Konica GRII series coverage

[Dan Fromm]

Dan,

Staggering conclusion in this age of information strewn throughout the Internet, but one that I cannot dispute from my efforts.

Thanks for the reply,

Len

Len, that's information on the internet. When I search I'm often buried in, um, nonsense that has little to do with what I'm looking for. Unfortunately he web houses some knowledge, far from all. And some, perhaps much, of what's on it just ain't so.

Not to denigrate the photo presented in post #36 below, but it doesn't really answer the question of how large a circle the 260 GR II covers. That it covers 5x14 means that it covers 72 degrees. Useful, but not a lot. And the image, although pleasing, has softness built in.

[erie patsellis]

Mamiya RB have similiar rumors

Actually, waaaay back when, circa 2005 or 6, I measured the coverage of some of the RB lenses, the 90 and up cover 4x5 The 50 and 65 miss by a bit. However they do illuminate sufficiently the Betterlight back area. This was around the same time I built my Mamiya/Toyo hybrid.

[Kiwi7475]

OK, resurrecting an old thread, but in my search for info on the Konica Hexanon GR II lenses am unable to find any real specs on them.

I recently acquired a 150, 260, and a 300, and when mounted on the 8x20 Korona Panoramic View, the two longer ones "lit" up the corners and was able to see an image, but I did not expose any film (8x20 sheet is expensive!).

Has anyone seen factory specifications for these lenses, or comprehensive tests? Or is everything opinions?

You could expose just using one 8x10 sheet cut in half (2 8x5s effectively) and placing them at either ends of the holder to confirm the corner sharpness and coverage. Or just use one 8x10 sheet to the “bottom” part of the holder, covering from center to one edge. That is a much cheaper way to see if it meets your standards.

[jprofita]

I chose the image above because it clearly shows the falloff towards the edges. I would assume this would be more pronounced with 7x17. I personally liked this effect along with the grittiness from shooting old paper to get the feel of the dry lake. The lens is very sharp, softness results from using paper rather than film or making it too small for posting.

[Tin Can]

I really have no idea what this means in context to this thread.

Specs for RB also show big 'coverage'

Look up the Data

Now do you Grok?

[Len Middleton]

Len, that's information on the internet. When I search I'm often buried in, um, nonsense that has little to do with what I'm looking for. Unfortunately he web houses some knowledge, far from all. And some, perhaps much, of what's on it just ain't so.

Dan,

Indeed that is often the case.

Having worked in industrial environments, I typically expected to have available some specification provided by the manufacturer indicating functionality and performance when making a significant purchase. I was sort of hoping that since the 2005 start to this thread, maybe someone has a copy of those specifications.

What was the typical price range of a graphic / reproduction lens when they were new? Certainly in dropping that much coin, would like some documented guarantee on its performance relative to requirements (e.g. 1:1 reproduction).

It does remain surprising to me,

Len

PS And yes in using the Internet searching for specific information, to use the mining analogy, one often has to move a lot of overburden to get that first diamond

[Dan Fromm]

Specs for RB also show big 'coverage'

Look up the Data

Now do you Grok?

Sir, you're not critical enough.

See http://www.mamiyaleaf.com/legacy_RZ80.asp

Click on “Lenses and Accessories.” “Area covered” in the documentation is the size of the subject at the lens’ close focusing distance. Counting on the lenses to cover much more than 6x7 doesn’t seem safe.

[Tin Can]

Bad link

Thank you

I generally don't use 'safe' for image making

as this is art'

not bomb sight

Sir, you're not critical enough.

See http://www.mamiyaleaf.com/legacy_RZ80.asp

Click on “Lenses and Accessories.” “Area covered” in the documentation is the size of the subject at the lens’ close focusing distance. Counting on the lenses to cover much more than 6x7 doesn’t seem safe.

[Lachlan 717]

Specs for RB also show big 'coverage'

Look up the Data

Now do you Grok?

Couple of things - why would I look up specs on a medium format system in the context of large and ultra large format? Second, what on earth is “grok”?

[Mark Sawyer]

You could expose just using one 8x10 sheet cut in half (2 8x5s effectively) and placing them at either ends of the holder to confirm the corner sharpness and coverage. Or just use one 8x10 sheet to the “bottom” part of the holder, covering from center to one edge. That is a much cheaper way to see if it meets your standards.

A full paper negative might be the way to go.