4x5 wide lens questions.

[buggz]

Hello,
I recently got a roll film back for my Sinar F2.
I want to try the 6x12 option mask.
Will this necessitate a wide angle lens?
I guess not, as I am currently using a cemented pair meniscus lens from Jim Galli in a Polaroid shutter now.
Have to try my Sinaron S 180mm.
I see some Fuji 90mm in Copal shutters on the bay that are tempting me...
Are those considered wide for 4x5?
I also see Tomicon 75mm lenses, but, aren't these macro type lenses?

[Jac@stafford.net]

A lens that will cover 4x5" will cover nominal 6x12cm.

An excellent chart here: http://www.largeformatphotography.info/lenseslist.html

[Dan Fromm]

I also see Tomicon 75mm lenses, but, aren't these macro type lenses?

If you mean Tominon, these wee beasties aren't wide angle lenses and won't come close to covering 6x12, let alone 4x5. If you want a 75 that covers 6x12 or 4x5, you'll have to spend real money. Look at LF lenses offered on classic.keh.com to get an idea of prices.

If you can live with an 80 mm lens, the 80/6.3 Wide Field Ektar will just cover 6x12, won't cover 4x5. Not that common, though.

[buggz]

Great information!
I love this place.
Yes, I am STILL a "newbie", probably will be forever.
Guess that is why I like photography, ALWAYS learning, and experimenting.

[Jmarmck]

It is all about the size of the image circle of each lens. The image circle needs to be larger that the diagonal of the format you are shooting. For instance the diagonal distance of a full 4x5 sheet, corner to corner, 160 mm. Do the math for a 6x12 diameter. The focal length really has little to do with it. Rodenstock made 75s in two apertures, f4.5 and f6.8. The largest image circle of the f4.5 is 13 mm larger than the 6.8. See the link for the chart that Jac posted.
Bottom line is that you need to know the image circle and judge whether or not it covers your format. This applies to any focal length.

[Jac@stafford.net]

Buggz, consider measuring the actual size of your 6x12 frame before calculating circle of coverage. It is smaller than the given size.

[Dan Fromm]

Buggz, consider measuring the actual size of your 6x12 frame before calculating circle of coverage. It is smaller than the given size.

Most 6x12 roll holders have gates 56 x 112 mm, diagonal 125 mm. The big exception is Linhof's, 56 x 120, diagonal 132 mm.

[Fotoguy20d]

If you want a 75 that covers 6x12 or 4x5, you'll have to spend real money.

You can sometimes find a Goerz Rectagon fairly cheap. Barely covers 4x5 though.

[hmf]

As Jac said, any of your lenses that cover 4X5 will also cover 6X12. The question, I think, should be what kind of perspective are you looking to achieve in your 6x12 images? A wide angle perspective will emphasize the foreground, push the background away and give relatively deeper depth of field. If you use a more "normal" lens for the format, you'll get a "normal" perspective 4X5 image with the top and bottom cut off.