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Thread: Do I really need shims for Alpa 12 V Adapter?

  1. #1
    wgcho
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    Do I really need shims for Alpa 12 V Adapter?

    Hi GetDPIers,

    My first post here. I have ordered an Alpa 12 TC outfit and have an option to purchase an old shim-less adaptor for my CFV-39 back. The price difference for the adapter is about $750, so I am wondering if i really need the shims or not.

    I understand it could be useful depending on my lens, but the question is, if I rarely focus infinity - meaning I mostly use hyperfocal distance focusing for landscape work, and somewhat close to mid range for handheld street photography - do I really need the shims to adjust for infinity? My understanding is that even if the back is too close to the lens, far objects will still come out sharp as long as closed down and focused at a hyperfocal distance. Is this correct?

    Thanks!

    -Ted

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    Subscriber & Workshop Member GrahamWelland's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    If you are relying on zone focus then the shims won't be so critical. You won't be able to guarantee that infinity is set correctly or have total accuracy with the lens markings but that won't be so critical if you are stopped down at f/8 - f/16 anyways (unless close up of course).

    The main thing I find is that having my Alpa plates shimmed for my P25+ & IQ160 backs independently means that I have peace of mind that when I focus at distance X it really is in focus at X.

    I'd recommend that you go through the iterative process of determining your focus zones at the different f-stops if you want to achieve the acceptable DoF for your back for hyperfocal shooting with infinity still sharp. If you do this you'll know where to focus on YOUR lens/back combination at say f/8, f/11 etc that get you from the foreground (and where that is) through to infinity.
    Remember: adventure before dementia!

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    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    hi Ted,

    I agree with all what Graham says, but nothing is worth more than having peace of mind when one cannot afford to miss the image.

    For precise details on how to shim I suggest to watch this:

    Alpa adjustable back adapter

    Best regards
    Thierry

    Quote Originally Posted by GrahamWelland View Post
    The main thing I find is that having my Alpa plates shimmed for my P25+ & IQ160 backs independently means that I have peace of mind that when I focus at distance X it really is in focus at X.
    Thierry Hagenauer
    [email protected]

  4. #4
    wgcho
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Graham,

    Thanks for the suggestions. Sounds like a good calibration excercise to overcome the back distance problem without using shims!

  5. #5
    wgcho
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Hi Thierry,

    Yes, I already watched that video. I could really see the difference, but I kept wondering if it would be necessary for my use case. By the way, I don't understand why this problem is only spefic to digital backs. Shouldn't film backs have the same problem?

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    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Ted,

    It always depends what you expect to get out of the camera you are using, or put in a different way, you choose your camera depending on your needs and expectations.

    In your case you are using a camera manufactured with the highest possible precision and allowing the highest possible precision in your settings, e.g. when setting focus.

    I would definitively want my camera to perform at the maximum possible, even if I know that I won't possibly need such a precision.

    To answer your second question: film has a certain thickness which is forgiving to a certain point when it comes to focus, a digital sensor is not. The focus has to hit the sensor plane to get maximum sharpness.

    Best regards
    Thierry

    Quote Originally Posted by wgcho View Post
    Hi Thierry,

    Yes, I already watched that video. I could really see the difference, but I kept wondering if it would be necessary for my use case. By the way, I don't understand why this problem is only spefic to digital backs. Shouldn't film backs have the same problem?
    Thierry Hagenauer
    [email protected]

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    Re: Do I really need shims for Alpa 12 V Adapter?

    There are a lot of claims about the difference in focal plane between digital and film, but little evidence--ironically a test between an 8x10 film camera and an IQ180, there was an outcry that the focus was not done well enough for the film camera, so I guess it is not easy to focus film either. I use a MFD on a Linhof C679 and focus that as easily as I focused any film camera.

    The Alpa shimming is done at infinity, which is a strict test as you cannot focus beyond infinity--btw, if you set infinity at a mile of so, that may not be infinity for the moon, it is too close and can show. It also does not account for changes in camera temperature--Alpa does not suggest shimming for different ambient temperatures, but the camera will not be the same at 90 degrees as -40, which is the annual temperature swing in Maine. But you are right that shimming is not really needed for the zone focusing you will be doing. If you need accurate focus, you can use a ground glass which should be more accurate than a lens focus scale.

