Commons talk:Featured picture candidates

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Cleaning lens[edit]

Dear Friends,

Yashica Mat 124 G lens 80mm 3.5, before (left) and after (right) to clean 30 years of oil

I recently received a camera in excellent condition, however, the lens is stained by something (maybe oil). I spent a day trying to clean it using hot water, alchool and continuous polishing, however, the result is not totally clean.

My specific question is, what could I do to clean this lens?. Thanks --The Photographer 13:38, 2 April 2018 (UTC)

Not all kinds of substances/dirt are soluble in water and alcohol, there are those that can only be dissolved in organic solvents like chemically clean gasoline (not sure what name that is sold under in Canada). You should use something like that too. Also see: Solvent. -- Cart (talk) 14:08, 2 April 2018 (UTC)
Cart What do you think about Naphta Coleman?. Thanks --The Photographer 16:13, 2 April 2018 (UTC)
That doesn't look like it's pure enough. The Naphta (petroleum) I'm thinking of is highly purified and comes in small bottles sold in hobby stores or pharmacies. It's sometimes used by stamp collectors to clean stamps since it doesn't harm the stamps. Maybe someone living in the US or Canada knows a brand. -- Cart (talk) 16:38, 2 April 2018 (UTC)
If it's greasy acetone might do the trick. That's the stuff nail polish remover formerly consisted of. You should be able to get a small bottle of it at the pharmacy (you won't need much). But be careful, as it easily dissolves most kinds of plastic and paint as well. And wear gloves. --El Grafo (talk) 12:51, 4 April 2018 (UTC)
I wouldn't let acetone near any of my lenses. The fumes alone can damage the plastic parts surrounding the lens. One drop or splatter in the wrong place and the threads (hilos?) might be ruined. -- Cart (talk) 14:26, 4 April 2018 (UTC)
ACK. Given the age of the Yashica Mat, I was assuming that what we see on the picture is pure glass and metal. If the black parts are plastic, acetone is probably not a good idea. Also no idea what it would do to lens coatings if there were any. That's really a last resort option – acetone is nasty stuff. --El Grafo (talk) 15:17, 4 April 2018 (UTC)
The black part is Metal and I have Acetone with me in this moment, Gasoline pure or Gasoline light (whatever) is very difficult to find. I want wait to read anothers opinions because there is no way back. Please guys help me with this issue. --The Photographer 00:30, 5 April 2018 (UTC)
Looking at the photo again: Are you sure that it's actually dirt on the surface of the lens? Sometimes lens elements that were glued together to form a lens group start separating decades later (google e.g. "balsam separation"). If that's the case, you might be out of luck … --El Grafo (talk) 15:29, 5 April 2018 (UTC)
El Grafo, This looks at least partly like fungus which has destroyed either the cement (probably en:Canada balsam) between lenses or the coating or both. I am in Canada, maybe it is easy to find this Canada balsam, please, could you guide me in some method to fix it, it is a camera that also has a sentimental value. Thanks --The Photographer 00:25, 6 April 2018 (UTC)
The Photographer, from what I've read, if it's really the cement that has the problems I'd recommend to either give up (and maybe find a replacement part) or hand it over to a professional. In order to re-cement the elements you would have to get them apart first, and that seems to require a heavy-duty solvent. You may or may not want to read this thread on Pentaxforums – acetone is like honeyed milk compared to some of the stuff they're talking about there :-( --El Grafo (talk) 12:08, 6 April 2018 (UTC)
El Grafo I was carefully reading the forum link that you sent me and I have managed to buy all the ingredients including the Canadian balsam. Finally, I'm a little afraid of damaging this lens, however, lens repair is absurdly expensive and nobody sell this lens on ebay/amazon/kijiji/etc. I will try to do it with this manual, what do you think? --The Photographer 02:14, 7 April 2018 (UTC)

Portrait photography[edit]

Hi, I am a bit sick of people making silly comments about depth of field being too shallow in portrait photography. A shallow depth of field is feature, and that's how good portraits are made. See basic courses online: Normally f/2.8 and wider are the best, but for longer focal lengths, you can use up to f/4.0., [1], [2], [3], [4], etc. Please learn the basic techniques before voting. Thanks, Yann (talk) 13:40, 21 April 2018 (UTC)

