dubious coverage claim in for sale listing

[Dan Fromm]

Since I can't append a comment to the listing I tried to archive it before posting this. The result is at http://web.archive.org/web/20161012115431/http://www.largeformatphotography.info/forum/showthread.php?133998-For-Sale-75mm-f-4-5-Tominon-Compure-100 Short answer, posts on this site can't be archived because archive.org can't log in to it.

This link www.largeformatphotography.info/forum/showthread.php?133998-For-Sale-75mm-f-4-5-Tominon-Compure-100 works.

I'm posting this because I don't trust the seller to pay attention to a PM.

The seller claims that a 75/4.5 MP-4 Tominon covers 4x5 at infinity. Polaroid, who should know, says that it covers 4x5 at magnifications greater than 2:1. 2:1 is a little closer than infinity.

The seller also claims that the lens is in a "compure press shutter." Spelling error aside, this is barely possible, but if so the lens is not an MP-4 lens. MP-4 lenses are in barrel, screw into the front of a #1. All Polaroid gelcam lenses are in shutter, usually Polaroid Copal #1 Press.

[BrianShaw]

What is the definition of "unfinity"????????

[Willie]

That is infinity plus 25 yards. Chuck Norris has been there twice.

[Drew Wiley]

Eval Knieval almost made it that far.

[Jac@stafford.net]

What is the definition of "unfinity"????????

It is the term describing the illusion of making landscape photos (@infinity, aka offfing) at high shutter speeds.
:)

[Leszek Vogt]

Ha, I saw that lens on my local CL....and I broke records sprinting away from it. Hmmm, at a v. low price ($10) I should have given a chance.:D

Les

[RichSBV]

A whole bunch of worthwhile comments???

I would have thought that everyone here would know that the lens won't cover 4x5 at infinity and definitely not at unfinity.

However, and could be entirely wrong about this, I thought many of the MP4 lenses did come in shutter? I am very sure that the few I have are, but haven't seen them in a few years. As I remember, similar to a press shutter; no cocking.

Who knows and apparently there's little seriousness in this thread anyway ;-)

[stawastawa]

What is the definition of "unfinity"????????


That is infinity plus 25 yards. Chuck Norris has been there twice.


Eval Knieval almost made it that far.


It is the term describing the illusion of making landscape photos (@infinity, aka offfing) at high shutter speeds.
:)
:)

^^^
well I guess this kind of commentary is why we are no longer allowed to comment on FS threads. :)
- though I find it amusing to read too - even if they arn't the most informative posts.

Thank you dan for posing the question and setting the knowledge base straight on this issues (unless more evidence surfaces, or Rich finds his collection of Mp4 lenses in shutter somewhere).

[Dan Fromm]

Rich, you may be thinking of lenses for the MP-3. Most of them -- the 35/4 Eurygon is an exception -- are in shutter, usually a Prontor Press #1. The move to front-mounted lenses in barrel with the MP-4 reduced users' costs.

[BrianShaw]

What is the definition of "unfinity"????????

FYI: I was recently informed that this is modern slang for "the smallest non-zero number possible". Not sure if that was intentional or a typo in the ad Dan was commenting on. Also not sure what this has to do with anything... but is interesting (to me, at least).

[Leszek Vogt]

OK, as Dan mentioned....

http://seattle.craigslist.org/kit/pho/5783187146.html

This lens has been for sale for several years now. The v. first give away was, that NO coverage was given. The guy upped the price since the last time I saw it. :>)

Les

[mdarnton]

I have the 135mm on one of my 4x5s. Since I shoot portraits where everything is central, I can't comment on marginal sharpness, but it throws a larger image than a 135 Wolly. I think $20 is a steal.

[Dan Fromm]

Michael, I've shot three of the wretched things on 2x3. They all failed acceptance testing on central sharpness closeup and a distance.

[Jac@stafford.net]

Michael, I've shot three of the wretched things on 2x3. They all failed acceptance testing on central sharpness closeup and a distance.

Perhaps we should have a category for Worthless Lenses.

[Two23]

To unfinity..........and beyond!



Kent in SD

[Peter Gomena]

Unfinity = infinity minus 1.

[Jim Galli]

Perhaps we should have a category for Worthless Lenses.

I think Dan has described the "category" for us very well. Wretched.

It is a Tessar and has the usual 60 degrees of cone of light. So where does 60 degrees cover the diagonal of a 4X5 sheet? Somewhere around 120mm. So when your bellows is at 120mm with a 75mm lens you've moved in pretty darn close. Not 1:1 but getting in the 'hood'. Also, BEWARE, as many of these are on Polaroid Copal shutters and DO NOT have an aperture.

As Dan says, some basic knowledge can go a long way when you're entertaining yourself with a bag of Cheetoh's and reading the latest lies on ebay and craigslist. It's up to YOU to know what you're buying. No one else.

How did I learn what I know? By gullibly buying all sorts of worthless trash and taking my lumps.

[Jac@stafford.net]

So, why not have a hammer down on the crap? Is it not worth a category to at least point to?

[Willie]

I think Dan has described the "category" for us very well. Wretched.

It is a Tessar and has the usual 60 degrees of cone of light. So where does 60 degrees cover the diagonal of a 4X5 sheet? Somewhere around 120mm. So when your bellows is at 120mm with a 75mm lens you've moved in pretty darn close. Not 1:1 but getting in the 'hood'. Also, BEWARE, as many of these are on Polaroid Copal shutters and DO NOT have an aperture.

As Dan says, some basic knowledge can go a long way when you're entertaining yourself with a bag of Cheetoh's and reading the latest lies on ebay and craigslist. It's up to YOU to know what you're buying. No one else.

How did I learn what I know? By gullibly buying all sorts of worthless trash and taking my lumps.

Has to be the Jalapeno Cheetos. None of the bland stuff.

[Dan Fromm]

Jim, Jac, I dunno. There are people who like what lenses I, possibly both of you too, see as unusable (or not worth buying when better lenses are available for around the same price) do. There are people who enjoy looking for buried treasure and aren't bothered by finding pyrite instead of gold. And there are people -- I'm sometimes one -- who think that sharpness isn't always the only thing or even very important. And there are huge differences of opinion about what's usable. People's needs and the standards to which they work vary.

I don't think its safe to tell anyone not to use a lens. I mean, Polaroid sold many MP-4s and many 135/4.5 Tominons for them. The lenses did what the users needed them to do well enough. That I dump on them doesn't mean they didn't meet Polaroid's or paying customers' needs. The ones I tried didn't meet mine as well as other lenses did.

Jim, MP-4 Tominons are all in barrels with diaphragms. They're made to screw into the front of a Copal Press #1 that was made for the MP-4 system and that has no diaphragm. Having one shutter for as many as six lenses saves the customer money. And, when the lenses are used as recommended they all cover 4x5 with no mechanical vignetting by the shutter. When they're used as recommended.

[Jody_S]

Perhaps we should have a category for Worthless Lenses.

A shelf. Or a shoebox.

[Mark Sawyer]

The seller claims that a 75/4.5 MP-4 Tominon covers 4x5 at infinity. Polaroid, who should know, says that it covers 4x5 at magnifications greater than 2:1. 2:1 is a little closer than infinity...

Really, I'm surprised you all don't know these terms...

"Infinity" in this case refers to the focal length of the lens when focused on an object as far away as possible. "Unfinity" is obviously the opposite, the focal length when the object is as close as possible, i.e.: in direct contact with the front of the lens. And in the seller's defense, the Tominon probably covers 4x5 at that distance...