    I find that Alpa stresses precision too much. Ironically, while they emphasis the precision of their cameras, they also require their customers to then adjust the camera for imprecision. I think Alpa cameras are really fine instruments. Except for some extreme tests like the one for the infinity stop, I have not seen anything to suggest their criteria for precision is important and nothing I have experienced shoot large-format film and MFD suggests that photography suddenly needs this superhuman precision. I assume you have used your back on a Hasselblad, was it hard to focus?

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    Re: Do I really need shims for Alpa 12 V Adapter?

    you have to do two things:

    shim the back to make sure one lens, when at the inf stop, is producing as sharp an image as it can.
    then you have to adjust the inf stops on all your other lenses so they will also be in sharp focus at inf.

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    Subscriber & Workshop Member GrahamWelland's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    That's true - there can be variability in the lenses too. I had to have my Rodenstock 90-HRW adjusted to match all of my schneiders.(35/47/150).

    However, once it's done, it's done. Despite all the high prices of this stuff it's surprising the amount of tweaking required to cater for the variability of the back & sensor plane, the plate and all of the lenses. That said, many of us had similar experiences with Leica M glass too.
    Remember: adventure before dementia!

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    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Shashin,

    With all due respect I need to correct you here:

    It is not the Alpa camera which needs to be adjusted, you may have misunderstood the whole issue. It is the position of the sensor in the casing, which is often enough not what can be expected or what it should be, or then the lens precision. Differences of shimming or not can be shown easily in a side by side comparison.

    Nobody has never made the claim that an Alpa camera produces a "superhuman" precision, simply the precision required for backs with the pixel density and pixel size like one finds them today.

    Just for the record.

    Best regards
    Thierry

    Quote Originally Posted by Shashin View Post
    ... I find that Alpa stresses precision too much. Ironically, while they emphasis the precision of their cameras, they also require their customers to then adjust the camera for imprecision. I think Alpa cameras are really fine instruments. Except for some extreme tests like the one for the infinity stop, I have not seen anything to suggest their criteria for precision is important and nothing I have experienced shoot large-format film and MFD suggests that photography suddenly needs this superhuman precision. I assume you have used your back on a Hasselblad, was it hard to focus?
    Thierry Hagenauer
    [email protected]

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    Workshop Member Woody Campbell's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    The ability to shim is one of the key advantages of the Alpa. I've had two backs (an HR 60 and an IQ 180) and the shimming setup turned out to be quite different - the setup for the HR 60 was noticeably out of focus with the 180. I scale focus (with the Alpa HPF rings) so without shimming I could always be wrong. The final adjustment with the thinnest shim actually produces a just noticeable difference.

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    Re: Do I really need shims for Alpa 12 V Adapter?

    "The ability to shim is one of the key advantages of the Alpa.


    it often goes unsaid that the cambo can also be adjusted...not with shims, but with a fairly simple built in screw adjustment
    Last edited by jlm; 7th April 2012 at 10:19.

  13. #13
    wgcho
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Living in a different time zone (in Korea now), this is a great way to wake up - to find lots of useful information about the problem I'm dealing with. GetDPI rocks! Thanks for the all the comments~

    I'm still not sold on the idea that Digital Backs have more severe focusing issues. As Shashin pointed out, I never really had any problems using it with a Hassy body. Having said that, I never tested it and perhaps I am not as sensitive to the problem.

    However, since there is no way to accurately focus with an Alpa (unless you use GG), I was considering scale focusing with Disto and the HPF ring, but it seems like shimming is a prerequisite to that approach.

    Then again, I now realize shimming involves adjusting all the lenses that I have and that is a big turn-off. I don't think it's something I can do myself, and I certainly don't want to have to do that with all my future lenses.

    So... now I am back to not shimming and living with the error (hoping it's not too bad) and zone focusing.

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    Senior Member danlindberg's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    I suppose that zone focusing and hyperfocal technique will be ok without shimming the back or checking accuracy of the lenses. But I do not really see the point in choosing an Alpa with this approach in mind.
    Alpa is all about precision and peace of mind knowing everything works as intended.
    Now, hyperfocal works surprisingly well, but knowing "exact" distance via a distometre and dialing in this "exact" distance on the lens with HPF really is a joy. I have come so far in my trust in the system that I do not doublecheck anymore on the back. Focus is ALWAYS spot on. Fine, I am careful and slow tripodguy but at the end of the day I do not have any (maybe one in twenty!) images that are out of focus or in the wrong place. It just does not happen.
    So my advice is to have it shimmed to perfection and then use it with hyperfocal 80-90% of the time if you like, but those remaining images you want with perfect distance, then you can trust your equipment and the initial hazzle and money involved is worth everything.
    Alpa FPS • MAX • TC | Alpagon 32Hr | Helvetar 75 | Schneider 120N | Leaf Aptus II 5 • Leaf Credo 60 | www.danlindberg.com
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    Subscriber & Workshop Member GrahamWelland's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Quote Originally Posted by wgcho View Post
    However, since there is no way to accurately focus with an Alpa (unless you use GG), I was considering scale focusing with Disto and the HPF ring, but it seems like shimming is a prerequisite to that approach.

