From: "Willem-Jan Markerink" To: eos@avocado.pc.Helsinki.FI Date sent: Thu, 16 Mar 2000 17:21:26 +0100 Subject: 24/3.5 TS-E & Cokin-P (was: EOS: What filters to use with wide a Priority: normal Send reply to: eos@avocado.pc.Helsinki.FI On 15 Mar 00 at 5:06, Bob Spitz wrote: > I have had difficulty posting to this list, so my apologies if multiple > copies of this message end up on the list. > > I have recently purchased a Canon 20-35mm f3.5-4.5 lens and am looking > at the 24mm f3.5L tilt-shift lens. I would like advice regarding brands > of filters that can be used with these wide angle lenses without > vignetting at the edges of the image. I often use more than a single > filter at once, such as a warm-up filter together with a graduated > neutral density filter. Does anyone make glass filters that are thin > enough to use two at once with these lenses. If so, I would plan to get > the 77mm filters for the lens I have, and get a 72-77 step up ring if I > purchase the tilt-shift lens. Are systems like Cokin, Lee, or HiTech > preferable? Any advice is greatly appreciated. I just went through all permutations with the 24/3.5 and a Cokin-P holder: - focused on infinity (worst-case scenario, close-focus decreases vignetting) - tilt & shift cross-axed (factory setting; when putting tilt & shift in the same axis, the vignetting effect would increase....effect of shift is worse than tilt though, so results might not change much): 1) Normal mounting, 72mm metal adapter: a) ears to the sides: massive vignetting with full tilt or full shift b) ears on top/bottom: very slight vignetting at full shift, no vignetting with tilt c) ears diagonal: vignetting with tilt and/or shift 2) Same as above, now with pol filter mounted: Slight vignetting at full shift, massive vignetting with tilt up/down and shift left/right, a bit less with tilt left/right and shift up/down (a/b/c distinctions as above are not relevant, the pol is more obstructive than the orientation of the ears, at least in the corners) 3) Recessed mounting, using the bayonet-shape of Canon hood (requires cutting the inside of the Cokin holder, see the bottom of this message): a) ears on the side: slight vignetting at full shift b) ears on top/bottom: no vignetting with shift or tilt c) ears diagonal: slight vignetting with tilt, massive vignetting with tilt & shift Btw, 'slight vignetting' means only at full tilt or shift, red area....2-3 stripes less (3 less=white area) is enough to solve the problem. Note that cutting off one slot is about equal to the recessed mounting option....cutting off two slots would create an even shorter holder, vignetting-wise. Yet only the 'minus-1' cutting allows a square filter in combination of a pol filter, while the recessed mounting doesn't allow a pol at all (unless one uses a homemade square one) Modification-instructions: xxxxxxxxxxxxxxxxxxxxxxxx From: "Willem-Jan Markerink" To: eos@avocado.pc.Helsinki.fi Date sent: Wed, 25 Aug 1999 23:13:18 +0100 Subject: Re: EOS: Cokin Filter System w/20mm lens (Off Topic) Priority: normal Send reply to: eos@avocado.pc.Helsinki.fi On 25 Aug 99 at 12:59, Roger Wojahn wrote: > I searched the archives and read that the Singh-Ray graduated filter > system, which uses the Cokin holders, shows vignetting with the 20mm > lens unless one cuts off the last one or two slots. > > Is this still the case? In landscape mode, a graduated filter will have to be used with the 'ears' of the filter holder on the sides, instead of in the least vignetting position (ears on top and bottom). Solution depends a bit on whether you want to use a polaroid filter as well....if not, you can leave the holder basically intact, by cutting out the the inner plastic circle on 3 spots, to match the bayonet-hood shape on the lens....it will snap right down, and stay fixed after rotating. Best way of cutting IMO is with a hot soldering iron. Also note that it will then also fit the 24/3.5 TSE, and the 20-35/2.8 (I think)....all use the same shape of bayonet for the hood attachment. xxxxxxxxxxxxxxxxx -- Bye, Willem-Jan Markerink The desire to understand is sometimes far less intelligent than the inability to understand [note: 'a-one' & 'en-el'!] From: "Willem-Jan Markerink" To: eos@avocado.pc.Helsinki.FI Date sent: Thu, 16 Mar 2000 16:27:38 +0100 Subject: Re: EOS: Re: Re: What filters to use with wide angle lenses? Priority: normal Send reply to: eos@avocado.pc.Helsinki.FI On 16 Mar 00 at 3:19, Julian Loke wrote: > >> Julian Loke responds: > >> The Cokin P system (83mm width) will cause vignetting on my EF 24 > >> f/2.8 