Commons:Quality images candidates/Archives September 15 2014

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Consensual review[edit]

File:Alhambra_evening_panorama_Mirador_San_Nicolas_large_pano_0EV_sRGB.jpg[edit]

Thanks for your review, DXR. Have you considered in your review that it is +60 Mpixel image? If you look at the same photo downsampled to 10 Mpixels it is crisp when viewed in 100%. I think it is unreasonable to pixelpeep at resolutions larger than the equivalent to 10 Mpixel in a QIC review, which is still much more than minimum resolution. Moving to CR to hear the opinion of other reviewers. --Slaunger 21:12, 7 September 2014 (UTC)[reply]
Sorry, Slaunger, don't get me wrong, but I do not think that the 10Mpix version is crisp (I also think that 1500 pix on the short side is a bit problematic for a panorama) and the single shots are clearly blurred. I get the pixelpeeping argument about corner softness etc., but a panorama of many unsharp images will struggle to be an QI in my opinion. It really is a bit of a technique error, but something that happens to everyone of us from time to time. Just avoid shooting at ISO 100 and 1/40, (ISO 400 and 1/160 would certainly have given you better results) especially if you can downsample in post. --DXR 08:23, 8 September 2014 (UTC)[reply]
Sorry, DXR, but I do not understand why ISO 400 and 1/160 s would have been a better choice? The photos were all taken with the camera mounted on a rugged tripod and are based on the middle of three raw exposures separated by 2 EV, and I had a 2 sec delay from pressing the shutter button. My mediocre sensor is pretty noisy at ISO 400. Why should going to a faster shutter time help? Downsampling is irreversible and will always lead to information loss. If you want to make a large scale print, it will always be better to use the full resolution version as compared to the a downsampled version albeit it may be soft on a pixel level. The downsampled version will suffer from pixelation when scaled up again to full scale. If I had nominated the 10 Mpixel version as a single shot with that quality it had surely been a QI. The technique used should not be determining for it to be QI-worthy or not. Just because you know it is a stitch of many individual single shots is irrelevant for the QI assessment of the image as such. It is a way for me to mitigate that I have entry level DSLR gear. This is QIC not FPC. --Slaunger 20:37, 8 September 2014 (UTC)[reply]
Slaunger, I find it hard to believe that your gear is to blame. A 600D is a good camera and certainly not the limiting factor and as you rightly say, DOF is neither. I do not believe that your lens will produce images that are so blurred either, since sites like photozone show decent sharpness figures in tests (and also your plane shots are nicely sharp!). To my eyes the images simply look blurred due to camera shake or some other movement of sorts. I know that my camera will sometimes produce blurry files even mounted on a good tripod since mirror slap is significant. Perhaps your camera was also exposed to wind or comparable factors, perhaps the IS malfunctioned. I am confident that your equipment is capable of producing much better results and it is probably more useful to enquire why that was not the case instead of arguing that any large image will get QI if downsampled or viewed at small sizes (which is of course true, unfortunately). When I consider a QI, I think I should also ask if some random user would be happy if they printed the file based on its resolution, which is pretty large here, and the result would probably be a no. Please do not take this as personal criticism, but wouldn't it be more helpful to try figure out the reasons for the flaws in quality of your panorama to improve upon it in the future? (Feel free to continue this disc on my talk page) --DXR (talk) 22:24, 8 September 2014 (UTC)[reply]

 I withdraw my nomination Thanks for the reviews. I have come to the conclusion the quality issue is due to mirror slap in combination with insiffient tightening of the grip for azimuth angle control on the tripod. -- Slaunger 11:41, 14 September 2014 (UTC)[reply]