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Thread: The lens that never was or price of desperation.

  1. #1

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    The lens that never was or price of desperation.

    Here is a part most folks here did not know about before i bought my new 50mm 1.8 lens. Some desperation for autofocusing lead me to buy a very cheap Tamron 28-200lens. It autofocuses alright but no matter how hard i try, the pictures always come out whitish....
    Have a look:
    The lens that never was or price of desperation.
    Shot at f/8, 1/125, ISO 200 at 28mm.

    Look at the upper left corner. Now, i'm not yet a pro but trust me, this shot wasnt meant to be like this. A couple more i shot indoors were more disastrous. It just shows some whitish thing like a flare(but not the lens hood non-use kinda flare)....for the picture i just posted, assuming i focused correctly(don't worry about my composition for now please), with some time trying to fix it in lightroom...what do you think is wrong with this lens?

    And oh, it was bought used and dirt cheap from an old photographer. An old friend(photog too) help verify it before sending it down to where i live. Now, i'm not one to cry over past issues(less than $50 in this case) but i just wanna know. And could the lens be ever useful for anything else apart from a reference point in my biography under a chapter called "Desperate choices" or "The expensive price of cheap decisions"...pun intended of course.

    Seriously, what do you think?

  2. #2
    Moderator GrumpyDiver's Avatar
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    Re: The lens that never was or price of desperation.

    Ife - two thoughts:

    1. Are you using a clear filter, like a UV for these shots. If so, this might be the cause, cheap filters don't have anti-reflection coatings and can cause this issue. If you have one, remove it and take a shot; if this goes away, problems solved; and

    2. Are the front and back lens elements clean. Dirt on the lens can cause internal reflections too. Try cleaning these lens elements.

  3. #3
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    Re: The lens that never was or price of desperation.

    In taking the photo into LR and blowing it up 100% I'm seeing more of a focus problem it's just not sharp and over all what I call, it's flat having no punch to it. Maybe it's just me but I'm not seeing any flare or blow out spots. Hope you don't mine here it is again after LR, did not spent much time on it.

    The lens that never was or price of desperation.

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    Re: The lens that never was or price of desperation.

    Hi Ife,

    Long zoom lenses are tempted to be soft in corners, especially in wide focals. Tamron engineers are well known for their "reverse engineering" ( take the original from different producer, and "rebuild" the lens). Sometimes works, sometimes not.

    http://www.photographyreview.com/cat...2_3128crx.aspx

    Above a link to a different "review site". As you may see, many opinions pros and cons, and there are people who complain about the same behaviour.
    I will suggest you to shoot more with it, to see it strenght and weakness, and become friendly to each other. Try a "brick" test for the most focal distances, to see where is ok and where not. Keep in mind those focals, and try to avoid those compositions who are not suitable for you and your gear ( i.e. if there are soft corners at 28mm, try to use it more outdoor, a blue cleen sky will minimize that issue).

    Hope it helps,
    Leo

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    Re: The lens that never was or price of desperation.

    I also had a play in LR with it. A good minute and a half. Looks to me that there is very low contrast. Some of this may be attributed to the issues mentioned by Manfred. Some possibly the angle to the light and some likely to the lens. The main thing I did here was to boost the contrast heavily.

    The lens that never was or price of desperation.

  6. #6
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    Re: The lens that never was or price of desperation.

    Now even to me, a novice, the contrast boost makes a real change. I learnt something here today.

  7. #7

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    Re: The lens that never was or price of desperation.

    Oh my gosh! Contrast? This is amazing....I need more PP and PPP(PP Philosophy). I almost can't recognize the image. Gentlemen, I'm downloading this. Thanks a lot.

    At the moment, I'm on a sick break and don't have the lens with me but I will further clean, test it and remove the filter. Since my gurus are around, lemme give a tiny info on the lens...if you view it at certain angles(the lens itself, from the front), it shows some bluish/purple coloration or patches(not the normal cool blue a lens looks like). This one is more like: you know when you wash a windshield(car's) and while rinsing, just before you dry it...some type of coloration you see...

