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Thread: Centerfilter for Schneider 35mm XL Apo-Digitar

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    Centerfilter for Schneider 35mm XL Apo-Digitar

    I just purchased an Schneider 5,6/35 XL Apo-Digital for my Cambo RS1000. Trying to find out if I need the centerfilter when shooting with a digital back (P45)?

    I have done some reading about the centerfilter. Some say it is needed. Some say, no need.

    Anyone have any experience with this lens and centerfilter?

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Love the lens. Not using a center filter BUT I'm on a P40+ crop sensor.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Tim - I have a Schneider 35mm as well and initially shot it without the filter however I bought the filter and haven't removed it in over 18 months. I feel it's well worth the expense.

    Don
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by Don Libby View Post
    Tim - I have a Schneider 35mm as well and initially shot it without the filter however I bought the filter and haven't removed it in over 18 months. I feel it's well worth the expense.

    Don
    I have the exact opposite experience. I bought the lens with a centre filter and religiously used it for a while.
    Then, it occurred to me that LCC in C1 does exactly what the centre filter does, without adding anything in the light path that might degrade image quality and giving me back the stop-and-a half of light it cost me.
    I haven't used it since. I have stopped using centre filters with all my tech-cam lenses now.
    Cheers,
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    I try to do as much as possible in camera to get the most optimal exposure possible, and as such I find center filters very useful (on a P45+ size sensor). Remember LCC in C1 is a fine tool, but it isn't a magic bullet; it's simply pushing the edges to match the center. If the edges are a bit noisy anyway (dependent on your original exposure), pushing them another couple of stops isn't the best thing to do. Just my 2c.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    I use a CF with large movements for the same reason: avoiding noise at the edges.
    It certainly also depends on the sensor... for the P45 I feel 2 stops exposure compensation based on software correction is too much.
    Alternatively you can shoot multiple exposures... i.e. one shot exposed for the center of the image circle and another exposed for the edges of the image circle. But post work can be complicated then.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    You'll still need to shoot a LCC (at least I do) with a CF. I enjoy using the CF with the 35mm for the image it gives me rather than what I got without it. Better image from the start and less problems in post.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by Don Libby View Post
    You'll still need to shoot a LCC (at least I do) with a CF. I enjoy using the CF with the 35mm for the image it gives me rather than what I got without it. Better image from the start and less problems in post.

    Don
    I agree. The CF doesn't completely level out the light falloff but it's much easier to fix in post.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by Don Libby View Post
    You'll still need to shoot a LCC (at least I do) with a CF. I enjoy using the CF with the 35mm for the image it gives me rather than what I got without it. Better image from the start and less problems in post.

    Don
    Don, what are the problems you are having in post when you don't use the centre filter? I'm not trying to be cute, I'm genuinely interested.
    Cheers,
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by siebel View Post
    Don, what are the problems you are having in post when you don't use the centre filter? I'm not trying to be cute, I'm genuinely interested.
    Cheers,
    Siebel, good question and I understand you're not being cute.

    Using a centerfilter on my 35mm gives me better color and less caste however the operative word is "less" as you still need to shoot a LCC for post.

