Ilex 8 1/4” f5.6 lens info

[Minarik]

I bought a nuarc 8 1/4” f5.6 process lens, made by ilex. I clearly bought for the 5.6 aperture. It was an impulsive decision. Hopefully not the stupidest one. I was digging online and found only information about the f8 and some 6.3 versions. It is on the way, but I would like to know if this one has the same 80 degree angle of field as the 6.3. If anyone knows any source of information pease share it with me.

I’m planning to use it on 8x10, but I’m dreaming about a big pinhole camera for 16x20 paper negatives. For the 8x10 I will make a guillotine shutter.
Thanks.

 

[GKC]

Will it cover 8x10?
In a dimly lit room point the lens at a brightly lighted scene (like out a window) and see how large of an image you focus on a blank, light colored wall.

 

[Minarik]

Will it cover 8x10?
In a dimly lit room point the lens at a brightly lighted scene (like out a window) and see how large of an image you focus on a blank, light colored wall.

I’m plainly searching for technical information. Can’t wait to test it. Still on its way. Most likely will cover it. I have a 360mm nikon process lens with a 600mm coverage on my Century Master.

 

[Dan Fromm]

I have a 360mm nikon process lens with a 600mm coverage on my Century Master.

Are you sure? I ask because the catalog says that it covers 46 degrees. At infinity that means 305 mm. Might you be reporting coverage at 1:1?

 

[Minarik]

Are you sure? I ask because the catalog says that it covers 46 degrees. At infinity that means 305 mm. Might you be reporting coverage at 1:1?

You are probably right. I hate that.

 

[Barrister]

Take a piece of white poster board and draw an 8x10 box in the center with a sharpie.

Go to a window during the day. Tack a dark cloth around the window with an opening in the middle for the lens - which is open. Turn off the room lights. Have someone hold the lens there with the cloth around it sealing out the light, and use the card to focus the outside image at infinity focus. You'll easily be able to tell if the lens covers an 8x10 negative. Easy and foolproof.

 

[Dan Fromm]

The 8 1/4"/5.6 Wide Field Process Paragon's cataloged coverage is 52 (one source) or 53.1 (another) degrees. 8 1/4", not 12", 8x10's minimum.

The suggestion in post #6 above will measure the circle illuminated, not the circle of good definition.

Oh, yeah, the lens is a 6 elements in 4 groups plasmat type.

 

[Barrister]

Gee whiz! I guess you told me, didn't you?

It's assumed once he sees the image circle that he makes a judgement about coverage for camera movements and where the vignetting and image degradation occurs. Is that okay with you? Should I sit in the corner now?

Gracious, do you need me to send you a note from my mother so I can post on here?

 

[Dan Fromm]

Gracious, do you need me to send you a note from my mother so I can post on here?

Yes, of course. I thought it went without saying.

 

[MattKing]

As a former Barrister, I have a feeling that a battle between the extremely knowledgeable, frequently irascible and always blunt Dan Fromm and the new member Barrister may turn out to be epic.
I'll say welcome to Photrio to Barrister, and tsk to tdk to Dan!

 

[shutterfinger]

Is that okay with you? Should I sit in the corner now?

Gracious, do you need me to send you a note from my mother so I can post on here?

Such a spoiled child. Do you enjoy insulting adults? (rhetorical, no need to reply.)

 

[David Lindquist]

As a former Barrister, I have a feeling that a battle between the extremely knowledgeable, frequently irascible and always blunt Dan Fromm and the new member Barrister may turn out to be epic.
I'll say welcome to Photrio to Barrister, and tsk to tdk to Dan!

I did think Dan's post #9 was appropriately tongue-in-cheek.

David

 

[BrianShaw]

I don’t get it...

 

[choiliefan]

Neither do I...

 

[Minarik]

I applied the lens on a Empire State 8x10. It covers it with movements.