Is a center filter needed for 6x12?

[mark]

planning to put my sinar film back to use here soon. It is a 6x12 back but I’ve been reading about 6x17 needing a center filter. I can’t find mention of needing one for 6x12. My assumption is not because it is no larger than 4x5 and my widest lens is a 90mm. But, I thought I would ask.

 

[Ginette]

What is your exact lens? Generally lenses with 100° to 105° and + coverage need CF.
A good article about center filters by Dan Fromm http://www.galerie-photo.com/center_filters_for_large_format_lenses.pdf

 

[Ian Grant]

No you won't need a centre filter with a 90mm lens for 6x12, that's from years of experience

Ian

 

[Dan Fromm]

Ginette, thanks for the plug.

Mark, the rule of thumb Rodenstock and Schneider follow in their CF recommendations is: use a CF for lenses that cover >= 100 degrees, regardless of format. The "regardless of format" part is a little silly. A 90 mm lens sees 70 degrees on 6x12. With the lens centered, the corners will be 1.1 stops down from the center. No real need for a CF in that situation, even with reversal film. Mind you, a CF won't hurt much, except perhaps in the wallet.

You shouldn't need a CF on 6x12 with a lens longer than 65 mm as long is the lens is centered on the gate. But 65 mm is very near the edge, I'd use a CF on 6x12 with a 65.

 

[mark]

Thanks.

 

[mark]

I have a Fujinon SW. if that changes anything.

I just looked at the price of center filters and holy *%>€£. Those are crazy expensive. Won’t be moving to 6x17 any time soon.

 

[Dan Fromm]

A 90 /8 Fujinon SW, claimed image circle 216 mm, should be fine for 6x17. Falloff center to corner -- 2 stops -- will be the same for it as for other 90 mm lenses.

If you're patient and shop steadily eventually you'll find the CF you need at a reasonable price. I have four, the most expensive was for my 35/4.5 Apo Grandagon. It cost around $200 delivered. Getting it took a while.

 

[Ginette]

I have a nice Rodenstock Centerfilter E67/86 that will fit on your Fujinon SW 90 f8. Actually listed with a Schneider Super-Symmar XL 110/5.6 Copal #1. Not a bad choice for someone who like super wide lenses! For the moment I will list both together but someone ask for another lens brand so I read about centerfilters recently and when I saw your question I pointed you the article above.

 

[MTGseattle]

I'm bumping this old thread since I was entertaining the idea of getting something wider for 4x5. 65 or 75mm possibly. I've skimmed @Dan Fromm's article and 5 years on from the last post, I would say that center filter prices have not come down.
The "real" question to me is are there any lenses that border on being useless without a center filter? As an example, the center filter for a Schneider 65mm f8 super angulon seems to start at $300 these days.
Would it be feasible for a 3rd party filter company to make some of these or are they too specifically tied to a given lens for proper function?

 

[Ian Grant]

I have a 65mm f8 Super Angulon, I've not had issues with out a CE filter & B&W film. I rarely use this lens now as I have two 75mm Super Angulons, an f8 on my 6x17 camera and a f5.6 for my 5x4 cameras, With E6 there's a greater need for a CE filter.

On my 6x17 camera there is more noticeable fall off at the edges, I was lucky and found two Hoya CE filters on eBay, listed as second-hand they were from a dealer and new old stock. They were less than $1oo for both, but that was luck, I'd been looking for some years

A member here (in the US) imports from China, that includes filters and the company did list CE filters, however they had quickly stopped making them. The issue is they are actually two pieces of glass and the failure rate is very high, over 50% fail QC, hence the high cost.

I did ask Lee filters if they could make them, I just got a curt no.

Ian

 

[Dan Fromm]

I'm bumping this old thread since I was entertaining the idea of getting something wider for 4x5. 65 or 75mm possibly. I've skimmed @Dan Fromm's article and 5 years on from the last post, I would say that center filter prices have not come down.
The "real" question to me is are there any lenses that border on being useless without a center filter? As an example, the center filter for a Schneider 65mm f8 super angulon seems to start at $300 these days.
Would it be feasible for a 3rd party filter company to make some of these or are they too specifically tied to a given lens for proper function?

AFAIK there are no magic bullets, also no magic lenses for LF. That said, whether your lens would give images that are good enough for you as you intend to use it is really your decision. Try it, and then you'll know.

 

[xkaes]

The four factors that need to be considered with CND filters are the angle of coverage of the lens, the size of the film format being used, how close the image is to the edge of the image circle, and personal preference. If you are using a lens with a wide angle of coverage, but the edges of the film never get close to the edge of the image circle -- even with shifting, etc. -- there's nothing to worry about.

http://www.subclub.org/fujinon/center.htm

 

[MTGseattle]

Thanks.
I won't let the expense of 2nd hand cnd filters keep me from trying a wider lens. I'll just keep an eye on the ones with generous images circles and wait for a deal to emerge. The Fujinon 90mm f8 that I have going for 6x17 seems to be fine without one although I haven't used it a ton.

 

[koraks]

something wider for 4x5. 65 or 75mm possibly

I used 65mm only briefly, 75mm more extensively, although it's been a while. I never had a center filter for either. I can't say I missed it.

 

[xya]

I have a 1:5.6 65mm SuperAngulon that I use on a custom Instax Wide Camera, Instax Wide is only 99mm wide, but it needs a center filter for colour film https://www.instantphoto.eu/other/superwidestax_option.htm. I was lucky to find third party center filters (no indication on them) many years ago for next to nothing and they work.

I also have a Cambo Wide with a 1:5.6 47mm SuperAngulon that I used with peel apart film, 95mm wide. There was some fall-off at the corners, but the image impression corresponded with the super wide image.

When I think about it now, I used the Cambo as well with a Sinar Vario back as 6x12 with B&W film. Seen the specs of the lens that should not have worked, but I remenber results being OK. So I will have to find the camera again in my boxes and run a film through it...