anyone modded eos r successfully for astrophotography?

bc0428 wrote:

Definitely a hell of an excellent work Marco! I am more sure now it won’t go wrong with the R. I mainly do astrophotography with filters, bortle 8 skies here in Hong Kong, dont have the “drive to dark skies” option. And I believe I should be modding my R right away, i know how it differs from an unmodded one with my previous modding experience on 500d. However, i dont think the 30x is really that useful to me, the 10x regular zoom on R is quite useful enough which I am using it to focus very often.

Now I just have to be patient before I find the instructions or diagrams how to mod the R, i hope I won’t break the beast!

I'm not sure how to go about modding a sensor.  That would be a little too technical for me but if you've done this before then you've probably got a better idea how to go about that.
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Those images were very simple test shots taken with a regular tripod. I wanted to see what each camera and lens was capable of.  I'd probably show more care if reshooting today.  One really impressive difference was in how certain RF lenses perform compared to the older EF lenses.  A lot of Astrophotographers using the R cameras have had great success with the new RF 50mm f/1.2L and the RF 85mm f/1.2L lenses.  The new RF 85mmL lens has improvements and technology in the optical elements that vastly exceed the older EF versions.  Coma is now beautifully controlled, as is Chromatic Aberration (due to the Blue Refractive Optical element).  For regular Terrestrial photography, this is not quite as noticeable - but with Astrophotography, the differences have an enormous effect in image quality and image integrity (especially in relation to color accuracy).
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A great example (directly below) shows how much Chromatic Aberration and Color Blooming occurs with the older EF lenses compared to the newer RF lenses.  All that purple fringing (CA) on the left is missing from the shot taken with the RF lens on the right.  The "Southern Pleiades" on the lower left of the images should be blue... but the Purple Fringing from the EF lens has turned it a crimson-purple color.  The sharpness of the stars are very poor in the EF shot.  But they are perfect pinpricks of light in the RF images instead of smudges with color-bleed like the ones from the EF lenses.
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The Southern Pleiades are on the lower left.

Not bad.  Imagine using smaller apertures and tracking this shot for more than 6 seconds?

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Obviously, those differences only relate to lenses.  If you are using telescopes with your camera, the quality of the optics in your telescope with be part of the equation.   Some people will prefer to shoot deep space objects with longer focal lengths but one of the reasons I prefer using the EOS Ra (or any mirrorless camera) is because I can capture astro-landscapes with it.  I can't do that with a plug-in CCD camera designed to connect to the rear of a telescope (or the front of one if using an Astrograph model).
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Many Astrophotographers prefer to use APS-C cameras due to the advantages of the (approx) 1.6x crop. Of course, a Full Frame sensor has its own benefits.  Getting a camera sensor modified these days is rather easy so there should be a lot of alternatives out there for you to consider.  The EOS R cameras have come down in price recently due to newer releases.  You ought to be able to find someone that can Mod your sensor.  I'd have considered it myself if the folks doing the modding hadn't shut down during the Pandemic.  But that 30x magnification on the LCD during Live View on the EOS Ra is a welcome tool that makes Manual Focus a breeze.  I can usually nail the focus in 4 seconds or less using this feature.
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Early Astro-landscape test with the EOS Ra.