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Not bad. Guy shoots Saturn and rings with 600mm f.l. lens

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#1 RichA

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Posted 05 June 2020 - 05:03 PM

On m4/3rd camera, 20mp equates to about 80mp on a FF camera pixel density.  He used a 300mm lens and 2x converter for 600mm.  The net magnification (as compared to the human eye) is about 18x.  (1200mm equivalent lens focal length).  Pretty good. 

 

https://www.dpreview...s/post/63998532

 


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#2 17.5Dob

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Posted 05 June 2020 - 07:38 PM

On m4/3rd camera, 20mp equates to about 80mp on a FF camera pixel density.  He used a 300mm lens and 2x converter for 600mm.  The net magnification (as compared to the human eye) is about 18x.  (1200mm equivalent lens focal length).  Pretty good. 

 

https://www.dpreview...s/post/63998532

Pfft...should have just used a 3,000mm "equivalent fl"  point and shoot Nikon P1000...

Again... crop factor......is a totally meaningless advertising term...and should have died out 15 yrs ago.....a 20.4 Mp M4/3 has the exact same size pixels as a full frame Sony A7IV.....600mm is still 600mm...

The standard unit of measurement in AP is "pixel scale". A  M4/3 camera ( or full frame camera) using 3.72um pixels and a 600mm lens has a pixel scale of 1.28"/pixel

The P&S Nikon P1000 has a pixel scale of 0.51"/pixel, at full zoom, 250% higher resolution than the M4/3 or FF......

And it wasn't a "600mm lens.." it was a 300mm lens and 2X barlow....An actual 600mm lens would have have twice the resolution .....due too it's larger aperture....

 


Edited by 17.5Dob, 05 June 2020 - 11:06 PM.

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#3 RichA

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Posted 05 June 2020 - 11:14 PM

Pfft...should have just used a 3,000mm "equivalent fl"  point and shoot Nikon P1000...

Again... crop factor......is a totally meaningless advertising term...and should have died out 15 yrs ago.....a 20.4 Mp M4/3 has the exact same size pixels as a full frame Sony A7IV.....600mm is still 600mm...

The standard unit of measurement in AP is "pixel scale". A  M4/3 camera ( or full frame camera) using 3.72um pixels and a 600mm lens has a pixel scale of 1.28"/pixel

The P&S Nikon P1000 has a pixel scale of 0.51"/pixel, at full zoom, 250% higher resolution than the M4/3 or FF......

 

P&S's were generally plagued by horrible noise and lens issues, like what you might have gotten from a DSLR 15 years ago.  But, Nikon did a good job on the P1000, with its insane zoom range.  I once mated a Pentax Q which was an interchangeable lens camera with a 1/2.3" 14MP sensor to a 7" Mak.  Huge image scale at prime focus, but was let-down by diffraction.  Lenses that are 600mm are 600mm, a lens doesn't magically change its native focal length when sensors are different sizes,  but the angle of coverage on a FF lens is 2x (roughly) that of m4/3rds (allowing some for the differences in geometry between the regular 3:2 ratio FF sensor and the 4:3 ration m4/3rds sensor) so while a m4/3 camera may only have 20mp, any specific area covered by a lens of the same focal length has the same resolution as an 80MP FF camera because the FF sensor is 4x the area of the m4/3rds sensor.  The new Sony A7IV is only 61MP.  However, Nikon and Canon supposedly have 80MP or greater FF sensor cameras coming and Canon announced a 150MP sensor some time ago, but haven't used it yet.


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#4 starblue

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Posted 06 June 2020 - 11:47 PM

On m4/3rd camera, 20mp equates to about 80mp on a FF camera pixel density.  He used a 300mm lens and 2x converter for 600mm.  The net magnification (as compared to the human eye) is about 18x.  (1200mm equivalent lens focal length).  Pretty good. 

 

https://www.dpreview...s/post/63998532

I saw that on dpreview and was quite impressed at how sharp it was. Recently I captured Venus' crescent phase with Panasonic's 100-300mm f/4-5.6 lens (v.1) @ 300mm (no tele-converter) and it didn't turn out nearly as sharp. It indicates just how great the optics are in Olympus' 300mm f/4 lens.




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