    I could achieve the same finished image without the centerfilter knowing I'd still have to shoot an LCC and the post processing would be slightly more involved than if I use the centerfilter, shoot the LCC and have less processing involved in getting to the same end. For me using a centerfilter gives me a better image file and at the same time easier to fix in post.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    My understanding of lenscast is that it is primarily a function of the angle at which light strikes the sensor. The more obtuse the angle, the more severe the cast. (This is a generalization. You will in fact notice bands of colour shift as you move towards the outer edge of the image circle. It is not a continuous shift).
    Assuming this to be correct, then a centre filter should have no effect whatsoever on lenscast. It is designed to reduce illumination falloff.
    The LCC function in C1 combines 2 algorithms - one to correct lenscast, neutralizing the colour shift, and the other to correct illumination falloff. There are sliders to control how completely you want to do this.
    My own experience with shooting a LCC frame through the diffuser after each series of shots at a given shift would suggest that both colour cast and falloff are fully corrected even when using no centre filter. (Within a range of tolerance. When you start pushing local contrast as I do in most of my work, you will start to notice some small amounts of uncorrected cast).
    The only circumstance I can see where using a centrefilter might help is if the level of falloff from centre to edge is so extreme that it is beyond the adjustment range of the software. The performance of this lens is not that bad, even at f8-f11 where I do most of my work.
    As the process of using the LCC software is the same whether you use the centrefilter or not, I'm a little confused about your approach, Don. Am I missing something?
    Perhaps Doug and Yair might like to share some wisdom?
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Not using a center filter with my 35mm, but like Terry that's with a P40+. With the 24mm it's really necessary. If you are in a situation where you need all the dynamic range a MF back can give you across the entire sensor then I would think a CF is a good idea. When you "invoke" the LCC correction with the 35mm on a P40+ you lose about a stop (maybe 1.5?) of DR because the levels on the edges need to be higher. The amount of lens cast (not exposure) does not seem to depend on the use of a center filter.
    In a nutshell, I have been using the 35mm and not had a situation where I needed a center filter, but I am sure it is out there waiting for me....
    This topic was kicked around a few months ago and at least one poster thought that they had some image degradation with a center filter... I haven't noticed that with my 24mm XL... it was still so sharp it made my teeth chatter. If Don Libby thinks it's a good idea to use one it is probably worth re-examining... even with a 35mm. Really comes down to how much you can bring up your edges without getting noise problems.
    Betcha Doug can nail down all these mysteries in a single post.
    Last edited by ggriswold; 15th February 2011 at 03:01.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by siebel View Post
    Am I missing something?
    yes, noise.
    A software based push of exposure (at the edges in the case of LCC based light falloff correction) results in an effective increase of ISO. So shooting at ISO50 with a lens that shows a light falloff of 2 stops at the edges results in an image with ISO50 in the center and ISO200 at the edges (simplified speaking).
    The use of a glass filter does reduce the amount of correction needed in post. Therefore the edges are cleaner (with regard to noise).

    Quote Originally Posted by siebel View Post
    a centre filter should have no effect whatsoever on lenscast.
    just a side note: a CF may introduce additional color cast. The sensor cast (i.e. the color cast we normally call "lens cast") goes from cyan to magenta whereas a CF in fact may introduce lens cast ... and this one goes from blue to yellow. Former versions of Capture One couldn't correct this color cast flawlessly all the time but since version 4.8 (IIRC) the correction of both sensor and "lens" cast is corrected perfectly.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Has anyone ever tried the SCHNEIDER DIGITAL CF ? ? ?
    They are obviously created by NURIZON DIGITAL as CF plugins for PSCS2 and newer .
    http://www.digitalcenterfilter.com

    The description is in english and german language .
    You will also find information on the SCHNEIDER home page .

    I have not used any of them so far , but would like to hear if anyone has experience .

    I also believe , if you do not use a full "frame sensor back" you will not get very much vignetting anyway and the rest can easily be corrected in PHOCUS .
    Sorry , I don't know of C1 but believe that function is available there too .
    Regards . Jürgen .
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by ggriswold View Post
    Not using a center filter with my 35mm, but like Terry that's with a P40+. With the 24mm it's really necessary. If you are in a situation where you need all the dynamic range a MF back can give you across the entire sensor then I would think a CF is a good idea. When you "invoke" the LCC correction with the 35mm on a P40+ you lose about a stop (maybe 1.5?) of DR because the levels on the edges need to be higher. The amount of lens cast (not exposure) does not seem to depend on the use of a center filter.
    In a nutshell, I have been using the 35mm and not had a situation where I needed a center filter, but I am sure it is out there waiting for me....
    This topic was kicked around a few months ago and at least one poster thought that they had some image degradation with a center filter... I haven't noticed that with my 24mm XL... it was still so sharp it made my teeth chatter. If Don Libby thinks it's a good idea to use one it is probably worth re-examining... even with a 35mm. Really comes down to how much you can bring up your edges without getting noise problems.
    Betcha Doug can nail down all these mysteries in a single post.
    George I just shot the Alpa TC with 24mm XL all week with my P40+ and yes you absolutely need the center filter with it. As far as degradation I did not notice anything obvious since the images are very sharp with the filter on and you also need a LCC for sure.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by thomas View Post
    yes, noise.
    A software based push of exposure (at the edges in the case of LCC based light falloff correction) results in an effective increase of ISO. So shooting at ISO50 with a lens that shows a light falloff of 2 stops at the edges results in an image with ISO50 in the center and ISO200 at the edges (simplified speaking).
    The use of a glass filter does reduce the amount of correction needed in post. Therefore the edges are cleaner (with regard to noise).