    Then again, I now realize shimming involves adjusting all the lenses that I have and that is a big turn-off. I don't think it's something I can do myself, and I certainly don't want to have to do that with all my future lenses.

    So... now I am back to not shimming and living with the error (hoping it's not too bad) and zone focusing.
    I'd just add that you can accurately focus the Alpa if you use a distometer. Very accurately in fact if your back is shimmed. I haven't used the GG for probably 18 months to be honest, particularly since I can review the image on the MFDB.

    As regards the lens adjustments, I'd just like to put that into perspective. My 90-HRW which I had adjusted was literally off by a mere fraction of a millimeter on the focus ring which meant that it just barely focused beyond infinity if I used the infinity hard stop. It was a lens I bought used but in mint condition but I have no idea what might have been adjusted or it's life after it left the factory and came to me. All other lenses were 100% spot on without exception.

    So I'll just echo what Dan, Thierry, Woody and I said regarding peace of mind and accuracy. Shimming will mean that you can absolutely trust where you set focus and if need be even just adjust to the infinity hard stop in many landscape situations and know that what you're shooting will be sharp. Razor sharp in fact.
    Remember: adventure before dementia!

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    Re: Do I really need shims for Alpa 12 V Adapter?

    There are a several tolerances that affect focus quality, not just the back or the body but the mount adapter, the lenses, and if you use HPF rings, then those as well.

    As for the back itself, sensor parallelism with the mounting surface can be an issue, but IMO, those sorts of issues are best solved by returning the back for service. I for one have not yet experienced this in any of the three backs I have owned.

    Another is the optical distance to the mounting plane. This can be caused to vary due to actual sensor location as well as the thickness and refractive index of the covering glass. I suspect that I have seen some difference in this regard between Phase and Leaf backs and it can be enough to upset critical focus. So with the Alpa, you might consider shimming the back depending on what you are shooting, but note that what is perfect for one back may not be perfect for another.

    The infinity point of the HPF rings offer another way of standardizing your focus point. Some systems, such as the arca helical, adjust the fore and aft distance adjustment by the computation experimentally of a focus offset. This takes into account both lens variation as well as back variation with the exception of parallelism of sensor to focus plane. The downside of this approach is that you need to compute the focus setting from the measured distance. Certainly this is not as convenient as rotating the hpf ring to a distance marked, but it is really just two numbers. A lens dependent constant divided by the distance then adding the offset. Some Arca owners have placed little tick marks on the lens mount to indicate a few common distances.

    No matter which system you use, critical focus needs to be determined and possibly adjusted.

    Warning though, it may not be the best thing to test wide open, as some lenses do have a bit of focus shift which seems most obvious in that first stop .
    Stopping down more than one though increases the DOF and makes the point of critical focus harder to judge.

    My personal recommendation would be to find critical focus wide open, then shoot another frame one stop down to see if the shift is appreciable with your specific lens. Often but not always, the increase in DOF will mask the shift should it exist.

    I am not saying which system is superior, just that some form of focus calibration is appropriate in any system you buy assuming that your desire is truly critical focus.
    -bob

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    Re: Do I really need shims for Alpa 12 V Adapter?

    you want to buy a top class camera, and at the same time you want to save 5% of the total amount, and not have your system totally adjusted... nonsense in my humble opinion...
    Yes 750 $ is expensive, but if money is a concern, then i'm not shure that a technical hight end camera is the way to go...

    but that's my two cents, not my 750 $ ;-)

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    Re: Do I really need shims for Alpa 12 V Adapter?