    It just shows in a few areas.

    I can't wait to get back in health and remove the filter I put. Er...erm....er...well, its a plain-looking highly-cheap, so-called uv-filter.

    I just wish its rectifiable....oh boy, my swelling gear. 50mm, 70-300, 28-200. Hello, my old 18-55.

  8. #8
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    Re: The lens that never was or price of desperation.

    It looks almost like it's been shot through glass to me so the filter might be the problem but it's rare for a zoom lens with that sort of range 7:1 to be what would normally considered as good. It is possible to cope with lenses that do that sort of thing. I tone mapped it fairly extremely and then applied a moderate amount of sharpening. As these 2 operations were pretty obvious I then added a little blur. I suspect you didn't sharpen the image a little after reducing it's size for the web so maybe I should have done that 1st, Another explanation for the look of the shot would be relatively bright light that has been cropped out of the shot. Anyway here is my take on it.

    The lens that never was or price of desperation.

    Looking now on the web maybe a little too much blur.
    -

  9. #9
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    Re: The lens that never was or price of desperation.

    Ife,

    How did you have your shooting parameters set up when you took this shot. It looks like the conditons were fairly bright, although the light might have been diffused a bit which accounts for the lack of harsh shadows...

    If you were using ISO 200 in bright sun conditions, your correct exposure might have been 1/800 at f/8... In hazy sun conditions you would have needed a bit more exposure, say 1/400 second at f/8. It seems that your image might have been a bit over exposed by shooting at f/8 using 1/125 second with an ISO of 200...

    Your image might have had several problems, each compounding the other... Over exposure, use of a cheap filter and the lack of a lens hood (I am suspecting that you did not use one)...

    You can modify the exposure problem and remove the cheap filter which will hopefully improve your image...

    One way of mentally checking your exposure is to use the "Rule of Sunny 16". The correct exposure of a "normal" subject would be the reciprocal of the ISO you are using af f/16. In other words if you are using ISO 200 the correct exposure would be around 1/200 second @ f/16; or 1/400 @ f/11; or 1/800 @ f/8...

    Subjects of different brightness and subjects in other lighting conditions will require different exposure. However, if the exposure you are using varies a great deal from the "Rule of Sunny 16" you might just be using an incorrect exposure. Despite the fact that many experts recommend the use of manual exposure, I have seen more bad exposures from manual exposure mode than from Programmed or Aperure priority...

    Rule of Sunny Sixteen: http://en.wikipedia.org/wiki/Sunny_16_rule

    Regarding a lens hood. I always recommend using one, especially when shooting outdoors. You can fabricate a lens hood from some cardboard type material - preferably black or with the capability of being painted black...

    http://www.lenshoods.net/

    If you decide to purchase a lenshood, the Chinese knockoffs, available on eBay and Amazon.com, are perfectly good and cost a fraction of what the OEM manufacturers charge...

    One more thing: sometime less expensive lenses which have a great focal range are less efficient at either the shortest or the longest focal lengths. Your lens "may" produce better results at 35mm to about 150mm more or less. I cannot vouch for that but, it may be worth a try...
    Last edited by rpcrowe; 19th November 2012 at 04:53 PM.

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    Re: The lens that never was or price of desperation.

    Hi Ife,

    Technically the problem is "lack of contrast", but you don't want to try and fix that with a contrast control because as much as that will make the shadows darker, it'll also make the highlights brighter. Fundamentally, what you have here is an exposure issue (it's slightly over-exposed) which means that the black point needs to be adjusted to stretch the tonal range of the shot. A couple of things are also "adding to the challenge" ...

    1. You have a lot of ambient light entering the scene behind the subjects (back lighting), and

    2. When you have dark-skinned folks you can't get as aggressive with the black clipping point because you'll lose too much detail in their skintones.

    So in other words, you need to process a shot like this carefully (I might add that for the location you chose, a little fill flash would have gone a long way, and that the lens probably has an inherentl contrast issue) (I'm afraid that Tamron don't have the greatest reputation in the world when it comes to quality).

