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Does size matter?

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#1 RightWill

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Posted 19 August 2014 - 07:43 PM

Concerning video cameras, does the size of the CCD chip make a difference. Looking at the Mallincam Jr Pro which has a 1/2" chip and the AVS APU-1 which has a 1/3 " chip, is there a noticeable difference in the image produced? I've heard color sensors are lower resolution than the B&W, but what about both of these cameras in color?

 

 



#2 ccs_hello

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Posted 19 August 2014 - 10:03 PM

Rick,
 
Your question is a complex topic and cannot be easily generalized.
 
This CN thread could be a starting point.
 
Clear Skies!

 

ccs_hello


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#3 Dwight J

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Posted 20 August 2014 - 03:38 AM

The most noticeable thing is the larger field of view with the 1/2" chip.  There are likely differences in many characteristics due to different chips being used.  The JrPro can be ordered with an EXview HAD chip as well.  User variables such as location, temp, filters, focal ratio, type and aperture of telescope, software used, different monitors, cables, etc. make unbiased comparisons all but impossible unless someone has both cameras and even then there are many variables to control.  Generally a larger chip with more field would be preferred so less aggressive focal reduction would need to be used or similar reduction results in a larger field. This makes framing easier, goto's easier, and tracking less critical.  These are not trivial when using these small chipped cameras.


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#4 Dom543

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Posted 20 August 2014 - 12:57 PM

Focal reduction is also one of the components in the equation. Some say that smaller sensors allow for stronger focal reduction without negative side effects. I.e. the light gathered by the objective can be concentrated on a smaller sensor area. Smaller sensor with stronger focal reduction can yield the same FOV as a larger sensor with milder reduction. But the image on the smaller sensor will be brighter. The anticipated AVS x0.18 reducer will be a good testing ground for this line of thought.

 

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#5 Dwight J

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Posted 20 August 2014 - 02:36 PM

Focal reduction is also one of the components in the equation. Some say that smaller sensors allow for stronger focal reduction without negative side effects. I.e. the light gathered by the objective can be concentrated on a smaller sensor area. Smaller sensor with stronger focal reduction can yield the same FOV as a larger sensor with milder reduction. But the image on the smaller sensor will be brighter. The anticipated AVS x0.18 reducer will be a good testing ground for this line of thought.

 

--Dom

Stronger reduction with a smaller sensor is possible as most aberrations will fall outside the field of the chip, theoretically.  One aberration that will be highly problematic is vignetting.  A 0.18X reducer will likely have plenty of that.  I have had to back off from F2.5 to F4 due to increased LP caused by LED street lights being installed.  The vignetting at the faster ratio was overwhelming.  Another case of more is better until it is too much.








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