    Quote Originally Posted by archivue View Post
    you want to buy a top class camera, and at the same time you want to save 5% of the total amount, and not have your system totally adjusted... nonsense in my humble opinion...
    Yes 750 $ is expensive, but if money is a concern, then i'm not shure that a technical hight end camera is the way to go...

    but that's my two cents, not my 750 $ ;-)
    If he already had the shim-less adapter in-hand then by all means he ought to test it and see how it is. I do not know if he plans on using the hpf rings or not, but there is a bit of adjustability there too al long as it gets to a infinity (or beyond as they say)
    -bob

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    Re: Do I really need shims for Alpa 12 V Adapter?

    Try the shimless adapter and if you are not satisfied, return it for a shim adapter. Other companies can make high-end cameras that focus perfectly. I think you will find your Alpa able to do the same.

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    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Shashin,

    Again, it is not the Alpa camera the problem, see my post bellow. You will simply focus as precisely as the weakest element in your chain. In this case it is the position of the sensor, which has the same influence on final focus on any camera.

    Simply try it once and you will understand what is meant.

    Many have noticed the differences from one digital back to another, when upgrading for instance.

    Being able to shim is simply being able to get out the maximum sharpness out of your back.

    Best regards
    Thierry

    Quote Originally Posted by Shashin View Post
    Try the shimless adapter and if you are not satisfied, return it for a shim adapter. Other companies can make high-end cameras that focus perfectly. I think you will find your Alpa able to do the same.
    Thierry Hagenauer
    [email protected]

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    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    I would just like to repeat once again that it is not the camera which is the focus problem, but the back or the lens itself.
    If you don't notice it on your Hassy that doesn't mean that it doesn't exist. What seems to be sharp doesn't mean it's the maximum sharpness you can reach with a precisely adjusted sensor and/or lens. To see a difference it often needs a comparison side by side.

    best regards
    Thierry

    Quote Originally Posted by wgcho View Post
    Living in a different time zone (in Korea now), this is a great way to wake up - to find lots of useful information about the problem I'm dealing with. GetDPI rocks! Thanks for the all the comments~

    I'm still not sold on the idea that Digital Backs have more severe focusing issues. As Shashin pointed out, I never really had any problems using it with a Hassy body. Having said that, I never tested it and perhaps I am not as sensitive to the problem.

    However, since there is no way to accurately focus with an Alpa (unless you use GG), I was considering scale focusing with Disto and the HPF ring, but it seems like shimming is a prerequisite to that approach.

    Then again, I now realize shimming involves adjusting all the lenses that I have and that is a big turn-off. I don't think it's something I can do myself, and I certainly don't want to have to do that with all my future lenses.

    So... now I am back to not shimming and living with the error (hoping it's not too bad) and zone focusing.
    Thierry Hagenauer
    [email protected]

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    Re: Do I really need shims for Alpa 12 V Adapter?

    Quote Originally Posted by TH_Alpa View Post
    Shashin,

    Again, it is not the Alpa camera the problem, see my post bellow. You will simply focus as precisely as the weakest element in your chain. In this case it is the position of the sensor, which has the same influence on final focus on any camera.

    Simply try it once and you will understand what is meant.

    Many have noticed the differences from one digital back to another, when upgrading for instance.

    Being able to shim is simply being able to get out the maximum sharpness out of your back.

    Best regards
    Thierry
    Thierry, please show this. Say two landscape images shot at f/11 at half the hyper focal distance (the plane that will still have infinity in the DoF) with a difference of 0.01mm shim (you can use the Zeiss standard CoC of 1/1500 of the format diagonal for DoF). Describe how object distance was determined and where that plane is. If you say this makes a difference then it should be easy to show.

    BTW, how much will an Alpa body and lens mount expand from say -40F to 90F?

    Now, I have used reflex systems like Hasselblad, Mamiya, and Pentax. A reflex system will need tighter tolerances than an Alpa because the ground glass and mirror need to be in the right place or each will compound focusing errors. I look at my images and they are sharp. They are sharp where they are supposed to be sharp. A shim will just move that plane. Yet, in my images, I can see where the plane of focus is. You cannot get sharper than where the plane of focus is. Even with my sliding GG on my Linhof, no focusing error, so I am confused by your claims.

    BTW, my advice was just to order the adapter and determine if there was a problem--I assume not all backs have to be shimmed. I was not referring to the construction of the Alpa. You may be right that Phase, Leaf, and Hasselblad have really bad QC but on average they should get the sensor in the right place. Why assume there will be a problem? (I have seen the Optech video on shimming and they are really shimming the camera to a point closer than infinity--infinity is just not something that is far away.)