    Anyway ...

    ... here's a retouched version

    The lens that never was or price of desperation.
    Last edited by Colin Southern; 22nd November 2012 at 11:24 PM.

  11. #11

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    Re: The lens that never was or price of desperation.

    Hello everyone, Colin is such a big liar. He did not retouch the image i posted. You know what he did? I'll tell you. He secretly came to Nigeria, rounded the folks together, got those folks to wear same clothes and took the shot again with his more-impressive gear. If the idea is to make me look bad Colin, it won't work.

    Absolutely kidding! Of course you know that. I can not believe this. What exactly did you do to the image? A step-by-step play will be hugely appreciated. Lightroom? Elements? Photoshop? Please talk to me.

    Thanks so so much.

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    Hey - not so much of the "big" thank you!

    To be honest, the adjustments come from experience in doing them - no shortcuts I'm afraid - it just takes understanding of what the issues are and knowing how to fix them.

    In this case the top left corner is washed out because its over-exposed - so I started with a GND filter to knock back that region. Next up, I reset the clipping points (actually INCREASING the exposure slightly overall) (which doesn't worsen the top left because of the GND and raising the black clipping point.

    Next up is a brightness adjustment to kill flatness in the midtones.

    Small clarity adjustment (shouldn't have been necessary, and generally not advisable with people, but needed in this case.

    Open in Photoshop (all the above was in ACR), then burn the top left area (shadows) to increase contrast, and dodge (shadows) over the faces (just a touch).

    Sharpen / Frame etc.
    Last edited by Colin Southern; 22nd November 2012 at 11:26 PM.

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    Re: The lens that never was or price of desperation.

    Cheap objects do not come cheap without a reason. I had similar experience with a Sigma lens some 20 years ago. The 200mm zoom objective never seemed to get sharp images. I have given up buying used camera equipment.
    grt. Michel

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    Re: The lens that never was or price of desperation.

    Quote Originally Posted by Colin Southern View Post
    Hey - not so much of the "big" thank you!

    To be honest, the adjustments come from experience in doing them - no shortcuts I'm afraid - it just takes understanding of what the issues are and knowing how to fix them.

    In this case the top left corner is washed out because its over-exposed - so I started with a GND filter to knock back that region. Next up, I reset the clipping points (actually INCREASING the exposure slightly overall) (which doesn't worsen the top left because of the GND and raising the black clipping point.

    Next up is a brightness adjustment to kill flatness in the midtones.

    Small clarity adjustment (shouldn't have been necessary, and generally not advisable with people, but needed in this case.

    Open in Photoshop (all the above was in ACR), then burn the top left area (shadows) to increase contrast, and dodge (shadows) over the faces (just a touch).

    Sharpen / Frame etc.
    Those are truly excellent adjustments Collin. : I'm having trouble matching them. I have to use selection though and intend to continue to see just how the boundary problems I have seen in many shots are avoided. Pity the shot didn't crop up in the raw jpg debate. I have the skin tones correct but a little too shiny and also the plastic canopy - boundary problems. The wall is easy. The bit of roof a lot less so.

    I can't help feeling that the problems in the shot are down to a type of flare. Something bright washing everything out in the shot via internal lens reflections. The shot may have been developed from raw though so hard to say. Similar effects might be obtained developing from an inappropriate exposure and trying to cram the lot into a jpg.

    These sort of end results can be seen in the camera with magnified preview. The answer may well be to under expose and rely on always being able to restore the dark end of a shot. The other option is too pop up the flash and use that to even out lighting. In built flash guns are weak but become far more effective if the iso is pumped up some what.
    -

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    Re: The lens that never was or price of desperation.

    Quote Originally Posted by ajohnw View Post
    Those are truly excellent adjustments Collin. : I'm having trouble matching them. I have to use selection though and intend to continue to see just how the boundary problems I have seen in many shots are avoided. Pity the shot didn't crop up in the raw jpg debate. I have the skin tones correct but a little too shiny and also the plastic canopy - boundary problems. The wall is easy. The bit of roof a lot less so.

