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Mark Sawyer
24-Dec-2004, 16:22
Okay, we've all seen `em, some of us got `em: dots on the lenses.

How is a red dot or gold dot or blue dot or yellow dot different from another dot or no dot at all? Is there a standard code where a particular color means a particular thing, or is it different from manufacturer to manufacturer or even lens model to lens model?

And while we're at it, how does a gold-rim dagor differ from just another plain-old-dagor?

Probably common knowledge, but I've never heard...

Jim Rice
24-Dec-2004, 16:29
A red dot on an Artar generally (though I gather not universally) means that it's coated. Gold dots and rims means that they are somehow cooler.

David A. Goldfarb
24-Dec-2004, 16:31
Goerz lenses with dots are generally coated, but ones without dots may or may not be coated. The dots were also used on the latest lenses, so you'll know it's of more recent manufacture than the ones without dots.

Mark Sawyer
24-Dec-2004, 18:30
"Gold dots and rims means that they are somehow cooler."

Oh, that's just great... now I have to take my lenses all apart and have the rims gold-plated just to be cool. Wonder what my gold-rim velostigmat will be worth?

Paul Fitzgerald
24-Dec-2004, 20:16
Hi there,

As per folklore:

red dot Artars were hand picked best of the best;

blue dot Trigors were hand picked best of the best

yellow dot B&L, Kodak, Wollensak were late 40's and single coated

yellow & purple dot B&L, Kodak, Wollensak were early to mid 50's and multi coated, this was dropped by 55? when they were all multi coated

red, green, blue stripes were APO Lanthars, worth keeping

gold rim dagors were the last of American production and none too good A.K.A. nothing special. There were several "Goerz" corp. along the way: Goerz, Zeiss-Ikon, Burke & James, Goerz Am. Opt., a separate American Goerz, Swiss made Goerz, ect. Which one made the gold-rim dagors I forget.

So much for folklore

d.s.
24-Dec-2004, 21:42
I checked all my lenses and looked through them and I saw no dots at all. One did have a very small amount of dust, but no dots. So all in all I guess my lenses are pretty clean. Which I think is cool.



Merry Christmas,
Dee

CP Goerz
24-Dec-2004, 23:38
A red dot on a Goerz Artar means it is a coated version of the original APO Artar. The Red Dots came out in 1955. The red dot signified coating as well as a change in magnification ratio from 1:1 to 10:1.

To confuse matters a little not all APO Artars are uncoated, Goerz would retro coat older lenses for customers.

Blue Dots means Goerz Trigor- a WA process lens that was made for high speed newspaper production. Usually seen in the 14" range but they were made in other focal lengths.

Gold dot on a Goerz Dagor means a late production of the Dagor, the dots came out after the gold 'rims' wich predated the gold anodized aluminum mounts of slightly earlier vintage. The worst version is the Schneider which for some reason gets the highest price though it severly cut down the image circle compared to any other Dagor.

Gold dots/rim Dagors are essentially Dagors with better coating and nicer finish than the earlier ones. I once heard that the later dagors were optimized for F32 as opposed to F45 for the older types but beyond old wives tales have never seen anything in print from the factory about this.

B&L and Wollensak made purple/yellow/blue and one other colour of dot on their lenses too. They used the dots as a colour coding for the different wavelengths of magnesium fluoride in the coatings.

If you have dots anywhere else I would consult a doctor ;-)

CP Goerz

Witold Grabiec
24-Dec-2004, 23:50
If you only see one dot on any of your lenses, it may be OK (it might actually be even better than seeing none at all).

If you see two dots it might be prudent to check the tab.

If you see three or more, you should ask for a lift home.

Jim Rice
25-Dec-2004, 04:54
I have one lens with a dot. It's red, and I seriously love the results from it. So far it's only one dot, but I'm working on it.

sanking
25-Dec-2004, 11:48
"Gold dots/rim Dagors are essentially Dagors with better coating and nicer finish than the earlier ones. I once heard that the later dagors were optimized for F32 as opposed to F45 for the older types but beyond old wives tales have never seen anything in print from the factory about this. "

I converted a 12" Dagor from the 20s or 30s to a gold rim Dagor by removing the black paint on the rim and polishing the brass. A great improvement aesthetically, and the resulting improvement in performance was nothing short of phenomenal!!

Ralph Barker
25-Dec-2004, 14:02
Mark - please note that gold plating the ring is considered rather bourgeois. A solid 14k ring is much preferred. For maximum coolness, the 14k gold lens shade, painted a modest flat black, is also highly recommended. ;-)