    But anyway, I would be happy to see some evidence. I really don't think hearsay is very helpful when your customers could be using targets that are not at infinity and then of course they will think the back would need to be shimmed.
    Last edited by Shashin; 7th April 2012 at 16:02.

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    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Shashin,

    I don't need to show anything, there are enough people here who experience this, also many who claimed like you that such "craziness" for precision is non-sense and who came back from that.

    Just have a look at the videos at Alpa's site, it shows and explains it perfectly.

    You look at your images and they are sharp: yes of course they are. But are you sure your sharpness plane is exactly at the exact place/distance you have set it on your scale?

    Shashin, you seem to purposely want to misunderstand and to distort what I am writing, 3 times now: I did say that it is not the camera which needs precision/adjustment, but the sensor/lens which do not necessarily have the same tolerances from one unit to the other (see some posts here and elsewhere from others).

    "you cannot get sharper than where the plane of focus is": obviously, yes of course. But it is the precision of this sharpness plane, thus the sharpness at the exact point (plane) where you want it which is important for some. This is what I considered as "maximum sharpness".

    "I assume not all backs have to be shimmed": obviously not, but much more than you would imagine, without speaking about lenses.

    "how much will an Alpa body and lens mount expand from say -40F to 90F?": that's another issue, and yes, you are perfectly right here, but not only an Alpa, ALL cameras/bodies/parts of the setup. This is something manufacturers will have to deal with sooner as you might think.

    I think it doesn't need to continue arguing. If you are happy with your results that's the most important. I have simply pointed out something which we daily have to deal with at Alpa, "Sensor position and planity/curvature".

    Best regards
    Thierry

    Quote Originally Posted by Shashin View Post
    Thierry, please show this. Say two landscape images shot at f/11 at half the hyper focal distance (the plane that will still have infinity in the DoF) with a difference of 0.01mm shim (you can use the Zeiss standard CoC of 1/1500 of the format diagonal for DoF). Describe how object distance was determined and where that plane is. If you say this makes a difference then it should be easy to show.

    BTW, how much will an Alpa body and lens mount expand from say -40F to 90F?

    Now, I have used reflex systems like Hasselblad, Mamiya, and Pentax. A reflex system will need tighter tolerances than an Alpa because the ground glass and mirror need to be in the right place or each will compound focusing errors. I look at my images and they are sharp. They are sharp where they are supposed to be sharp. A shim will just move that plane. Yet, in my images, I can see where the plane of focus is. You cannot get sharper than where the plane of focus is. Even with my sliding GG on my Linhof, no focusing error, so I am confused by your claims.

    BTW, my advice was just to order the adapter and determine if there was a problem--I assume not all backs have to be shimmed. I was not referring to the construction of the Alpa. You may be right that Phase, Leaf, and Hasselblad have really bad QC but on average they should get the sensor in the right place. Why assume there will be a problem? (I have seen the Optech video on shimming and they are really shimming the camera to a point closer than infinity--infinity is just not something that is far away.)

    But anyway, I would be happy to see some evidence. I really don't think hearsay is very helpful when your customers could be using targets that are not at infinity and then of course they will think the back would need to be shimmed.
    Last edited by Thierry; 8th April 2012 at 09:51.
    Thierry Hagenauer
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Quote Originally Posted by TH_Alpa View Post
    I would just like to repeat once again that it is not the camera which is the focus problem, but the back or the lens itself.

    Thierry
    that's a shame that there's no shimming system in the back itself... there is even registration difference between two backs from the same model... P45+ vs P45+ ... Aptus 22 vs Aptus 22...

    but, when used on a mamiya DF or similar, because of retrofocus wide angle, it doesn't affect performances as it does with technical cameras !

  25. #25
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Once again, thanks for all the great, insightful comments.

    Just to clarify, I will have the mount with shims, but I am contemplating returning for a shimless one.

    After reading all the comments, I am now much more worried than before. It seems like the shim kit alone is not the solution for accurate focusing. As commented before, I need to calibrate all my lenses, too. I believe this is not something I can do by myself, which means I need to send in all the lenses and have them calibrated together. If I purchase another lens (which is very likely), I need send it together with my back again. This sounds ridiculous to me. The DIY shim kit makes only sense to people with one lens??

    Some people say Alpa is for people who need precision. I actually object to that. It is the smallest wide angle solution for digital back with cropped sensor. Many people compare this to SWC as it is easy to carry around and shoot handhold. I actually think there are better/cheaper options for people who need precision. Or, am I missing something?

