Thanks for posting. It would be very helpful, for me at least, if you could say a few words about the review as there are so many YouTube reviews that are not worth clicking on.
Chris Frost reviews are worth clicking though.Thanks for posting. It would be very helpful, for me at least, if you could say a few words about the review as there are so many YouTube reviews that are not worth clicking on.
Thanks for that, most helpful. I skimmed through until 8 minutes. The shots he did to check flare were poor ones - lights at night. The Nikon 500mm PF that uses DO optics, for example, has no problems with flare for such shots, the flare is seen under other conditions https://www.lenstip.com/540.9-Lens_...0_mm_f_5.6E_PF_ED_VR_Ghosting_and_flares.html He showed a shot of some lines on a chart. It would have helped if he had shown some shots of the same chart with a wider lens to see any differences.Chris Frost reviews are worth clicking though.
Image quality comes after the 8 minute mark in the video, if you want to skip right to it.
It's a positive review, focussing more on the handling of the lens with aspects like the weight distribution, IS, limited AF coverage etc, rather than the IQ, since the lens literally has only one setting. At which it is affected by diffration when testet on the R5, but still looking nice across the frame. I was surprised to see the lens handle flaring so well - As far as I know, this has been a weak point in past DO lenses?
The chart he uses is pretty large and is used for all his testing, so it is at least comparable across lenses. This lens looks much sharper in the center than his sample of the Sigma 150-600 C when both are compared wide open on ~45 MP FF cameras (R5, A7R III). Stopped down, his sample of the sigma became really sharp, so I guess with more pixel density they may be comparable.Thanks for that, most helpful. I skimmed through until 8 minutes. The shots he did to check flare were poor ones - lights at night. The Nikon 500mm PF that uses DO optics, for example, has no problems with flare for such shots, the flare is seen under other conditions https://www.lenstip.com/540.9-Lens_...0_mm_f_5.6E_PF_ED_VR_Ghosting_and_flares.html He showed a shot of some lines on a chart. It would have helped if he had shown some shots of the same chart with a wider lens to see any differences.
I guess that aiming an 800mm lens at the sun would be extremely prejudicial to the sensor...The chart he uses is pretty large and is used for all his testing, so it is at least comparable across lenses. This lens looks much sharper in the center than his sample of the Sigma 150-600 C when both are compared wide open on ~45 MP FF cameras (R5, A7R III). Stopped down, his sample of the sigma became really sharp, so I guess with more pixel density they may be comparable.
His reviews are not as technical and scientific, nor thorough as they could be. But they give a decent overview over many aspects of a lens that are not clear without looking at such a review. And he is way less obnoxious than many other folks on YouTube.
I also would have preferred to see his usual test for flaring using the sun. I guess you are right that it would have made for a much better point of comparison.
It's his English accent that makes him less obnoxious, just like Gordon Laing's! Actually, it's a serious point the British (European) reserve comes over and there is less hype, which I far prefer with my cultural background. I don't like that type of chart. I like to see ones with a selection of parallel lines, with groups getting progressively closer so you can see where the resolution gives up or gently converging lines as used in sites like the-digital-picture.The chart he uses is pretty large and is used for all his testing, so it is at least comparable across lenses. This lens looks much sharper in the center than his sample of the Sigma 150-600 C when both are compared wide open on ~45 MP FF cameras (R5, A7R III). Stopped down, his sample of the sigma became really sharp, so I guess with more pixel density they may be comparable.
His reviews are not as technical and scientific, nor thorough as they could be. But they give a decent overview over many aspects of a lens that are not clear without looking at such a review. And he is way less obnoxious than many other folks on YouTube.
I also would have preferred to see his usual test for flaring using the sun. I guess you are right that it would have made for a much better point of comparison.
They don't test for flare by pointing the lens directly at the sun, they have it peeking in at a corner or just outside it - see examples in the link I posted a few back. And that's when you see the effects of flare ruining contrast all over the image. It's a similar problem when photoing a backlit bird when the background light does the same thing and ruins contrast. A different type of flare is when you have small bright lights within a scene and you get halos around them. CF has just checked the latter type of flair but these 800mm lenses are used mainly for bird and nature photography where it's the overall contrast loss by flare from the sun or bright backgrounds that is the problem.I guess that aiming an 800mm lens at the sun would be extremely prejudicial to the sensor...
Anyway, apart from his chart-shooting, which doesn't do every lens justice (some very good ones suffer from a bit of field curvature), I really enjoy his "down to earth" testing.
He convinced me, to at least, take a close look at the RF 800mm...possibly even to buy one.
Almost as frustrating as interstellar travel being limited to the speed of light.