    I can't help feeling that the problems in the shot are down to a type of flare. Something bright washing everything out in the shot via internal lens reflections. The shot may have been developed from raw though so hard to say. Similar effects might be obtained developing from an inappropriate exposure and trying to cram the lot into a jpg.

    These sort of end results can be seen in the camera with magnified preview. The answer may well be to under expose and rely on always being able to restore the dark end of a shot. The other option is too pop up the flash and use that to even out lighting. In built flash guns are weak but become far more effective if the iso is pumped up some what.
    -
    Hi Johhn,

    I didn't need to use any selections; I think folks just need to forget about "putting band aids" on the image and take a step back. For sure, the image as original presented has a number of challenges, but they're also relatively easy to fix.

    Start by normalising the image with a GND from top left; in essence this is no different to a shot in the studio where the part closest to a light produces higher levels of reflected light:

    The lens that never was or price of desperation.

    Usual ACR Stuff

    The lens that never was or price of desperation.

    Levels adjustment in PS

    The lens that never was or price of desperation.

    Burn (Shadows, 4%) mostly over top left, but elsewhere as required

    The lens that never was or price of desperation.

    Dodge (Shadows, 4%) over faces - particularly left gent

    The lens that never was or price of desperation.

    Sharpen USM 300% @ 0.3px, border etc

    The lens that never was or price of desperation.

    With regards to the initial problems - I'm still not thinking "flare" so much as "crappy lens" - uneven lighting - and processing issues. If I were shooting that scene I'd reposition to avoid the shaft of light that illuminates the top left area (keeping in mind that the blue thingee is also reflecting a lot of energy back into the sensor). I'd then under-expose the scene by about 2/3 of a stop to shift the blacks down and give a better exposure to the background, and then hit the subjects with some fill flash (preferably up high, angled down).

    I don't think the lens is helping (poor contrast), but it's only part of the problem.
    Last edited by Colin Southern; 24th November 2012 at 03:51 AM.

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    Re: The lens that never was or price of desperation.

    I think I'm going have to try and persuade the author of Fotoxx to add gradient filters but it has something called a brightness ramp. Not something I have used before as no need. It's a brightness adjustment presented as a cross that maps to the entire image so that gradients can be applied in many ways and or directions. The "cross" lines can have any shape.

    Thanks for the adjust to "studio type shot" tip Colin. Like you I would normally try and expose for acceptable highlights and maybe use a flash. That adjustment is a little like another I have mentioned - blurring the background a little. Both make subjects stand out. Similarly we expect things to dim down with distance. Artists make a lot of use of both techniques. Selection does work out when adding blur but it can also be done with the lens but the blur should still leave a recognisable background. It needs to be subtle These days people just seem interested in extremes - extreme bokeh etc

    It's unusual for modern lenses to show the effect this shot seems to. One of the major advances in optics has been to account for internal reflections, that and better glasses which effectively just means less glass for the same level of performance. One other possible cause is very dirty optics or poor previous cleaning that has left a lot of significant scratches - those would probably need and eye glass to be seen easily. Odd marks hardly have any effect as the whole area of a lens contributes to the image. Cleaning optics is a tricky subject and always causes a lot of debate.

    -

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    Re: The lens that never was or price of desperation.

    Quote Originally Posted by ajohnw View Post
    I think I'm going have to try and persuade the author of Fotoxx to add gradient filters
    Or just start using Photoshop under Windows like most other folks do

    Thanks for the adjust to "studio type shot" tip Colin. Like you I would normally try and expose for acceptable highlights and maybe use a flash.
    In the studio often it's a compromise between a light being close enough to improve softness, but far enough away to give sufficient light depth or field. When the light gradient is too steep from a light being too close, the GND tool works wonders - very quick and easy to apply. One can also use 3 or 4 of them to simulate a vignette as well (useful when the different edges need different treatments (eg a close crop of a head shot where one wants to de-emphasise the hair at the back & top of the head, but not the face)

    It's unusual for modern lenses to show the effect this shot seems to.
    I'll have to take your word for it -- I only use L-Glass these days

  18. #18
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    Re: The lens that never was or price of desperation.