    just a side note: a CF may introduce additional color cast. The sensor cast (i.e. the color cast we normally call "lens cast") goes from cyan to magenta whereas a CF in fact may introduce lens cast ... and this one goes from blue to yellow. Former versions of Capture One couldn't correct this color cast flawlessly all the time but since version 4.8 (IIRC) the correction of both sensor and "lens" cast is corrected perfectly.
    Hmm. Good point, the theory seems sound. I wonder if the fact that I often only partially correct falloff is hiding the noise artefact you describe. I'll run some tests. Just out of curiosity, what back are you using?
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by siebel View Post
    Hmm. Good point, the theory seems sound. I wonder if the fact that I often only partially correct falloff is hiding the noise artefact you describe. I'll run some tests. Just out of curiosity, what back are you using?
    it depends on the subject, the amount of movements applied and of course also on the sensor whether or not a CF is useful. Also on the lenses, naturally. Without or just little movements I don't use a CF; with large movements I do.
    I use a P45 and of course with this ancient sensor noise is something to care about. However, Chris B. (of whom I think he is very demanding re IQ) also has noise issues even with a P65+ -> http://forum.getdpi.com/forum/showthread.php?t=16966

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by jotloob View Post
    Has anyone ever tried the SCHNEIDER DIGITAL CF ? ? ?
    yes, with my 43XL.
    IMO it's a very weak tool. The images are undercorrected, the plugin increases contrast at the edges (and therfore also saturation) and ... actually the most important downside... it works gamma-dependent (i.e. the correction of a file in AdobeRGB with Gamma 2.2 is different to the correction of a file in ProPhotoRGB with Gamma 1.8).
    The falloff correction is also only based on lens data. But in pratice different sensors produce different falloff. Therefore the correction based on a white reference shot (as provided in C1, Phocus etc.) is much better.
    Finally the plugin is quite slow.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    For the benefit of folks who may not have all these lenses to see the falloff I have photographed 4 LCC plates (Capture Integration.. $20 perfect size includes nifty wrist strap) for:

    45mm Rodenstock. No Center Filter
    35mm Schneider APO- Digitar XL No Center Filter
    24mm Schneider APO- Digitar XL With Center Filter
    24mm Schneider APO-Digitar XL NO Center Filter

    Shot at f16 the first two, the 24mm at f11.
    Imported into Lightroom, eye dropper white balanced and center levels brought up to 78_78_78 %
    Obviously you would want to use Capture One to correct the files, but you can see how much fall off there is with the 24mm without the center filter... I never take mine off for that reason.
    I am not the right guy to tell you how much fall off there is in each in terms of f-stops.
    Last edited by ggriswold; 21st July 2013 at 08:35.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by ggriswold View Post
    I am not the right guy to tell you how much fall off there is in each in terms of f-stops.
    not sure if the indication is accurate based on a JPG... but it seems the falloff is at least 4 stops on the 24XL without CF:

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Using the "call out" values function in Capture One...
    Here are 4 screen grabs from the upper right corner of each of the 4 shots with some RBG numbers...
    (That trip to Atlanta last week for the Capture Integration workshop was worth it!)
    Last edited by ggriswold; 21st July 2013 at 08:35.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Sorry I missed the party but thomas has it all right.

