[monochrome]

From what you are saying, it must never be touched with anything. How to remove it then? Breath is worst idea imo, you are transferring just who knows what kind of materials including acids and etc that way

I had a fraternity brother who had Thermonuclear Death Breath1, but Acid Breath2? Yikes!!!

1 Godzilla Breath
2 Should be a Band name.

[Lev]

I had a fraternity brother who had Thermonuclear Death Breath1, but Acid Breath2? Yikes!!!

1 Godzilla Breath
2 Should be a Band name.

There was nothing but a clean water if you'd like to know, but thanks anyway. Thing is not in what I have applied really, thing is how I did cleaning process.

[stevebrot]

Should be a Band name.

Breath that gouges (BTG)


Steve

[monochrome]

Breath that gouges (BTG)


Steve

”Jagged Little Pill” - Alanis Morissette ()

[35mmfilmfan]

I always carry, in a sealed plastic bag, a well-washed cotton handkerchief for all such issues. Breathe gently on the smear, then wipe it with the wadded cotton. Once home, see if further action is required. Unless grit or other contaminant is present, the coating on modern lenses should be tough enough to withstand gentle cleaning with no ill effects. Once home, handkerchief is swapped for another of the same ilk, and goes for a boil wash.

[Lev]

I made a call to precisioncamera, they want $350 just to look at it :/

Guys, how much it will go up?

[BigMackCam]

I made a call to precisioncamera, they want $350 just to look at it :/

Guys, how much it will go up?

Lev, are you able to take a photo of the rear element to show us? And can you tell us what items you finally used to clean it?

It's extremely unlikely you've scratched the rear element... It's possible, of course, but really very unlikely, even if you weren't quite so careful as some of us recommended. Modern lens optics are generally a lot more robust than you think. It's far more likely that you've merely smeared the element with your finger grease, or managed to contaminate it with something else (sticky residue, perhaps)... in which case, it's still perfectly possible to clean.

Even if you've scratched it slightly, there's a good chance that it won't affect performance - and if it does, it may be so slight that you don't need to worry about it.

Anyway, I'm getting ahead of myself. Before you spend good money on having a service facility look at your lens, try to photograph that rear element and let us take a look for you

[Lev]

Lev, are you able to take a photo of the rear element to show us? And can you tell us what items you finally used to clean it?

It's extremely unlikely you've scratched the rear element... It's possible, of course, but really very unlikely, even if you weren't quite so careful as some of us recommended. Modern lens optics are generally a lot more robust than you think. It's far more likely that you've merely smeared the element with your finger grease, or managed to contaminate it with something else (sticky residue, perhaps)... in which case, it's still perfectly possible to clean.

Even if you've scratched it slightly, there's a good chance that it won't affect performance - and if it does, it may be so slight that you don't need to worry about it.

Anyway, I'm getting ahead of myself. Before you spend good money on having a service facility look at your lens, try to photograph that rear element and let us take a look for you

thanks!

Well, I bought 99.9% IPA, cotton qtips, distilled water and gloves. Prior to cleaning, just in case, contacted Pentax by email asking what to do to clean the rear element. Got email saying remove dust then use water.

I decided to listen to myself and Pentax rep to not use IPA as a cleaning solution and try to remove the fingerprint smear using just a qtip and water.

This fingerprint was there already a week. As nothing is here, not a single professional service shop to help you in such cases, I was just much worried not to let it sit there and damage the coatings. Same goes to front element, there are couple of fingerprints but first I wanted to fix rear as it's harder.

So I have started. I can't tell you how many times I used my Giosso blower to remove dust and debries, by holding the lens upside down, with some different angles. I didn't use brush, as I thought maybe it's too much contact. Started cleaning with wet qtip from center with circular motions very gently, then dry one. Couple of times this way and I have noticed it. Also noticed a tiny white speck on surface, maybe it was just a lint coming from qtip or I missed a dust particle, I immediately removed it by blower. I can't be sure that it is indeed a scratch as when I hold the lens against light it looks like scratch but when it passes light it looks like another line of smear.

Now I'm trying to take a photo of it but seems like my DFA100 cant pick it up because I can see it when the bulb light hits around it but when I try to make photo there is not enough details because of that reflecting light. I made a couple of other photos of surface at different angles but there are so many smudges it makes no sense, this tiny thing is not visible at all. I guess now I'm in real trouble because somehow I need it to get perfectly clean to go farther inspecting it. One thing is certain that I have just distributed that smudges around instead of cleaning it. The water simply not able to remove it, and the Pentax suggestion to use just water is useless along with my positive opinions regarding washing capabilities of it against an oily things. I'm writing this with my cell phone, I'll post these pictures later but I think it makes no sense as there are just hell amount of smudges.

[Benz3ne]

thanks!

Well, I bought 99.9% IPA, cotton qtips, distilled water and gloves. Prior to cleaning, just in case, contacted Pentax by email asking what to do to clean the rear element. Got email saying remove dust then use water.

I decided to listen to myself and Pentax rep to not use IPA as a cleaning solution and try to remove the fingerprint smear using just a qtip and water.

This fingerprint was there already a week. As nothing is here, not a single professional service shop to help you in such cases, I was just much worried not to let it sit there and damage the coatings. Same goes to front element, there are couple of fingerprints but first I wanted to fix rear as it's harder.