Yann Whoi is commenting it?, it's a very basic rule. --The Photographer 13:48, 21 April 2018 (UTC)
Yann is angry with me for 'opposing' at this FPC nom and should say so up front intead of making insinuating comments. In another recent nom, f/4.0 was used and no one complained about the DoF being too long or against the rules of basic portrait photography then. (Or f/8.) --Cart (talk) 14:48, 21 April 2018 (UTC)
Well, the f-numer is only a part of the truth in terms of DoF. f/5.6 will have a different DoF depending on the focal length, 30 mm will have a poorer DoF than 80 mm, so that's also important. That's why the boy face and the soccer player look better than the painted face. Poco2 15:32, 21 April 2018 (UTC)
Thanks Poco for that info, I shall read up more on lenses. This little incident is exactly why people are more comfortable just avoiding to vote than speaking out in an 'oppose'. If you do so, you risk being dragged out here for a public flogging and be told that you don't know basic photography techniques. I could take offense for being told such a thing, but I'm pretty sure that Yann just said that in the heat of the moment. --Cart (talk) 17:09, 21 April 2018 (UTC)
Knowing him (I also had the pleasure in person) I am sure about that, too :) Poco2 17:15, 21 April 2018 (UTC)
I don't believe that a shallow DoF is necessary to make a good portrait. It always depends on the respective photograph. You can create a wonderful portrait at f/11 and a bad & messy looking one at f/1.4. So regarding the photo Yann is referring to I don't think it's worth being featured (I personally don't like the painting, the focus is not really on the eye and some other issues) but I wouldn't say DoF is an issue here. --Code (talk) 19:10, 21 April 2018 (UTC) P.S.: I think neither this nor that photo should have been promoted FP as both suffer from visible motion blur (while the DoF is perfectly ok IMO).
Code, what you say makes perfect sense. If applied at the right "starting point", a shallow DoF can be quite enough. Place it wrong, and it looks like you should have increased it. It is possible that the photographer of the face paint shot used auto focus instead of pinpoint focus and therefore it landed on the finger and nose. --Cart (talk) 19:33, 21 April 2018 (UTC)
Poco see Wikipedia DoF. "for the same subject magnification and the same f-number, all focal lengths for a given image format give approximately the same DOF." For example, on a FF camera, 100mm lens, f/4, subject at 3m gives DoF of 0.21m. You get the same DoF in a 50mm lens at 1.5m distance. And the same DoF in a 25mm lens at 0.75m distance. You have to move closer to get the same subject size. While the DoF is the same in all three, the telephoto will include less background than the wide-angle, so it will often appear less busy, but both are just as "out-of-focus". The problem that portrait photography is usually trying to solve with shallow DoF is to isolate the subject from the background and to avoid the background becoming a distraction. There is nothing in portrait photography that encourages the front of the nose or the ears to be out-of-focus. Nor, for a photo where the subject is facing the camera, is there anything that makes it desirable, never mind acceptable, for only one eye to be in focus. These things are all negative consequences of the photographer trying to isolate the background. For a studio photo, it is really up to the photographer to ensure their background is plain and neutral and far enough behind the model for it to be out-of-focus, and then they can use whatever aperture they want. Obviously, for a smaller aperture, they need a more powerful light, which could be a technical problem. For a photo of face painting, where the whole head and neck is painted, I can't understand why you wouldn't want all that to be in focus. The choice of focal length in that image is untypical (equivalent to 50mm full frame), and will exaggerate the model's nose and chin and head curve, compared to a more typical portrait focal length (85-135) -- and this is a result of having to be closer to the subject, rather than a property of the lens focal length or optics.
I agree that we often don't review portraits very well, as our pixel-peeping UI lets us too often focus on parts of the image rather than the whole. And sometimes the shallow DoF is just fine, and we don't need the sort of focus-stacking-front-to-back-sharpness obsession we see some voters apply everywhere. -- Colin (talk) 11:00, 23 April 2018 (UTC)
In my opinion the amount of DoF necessary in a portrait depends on the portrait itself. That painted face draws the viewers interest to every part of the face that has color painted on. The viewer wants to examine the whole painting on her face, so it needs to be sharp from at least her middle finger to her ears. When I shoot "business portraits" in conjunction with a studio setup and flash lights I mostly set my f-Stop to 11 to get the face and the visible part of the clothes worn completely sharp. The mentioned portrait of Kristina Inhof was shot with the sun just going down so I did not want to close the aperture too much and keep the ISO at a reasonable low level. Code, yes there is some motion blur. This sometimes becomes visible with my D850 even with the shutter speed being more than twice of the focal length, but you are the first one to pixel peep that much to forget the fact (25 pro-votes in five days are quite factious) that overall the image seems to be quite good. btw: You can always nominate that image for delisting. --Granada (talk) 11:42, 23 April 2018 (UTC)
  • The funny thing, given how this thread started, was that when I made my vote on the face paint photo, I had in mind an illustration from one of the very first photography books I've ever read. (Yes, I have read such! ;-) ) In the section on portraits there were two photos showing when a shallow DoF should be used in portraits and not. The "not-photo" was a woman in almost exactly the same position as the face-painted woman, only she had a microscope in front of her face instead of a hand. Of course the best DoF depends on the photo and situation. --Cart (talk) 13:07, 23 April 2018 (UTC)
  • @Granada: Well, my words above might have been a little bit harsh and I apologize for that. It's a good picture overall and you're right that one shouldn't pixelpeep that much. --Code (talk) 17:55, 24 April 2018 (UTC)

You withdraw your nomination, then could you archive it too ?[edit]

Hello everyone,

About 25% of the FP nominations here are withdrawn. One candidature out of four is interrupted by their nominator. But for now the FPC bot isn't programmed to archive any withdrawn FPC (perhaps because a few of them get reconsidered to finally follow the normal voting period).

