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Old 12-02-2016, 08:00 AM
aarong (Aaron)
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Field curvature of Meade ACF's

Hi all,

I'm trying to work out why I may have excessive field curvature (60-100% as measured by ccd inspector) in my photos from my 8" lx90 ACF f/10 and QSI 683WGS combination, but firstly, what have others measured from their set-ups using a Meade ACF f/10? I'm not sure what I should be expecting.

I noticed it why collecting subs for this image. The image has been cropped a little, but you can still see it.

I have also posted the same question in the lx90 yahoo user group.

Thanks,
Aaron
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Old 12-02-2016, 08:47 AM
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Atmos (Colin)
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I have some old images that I have taken with my full frame (36x24) DSLR through my 10" F/10, I'll run some of those through CCDInspector tonight.
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Old 12-02-2016, 01:01 PM
aarong (Aaron)
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Awesome! Thanks for doing that.

Aaron
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Old 16-02-2016, 08:05 PM
aarong (Aaron)
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I should also mention that I use a 2" nosepiece with the QSI. I have attached an example of the upper end of the field curvature I have measured and a sub.

Any measurements from others with similar set-ups or with an lx90 would be interesting and help to work out what field curvature I should aim for.

Cheers,
Aaron
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Click for full-size image (2015-07-09_startest-20.0C_30sec_1x1_L_frame1-1.jpg)
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Click for full-size image (_2015_07_09_startest_20_0C_30sec_1x1_L_frame1_1_FWHM.jpg)
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Old 17-02-2016, 01:11 AM
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jenchris (Jennifer)
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Looking at the sub you posted is nothing like the subs I get with my acf8.
I can see coma in the edge stars and the ones in the middle are oval.
This tuc47 is one I took in 2011 when I was just starting.
It's a single frame, unguided.
My stars are pretty much round to the edge of you ignore the lack of finesse in other areas
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Old 18-02-2016, 12:59 PM
aarong (Aaron)
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Quote:
Originally Posted by jenchris View Post
Looking at the sub you posted is nothing like the subs I get with my acf8.
I can see coma in the edge stars and the ones in the middle are oval.
This tuc47 is one I took in 2011 when I was just starting.
It's a single frame, unguided.
My stars are pretty much round to the edge of you ignore the lack of finesse in other areas
Thanks for this. Interesting...
What camera did you use?
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