M.Chapman Posted June 23, 2017 Share Posted June 23, 2017 3 hours ago, In my view said: Thanks for your time. I think I know what the issue is.. with the same lighting conditions and same workflow, I took another snap today but this time switched to my 50mm F1.8 and the results have surprised me! (please check the link below) Clearly Sigma 17-55 is not suitable for low light conditions or at least not as good as 50mm f1.8. I will try going to the same places this weekend and shoot with 50mm prime. Hope the results will be better this time. https://flic.kr/p/ULBE3s The issues I raised about noisy edges and pixelation in the sky are not caused by the lens. They are down to the processing. I'm not sure what your workflow was when producing the panorama, but something went wrong. The latest image looks sharper and doesn't have the edge and pixelation problems, but it hasn't had the same post-processing as "Evening on the Thames". Link to comment Share on other sites More sharing options...
David_Buzzard Posted June 23, 2017 Share Posted June 23, 2017 You've got a ton of digital noise and processing. My guess is that you're editing JPG files and getting built up compression artifacts. You should always shoot in RAW, and make sure the long exposure noise reduction is turned on. You can also make panoramas (I think) and HDR images in Lightroom that keeps them in the RAW format, which I think works a lot better. You're also getting some flaring around the light sources. Sigma's make pretty good lenses, so maybe it might be a not so great quality filter, or even one that's got a lot of wear on it. Link to comment Share on other sites More sharing options...
KTC Posted June 23, 2017 Share Posted June 23, 2017 For the noise and compression artifacts etc., it could be Flickr, but if not, then that's definitely a workflow issue from what you say. 8 hours ago, In my view said: Maybe lens is the problem here Check out the below image taken with canon 50mm f1.8 lens. I still see the flare but the quality looks better. Perhaps sigma is not better under low lights. https://flic.kr/p/UPoBJM Two (all 3?) of your original were panorama, this one looks like a standard image? If so, can't really compare the two. As others have said already, start off with some easier images to get going. In terms of the pano, while your 1st objective is to get accepted of course, you are also competing against other images not just on Alamy, but at other sites as well. Compare Tower Bridge full size on your "Evening on thames" to this 9 years old image on Wikimedia Commons. Link to comment Share on other sites More sharing options...
Marianne Posted June 23, 2017 Share Posted June 23, 2017 Did you use a cable release or remote trigger? At longer exposures, you can get camera shake on a tripod without one of those options. Link to comment Share on other sites More sharing options...
ChrisC Posted June 23, 2017 Share Posted June 23, 2017 14 hours ago, In my view said: Under the night photography yes I thought they were my best. But I guess the issue was with the lens as I was able to get sharp images using 50mm prime under similar conditions. https://flic.kr/p/ULBE3s But yes for now I will focus on simple images with good lighting. Baby steps! Thanks for your advice. No problem, generally Alamy just want a clear photo, unless it's for effect, such as burred movement for speed, or overly processed for effect can also get through I believe. Just worthwhile being careful and probably post anything artistic elsewhere for sale Chris Link to comment Share on other sites More sharing options...
spacecadet Posted June 24, 2017 Share Posted June 24, 2017 On 23/06/2017 at 06:37, M.Chapman said: The issues I raised about noisy edges and pixelation in the sky are not caused by the lens. They are down to the processing. I'm not sure what your workflow was when producing the panorama, but something went wrong. The latest image looks sharper and doesn't have the edge and pixelation problems, but it hasn't had the same post-processing as "Evening on the Thames". +1. The Sigma is perfectly capable of yielding sharp images and it did here. The problem lies elsewhere. You need to nail down your LR workflow so that you know what you've done from image to image. It's not difficult to introduce errors- we've all done it, my last one was accidentally clicking the watermark button in Lightroom export and getting a fail for it. Link to comment Share on other sites More sharing options...
In my view Posted June 24, 2017 Author Share Posted June 24, 2017 On 2017-6-22 at 21:08, M.Chapman said: I agree with Maria. I downloaded the 100% jpg of the 2nd image (Evening on the Thames) from Flickr. Assuming Flickr hasn't messed with the image, the sharpness looks marginal to me. But I'd also be concerned about the pixelation in the sky and the extra noise around edges. It looks like it may have had significant adjustment to the sky contrast in 8 bit mode, and that it's had significant sharpening with masking applied, which has really messed up the edges. It would be useful to see one of the RAWs this panorama was produced from. Here's a 100% crop from what I'm seeing in PS. Mark I agree there is something wrong I don't know was it the lens or the processing. But here is another image it doesn't have that pixelation issue but what about sharpness? https://flic.kr/p/W2B2HN Link to comment Share on other sites More sharing options...
