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    Micro adjust woes

    I have to admit I have been struggling with my combo of the 1Dmkiv and the sigma 150.600 sport ,soon after purchase I did my usual micro adjust and as most will know I have been getting some superb close up shots with it ,BUT I haven’t been totally happy with mid to long range shots that require a degree of cropping .so this morning I bit the bullet and did a mid/long range MA using the roof of a house opposite as my target ,ridge tiles on the corner sloping at a 45degree angle .totally different result ,I have now had to dial in minus 5 to achieve a sharp shot and it might need more yet .
    Sunday’s hen harrier shots were the deciding factor as last night I came very close to e.baying the whole lot .hopefully this will work better
    to illustrate I have added some pics below as direct uploads first off the roof used for m.a at 36.5 mtrs lens set at zero, next with it adjusted to minus 5 and finally a number plate on a car over the road distance 71.2 mtrs away this shot was testing under working conditions so hand held ,I think the resolving power says it all, on my version of the number plate I can clearly read the middle row of lettering
    Attached Files
    Last edited by the black fox; 24-10-2017, 15:13.

    #2
    Re: Micro adjust woes

    I am still baffled why we should have to do this . This gear we are using is by no means cheap , and seems at times we will struggle to get a sharp photo using stuff straight from the box . Sorry for the rant , but it`s bloody annoying , how are we supposed to have faith in our gear ? Can definitely see the improvement on the roof tiles Jeff .

    Comment


      #3
      Re: Micro adjust woes

      As with any product, you will get manufacturing tolerances. Individual components can all be within tolerance and acceptable for final assembly, but if you get critical components where one may be towards to the top of tolerance and another towards the bottom, the final assembly can be less than optimum. Even with Computer Aided Manufacturing, these tolerances can be the difference between a sharp machine tool and one that has been used on a number of components, or cold cutting fluid against hot cutting fluid. The tolerances we are talking about are much less than a human hair, we are talking microns, where 5 microns equals 1/100mm.

      Normally this wouldn't cause us much of a problem, as these tolerances are so fine and stopping down the lens by at least one stop should provide enough extra depth of field to cover this. However, there are areas of photography such as wildlife and sport where long lenses are used and the inaccuracies are magnified according to the length of the lens. Coupled to that, these areas of photography are often fighting against the light to obtain suitable settings for the subject and consequently, the lens is often used wide open. The ability to micro adjust globally if the problem is with the body, or to each individual lens if it is a specific lens is very welcome and saves sending a body/lens combination to Canon for adjustment. We all get used to our equipment, find the sweet spot and try to work within that and micro adjustment is a very useful tool to ensure that you can fine tune your gear for maximum sharpness.

      Jeff's 150 - 600mm Sigma is a third party telephoto zoom of 4x magnification. It is more likely to need some micro adjust than say a Canon 600mm L series prime lens. With a 4x zoom, it is unlikely to hold perfect sharpness throughout the full zoom range, but with micro adjust, Jeff can zero in on the magnification that he predominantly uses, presumably more towards the 600mm than the 150mm.

      It is difficult to do your best work if you are doubting your equipment, but with a solid tripod, an appropriate target and an hour to spare, you can be confident that you kit is working well and I am all in favour of that. Much as I trust Canon to supply me with top quality kit, I am far more comfortable when I have proved it.
      Colin

      Comment


        #4
        Re: Micro adjust woes

        Agree with everything Colin says. If you actually look at how autofocus works, sometimes I think it's a miracle how accurate it is, usually. For example, with a 600 mm lens on the iD4 at 10 metres the depth of field is only about 10 cms so any slight error is really noticeable. The same is true for portrait photographers shooting at F1.2 or F1.4 for that "razor thin" depth of field.

        It's also easy to always blame the lens when the camera is just as likely to be at fault, but you only notice at these extremes, not when using more "normal" lenses and settings. A zoom lens is always likely to have more problems, there are so many component lenses inside that have to move around, both when focussing and when zooming, a minute fraction of a millimetre out can cause issues. Of course, with the Sigma dock you can set and store up to 16 different corrections for a zoom lens, 4 different focal length and subject distance combinations, something you can't do with Canon.