    Advantages of not using a CF:
    - no loss of light
    - no loss of optical quality (no additional glass)
    - slightly lighter rig

    Advantages of using a CF:
    - you can even out the lens falloff with less chance for noise
    - LCD preview in-camera is more accurate to final product

    Any use of LCC constitutes "pushing" the file around. "Pushing" a file, by definition, increases noise; the more relevant question is "how much?".

    Fortunately Phase/Leaf files exposed reasonably well at base ISO will take an enormous amount of abuse without showing problems. If, however, you're already using higher ISOs, or you already underexposed the file, or you are towards the limit of the maximum length of exposure for your back, or if you are really really anal about noise, then even a bit of pushing around will start to show meaningful noise.

    The "party line" is that LCC can correct for "about 2 stops" of light-falloff. My statement mirrors this party line, with the addition of "but do your own testing".

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Here is another consideration... there is debate if you should shoot new LCC plates on each location and use them just for that session. Others had good results with saved LCC corrections. I shoot them fresh each time if for no other reason than I have dust correction plates ready just in case picked up some crud during a lens change. If I do a rise/ fall or shift I always shoot a LCC plate even if is an often repeated amount.. say 5mm.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    and what happens when you shoot LCC plate and you find out that there's a bug in capture one with your particular back and LCC options... ;-(

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Archivue... have you had this problem? If the LCC doesn't work, then re-shoot or start a support case. If you are having Capture One problems you ma want to try a complete un-install. Maybe you are a Leaf back user and are having problems? Just trying to throw out some ideas....
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by archivue View Post
    and what happens when you shoot LCC plate and you find out that there's a bug in capture one with your particular back and LCC options... ;-(
    What's the bug?
    Have you created a case with Phase One?
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Probably should create new thread if you have an issue.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by ggriswold View Post
    Probably should create new thread if you have an issue.
    I suggest you create a thread on the Phase One users website. You'll get a meaningful answer straight up.
    Cheers,
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Apologies for the

    Actually there is a thread (& open support case) over at Phase One regarding this LCC problem with Leaf Aptus 65/75 uncompressed/compressed file crashes & C1 Pro v6.1 & v6.1.1. It may apply to other Leaf backs too but these two I know about.

    If this is your issue, the current solution until Phase One fix it is to revert to v6.01. or use Leaf Capture for now for LCCs.

    Of course if this isnt the same issue then definitely open a support case. Although I don't have a fix for my problem yet, the Phase One folks have been very responsive and worked with me to help identify, validate and hopefully soon fix the issue. Bugs happen but how a company responds to them is just as important and so far Phase One have passed my initial sniff test on this.

    for Phase One support. for the bug though.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Just ordered this center filter from CI. I can't seem to find out what size the filter threads would be at the end of this center filter. It would seem that it would be larger than the original to allow for movements. Could someone clue me in on that?

    Mason.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    The Schneider IIF center filter threads are 72 x .75 mm.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Thank You Steve.

    Mason.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by dougpetersonci View Post
    Sorry I missed the party but thomas has it all right.

    Advantages of not using a CF:
    - no loss of light
    - no loss of optical quality (no additional glass)
    - slightly lighter rig

    Doug Peterson
    Doug:

    Can you show the loss of quality when using a center filter? I am interested in seeing the impact.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by Shashin View Post
    Doug:

    Can you show the loss of quality when using a center filter? I am interested in seeing the impact.
    The loss of quality is largely theoretical. In the real world, you will see no difference, unless you allow the two additional lens-to-air surfaces to get dirty.
    The two CF filters I have (one Rodenstock and one Schneider)do cause a small amount of vignetting on the widest lenses.
    The flare-suppression coatings are superb.
    Note that using a CF does reduce the amount of lenscast slightly, so those having issues with Shcneiders on the 5.2micron sensors should be aware of this. The other big benefit is that the LCC software does not have to make as big a correction due to a lot of the falloff already being corrected. As such, there is less residual artifacting.
    Phase are also working hard to improve the algorythm.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    I happen to have the CF for this lens listed in the B&S at the moment -- as new for $200 shipped US. FWIW, it is the 2*G* that is correct for the 35 XL APO Digitar. As has been said, advantages are it eases the load on C1 for the LCC and most especially, eliminates the excess noise at the edges from said lifting. I have never noticed any loss of image quality from using one, though I suppose it's there in some minor form.

