In my on-going saga re my cleaned-with-Brillo-pads '47 Ektar lens...after shooting some test shots, the focus is soft with some flaring on super-whites. Dredging up all of the magnification at my disposal, it appears that most of the scratches are in the coating of the front element, as well as some general deterioration of the coating. My question is: does anyone know how to chemically remove the coating? I believe the lens may be useable if I do so. Thanks. Fred.

http://www.deardorffcameras.0catch.com/index.html

somewhere on theis site is a contact for ken Hough. Tell him is was "one ought" steel used and you've tested the lens and found it lacking.

Then ask him what the options are, removal, recoating, can a laymen successfully remove it? etc.

Then ask how much.

The worst case scenario is that it's cost more to remove than to buy a 'good' one. In which case I''d look into Edmund Scientific and see what they have for a lens grinding kit, for the correct steel wool or compound.

Thanks again, Les. I'd rather eat a worm than discard this fine old vintage stuff. I'll go to whatever lengths are necessary to reclaim this good old lens. I've heard of "jeweler's rouge" as a super-fine polishing agent, but don't know if it would do the trick. I'll try your suggestions first.
Fred.

Quote:

On 2002-09-21 16:52, clnfrd wrote: Thanks again, Les. I'd rather eat a worm than discard this fine old vintage stuff. I'll go to whatever lengths are necessary to reclaim this good old lens. I've heard of "jeweler's rouge" as a super-fine polishing agent, but don't know if it would do the trick. I'll try your suggestions first. Fred.

Um, Fred, John VanStelten of Focal Point Optics will probably recoat your lens' front element, but getting another one will cost a lot less. He estimated $175 to do one for me. Not a Kodak, but still ... Yes, I know, its your money and your madness.

Cheers,

Dan

Well, Dan, my madness only goes so far. I'm really into do-it-yourself. That's half the satisfaction of it all. I'm still hoping to come up with a do-it-yourself means of chemically removing the coating to see how the glass really is. The Kodak shutter works perfectly after cleaning...and, since I just acquired another Raptar for my 2X3 cameras, I can toy with the Ektar a bit. Thanks. Fred.

As long as your 'madness only goes so far' and you're a do-it-yourself-er, I may as well join in
Somewhere around here, I left a message about an old lens I had, and wanted to get the coating removed. Don't rewmember any replies as to how to, so I went at it. It was a worthless lens anyway... I tried everything from chemicals to toothpaste. Wound up using a circle of 6 ounce leather and jeweler's rouge. Tried at first by hand. It worked, but I didn't have that much energy. So I switched to a Dremel. Worked great. I can't see any fog or scratching from the polishing. I've done this with rough cast brass parts and gotten a shine so fine that a touch of a finger or wipe of a facial tissue would scratch the resulting surface. To get the finest surface, use the leather/rouge wet. There are a lot of different 'rouge's on the market and they're not all equal... Use the flesh side of the leather (not the smooth side).

So, I won't tell you or anyone else to do that. I won't even recommend it... But I did it and it worked fine. With the dremel, it only took maybe 15 minutes to remove all the coating (don't really remember).Unfortunately for that lens, it didn't make any difference because most of the scratches were in the glass itself...

Good luck, and I'm waiting to hear what you finally decide on and how it works. I've got a couple of lenes that could use a coating removal someday...

What the heck, Rich...I'll get me some Rouge and leather and give it a go. I have some compound I used to remove scratches from a windshield I may resort to if the scratches are deeper than the coating. And Les...I surfed Edmund Scientific to no avail....and couldn't find Ken Hough in a site search. Thanks to all...and to all a goodnight. :grin:. Fred.

Here's Ken's site.

http://deardorffcameras.0catch.com/

Thanks, Alecj. I already visited this site, which Les had suggested, not knowing it was Hough's site. Will do it again. Fred. P.S. I must be brain-dead at times. In re-visiting it, it plainly states it is hosted by Ken Hough's Photographic repair service. Thanks again.

<font size=-1>[ This Message was edited by: clnfrd on 2002-09-23 04:43 ]</font>

k4sb@niia.net Ken's email

I dug out the dry white powdery polishing compound I received from an auto glass repair center....moistened a piece of cloth cut from an old sweatshirt and started polishing by hand. I have developed a new respect for the hardness of the lens coating and glass. After a couple of hours of polishing and resting, I have been successful at removing most of the scratches and the coating appears to still be mostly intact. I can't believe this, but the lens now looks good enough to use. As hard as it is, it's hard to believe it got so scratched to begin with. I expected this approach to scuff and render the lens useless...but not so. It's bright and clean with only a little of the scratches remaining on the outer edge where it's difficult to apply adequate pressure. If anyone is interested, I'll find out what the name of this polishing compound is. I was originally told it was one step more aggressive than jeweler's rouge. I know I used it to polish out scratches from a faulty wiper on a Jeep windshield with good success. The old '47 Ektar lives to fight another day!:D:D:D Fred.
What happened to the smilies. Should have three green smiley faces. After testing, I think I should have spaced between each colon-D...:grin:






<font size=-1>[ This Message was edited by: clnfrd on 2002-09-26 17:04 ]</font>

I, for one, would like to know what polishing compond it is and where I can get some.
Charles

The product, according to Paducah Mobile Glass, is Pumice, mfd by C.R. Laurence. They sell only to dealers. Info at crlaurence.com. The Pumice comes in two grades...2F (coarse) and 4F (fine). Their web site will give info on local dealers. Believe it or not, the coarse, 2F, is what I used with success on the Ektar lens. The dealer said they also have used Bon Ami. I would think that is too coarse. Chances are any local dealer would let you have a bit as mine did, because it comes in a 4-lb bucket. Fred.

2F 4F and Rottenstone (the finest) are sold in 'better" woodworking supply stores in 1 lb packages. I believe it's marketed by Behlen

The Bon Ami may not be as far-fetched as it sounds. Years ago, Kodak recommended "only cake Bon Ami" for polishing ferrotyping tins (remember them?). Accordingly, I purchased a bar of the stuff. It's been sitting, in its original wrapper, under the sink in my darkroom for going on 30 years. Don't know if it's even available anymore, but the first place I'd look would be your well-stocked country hardware store.