M.Chapman Posted June 24, 2017 Share Posted June 24, 2017 9 minutes ago, In my view said: I agree there is something wrong I don't know was it the lens or the processing. But here is another image it doesn't have that pixelation issue but what about sharpness? https://flic.kr/p/W2B2HN As we have said, there are problems with the processing in the original "Evening on the Thames" image that you posted. Once the processing has gone wrong it is difficult to say if the lens was OK in that image because the image is degraded to much. Looking at your new 100% crop https://flic.kr/p/W2B2HN (which is from a different image of the same subject) I would say at 100% size (in my opinion) the sharpness is still marginal. If it was downsized it might be OK. The good news is that the pixelation and noise around the edges do not seem to be present in your new crop, so the processing (or lack of it) is better. If you can post a raw image, you'll get much clearer advice on whether you have a lens, camera setting, or technique issue. Link to comment Share on other sites More sharing options...
In my view Posted June 24, 2017 Author Share Posted June 24, 2017 20 minutes ago, M.Chapman said: As we have said, there are problems with the processing in the original "Evening on the Thames" image that you posted. Once the processing has gone wrong it is difficult to say if the lens was OK in that image because the image is degraded to much. Looking at your new 100% crop https://flic.kr/p/W2B2HN (which is from a different image of the same subject) I would say at 100% size (in my opinion) the sharpness is still marginal. If it was downsized it might be OK. The good news is that the pixelation and noise around the edges do not seem to be present in your new crop, so the processing (or lack of it) is better. If you can post a raw image, you'll get much clearer advice on whether you have a lens, camera setting, or technique issue. Where/how can I post the RAW image? This does not support attachments.. Sorry I am new. Link to comment Share on other sites More sharing options...
M.Chapman Posted June 24, 2017 Share Posted June 24, 2017 1 hour ago, In my view said: Where/how can I post the RAW image? This does not support attachments.. Sorry I am new. Google "free image hosting site" or maybe try here https://postimage.io/. Not sure if they have a size restriction or if they will post a RAW image though. I wouldn't post any valuable image here though because once you disclose the URL anyone can copy it. Link to comment Share on other sites More sharing options...
spacecadet Posted June 24, 2017 Share Posted June 24, 2017 I'm not sure how useful a RAW would be because LR applies default sharpening. What we really need to see is a straight full-size export with the OP being really careful about the export settings. But as he's shown us a sharp version he may have those right. Link to comment Share on other sites More sharing options...
M.Chapman Posted June 24, 2017 Share Posted June 24, 2017 1 hour ago, spacecadet said: I'm not sure how useful a RAW would be because LR applies default sharpening. What we really need to see is a straight full-size export with the OP being really careful about the export settings. But as he's shown us a sharp version he may have those right. Yes, but having the RAW bypasses that uncertainty (over the export settings as well as any NR and sharpening applied by a LR import preset that they forgot was in place...). Just makes diagnosis quicker and more accurate IMO. Link to comment Share on other sites More sharing options...
spacecadet Posted June 24, 2017 Share Posted June 24, 2017 True but my RAWs look pretty soft before default sharpening. Link to comment Share on other sites More sharing options...
MDM Posted June 24, 2017 Share Posted June 24, 2017 Very confusing thread this. The image at https://flic.kr/p/W2B2HN (also second image of original post) was taken with a different lens (55-250 zoom according to the exif) from that stated in the original post and the image quality is very poor compared to the others taken with the 17-55. Maybe somebody else has noticed this but I'm not seeing the comment. I'd suggest the OP starts again, shoots a scene in daylight, then the same scene at night with the same aperture and ISO, same focal length, manual focus, stable tripod - in other words the only variable is the light (and the shutter speed of course). Then they may be able to narrow down the problem. Link to comment Share on other sites More sharing options...
