Avoid uv filters

[kundalini]

Oh, you want science?

Let us postulate a pointed object capable of scratching the lens of your camera. A diamond ring, a nail suitably aimed, or whatever. Let us drop the lens from a height and in such as way as the energy available is sufficient to scratch the lens, but just barely. I think we can agree that for a suitable object this energy is quite low. That is, we need drop the lens from a mere inch or two of height.

All we need to do is demonstrate that the energy required to break the filter is greater than the energy required to scratch the lens glass.

I will now do this with a nail, applied firmly but not violently:

... there. I scratched the front element of my Nikon 50 f/2.0 with the nail and now..
... applying the same force to the 58mm UV filter I have in front of me I find that it is scratched, but NOT broken.

I invite you to perform the same experiment at home! I admit that my force measurements were a little ad hoc, you may want to rig a device which allows perfectly repeatable applications of the nail to the lens. Then ramp up until you have just barely achieved a scratch on the lens. Then apply that same force to the UV filter. If the filter neither breaks nor deflects sufficiently to contact the lens behind it, we're done.

I'd show you pictures but, well, they could be photoshopped after all. It's best if you run the experiment yourself.

yous funny. thanks for the laugh.

 

[BrianV]

I have a number of lenses that were saved by the use of protective filters.

Prove it.

I have a coated Zeiss 5cm F1.5 from 1936, from the test batch of coated lenses. I'm glad it had a filter on it. I have another Zeiss Sonnar from World War II looks like the Afrika Korp used it. Wish they had used a filter, but it was ~$100 in Leica Mount.

I suspect the 1936 lens would go for ~$1K or more, the 1945 lens could go to Focalpoint and be restored for $200. That's what they charge to polish and recoat a front surface, comes back like new. Well worth buying the Hot-Glass Summicron for $50. Front element looked like wax-paper, came back like new. So- nothing $200 will not fix.

 

[oldhippy]

[QUOTE=Buckster;



When someone invents "protection filters" that don't throw glass shards toward the front element on impact, cause zero reflections, Newton rings, flare or other assorted IQ issues, then we'll likely all join the protection crowd. Till then, it sort of reminds me of crossing ones' fingers in place of using a condom. Every time she doesn't get pregnant, you can say, "See? Crossing your fingers WORKS!!"





Speaking from experiance. No I didn't drop m lens and see a protective filter save it. But I tried the cross your fingers and she wont get pregnent thing. Now I am the father of 8 children. Really.
But getting back to the lens protection. I purchased a 70-300 nikon av g. The vendor said they would include a filter. After a month of shooting through this filter I noticed it was pealing. My point is why screw up your pics, with a cheap filter which, may or may not protect your lens. Ed

 

[Tee]

I live at the beach and photograph at the beach a lot sans UV filter. Not once have I ever had sand get in the lens. I can understand if someone is photographing dune buggy races, motorcross, etc but for the common shooter, a lens hood is sufficient. I'm much more content replacing a $30 lens hood than prying off a broken $15 UV filter that may or may not have saved the lens but most likely contributed to the cosmetic damage to the lens thus devaluing the lens.

P.S. Buckster- loved the image of Pittsburgh. :thumbup:

 

[Buckster]

I have a number of lenses that were saved by the use of protective filters.

Prove it.

I have a coated Zeiss 5cm F1.5 from 1936, from the test batch of coated lenses. I'm glad it had a filter on it. I have another Zeiss Sonnar from World War II looks like the Afrika Korp used it. Wish they had used a filter, but it was ~$100 in Leica Mount.

I suspect the 1936 lens would go for ~$1K or more, the 1945 lens could go to Focalpoint and be restored for $200. That's what they charge to polish and recoat a front surface, comes back like new. Well worth buying the Hot-Glass Summicron for $50. Front element looked like wax-paper, came back like new. So- nothing $200 will not fix.

I'm sorry, but I'm not catching the proof here.

Are you saying that these two lenses were used side by side and subjected to the same forces, conditions, weather, use, abuse, and so on, and the one with the filter had no damage but the one without the filter had damage?

If you (or anyone) is trying to make the case that if you put two lenses side by side facing a sandblaster, and one of them is wearing a filter, it will protect the lens, yeah, obviously. But that's not what we're talking about here. We're talking about protection in regular, everyday use, and the impact scenario from dropping it or it falling over while on a tripod are the real question.

That said, HOW does your story specifically provide evidence that a filter protects a lens from that?

 

[kundalini]

Oh, you want science?

Let us postulate ...... blah, blah, blah

Sorry, this is just too much fun on a Friday night.

sci·ence

/ˈsaɪ

əns/ Show Spelled [sahy-uh

ns] Show IPA
noun
1. a branch of knowledge or study dealing with a body of facts or truths systematically arranged and showing the operation of general laws: the mathematical sciences.