As a consequence of these frequent abandons, the list can become crowded with a lot of unused templates remaining active on the main page.

To get rid of a withdrawal, the only way is to manually close the FPC in 4 simple steps : Commons:Featured_picture_candidates#Archiving_a_withdrawn_nomination.

Closing one of them is not a hard work, but if everyone entrust this task to the few volunteers, then the quantity makes a lot of repetitive work for those who are not responsible for these failures.

Thus, I would suggest that each participant takes their responsibility, and once the verdict of a necessary withdrawal is taken, then closes + archives their own nomination.

This will make tasks more balanced in the group. Thanks ! -- Basile Morin (talk) 03:56, 24 April 2018 (UTC)

Hi Basile! Thanks for that hint! I always feel just not eligible closing FPC bot results regarding my own images no matter of the result be it a withdrawal, a "featured" or a "not featured. --Granada (talk) 05:57, 24 April 2018 (UTC)
Thanks Basile! Granada, closing noms is not something you need to be "eligible" for. Learning/reading about how to close noms and also sorting your photos in the right place in the FP gallery and the right FP caregories is in fact much easier than figuring out how to make a nomination. Should you make a mistake, it's no big deal, the Usual Cleanup Crew will take care of it. You'll soon get the hang of it. On this site, I sometimes think it is like living with a bunch of teenagers who are very happy to pull out and use everything, but less good at cleaning and picking up after themselves. --Cart (talk) 06:52, 24 April 2018 (UTC)
There are so many different people nominating and withdrawing that I don't think it reasonable for them all to have to learn the procedure. And I don't think the teenager criticism is entirely fair either. I don't expect those who run the Main Page to come along and complain that us photographers don't help out enough. When I ran the process at Photo Challenge, nobody ever volunteered to help until I took a wikibreak, and I don't have a problem with that -- I never asked for help. Most Featured X processes on wiki are administered by a few who either self-volunteer or else are elected by the community. It is pretty rare that everyone helps out.
It sounds like the FP bot needs an overhaul. I know I get frustrated that it screws up the file-description page by inserting the award before the geotag, which messes up the appearance. It doesn't sound hard to get it to spot a withdrawn template. Perhaps we can list the defects here and make a request on the VP for someone to volunteer to fix it, or write a better one. That's the better solution than doing repetitive work and complaining about it. -- Colin (talk) 09:49, 24 April 2018 (UTC)
Yes, an overhaul of the FP bot is long overdue. Closing and archiving withdrawn nominations is one of the missing features. The current maintainer said that he won't do any change, but he welcomes patches. Or would it better to rewrite from scratch? Anyway we need a coder... Regards, Yann (talk) 10:16, 24 April 2018 (UTC)
Agree that a better Bot would be the best thing, but until that happens I don't see why people can't help out and I don't think it's wrong to ask for it. Of course we don't expect every newbie and casual FPC visitor to know everything, but there are plenty of regulars who know how things work. I like this site, I care for it and about it and I like it to function. --Cart (talk) 10:41, 24 April 2018 (UTC)
I had a look at the archive, curious about all the withdrawn noms to see if there was anyone frequently withdrawing. But I had to give up listing all the totally different names. So for 20 withdrawn candidates to be self-cleared up you'd need nearly 20 people familiar with the process and who need supervising and cleaning up when they screw up. Sounds like a terrible rate-of-return, and having folk who only do it once in a blue moon is asking also for more issues. Of course it isn't wrong to ask for help in a positive way. I think this is similar to the nonsense at QIC where nominations are heavily limited solely because reviewing is such a joyless PITA that they can't get through the quantity. Encouraged that The Photographer might be able to help with both. -- Colin (talk) 12:35, 24 April 2018 (UTC)
I have faith in that people can read and learn. Face-wink.svg --Cart (talk) 13:10, 24 April 2018 (UTC)
FYI, I'm working on a user script to archivate automatically the nomination. Also, I allready created a plugin to hide your Flickr2commons uploads and to vote on QIC. --The Photographer 10:58, 24 April 2018 (UTC)