Schneider Super Angulon 72mm XL - filter conundrum

[daniel_taylor1]

just ordered the 72mm XL. rented one and loved it for my aircraft hangar interior work. the 95mm filter format presents an interesting question. how best to filter if needed? not sure it is a requirement, though I do love my #25 filter for cloudscapes? my thinking is to merely hold the Lee/Cokin filter in front of the lens. the Cokin holder vignettes with my 110mm XL, so I see no need to attempt this. even the X-series most likely does the same.

 

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suggestions?

[michael_briggs2]

If you decide you want to use the Schneider center filter for this

lens, the filter thread becomes 110 mm. What I do is tape 100 mm

square polyester filters (Lee or Calumet) to the lens.

[jim_chow]

I just hold the filter in front of the lens, careful not to get it in

the way when using front tilts. Tape will work, too. The problem w/

the Lee holders is that you risk vignetting w/ a wide lens.

[ellis_vener_photography]

Try taping the filter across the rear element. Attach one end of the tape strips the tape on the barrel of the lens. This works well with polyester, gel and resin

filters Alternately: cut a polyester/gel filter to fit inbetween the c.w.f. filter and the front element.

[masayoshi_hayashi]

There are some related threads discussed under Filter. Try <a

href="http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=001

6b6">this</a> for example.

[daniel_taylor1]

the previous threads reference a wide-angle holder that isn't listed

in my Lee catalogue. further investigation yields a divided opinion

as to whether or not the 95mm adapter ring will work with the

standard foundation kit. I was told 'no worries mate' by my

Australian pro-photo buds, but I tend to believe otherwise from

photo.net posts.

 

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trying to standardize on my filter system, and need one that will

support all lenses. not an easy choice apparently.

[larry_huppert1]

I doubt Lee would have gone to the trouble of making the FK-100

foundation kit for the 72XL & 90XL if a standard Lee adapter ring

would have worked. Apparently the part is fairly new, and isn't in

any of the catalogs. I've used a Lee WA adapter ring & foundation

kit holder with the 75 SA, and could see where it started to

vignette. Since the 72XL has a vastly larger image circle, I find it

hard to imagine that the standard 95mm adapter ring could work

effectively in all situations. If you don't use many movements, the

95mm adapter ring is probably OK (but if that's the case, why use the

big & expensive 72XL?).

[alan_gibson1]

For the 72, 58 and 47 XL lenses, I constructed cardboard holders for

100mm square filters. They hold the gels against the front rim, so

have no vignetting.

[daniel_taylor1]

thanks for the advice. the lens arrived and is beautiful. can't wait

to find some great light. I checked the Lee dealer, and the FK100 was

not listed in latest catalog. also, there wasn't a 95mm WA adapter

ring available. like Alan mentioned, a homebrew solution shouldn't be

too difficult to come up with. might as well put that machine shop of

mine to good use, instead of just working on airplanes! in addition,

after polling many 72XL owners about their solutions (some of them

quite comical), if I stumble onto something cheap that worke well, I

will publish the details.

[masayoshi_hayashi]

Daniel, B&H sells FK100 for about $150. I use optiflex resin filters

(0.3mm thick?, great for wide angle lenses) and recommend them.

[larry_huppert1]

Daniel,

I'd be particularly interested in any solutions which work with grad

filters (other than the FK-100).

[larry_huppert1]

I've done a quick visual test (no chromes or Polaroids yet) of the

72XL with the Lee FK-100 filter holder. My overall opinion is that

Lee has pretty much solved most of the problem of using 4" filters on

this BIG piece of glass.

 

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My estimate is that the 72XL without any filters attached allows

close to 50mm of rise with the ground glass in "portrait" position

before corners start to vignette. With the FK-100 attached and setup

for two filters, the worst possible case is loosing about 7 - 10 mm

of rise from the outer set of filter rails coming into view. If the

FK-100 is configured for only one filter, it didn't appear that you

lost anything. I consider the worst possible case to be where the

filter holder rails are perpendicular to the major direction of

movement. In this case, with portrait format and using front rise,

the worst possible case is with the filter rails are horizontal.

With most filters this isn't an issue because you can just rotate the

holder. It only becomes an issue with grad filters.

 

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(an aside: Filter rail stack height is critical to minimize if your

going to get the most coverage with WA lenses. Every millimeter

counts. The Lee system uses a fairly non-functional cap piece whose

only function is to allow the screws to sit flush. I throw out this

piece, and use a hand held wood working counter sink tool on the

outer rail pieces to allow the screws to sit flush without the extra

piece. Alternatively, you could just get some flat head screws. My

preliminary estimates above were with this modification.)