2. systematic knowledge of the physical or material world gained through observation and experimentation.

3. any of the branches of natural or physical science.

4. systematized knowledge in general.

5. knowledge, as of facts or principles; knowledge gained by systematic study.


pos·tu·late

/v. ˈpɒs

tʃəˌleɪt; n. ˈpɒs

tʃə

lɪt, -ˌleɪt/ Show Spelled [v. pos-chuh-leyt; n. pos-chuh-lit, -leyt] Show IPA verb, pos·tu·lat·ed, pos·tu·lat·ing, noun
verb (used with object)
1. to ask, demand, or claim.

2. to claim or assume the existence or truth of, especially as a basis for reasoning or arguing.

3. to assume without proof, or as self-evident; take for granted.

4. Mathematics, Logic. to assume as a postulate.


noun 5. something taken as self-evident or assumed without proof as a basis for reasoning.

6. Mathematics, Logic. a proposition that requires no proof, being self-evident, or that is for a specific purpose assumed true, and that is used in the proof of other propositions; axiom.

7. a fundamental principle.

8. a necessary condition; prerequisite.



Do you notice a difference between the two terms?

 

[BrianV]

I just googled:

"class action suit" "protective filter" camera file court

There weren't any class action suits against makers of protective filters. If filters sold to protect a camera lens did not protect camera lenses there would be a class action suit by now.

Any lawyers here want to start a class action suit?

 

[amolitor]

As a PhD in mathematics I actually do know the difference! The way we do science is we form a hypothesis, which involves postulation. Then we perform an experiment. Please look up gedankenexperiment now. In order to devise our experiment, more postulation.

THEN we perform the experiment. The hypothesis is either proven, disproven, or neither!

 

[amolitor]

<an experiment is described>

That's cute, but at this point, it's just another anecdote and, worse, told by someone who I ALREADY think is a poseur who's full of bullspit, and have stated so on previous occasions.

So sorry about your luck with that.

Next time, get some credible witnesses, video-tape, and calibrated instruments to run the testing with.

In the meantime, you REALLY should actually watch the video I posted in this very same thread.

The beautiful thing is that it doesn't actually matter whether I ran the experiment or not it or not since, as noted, it's an anecdote either way and hence unsuitable to you as evidence. Run the experiment yourself, it's the only way to be sure. If you ran it, you'd have your proof, unless the UV filter broke. Which you know perfectly well it would not.

 

[amolitor]

By the way, does anyone actually think that I am advocating the use of filters for lens protection? I'm not. I don't use them, and I don't think they should be so used.

 

[Buckster]

I just googled:

"class action suit" "protective filter" camera file court

There weren't any class action suits against makers of protective filters. If filters sold to protect a camera lens did not protect camera lenses there would be a class action suit by now.

Any lawyers here want to start a class action suit?

Please show where the manufacturer of ANY "protective filter" makes the bold claim that their filter WILL protect a lens from suffering any damage.

A link to the appropriate page on their web site(s) will be fine.

I'll be waiting right here.

 

[terri]

ho hum. Isn't there a large barn you gentlemen can walk behind for this particular pi$$ing contest? :er:

 

[kundalini]

ho hum. Isn't there a large barn you gentlemen can walk behind for this particular pi$$ing contest? :er:

I don't have a large barn, only a small shed in the back of the property. Still, it has gone dark and I don't mind walking ~20 yards beyond the back deck while having a smoke, go behind a bush and consider the to's and fro's of TPF.

 

[Pallycow]

I don't have a large barn, only a small shed in the back

That's what she said.....

 

[Buckster]

<an experiment is described>

That's cute, but at this point, it's just another anecdote and, worse, told by someone who I ALREADY think is a poseur who's full of bullspit, and have stated so on previous occasions.

So sorry about your luck with that.

Next time, get some credible witnesses, video-tape, and calibrated instruments to run the testing with.

In the meantime, you REALLY should actually watch the video I posted in this very same thread.

The beautiful thing is that it doesn't actually matter whether I ran the experiment or not it or not since, as noted, it's an anecdote either way and hence unsuitable to you as evidence.

Actually, it does matter. Due to the fact that you said you ran the experiment, but in actual fact did not, it establishes that you're willing to lie, have done so, and therefore cannot be trusted to be truthful in the things you say going forward.

Run the experiment yourself, it's the only way to be sure. If you ran it, you'd have your proof, unless the UV filter broke. Which you know perfectly well it would not.

Once again, it's YOUR claim, so it's still YOUR burden of proof, not mine.

Good luck with that.