CC Harrison - how to gauge focal length from a picture

[goamules]

Hi, some of you know I'm a collector and scholar of American radial drive portrait lenses. A lot of times a seller doesn't know the focal length of a lens, and you have to make an estimate, or try to contact them before buying and explain how to measure.

But in general, if you know the length of the physical lens you can estimate. In the "mid sizes" say quarter plate to whole plate, the focal length will be approximately what the actual lens length is, with Petzvals. So a lens that stands 8 inches tall (sellers often measure it's height or length only), will be about 7-9" focal length. A lens that stands 11" tall will be about a 9-13" focal length.

Caveats are that it depends on the speed of the lens, and a few other things. But most portrait petzvals are about F4, again in the "middle sizes", and it works for them.

I bring this up because there is a CC Harrison being sold now that is advertised as about 9" long. But the seller says it's focal length is 17.5". That is getting very long, (think of a 16" Vitax) and the lens itself should be much, much larger. The seller also says the lens diameter is 4.5, which would be right for F4. But the lens itself looks small. Something is wrong, this looks like a standard wholeplate size.

[goamules]

OK, I wrote the seller and asked if he actually has measured the focal length. He gave some confusing answers:

"Have I confirmed it myself? No. I haven't. I haven't even mounted this thing on a camera yet. ... This and two other lenses have been in my family for at least three generations. I purchased them from a cousin - who's grandfather had them in his house forever. ...So, I am only able to go from what was written on the card - and it says what I wrote in the auction. Though, I really don't know for sure. ... "

[goamules]

Up to $3,500 now. Somebody is going to be disappointed when they find the focal length isn't what he says.

[Two23]

Up to $3,500 now. Somebody is going to be disappointed when they find the focal length isn't what he says.

There's a BIG difference in value between a lens with FL=9 in. and FL=17 in. If the seller is unsure that's something he damn well better find out. One of the issues I have with sellers is when they say a lens is "8 inches long," do they mean the actual lens or are they including the lens hood? The difference can be a lens that covers 4x5 instead of 5x7.


Kent in SD

[Two23]

Almost $6,000! I would love to find out who bought it and see if it's really 17 inches. For the lens to go that high suggests there's a group of people interested in wet plate and ULF, but really haven't done their homework. To me that's a $1,500-$2000 lens assuming FL=12 in. Just measured my biggest lens, an 1862 Voigtlander, and glass to glass it's 6 inches, lens diameter 3.75, and FL=12 in. Length of the tube without hood is 6.5 in. So, I don't know, maybe FL=16 is in the realm of possibility?


Kent in SD

[goamules]

Yeah, there are a couple ways it could really be 17.5, but unlikely. Like if Harrison made a custom lens, or someone replaced the glass at some point with something else. The knob was replaced for sure. And it was cut for waterhouse slots. Basically it's a hack job lens. I also noted he set it up to be a "private sale" so you cannot see how many different bidders. It could be a shill or two, and it didn't really sell. I just think his answers are suspicious. You own a lot of cameras and sell mostly optics but "haven't had a chance to put it on a camera yet", but in his ad he had time to "Radial Drive adjustment is extremely fluid - that's because it's been remade by a master craftsman. Brand new felt backed lens cap with nipple handle." So what, you do all that, but never figure out the real focal length? You just "copy what was on the card with the lens"?

[Mark Crabtree]

It might be that the buyer is counting on eBay to back them up if the lens isn't what the auction says it is. The title and description seem clear. Even the qualifiers, I think, only mention that there might be minor differences. I'm not disputing anyone's observations, just saying that the buyer might consider the seller to be on the hook for delivering what he described. Or not, we may never know.

I hope somebody here knows about the purchase and can give us an update.

[Kiwi7475]

Very suspicious. And why are half the lens pictures on the site out of focus?

[goamules]

Just to give a comparison, and show what I was saying about the physical length approximating the focal length on early Petzvals:

11 inch early CC Harrison. Stands about 10 inches:



13 inch Willard. Stands about 10.5 inches:

[rdeloe]

Pretty sure that's a small mortar rather than a lens!