    -Ted

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    Re: Do I really need shims for Alpa 12 V Adapter?

    once you have the back set for one lens, your longest focal length, it is pretty easy to set the other lenses (this is not done by shimming; that part is over.) what you would do is make sure that when on the inf stop, each lens is in the best focus for a distant object. I was able to release the focus ring from the lens by loosening a screw or two, then you can rotate the barrel past the stop, checking focus by test shots. once inf is in focus, move the focus ring so the inf stop stops the barrel where it is, tighten the screws. pretty easy actually, best done tethered.

  27. #27
    Administrator Bob's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    No need to send your lenses anywhere. It is not hard to adjust them if necessary.
    -bob

  28. #28
    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Ted,

    You don't have to worry about this, you don't necessarily need to calibrate your lenses, rather not. Just do some test shots with one of your lenses with a longer FL of e.g. 90 mm or longer. Check your back as per the video on the Alpa side and shim it accordingly IF needed. It takes may be an hour to do this, then you are sure that your sensor is at the right distance.
    Then take your other lenses with the same back and check your focus on these lenses. If you are noticing that your infinity point is not in focus, then it needs the lens to be corrected, if you are able to do it yourself (which isn't that difficult at all) or sent to the factory for calibration (if you don't feel secure enough), not the back again. But there is a big "chance" that the focus corresponds for these other lenses too.

    Best regards
    Thierry

    Quote Originally Posted by wgcho View Post
    Once again, thanks for all the great, insightful comments.

    Just to clarify, I will have the mount with shims, but I am contemplating returning for a shimless one.

    After reading all the comments, I am now much more worried than before. It seems like the shim kit alone is not the solution for accurate focusing. As commented before, I need to calibrate all my lenses, too. I believe this is not something I can do by myself, which means I need to send in all the lenses and have them calibrated together. If I purchase another lens (which is very likely), I need send it together with my back again. This sounds ridiculous to me. The DIY shim kit makes only sense to people with one lens??

    Some people say Alpa is for people who need precision. I actually object to that. It is the smallest wide angle solution for digital back with cropped sensor. Many people compare this to SWC as it is easy to carry around and shoot handhold. I actually think there are better/cheaper options for people who need precision. Or, am I missing something?

    -Ted
    Last edited by Thierry; 8th April 2012 at 09:01.
    Thierry Hagenauer
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  29. #29
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Wow, I didn't know I could calibrate the lens myself. Thanks for the clarification!

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    Re: Do I really need shims for Alpa 12 V Adapter?

    i found my 43 Sk was off by about 2mm movement on the ring, the 70R was right on.
    Thierry: are you not seeing my posts? it seems you are repeating what I already said an hour earlier

  31. #31
    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    I've seen your posts, yes. However I think that it doesn't harm to get the opinion of several members, even if the same. Does it?

    Best regards
    Thierry

    Quote Originally Posted by jlm View Post
    i found my 43 Sk was off by about 2mm movement on the ring, the 70R was right on.
    Thierry: are you not seeing my posts? it seems you are repeating what I already said an hour earlier
    Thierry Hagenauer
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  32. #32
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Quote Originally Posted by TH_Alpa View Post
    I don't need to show anything, there are enough people here who experience this, also many who claimed like you that such "craziness" for precision is non-sense and who came back from that.
    So, no proof, just hearsay and marketing. Well, Thierry, I am allowed to join conversations like this. My comments are for the OP. There is no need for you to involve yourself with what I write.

  33. #33
    Senior Member Thierry's Avatar
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    Re: Do I really need shims for Alpa 12 V Adapter?

    Shashin,

    Please, why do you make it a confrontation when it comes to help somebody and clarify things?
    With all due respect, I shall intervene whenever I see something wrong or misleading being written, and there has been some.

    And why do you need to denigrate a company with words like the ones you are using? I don't understand your agenda very well. I have been around for quite some years and have a record of somebody being honest, which you put in doubt with your words.

    We can disagree, but there are ways to say it.

    There are actually proofs, for those who want to see and understand the issue, and they have been published since years, here and elsewhere.

    I invite you to visit us at Alpa in Zürich, then we will show you what is meant.

    Best regards
    Thierry

    Quote Originally Posted by Shashin View Post
    So, no proof, just hearsay and marketing. Well, Thierry, I am allowed to join conversations like this. My comments are for the OP. There is no need for you to involve yourself with what I write.
    Thierry Hagenauer
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