.gif


Edited by Pinbout, 11 October 2019 - 05:08 AM.

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#34 DAVIDG

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Posted 11 October 2019 - 08:34 AM

 Macload,

   As I described in my instruction and what Danny states, once you  set the lens to mirror spacing you don't change it. You just move the grating/light source just like your doing standard Ronchi test. Every is the same as a standard Ronchi test, testing for a spherical  mirror. It is  that simple. 

 

           - Dave 


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