    http://forum.getdpi.com/forum/showthread.php?t=28365
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Just to avoid any confusion, there are two CFs available for the 35mmXL A/D:

    Centre Filter IIf 52/72
    4x/2 stop Centre Filter that screws into the 52mm filter thread on the front of the 35mm XL lens

    Centre Filter IIg 67/72
    4x/2 stop Centre Filter that screws into the 67mm filter thread on the front of the panel in pre mounted 35mm XL lenses

    The IIf is the most common one - I had it for the 35mm XL A/D in Cambo mount. Definitely needed with the 35mm XL A/D. Not sure I've ever seen a 35mm XL A/D with a 67mm front thread - maybe an Alpa variant or similar?

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    Subscriber & Workshop Member GrahamWelland's Avatar
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by f8orbust View Post
    Not sure I've ever seen a 35mm XL A/D with a 67mm front thread - maybe an Alpa variant or similar?
    My Alpa mount Schneider 35 XL Apo-Digitar is 52mm and takes the IIf. The Apo-Switar variant from Alpa (same optics) has the 72mm filter thread and requires a IIa filter.
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    Workshop Member Wayne Fox's Avatar
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by Jack Flesher View Post
    I happen to have the CF for this lens listed in the B&S at the moment -- as new for $200 shipped US. FWIW, it is the 2*G* that is correct for the 35 XL APO Digitar. As has been said, advantages are it eases the load on C1 for the LCC and most especially, eliminates the excess noise at the edges from said lifting. I have never noticed any loss of image quality from using one, though I suppose it's there in some minor form.

    http://forum.getdpi.com/forum/showthread.php?t=28365
    To me the real issue of whether to use a CF or not is if you want to give up 2 stops or so of your sensors dynamic range.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by Wayne Fox View Post
    To me the real issue of whether to use a CF or not is if you want to give up 2 stops or so of your sensors dynamic range.
    Actually, you will be giving up 2 stops of exposure, but increasing the dynamic range available to the LCC software as it has to do less work to correct brightness falloff. It will be primarily using up DR to adjust colour cast not density. This is why corrected files show less noise at the edges when the starting point is a file that was shot with a centre filter.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    True, but you still loose 2 stops in exposure time. So at dawn it can be a problem, if you need 90 seconds instead of 30.

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by siebel View Post
    Actually, you will be giving up 2 stops of exposure, but increasing the dynamic range available to the LCC software as it has to do less work to correct brightness falloff. It will be primarily using up DR to adjust colour cast not density. This is why corrected files show less noise at the edges when the starting point is a file that was shot with a centre filter.
    Not sure ... are we sort of saying the same thing? My point is that if you do not use a center filter, two stops of your sensors dynamic range will be lost in the fall off. If you do use a center filter, then you will have to increase exposure by two stops when you use it, but now the light falling on your sensor has been somewhat adjusted so you now can capture more of the dynamic range of the scene.

    There are many occasions where not using a center filter can be very problematic, where the center of the image is already many stops brighter than the edges, such as sunsets etc. Without a center filter you may not be able to capture a full dynamic range adequately.
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Seems to me that Wayne and Bryan are saying the same thing and agreeing with each other.

    What I can add is that my 35 XL is probably arguably the sharpest lens I own and I LOVE it! I just bought the center filter myself too although with the P40+ crop it's not quite so critical. The infinity focus is somewhat different to my other lenses due to the fact that it doesn't hard stop at that point (I know that's so that you can adjust for the center vs edge focus) but I've grown to really really like this lens.
    Remember: adventure before dementia!