[kahheng]

Hi Dan

 

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You might consider using filters at the rear of the lens. I bought

some old new stock Sinar 3x3 filters recently and was finding a way to

mount them on my 67mm diameter lenses without causing vignetting.

 

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I posted a request for suggestions at RPELF on USENET and some clever

chap emailed me and suggested that I use Xenophon rear filter holders.

If you go over to Calumet's website http://www.calumetphoto.com, and

type "Xenophon" as the search string you will find them. They have

both 3x3 and 4x4 gel holders (picture available at the site).

 

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I am not sure how much rear mounting a filter would affect picture

quality (I haven't personally tried it yet).

 

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Hope this might help.

[larry_huppert1]

Does rear mounting a filter change focus?

 

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I remember seeing the "Xenophon" at Calumet, and thought it was

interesting, but quite a bit overpriced for what it was. It also

didn't appear to be an easy solution if you use multiple lenses,

unless you get a "Xenophon" for each lens. Changing the depth of the

holder to accomodate different lenses appeared to require a

screwdriver.

 

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At one time I thought about building a rear filter holder out of a

routed out piece of wood. I would also cut different length side

pieces to fit each of my lenses, and attach them to the block via

embedded magnets (velcro is too sloppy).

[bob_salomon3]

"Does rear mounting a filter change focus? "

 

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It does several things - none good!

 

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A: Any filter placed behind the lens (unless designed to be part of

the lens) creates a focus shift equal to 1/3 the thickness of the

filter.

 

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B: Any fingerprint will degrade the image

C: Any dust degrades the image

D: Any dirt degrades the image

E: Any smudges degrade the image

 

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In short there is no positive optical reason to place a filter behind

the lens.

[kahheng]

I buy the focus shift argument A if you are using filters that make

it inconvenient to focus with the filters on. But the problems with

B-E applies to front mounting as well! You have to exercise care to

make sure the filters are clean whether you mount them in front or

behind.

[bob_salomon3]

" But the problems with B-E applies to front mounting as well! You

have to exercise care to make sure the filters are clean whether you

mount them in front or behind."

 

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Not really since the image has passed through the lens and is then

"disturbed" by having to go through dust, dirt, fingerprints, etc.

[ellis_vener_photography]

Gee Bob, have you told the guys at Sinar this? They might need to know that so they can recall all of the Auto Shutters and Digital Shutters thay have sold

over the years. But I agree completely with you about the need for absolute cleanliness. The focusing difficulty is resolved by focusing with the filter in place.

[bob_salomon3]

"Gee Bob, have you told the guys at Sinar this? They might need to

know that so they can recall all of the Auto Shutters and Digital

Shutters thay have sold over the years. But I agree completely with

you about the need for absolute cleanliness. The focusing difficulty

is resolved by focusing with the filter in place. >

 

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You may not remember but when the shutter first came out that rear

mount was for gels not acrylics (which really didn't exist then.

 

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And whether or not Sinar has a rear mount does not mean it is a g

 

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ood place to put filter

[ellis_vener_photography]

Bob outside of the cleanliness issue (which is addressed by practicing good photo hygiene) and the focus shift issue (addressed by focusing with the filter in

place (or am I missing something else here?)) whta other issues would make this a bad idea? I ask this out of a case of genuine perplexedness as when I was

doing my apprenticeship this was a question that came up and was told that placing a filter there eliminates flare and some other issues. As you already know I

am a big fan of Heliopans glass filters so i am not trying to find a "cheap" solution".

[bob_salomon3]

Compendiums eliminate flare. And don't create focus shifts and don't

degrade the image due to the condition of the filter.

[ellis_vener_photography]

I agree about compendiums and I agree with you about everything else in your latest post Bob. Still I am curious as to whether or not there are other benefits.

Are there?<P>

Signed,<P>

Perplexed in texas

[bob_salomon3]

What other benefits do you want?

 

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Usin filters in front of the lens eliminates focus shifts and vastly

reduces image degradation (except from grossly defective filter).

Putting filters behind the lens creates focus shifts and does create

image degardation from marred filters. In addition flare occurs on

uncoated glass to air surfaces. if a non coated filter is behind a MC

coated lens flare can occur

[bob_salomon3]

Oh yes,

 

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They also protect the front element of the lens.

[don_wong]

One instance I've found advantageous for putting filters behind

the lens is when using multiple gels to correct artificial light color

to match transparency film.

 

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Multiple gels in front of the lens will cause ghost images of bright

light sources (such as HID lights in a gymnasium). I use 3" gels

for compactness, but they're too small to curve in front of the

lens.

 

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Rear lens elements are smaller than front ones, so the 3" gels fit

there, with room for some curvature of the gels. The curvature

removes the ghosts.

 

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There are problems with this method, but it's the best way I've

found to solve that particular ghosting problem.

 

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Don Wong