Sunday 22 January 2023

Canon EOS R5 full frame compared with x1.6 crop function - January 2023

Almost once a week a visit to the town centre at Holmestrand, Vestfold is made, not specifically to birdwatch but there is always an hour or so to kill, so it is used to count and register its wintering ducks and gulls in the small-boat harbour. There is rarely any variation in the species present but it often has good numbers of Common Goldeneye which may be observed at very close range due to their familiarity with the many people that use the waterfront walkway. Occasionally there are also good numbers of Mallard, Common Eider and the resident Herring Gulls. On occasions one or two Great Cormorants may sit on the jetty posts or hunt fish in the harbour, so all in all not the most exciting collection of species. On 19th January, the weather was a cold ca. -3 degrees centigrade, light breeze, and overcast with ca. 30cm snow/ice underfoot when it was decided to compare the difference between using the normal full frame modus with the built in x1.6 crop function on a Canon EOS R5 camera and RF 100-500mm lens. Using the x1.6 crop function with the lens at 500mm will give an equivalent of 800mm magnification and may be preferable to using an expensive x1.4 converter, which will reduce the smallest aperture by at least on f-stop and possibly negatively effect the focusing speed of the lens. A resting second year Great Cormorant was used as a suitable model although didn't really stay as long as I had hoped so therefore this test will be repeated later. Provisionally, the results shown here indicate that there is very little quality difference between the finished  JPEG cropped images that have been processed from the original CRAW-files using Adobe Lightroom and Topaz De Noise AI programs. The amount of heavy cropping applied to the full frame images are comparable to that applied to the x1.6 images, making the finished magnification about the same physical size for all finished images. The original CRAW file size for the full frame images were ca. 30 MB and for the x1.6 images ca. 11.5 MB. An image taken using the x1.6 function and full RAW would have a ca. 24 MB size, although this was not tried on this occasion. The resulting file sizes after processing of the full frame and the x1.6 images where roughly the same ca. 3.0-3.5 MB. Unfortunately there was a slight difference in ISO setting between the full frame and x1.6 originals, but this does not seem to have affected the results drastically.         

Great Cormorant (storskarv) Phalacrocorax carbo second year - Holmestrand 19th January 2023.
Cropped JPEG image from full frame (500mm), CRAW f/7.1, 1/640, 2000 ISO, original. 

Great Cormorant (storskarv) Phalacrocorax carbo second year - Holmestrand 19th January 2023.
Cropped JPEG image from x1.6 crop (800mm), CRAW f/7.1, 1/320, 1000 ISO, original. 

Great Cormorant (storskarv) Phalacrocorax carbo second year - Holmestrand 19th January 2023.
Cropped JPEG image from x1.6 crop (800mm), CRAW f/7.1, 1/320, 1000 ISO, original. 

Common Goldeneye (kvinand) Bucephala clangula second year - Holmestrand 3rd January 2023.


Common Goldeneye (kvinand) Bucephala clangula second year - Holmestrand 3rd January 2023.

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