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Would it matter if the glass is marked or scratched? |
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05-15-2010
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#1
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.......sometimes i thinks
fixbones is offline
Join Date: Mar 2009
Location: Melbourne, Australia
Age: 31
Posts: 765
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Would it matter if the glass is marked or scratched?
Hi,
Most people like things to be nice and pristine.... me included.
However, i am currently shooting with a lens which i really like from the 1960s with spots and light scratches on the front element. It does not bother me and i don't think it has any negative impact on the final picture either (at least I can't see it).
Also, i think it'll be pretty darn hard to keep a lens scratch and spot free for 50 years unless it sees very minimal use.
Am i the only one????
Are all of you out there shooting through mostly unmarked optics???
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05-15-2010
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#2
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ɹoʇɐɹǝpoɯ moderator
back alley is offline
Join Date: Jul 2003
Location: canada
Age: 62
Posts: 35,104
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05-15-2010
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#3
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a.k.a. Mukul Dube
payasam is offline
Join Date: Sep 2005
Location: Delhi, India
Age: 62
Posts: 4,857
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I bought three lenses in 1975 and sold them, after much use, in 2005. No marks.
__________________
"Payasam" means a sloppy pudding. Little kids love it, and I'm a little kid with a big grey beard and diabetes.
Film: Leica M6, Hexar RF, Zorki 1C, Ultron 35/1.7, M-Hexanon 50/2,Elmarit 90/2.8, Hektor 135/4.5, Canon 100/3.5, Jupiter 8
Digital: Olympus E-300, E-510 and E-3 with 4 Zuiko Digital lenses
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05-15-2010
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#4
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.......sometimes i thinks
fixbones is offline
Join Date: Mar 2009
Location: Melbourne, Australia
Age: 31
Posts: 765
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backalley: Thats pretty amazing
My assumption is that surely there are still lenses out there which are less then perfect but still getting plenty of use.
Would you think less of your favourite lens if unfortunately it has picked up some marks here and there?
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05-18-2010
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#5
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Nikkor AIS
Nikkor AIS is offline
Join Date: Sep 2009
Location: Alberta
Posts: 803
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It makes not a single bit of difference at all. I told this story on the Nikon cafe but I knew one of the staffers (Dean Bicknell was his name)that was using a Nikkor 300 2.8 IF ED AIS that a chip in in the sizes of a lonnie in the front element. He used that lens for years and made cover after cover of the newspaper. If you have a deep gouge the best thing to do is not look at it and keep shooting. you could also paint so india black ink to minimize reflections.
Gregory
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05-18-2010
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#6
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Cookie Monster
dacookieman is offline
Join Date: May 2009
Posts: 182
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If you are a user, then no, it wouldn't matter as it does not affect your images.
However, if you are a reseller, then yes, it matters as it will affect the len's resale value.
Many people forget that these lenses are 30-50 years old, and expect the condition to be like as if buying new. Cheers.
Last edited by dacookieman : 05-18-2010 at 07:53.
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05-18-2010
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#7
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Tropics of MinneSnowta
Pico is offline
Join Date: Nov 2005
Location: Driftless Zone
Posts: 214
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It is damned certain that if a photographers work is no longer satisfactory, then it's not caused by a scratched front element. It's about the photographer - unless your work is strictly lens tests against rez charts. OH! And if it's about MTF - fugedaboudit! They are completely artificial, having nothing to do with real world work. Look into their refocus methods for each aperture.
Look to all the great work done with 'inadequate' lenses and be happy.
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05-18-2010
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#8
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Practitioner
Harry Lime is offline
Join Date: Nov 2005
Location: Here and there
Posts: 1,525
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Scratches and chips on the rear element are a far, far bigger problem than blemishes on the front.
But even with marks on the rear element it depends where they are located. A chip on the edge may pose no problem whatsoever, but a scratch smack in the center could spell trouble. Shooting a test roll under challenging lighting conditions is advisable.
A few scratches or wipe marks on the front element should not render a lens useless.
I've seen countless posts about people freaking out that their Summicron has a wipe mark on the front. Again, in my experience the internal haze that most of these lenses have accumulated over nearly 60 years in a far bigger problem.
Last edited by Harry Lime : 05-18-2010 at 12:17.
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06-01-2010
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#9
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Photon Counter
kossi008 is offline
Join Date: May 2008
Location: Dresden, Germany
Age: 46
Posts: 640
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Quote:
Originally Posted by Harry Lime
[...] but a scratch smack in the center could spell trouble. Shooting a test roll under challenging lighting conditions is advisable.
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Well, it could. But I've once borrowed my neighbor's Hassy, and the 80 mm had a big mother of a scratch right down the middle of the rear element. And guess what? Zero effect. Got me thinking... 
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06-01-2010
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#10
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Preserving Old Technology
Rob-F is offline
Join Date: Mar 2007
Location: secret midwestern underground bunker
Posts: 3,420
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I can agree with Harry that defects on the rear element are more serious than ones on the front. I can also say that your (fixbones) experience is pretty typical. Some of us have a favorite lens or two with some scratches; yet we don't mind using it, and find nothing wrong with the images we get. Once I tried a DR Summicron that had separations and haze. It wasn't easy to find anything wrong with the images it produced.
__________________
“There is hardly anything in the world that some man cannot make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey.”
--John Ruskin
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06-01-2010
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#11
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qu'est-ce que c'est?
crawdiddy is offline
Join Date: Oct 2007
Location: left of center
Posts: 2,092
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Quote:
Originally Posted by back alley
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Would KEH consider that lens UGly? Or is there a category below that?
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--Dan
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06-01-2010
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#12
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Registered User
Steve M. is offline
Join Date: Jun 2009
Posts: 1,981
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A scratched front element usually has nothing to do w/ lens sharpness. If you have a sample that is not so good, then it doesn't matter if it's pristine, it won't take optimal photos. On the other hand, if you have a good sample, then it can tolerate a lot of scratches before seeing any image degradation. Cleaning wipes are another matter, as they are probably more responsible for lowered IQ.
In the end, the only way to see if a lens is sharp or suffers from flare (from scratches on the front element) is to shoot some film through it, or look at it's digital files, and compare them to another sample.
I long ago realized that if you get a good lens, keep it, because there is absolutely no guarantee that an identical one is going to perform as good. This is especially relevant when dealing w/ 50 year old glass.
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06-01-2010
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#13
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Mister E is offline
Join Date: May 2010
Location: I <3 NCPS
Posts: 1,688
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Quote:
Originally Posted by Harry Lime
Scratches and chips on the rear element are a far, far bigger problem than blemishes on the front.
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For the type of shooting I do, a lot of shots into the sun I find the opposite to be true. When the mark is in the rear element then it doesn't cause added flare or a less of contrast. Even minor marks on the front element have caused lots of extra flare for me in the past. My 18/2.8D was absolutely trashed on the rear element and it made great pictures. The gouge looked like someone had taken a screwdriver to it:

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