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KevB · Joined: 16 Feb 2012 Posts: 5 Location: Minneapolis

given that this lens is meant for 2 x 3 format is there any particular reason that this couldn't also be used on a Crown Graphic?

Considering the comparable 4 x 5 lens is 203 mm why wouldn't or couldn't this also work?

thanks

Henry · Posted: Fri Feb 17, 2012 8:29 pm Post subject:

According to "Graphic Graflex Photography," 1954 edition (p. 15), the 8" Tele-Optar (202 mm, 2x) is indeed listed for the 2x3 Graphic, as, for that matter, is the 10" Tele-Optar (25 cm, 2.5x). So you should be good to go. Incidentally, the 203 Optar (not a tele) works on my Century; it may be the best lens I own!

KevB · Joined: 16 Feb 2012 Posts: 5 Location: Minneapolis

my bad ... sorry

I should have been specific in my first post and question I have a 4x5 Crown and what I was asking is if the 8" can be made to work on that camera ... again apologies for the confusion

Henry · Posted: Fri Feb 17, 2012 8:51 pm Post subject:

The 8" Tele is NOT listed for 4x5 (above source); the 10" Tele is, however. Don't ask me why; I'm sure that Dan Fromm and others could explain the why/nots.

Dan Fromm · Joined: 14 May 2001 Posts: 2134 Location: New Jersey

The lens can be used on a 4x5 Graphic, i.e., it can be focused to infinity on one. It isn't recommended for use on 4x5 because it won't cover the format.

Telephoto lenses have one large advantage -- back focus usefully shorter than focal length -- that lets them be used comfortably on relatively short cameras. They have one large disadvantage, less coverage than lenses of normal construction.

KevB · Joined: 16 Feb 2012 Posts: 5 Location: Minneapolis

thanks

anyway to figure out what the loss of coverage would be?

45PSS · Posted: Fri Feb 17, 2012 9:54 pm Post subject:

Using the same center point draw a 24mm x 36mm rectangle with a circle that just touches the 4 corners then draw a 6 cm x 4.5cm rectangle with circle, 6cm x 6cm, 6cm x 7cm, 6cm x 9cm, 2 1/4 x 3 1/4 (inch), 3 1/4 x 4 1/4, 4 x 5, 5 x 7, 8 x 10, and 11 x 14.

A lens that is listed for a given format will have an image circle equal to or greater than the circle that encompasses the format it is made for but that image circle will be smaller than the next larger format circle.
Using a smaller format lens on a larger format will result in soft focus in the corners to vignetting to a circular image.

Using a larger format lens on a smaller format will give a lot of movement room.
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The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.

1banjo · Joined: 16 Nov 2008 Posts: 492 Location: kansas

I don't know why they call it a 202mm when 8" = 203.3mm

anyway on page 50 in my 1952 edition
thay say that the 202mm is for upto 3 1/4 x 4 1/4 film size
& the 250mm for 4x5
I don't see anywhere what the Image Circle Giameter is on them

1banjo · Joined: 16 Nov 2008 Posts: 492 Location: kansas

BOBOED

"Image Circle Giameter "Image Circle Diameter !!

Dan Fromm · Joined: 14 May 2001 Posts: 2134 Location: New Jersey

Wollensak ain't sayin'. See http://www.cameraeccentric.com/html/info/wollensak_5.html

KevB · Joined: 16 Feb 2012 Posts: 5 Location: Minneapolis

Thanks all ... Happy to say I found what I had been looking for all along that being a 203 mm ektar

Appreciate your comments and yet another chapter in my Crown Graphic lessons[/url]