older lenses - eye candy :)

[trundrumbalind]

trund, I was "hmm twice in one day" because I posted the link twice in one day.

Cover has two meanings, "illuminate" and "put acceptable quality image in the corner." Since Schneider and Rodenstock started publishing MTF curves for their lenses its been clear that they usually -- a few Apo-Ronars are exceptions -- define the radius covered as the radius at which the MTF drops below around 5%. Dialyte type Apo Nikkors have about the same coverage as equivalent Apo Ronars so it seems reasonable to believe that Nikon used a similar coverage criterion for them. Also for tessar type apo Nikkors, which have less coverage than the equivalent dialyte type.

When a poster here makes a claim about a lens coverage it is usually impossible to know the coverage criterion used. I believe -- could be mistaken -- that most of us use illumination as the criterion. What's in the corners is often not very important.

I'm sorry, may be going blind, but I don't see a reference to a 480 Apo Nikkor covering 12x20 at infinity in this thread. Until proven otherwise I regard the claim as delusional. At 1:1, yeah, sure.

Misunderstood, sorry.
I was the one you answered to at the apo nikkors thread. Thats what I was refering to.
I dont care about corner to corner razor sharp quality. When I asked about covergae i meant image circle with usable quality. Usable as in " i can distinguish what that is" quality.
Maybe ill have coverage then???

[Dan Fromm]

5% MTF means "its hard to discern what's in the image of a high contrast subject."

But since "usable quality" is pretty subjective, you'd best ask the lens if it can do what you want.

[trundrumbalind]

I did Dan. And if the 480 APO MTF drops to 5% at the corners in 14x17 format, I highly doubt J Conrad would have said it covered 12x20, specially if you consider that 12x20 is more of an infinity focus format than protrait or macro work.
Anyway, as you suggested, I did asked if it can do what I want, it's you who answered out of a specs sheet when I was asking about first hand field experience. In this thread, again, I'm asking if the owner of the MFG has some experience with larger formats or if he knows the projection angle of his lens.
If you have ever used one of these lenses with 14x17 or larger and found that coverage is insufficient, speak up. Otherwise, this is a really pointless argument.

[Dan Fromm]

Sorry, i meant the brown 14"

Interesting. How did we get from here to the 480/9 Apo Nikkor? J Conrad isn't in this thread. You seem to have confused two threads. Not fair.

FWIW, I use my 480 on 2x3 and 6x12. No coverage issues there. If you've used yours and it covers 14 x 17 with enough movements to convince you that it will cover 12x20 at infinity to your satisfaction that's wonderful.

[trundrumbalind]

Oh, this is a pointless argument.

[Jody_S]

Oh, this is a pointless argument.

In 13 posts! This has to be a record. Congrats to everyone involved.