In my view Posted June 24, 2017 Author Share Posted June 24, 2017 20 minutes ago, MDM said: Very confusing thread this. The image at https://flic.kr/p/W2B2HN (also second image of original post) was taken with a different lens (55-250 zoom according to the exif) from that stated in the original post and the image quality is very poor compared to the others taken with the 17-55. Maybe somebody else has noticed this but I'm not seeing the comment. I'd suggest the OP starts again, shoots a scene in daylight, then the same scene at night with the same aperture and ISO, same focal length, manual focus, stable tripod - in other words the only variable is the light (and the shutter speed of course). Then they may be able to narrow down the problem. No! that was taken with a 50mm f1.8. I cropped the 100% from the original image and pasted there just to compare with original one in the comments from M Chapman above. Link to comment Share on other sites More sharing options...
MDM Posted June 24, 2017 Share Posted June 24, 2017 I just had a look at DxO and that 55-250 is a pretty poor lens in terms of sharpness, certainly way off professional quality. There is no Sigma 17-55 (OP's description), it's a 17-50 (as in the EXIF data) and is certainly better but is not great outside a narrow range of apertures and focal lengths. In answer to the title of the post, the answer is NO, you don't have to spend a fortune on a camera to get professional quality but you do have to choose your lenses carefully and use them within the range at which their performance matches professional quality lenses. Developing sound shooting and post-processing technique is most important. Link to comment Share on other sites More sharing options...
In my view Posted June 24, 2017 Author Share Posted June 24, 2017 How about someone sharing a picture taken under similar lighting which they think will pass QC? Link to comment Share on other sites More sharing options...
MDM Posted June 24, 2017 Share Posted June 24, 2017 1 minute ago, In my view said: No! that was taken with a 50mm f1.8. I cropped the 100% from the original image and pasted there just to compare with original one in the comments from M Chapman above. Ok my mistake. There was no EXIF in that file. But image 2 was taken with the 55-250, Given that the 50mm 1.8 is an excellent lens, then your technique and/or post processing is very questionable as that image is pretty awful if that is really 100% rather than 200 or higher. Your kit should be capable of way better than that so something is seriously wrong. I would suggest you try what I suggested - shoot the same scene in daylight and night to narrow down your problem with whatever lenses you use. Link to comment Share on other sites More sharing options...
M.Chapman Posted June 24, 2017 Share Posted June 24, 2017 43 minutes ago, spacecadet said: True but my RAWs look pretty soft before default sharpening. Yes mine do too, as they do from many cameras with an AA filter. If we have the RAW, at least we can load into LR, which will apply sensible defaults, and make comparison with our expectations, safe in the knowledge that no other processing has gone on. Link to comment Share on other sites More sharing options...
spacecadet Posted June 24, 2017 Share Posted June 24, 2017 That's rather further than I'd go to answer a forum query. Link to comment Share on other sites More sharing options...
MDM Posted June 24, 2017 Share Posted June 24, 2017 Something is not adding up here with what the OP says. Image 35461416676_105ff0c1d5 is supposed to be a 100% crop shot with a 50mm lens (no EXIF in this file) and the building is larger than 100% crop from image 35463983945_46ab628a12 of the same building shot with a 55-250 (from EXIF). The shots were clearly taken from the same point so this is impossible. I think the last image ( 35461416676_105ff0c1d5 i) is a larger than 100% crop - probably 200% - which is why it looks so bad in terms of sharpness and general quality. Link to comment Share on other sites More sharing options...
Inchiquin Posted June 24, 2017 Share Posted June 24, 2017 1 hour ago, In my view said: How about someone sharing a picture taken under similar lighting which they think will pass QC? I posted one the other day that did pass QC. Here are some more, all hand-held BTW: Alan Link to comment Share on other sites More sharing options...
M.Chapman Posted June 24, 2017 Share Posted June 24, 2017 1 hour ago, spacecadet said: That's rather further than I'd go to answer a forum query. Good point. Link to comment Share on other sites More sharing options...
wiskerke Posted June 24, 2017 Share Posted June 24, 2017 2 hours ago, In my view said: How about someone sharing a picture taken under similar lighting which they think will pass QC? With a 55mm - not with a Canon though. wim Link to comment Share on other sites More sharing options...
M.Chapman Posted June 24, 2017 Share Posted June 24, 2017 25 minutes ago, wiskerke said: With a 55mm - not with a Canon though. wim Wonderfully sharp (even into the corners - very good lens), and there's minimal noise. But, do you have any concerns about the "edge/effects artefacts" in the sky around the chimneys, aerials, weather vanes? Maybe they are introduced by jpeg compression? They are barely noticeable, but they do extend for quite a few pixels into the sky. Link to comment Share on other sites More sharing options...
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