REIKAN FOCAL PRO VS LENSALIGN SERIES

Generally at around the point where the quality at a particular aperture (as you close the aperture down) drops below the quality at wide-open is the point where the effects of diffraction are beginning to be reduce the sharpness, and in the above chart this would be around f/8 or f/9. Thirdly, as you close the aperture on a lens itвЂ™s performance will get better, but with a very small aperture the effects of diffraction will start to mean there is a loss in sharpness at the sensor. Secondly, the wide-open value (at f/2.8) is still very good, meaning this lens will perform very well wide open. We can also determine that everything between about f/3.2 and f/7.1 will have excellent sharpness and in reality will beВ indistinguishableВ from the best sharpness value in real shooting. So what does this tell us? Well, first, we can determine that the peak of the graph is around f/4 to f/4.5, meaning these are the sharpest apertures of the lens. The chart below is copied from the report produced by FoCal after the Aperture Sharpness test was run on a Canon EOS-1D Mark IV with the Canon EF 100mm f/2.8L Macro IS USM lens:Д¬anon EOS-1D Mark IV and Canon EF 100mm f/2.8L Macro IS USM Aperture Sharpness

REIKAN FOCAL PRO VS LENSALIGN SERIES

The Aperture Sharpness TestДЇoCalвЂ™s Aperture Sharpness TestВ is designed to show you the sharpest aperture of your lens by taking a series of shot from the narrowest aperture (largest f-number) through to the widest aperture (smallest f-number) and plotting the results.ДЄlthough the result is just a plot of the quality of the image against the aperture, there is a lot of information in these charts. Today, I want to show a comparison in the Aperture Sharpness test results from the EF 24-70 f/2.8L USM and the EF 24-70 f/2.8L II USM lenses, and also a comparison in the Focus Consistency between these two lenses. WeвЂ™re not quite at that point yet, but on working with the data we are finding a few interesting bits of information which is worth sharing. The plan has been to use this data to both improve the analysis and guidance in FoCal, and also to be able to compare your data to вЂњtypicalвЂќ copies of your body and lenses.

' I love Focal as I can sit on the couch and adjust my lenses properly.For quite a few months now, FoCal has had a Data Upload feature which has meant that people who use FoCal can optionally upload their data back to us at Reikan so we can analyse the results. Ie my 200-500 is adjusted for the 500mm end and my 70-200Fl is the median as the difference between the two ends if 3 units. What I do is either test both ends and pick the median between the two adjustments if they are close or if they are far apart I adjust it for the focal length is use most. But then you are paying 10-20K for the zoom. the expensive cinema zooms have an adjustment to fix the lenses to be parfocal.

The zoom lenses are problematic as still camera lenses are not parfocal. I don't worry because I can fine tune the focus and it is not out of range on any of my bodies. I have one lens that is very largely minus. All Melville will do is put some shims in (or take them out). If you get a lens that needs lots of minus and try to use it on a body with lots of minus then there could be a problem. If you can get a sharp focus who cares what the number is.

Reikan focal pro vs lensalign