So I have started. I can't tell you how many times I used my Giosso blower to remove dust and debries, by holding the lens upside down, with some different angles. I didn't use brush, as I thought maybe it's too much contact. Started cleaning with wet qtip from center with circular motions very gently, then dry one. Couple of times this way and I have noticed it. Also noticed a tiny white speck on surface, maybe it was just a lint coming from qtip or I missed a dust particle, I immediately removed it by blower. I can't be sure that it is indeed a scratch as when I hold the lens against light it looks like scratch but when it passes light it looks like another line of smear.

Now I'm trying to take a photo of it but seems like my DFA100 cant pick it up because I can see it when the bulb light hits around it but when I try to make photo there is not enough details because of that reflecting light. I made a couple of other photos of surface at different angles but there are so many smudges it makes no sense, this tiny thing is not visible at all. I guess now I'm in real trouble because somehow I need it to get perfectly clean to go farther inspecting it. One thing is certain that I have just distributed that smudges around instead of cleaning it. The water simply not able to remove it, and the Pentax suggestion to use just water is useless along with my positive opinions regarding washing capabilities of it against an oily things. I'm writing this with my cell phone, I'll post these pictures later but I think it makes no sense as there are just hell amount of smudges.

The one thing to note is that, against the Pentax Rep's advice (as you said yourself, is useless in this instance), there is a lot of anecdotal evidence for IPA working at varying concentrations. Perhaps, if you've some small cups available, mix a 20:80, 40:60, 50:50, 70:30, 80:20 mixture of IPA:distilled water and try using them on the rear element, from lower strength to higher strength. I've typically opted for 70:30 and that has worked flawlessly for me (i.e. 70% IPA, 30% water).

If it's a scratch, you're not going to do any harm by further cleaning the scratch. If it's a smudge (as it sounds like, given your description in different angles of light) you might well save yourself the $350+. It sounds like you've done everything as advised (blower, damp Qtip, dry Qtip, blower wherever necessary in between etc.) so it sounds like the fundamental flaw is using only distilled water.

Don't panic too much, as others have stipulated it's quite difficult to scratch the rear element so unless you were particularly heavy-handed or your Qtips are made from sand, then you probably have nothing to worry about!

Let us all know how you get on with the above - water doesn't mix with oils, IPA does (generalisation)!

[Lev]

The one thing to note is that, against the Pentax Rep's advice (as you said yourself, is useless in this instance), there is a lot of anecdotal evidence for IPA working at varying concentrations. Perhaps, if you've some small cups available, mix a 20:80, 40:60, 50:50, 70:30, 80:20 mixture of IPA:distilled water and try using them on the rear element, from lower strength to higher strength. I've typically opted for 70:30 and that has worked flawlessly for me (i.e. 70% IPA, 30% water).

If it's a scratch, you're not going to do any harm by further cleaning the scratch. If it's a smudge (as it sounds like, given your description in different angles of light) you might well save yourself the $350+. It sounds like you've done everything as advised (blower, damp Qtip, dry Qtip, blower wherever necessary in between etc.) so it sounds like the fundamental flaw is using only distilled water.

Don't panic too much, as others have stipulated it's quite difficult to scratch the rear element so unless you were particularly heavy-handed or your Qtips are made from sand, then you probably have nothing to worry about!

Let us all know how you get on with the above - water doesn't mix with oils, IPA does (generalisation)!

thanks a lot for help!

yes, absolutely sure that just water is out of options. Now question is whether to use qtips again. I don't think it causes scratches because otherwise I'd have them all over the whole surface I've touched. It is obvious that it will require less moves on surface using other materials like microfiber cloth or lens tissue but now I'd have to "experiment" with new things which never been used on this lens.

[Benz3ne]

thanks a lot for help!

yes, absolutely sure that just water is out of options. Now question is whether to use qtips again. I don't think it causes scratches because otherwise I'd have them all over the whole surface I've touched. It is obvious that it will require less moves on surface using other materials like microfiber cloth or lens tissue but now I'd have to "experiment" with new things which never been used on this lens.

Very welcome - I would say QTips are fine. Again, anecdotally, plenty of people (myself included) have cleaned multiple lenses with them!

[rogerstg]

Since you are very concerned, perhaps you should consider buying products created for this purpose; Eclipse and PEC pads.

Eclipse is simply methanol, the same ingredient as found in yellow Heet (gas-line antifreeze) but comes in an easy to use dispenser.

[Lev]

Since you are very concerned, perhaps you should consider buying products created for this purpose; Eclipse and PEC pads.

Eclipse is simply methanol, the same ingredient as found in yellow Heet (gas-line antifreeze) but comes in an easy to use dispenser.

I bought some products this morning including ROR, Zeiss Lens Cleaner fluid and a cloth and some lens tissues... but I'm worried to leave the lens in this condition for a long time because these products will arrive in a week or so.

[Benz3ne]

Since you are very concerned, perhaps you should consider buying products created for this purpose; Eclipse and PEC pads.

Eclipse is simply methanol, the same ingredient as found in yellow Heet (gas-line antifreeze) but comes in an easy to use dispenser.

I'd just like to chime in to say please exercise caution when using methanol. It's exceptionally nasty stuff with widely-reported toxic effects even at relatively low concentrations in humans.

Good advice with regards to items that have worked for you.

To the OP: as you want something immediate to try, you should try the IPA:water mixture, without wanting to repeat myself (and others).

[rogerstg]

I bought some products this morning including ROR, Zeiss Lens Cleaner fluid and a cloth and some lens tissues.

FWIW, the Zeiss product is appx 5% isopropyl, 95% water.