Advice on filters for large (105 mm) ring size

[Al Miller]

Hi.

I've recently been putting together an 8x10 system, and have purchased a Caltar II-N 360mm lens, which has a filter ring diameter of 105mm. I'm looking for advice on filter systems for B&W work. For my 4x5 and 35mm systems I've always used screw-on ring filters, but the 105mm filters are hard to find and very expensive. I've been watching eBay, haven't seen anything used come up there....

Should I bite the bullet and special order the ring filters, or put together a 4x4 resin system? One downside with the resin system is that it won't fully cover the 105mm lens opening, but I rarely shoot with a fully open aperture, so I doubt that would be too much of a problem. This being a hobby, I'd like to keep the budget as reasonable as I can without sacrificing quality and usability (yeah, dream on )....

Thanks!

Al

[Gem Singer]

You are absolutely correct. 105mm screw-in filters are relatively expensive. However, you really don't need a large variety of filters for B&W photography. Midwest Photo Exchange (www.mpex.com) and K.E.H. (www.keh.com) list several 105 filters, new and used, on their websites. Resin filters in 4 inch squares are going to be very difficult to keep clean and scratch free in the field.

[Eric Woodbury]

I use 4" gels in cardboard holders and a little holder that Lee filter makes that is held on with a rubber band. Since most pictures are taken withOUT a filter, I haven't had to change my gels in the 7 years since I switched over from glass (before I had a large diameter lens). Gels work fine.

[Jim Rice]

Eric, I'd be interrested in hearing more about the Lee holder. Their web site is a bit minimalist.

[tim atherton]

I think the new super X pro sized ( or whatever it's called) Cokin holder might cover 105mm - not sure if it works out cheaper?

(having just got an old "budget" 165mm Super Angulon that takes 105mm filters I've been looking around as well)

[Michael Kadillak]

I just contacted Lee Filter in California (I believe) about a similar situation with acquiring B&W filters for a 35" Red Dot Artar and based upon what the sales rep told me, I feel that the answer to your question and mine is to have Lee make you a set of custom polyester filters to the precise size and shape (square, circular or rectangular) that you need. Then it will only require you to find or build a front mounted device to hold them in place when you make a photograph.

Their resin filters in the larger sizes (4" x 4" and larger) are over $100 each and while the rep could not tell me the exact price for the polyester filters. he did indicate that they were considerably less expensive alternative. Unless someone more knowledgable than I on this subject would advise against using polyester filters, that is how I would go.

By all means, save your money to but as much LF film as possible.

Back to the darkroom.

Cheers!

[Eric Woodbury]

Whoops! So sorry, I gave you bad info on the Lee filter holder, called Gel Snap. This is a good unit, but only works up to 82mm. I have the 72mm SA XL and I think it needs a 96 or 100 mm filter. For this I use another trick that might work fine for you with gels.

I trace the outside diameter of the lens onto a piece of foam core, about 5" square. I cut the hole as marked so that the foam core just slides on 'nice'. Then I put a couple of corners, like photo corners on the front (either side). These corners are 4" apart so that I can slip a 4" gel into the corners for when I take the picture. You could also use a paper clip or something to hold the filter on there. Four inches is probably big enough gel or polyester. You don't shoot through the whole thing (i.e. the open diameter of the lens is less than 4"). Hope this makes sense. It's a good little trick and can save you bucks.

[Bob Salomon]

Heliopan makes a full range of 105mm filters and hoods. They even make larger ones like 112, 127, 135mm

[Scott Walton]

Have you thought about mounting the filter to the rear element... usually smaller. Look on Ebay for B+W filters or go to Calumet and get one of those filter holders for gels for the rear inside mount. It is called Xenophon holder or even a Kenko Technical Holder but they only go up to 77mm and the Kenko isn't small. Go here to see the Xeno:http://www.calumetphoto.com/ctl?PAGE=Controller&ac.ui.pn=cat.CatItemDetail&ac.item.itemNo=XB6560&ac.cat.CatTreeSearch.detail=y&type=SPDSEARCH

[Ralph Barker]

You may actually want to use both, Al. For example, I have a HiTech resin/gel filter holder that I use with IR gels and ND grads, but use a couple of conventional glass filters more frequently. Remember, however, that the 4" gels are only 100mm - meaning you may get some vignetting once the holder is attached, depending on the construction and focal length of the lenses it's used on.