    The last time I really used windows was windows 95. Around then I added Linux. Later I did load up XP and Linux so that I could run either but found that I hardly ever used XP. Has to be admitted that these days I could run most of the applications I use under windows or mac but not Fotoxx and I really would miss that. Change is unlikely but I wouldn't entirely rule it out. Linux has more users these days than ever but the people who write the desktop code have this habit of throwing the lot away and starting again periodically = bugs which can make people wonder - there are other desktops about though.

    I just had another go using the brightness ramp. Much closer and it's a useful shot for getting to know how best to use it. It too can vignette and there is a separate lens correction curve for that as well. 2 things I would like adding is black point adjustment and ca correction. One of the advantages of open source is that if I ask and explain why it might actually get done. That's what happened with my Hanvon graphics tablet I asked the guy who wrote the driver to make some changes - he didn't but suggested a cure within a couple of days. He started to modify the driver and then found that there was another way of solving the problem buried in Linux. Unlike windows at that sort of level there often is. Mac's well exceeding strong rumours suggest they are running a marginally revamped version of Linux maybe with their own desktop code.

    -

  19. #19

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    Re: The lens that never was or price of desperation.

    Quote Originally Posted by ajohnw View Post
    The last time I really used windows was windows 95. Around then I added Linux. Later I did load up XP and Linux so that I could run either but found that I hardly ever used XP. Has to be admitted that these days I could run most of the applications I use under windows or mac but not Fotoxx and I really would miss that. Change is unlikely but I wouldn't entirely rule it out. Linux has more users these days than ever but the people who write the desktop code have this habit of throwing the lot away and starting again periodically = bugs which can make people wonder - there are other desktops about though.

    I just had another go using the brightness ramp. Much closer and it's a useful shot for getting to know how best to use it. It too can vignette and there is a separate lens correction curve for that as well. 2 things I would like adding is black point adjustment and ca correction. One of the advantages of open source is that if I ask and explain why it might actually get done. That's what happened with my Hanvon graphics tablet I asked the guy who wrote the driver to make some changes - he didn't but suggested a cure within a couple of days. He started to modify the driver and then found that there was another way of solving the problem buried in Linux. Unlike windows at that sort of level there often is. Mac's well exceeding strong rumours suggest they are running a marginally revamped version of Linux maybe with their own desktop code.

    -
    Horses for courses I guess John, but I do seem to find a lot of Mac and/or Linux folks so "entrenched" in their positions that I'm convinced that it's driven far more by a "bee in their bonnet" about the likes of Microsoft and Adobe than it is due to any real-world technical advantage (the term "rebels in search of a cause" frequently comes to mind!

    I often hear of how "bad" windows is - how "evil" Microsoft is - and how "over-priced" Photoshop is etc ... and yet for me, Windows is fast and stable - I don't have any issues with Microsoft - and Photoshop just keeps getting better and better (for around a dollar a day to stay up with the very latest). I use a Wacom tablet - and it just works without having to work with anyone regarding drivers etc. All just seems too easy for me to want to do it any other way. Perhaps it's just me.

  20. #20
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    Re: The lens that never was or price of desperation.

    I'm basically a design engineer Collin - work in that line has got scarcer and scarcer in the UK over the years so drifted into software on automotive ecu's. One aspect of shifting to Linux was using windows for something it's not really intended for all day long. I also know too much about window's innards however they seem to beavering away on fixing some aspects of that at the moment. Can't say as I have ever regretted the move and generally have a stable fast system although the desktop application I use, KDE, is some what processor hungry these days. I have run my current set up for just over 2 years. Support more or less stopped recently so I will probably upgrade shortly after Christmas. Support in this case means no more security upgrades and the inability to run the latest versions of a few applications.. In practice security upgrades may continue for a lot longer. Just about to run some and other updates as well.
    -

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