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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Quote Originally Posted by siebel View Post
    Actually, you will be giving up 2 stops of exposure, but increasing the dynamic range available to the LCC software as it has to do less work to correct brightness falloff. It will be primarily using up DR to adjust colour cast not density. This is why corrected files show less noise at the edges when the starting point is a file that was shot with a centre filter.
    Quote Originally Posted by GrahamWelland View Post
    Seems to me that Wayne and Bryan are saying the same thing and agreeing with each other.

    What I can add is that my 35 XL is probably arguably the sharpest lens I own and I LOVE it! I just bought the center filter myself too although with the P40+ crop it's not quite so critical. The infinity focus is somewhat different to my other lenses due to the fact that it doesn't hard stop at that point (I know that's so that you can adjust for the center vs edge focus) but I've grown to really really like this lens.
    Unfortunately, I think it's a no go on the IQ180 ... very strange color casts, far more than I'm comfortable with. Problem is the color casts are all through the image, not limited to the corners. I"m all for LCC's, but at some point it's too much data manipulation and compensating too much for one thing means losing something else somewhere.

    The lens was much better on the p65.
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    Member Chris Barrett's Avatar
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Adding fuel to the fire... My introduction to the IQ180 was 9 days ago at 5am. I didn't have a whole lot of time with it and I was trying to help lead a PODAS workshop at the time... so my testing was not in depth by any means. I threw the 35mm XL on my Rm3d, shifted it 15mm to the left and let it fly. The resulting LCC image was so frightening and that combined with reports here caused me to drop the IQ180 from my consideration without further exploration.

    Now that I've got a few days off and am still haunted by the awesomeness of the IQ GUI, I've begun to re-explore that test. The P65+ and the P45+ before it have been so good to me that I feel I owe the brand a little more generosity.

    Now, again, this was with the Schneider Apo-Digitar 35mm XL (which everyone says should NOT be used with the IQ 180), the camera is shifted 15mm (5mm more than anyone should really EVER shift this lens) and there was no Center Filter.

    The two images are captures from the IQ180 (left) and then the P65+ (right). You'll notice I had the IQ180 ISO set to 100. Why? It was 5am and there was no coffee in sight!

    I set the P65+ Light Falloff Correction to 56% because that's where I liked it esthetically (I typically back this correction off some to increase image depth). The IQ180 Light Falloff Correction is set to 73% to achieve corner readouts comparable to the P65+. 17% more correction... not too bad. It is obvious the IQ180 develops more fall off than the P65+ (which has more falloff than a P45+).

    I would have absolutely no issues delivering either file to a client (if, ya know, it was a decent composition with better light). The over-shifted composition with the new WAT LCC on the IQ 180 at 73% correction has no issues to my eyes.

    So how do I feel about everything now? I think I was too quick to dismiss the IQ180. It does provide just amazing detail, nicer clarity than the P65+ and allows for Big *** Prints. This hasn't convinced me to trade in my P65+ right away, but it has convinced me to do more real world testing. I especially want to see the difference with images that are inherently darker and see if corner noise is an issue.

    I dig the little Schneider 35mm and I really love my 43mm and am not anxious to swap those out for the big, heavy and pricey Rodie HR's to solve falloff on the IQ180. But if I can integrate the new back into my current kit, I think I'll be a happy camper.


    *All conclusions and opinions above are purely subjective and I have been known to be wrong about **** on occasion.






    CB

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    Workshop Member Wayne Fox's Avatar
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    Re: Centerfilter for Schneider 35mm XL Apo-Digitar

    Chris,

    One issue is there is a very wide disparity between IQ180's and Lens Cast. I've been working with 2, and my dealer has sent me LCC's from a third, and they are all completely different. The first one wasn't even acceptable on the DF. Second one is better, but the dealer's is better than mine. With the 55LS on the DF, his shows no color change from top to bottom, just some expected density falloff, min shows a magenta/green shift from top to bottom. His LCC on the 35xls isn't great, but better than my current one. So if you are shooting a Tech camera, some will perform better than others.

    I've heard from several sources that Phase is working on the issue, but seems it's probably more about the sensor and how it's stitched, so it may be just how things are going to be. I'd be curious to see the LCCs from those two shots.
    wayne
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