when the holder is rotated to a diagonal position. ... > > Gary Russell wrote: > > ... My new EF 20-35 f/3.5-4.5 shows visible vignetting through the > > camera's viewfinder when used with the Cokin P sytem and the lens is > > at 20mm. ... I'll check into Lepp's suggestion on modifing the > > filter holder (thanks Julian) as I have only been using one filter > > at a time anyway. > > Hi Gary, > > Willem-Jan had some way of modifying the Cokin P plastic clip so > that it could fit directly on the bayonet mount of an EF 20mm f/2.8 > (and I think the EF 24mm f/3.5 TSE L too? C'mon WJM, help me out > here). But he had to use "two right hands and a soldering iron". > See: Not sure if this is the one you mean xxxxxxxxxxxx From: "Willem-Jan Markerink" To: eos@avocado.pc.Helsinki.fi Date sent: Wed, 25 Aug 1999 23:13:18 +0100 Subject: Re: EOS: Cokin Filter System w/20mm lens (Off Topic) Priority: normal Send reply to: eos@avocado.pc.Helsinki.fi On 25 Aug 99 at 12:59, Roger Wojahn wrote: > I searched the archives and read that the Singh-Ray graduated filter > system, which uses the Cokin holders, shows vignetting with the 20mm > lens unless one cuts off the last one or two slots. > > Is this still the case? In landscape mode, a graduated filter will have to be used with the 'ears' of the filter holder on the sides, instead of in the least vignetting position (ears on top and bottom). Solution depends a bit on whether you want to use a polaroid filter as well....if not, you can leave the holder basically intact, by cutting out the the inner plastic circle on 3 spots, to match the bayonet-hood shape on the lens....it will snap right down, and stay fixed after rotating. Best way of cutting IMO is with a hot soldering iron. Also note that it will then also fit the 24/3.5 TSE, and the 20-35/2.8 (I think)....all use the same shape of bayonet for the hood attachment. xxxxxxxxxxxxxxxxxxxxxx > The disadvantage of WJM's method is that the round filter slot > is destroyed. And I just got the Cokin Circular Polarizer too!. Nothing destroyed, the normal metal adapters still fit.... > But Lepp's method also destroys two of the three clips :-( Surely > there must be some way of "thinning" the clip so that it holds the > rectangular filters only by the corners and not by the sides :-) The Cokin holders are not that expensive....sacrificing one isn't a big deal, just more hassle in taking them with you....but then again: all my lenses have their own Cokin holder attached, for mechanical protection. -- Bye, Willem-Jan Markerink The desire to understand is sometimes far less intelligent than the inability to understand [note: 'a-one' & 'en-el'!] From: bart.kupers@transport.alstom.com Subject: EOS: Pinout of Technical Back E connector? To: eos@a1.nl Date sent: Fri, 19 Apr 2002 11:09:11 +0200 Send reply to: eos@a1.nl Hi all, I want to connect my Technical Back E to a PC. On WJM's homepage I found a link to a little program, written by Micheal Rothe, that would allow me to do just that. With the program comes a drawing that explains how to build the necessary IFU-interface yourself. Unfortunatelly, the drawing only refers to the colors of the various wires on the TBE-connector cable, but does not explain how the pins (Rx, Tx, RTS, CTS and Ground) are arranged on the connector. Could anybody (Pawel Nabe?) tell me? I would hate to open the TBE or the Keyboard (the previous owner has already wrecked one or two of the screws, so it would be quite difficult anyway), just to see what colors go where... Thanks! Bart PS: Fellow-listmember Jeff Holcombe has sent me scans of his manuals, so I can now start to work on the TBE-manual for the eosdoc-page! Date sent: Wed, 24 Apr 2002 01:30:07 -0700 From: "John H. DuBois III" To: eos@a1.nl Subject: EOS Re: Pinout of Technical Back E connector? Send reply to: eos@a1.nl On Fri, Apr 19, 2002 at 11:09:11AM +0200, bart.kupers@transport.alstom.com wrote: > I want to connect my Technical Back E to a PC. On WJM's homepage I found a > link to a little program, written by Micheal Rothe, that would allow me to > do just that. With the program comes a drawing that explains how to build > the necessary IFU-interface yourself. Unfortunatelly, the drawing only > refers to the colors of the various wires on the TBE-connector cable, but > does not explain how the pins (Rx, Tx, RTS, CTS and Ground) are arranged on > the connector. ______ / a b \ | ( ) c d | | ( \_e__f_/ )( = keys a: black b: white c: NC d: blue e: green f: red John -- John DuBois spcecdt@armory.com. KC6QKZ/AE http://www.armory.com./~spcecdt/