Fujinon W 250/6.7 that seems to be a 210

[Per Berntsen]

I bought this lens on ebay, and it arrived today. It is the old version with marking inside filter ring. I also have an NW 250/6.3, and I was surprised to see that the 6.7 lens was smaller and lighter than the 6.3, despite the much bigger coverage.

I was even more surprised when I put the lens on my camera, because it turned out to be much wider than my 6.3 lens. I used a DSLR to roughly establish the focal length of the 6.7, and it seemed to be 210! Measuring the bellows draw at infinity confirmed this - excactly 210 mm.

My first thought was that the lens had been wrongly marked at the factory, but then I found out that the W 210 should have a 58 mm filter thread - this one has 67. The only other thing I can think of is that the rear element is not original. (there are no markings on it)

Weight of the lens is 480 g, rear element is 26 mm long (measured from the lens board), and has a diameter of 60 mm.
If anyone who has this lens could comment, I'd be really grateful. Part of the story is that I'm also looking for a W 210, so I'll make some test shots tomorrow.
Attached photos from the ebay listing.

[Steve Goldstein]

My 250/6.7 takes 67mm filters and a 70mm front cap. The rear cap is 64mm, which differs from your measurement. Overall length is 78.5mm, weight in shutter 617gm. I don't know how much of this is from Fuji literature and how much I've measured myself - the lens is at home, and I'm not, I can check tonight if nobody else chimes in first. I can also screw a 210 rear cell into my 250 and see what happens to the weight.

As you mentioned, the 210 takes a 58mm front filter. The front and rear caps are both 60mm. 505gm according to my self-compiled info spreadsheet (which is also where the numbers on the 250 come from).

[aduncanson]

Measuring bellows draw at infinity is not a good way to determine the focal length of a lens. One needs to measure from the film plane to the rear nodal point of the lens unfortunately the rear nodal point is at some unmarked location inside of the lens. On the other hand, if the image size produced by this lens is distinctly smaller than that of your 250/6.3 then its focal length is shorter.

If you can point your DSLR at the moon and capture a well focused image with both lenses, then the focal length of the unknown lens would be given by.

FL(unknown) = FL(known) * Image size(unknown) / Image size(known)

You should be able to make those measurements with sufficient precision to get a good number. If not, the ultimate solution is to take the focal length as equal to the change in bellows extension as you change the focus from infinity to 1:1. Determine the 1:1 focus point by comparing the image of a ruler to another ruler placed against the ground glass.

[Louis Pacilla]

Hi Per

I just had a look at my 250 f6.7 to check visually against your photos & measurements & I think you may be right. I think the rear cell you have is from a 210 not the 250. The glass in the rear of the 250 is bit more substantial & the body of the cell is larger & the glass is larger than the 210 I put it up against. The 210 fits your measurements.

The 250 rear cell is a solid 30mm from lens board to top of rim & has a girth of 63mm/64 cap.

I think you may need to send her back. Bummer

Hope this helps

Peace
Louis

[John Schneider]

FWIW, I once bought a 300 Fujinon-A that, as I later found out, had the rear element from a 360-A.

[Robert Hughes]

FWIW, I once bought a rock on the Dreaded - turned out it was a ruby the size of my fist! What good is that? Boy did I feel gypped!

[Per Berntsen]

Thanks, everyone. Yes, I think it has to go back, unless the seller can produce the right rear element.

This was a No Returns Accepted listing, but that doesn't apply in a case like this? This was my first purchase from ebay ...

If anyone would like to sell their 250 or 210 (or both), I'd be interested ...

[James E Galvin]

I have 2 of the 250/6.7's. One is fine, but the other has severe spherical aberration, visible on the ground glass without a magnifier. I suspect mismatched cells. I'll check dimensions tonight for both lenses.

[MIke Sherck]

Thanks, everyone. Yes, I think it has to go back, unless the seller can produce the right rear element.

This was a No Returns Accepted listing, but that doesn't apply in a case like this? This was my first purchase from ebay ...

If anyone would like to sell their 250 or 210 (or both), I'd be interested ...

"No returns accepted" shouldn't apply to items where the description was incorrect. They can't say "no returns accepted", advertise a gold rim dagor and send you an Ektar in a broken Supermatic!

I hope.

Mike

[jb7]

If you can make a measured 1:1 image, then divide the subject to image distance by 4, that's the focal length-

I've got a 210 5.6, and the rear cell looks similar, it takes a 58mm filter too-
though it has an inner thread, your one doesn't look threaded...