        Of course, proponents of mirrorless systems over DSLR will point out that a/f is always spot on with those, one reason for the profusion of pro photographers switching to Sony full frame mirrorless, Sony being far ahead of Canon and Nikon in that area

        I was reading that while NASA use apparently "standard" lenses (Nikon) that we could buy off the shelf for their space work they pay to have their lenses very accurately adjusted and set, but they pay $100,000 for a lens that would cost $2,000 in a shop. That's to cover the many hours of time spent testing, adjusting, retesting, again and again to get everything perfect, zero tolerance, not really practical for the price we pay.

        Being a bit geeky sometimes, I really enjoy reading Lens Rentals Blog, those guys rent out thousands of lenses and bodies every week and really know their stuff. Every so often they take a lens apart to see how it's put together and when you see how many parts there are, and consider they all have to be positioned and aligned down to thousandths of a millimetre, suddenly lenses don't seem as expensive as they used to. Try this look at the 100 - 400 mm IS L Mk II for example, which they consider perhaps the "best built lens ever", a masterpiece of precision engineering.
        EOS 6D, 6D Mk II, 80D, 70D, 100D, 200D, M50, M100. Canon 10-18, 18 - 55, 55 - 250 IS STM lenses, Canon 16 - 35 mm F4L, 35 mm EF-S macro, 50 mm F1.8 STM, 60 mm EF-S macro, MPE-65 macro, 85 mm F1.8, 200 mm F2.8 L II, M 15 - 45 mm, M 22mm F2, M 32mm F1.4. Sigma 24 - 35 F2 Art, 135 mm F1.8 Art, 17 - 50 F2.8 DC, 105 mm OS macro, 100 - 400 C, 150 - 600 C.

        Comment


          #5
          Re: Micro adjust woes

          I don't wish to tread on anyone's toes but I believe in the axiom "if it ain't broke don't fix it"! I prefer to use Canon lenses and apart from my Kenko 1.4 HD TC, all are Canon ones. I am quite happy with the results I get, which are all within my capabilities. Recently I took photos of two difficult objects using my Canon lenses- one was a brass plaque and the other was grave headstone which came to light as a result of excavations taking place at my cathedral-St.Asaph. I attach these photos for you to see.

          IMG_6825 by Nathaniel Ramanaden, on Flickr

          St.Asaph Cathedral for LM (2) 27th Aug 2015 017 by Nathaniel Ramanaden, on Flickr
          Last edited by Nathaniel; 27-10-2017, 11:15.
          Canon 6D; Canon 760D;Canon G15;Canon 40mm f2.8(Pancake);Canon 50mm f1.8(ii); Canon 17mm-40mm f4L;Canon EF-S 10-18mm f4.5-5.6 IS STM;Canon EF-S 55-250mm f4-5.6 STM lens;Canon 24mm-105mmf4L IS;Canon 70-300mm f4-f5.6 L IS USM;Kenko 1.4x HD TC;Canon 430EX ii flash;Giottos tripod;Manfretto monopod;Cokin P filters + bits and pieces!

          www.flickr.com/photos/nathaniel3390

          North Wales where music and the sea give a great concert!

          Comment


            #6
            Re: Micro adjust woes

            Cheers Colin and Richard for explaining far better than I ever could ,yes there is definetly a difference in sharpness
            ARE YOU READY TO SPIT YOUR COFFEE OUT LADS


            ,if you take a look at today’s hen harrier shots you will see though that’s there’s hardly any if any at all improvements though , that’s because mr numpty here forgot to set the alterations to the camera ,which I didn’t realise till very late on today .
            Ah well there’s always another day
            Last edited by the black fox; 27-10-2017, 21:00.

            Comment


              #7
              Re: Micro adjust woes

              Does this need to be done in very good light conditions , and what distance would you set it for using a prime ? Assuming you would need to make these adjustments with any T.C`s fitted as well ? Does it matter what we use to focus on , is Jeffs tiled roof as good example as any ? I wish someone who knew what they were doing lived close by to give me some lessons

              Comment


                #8
                Re: Micro adjust woes

                It’s easy mark ,I used the roof tiles to get a adjustment at the rough distance I want to shoot at I.e for the owls ,you need to put your camera into 1shot ,set your aperture wide open ,lock it onto target so there no movement and take 3 or 4 test shots .take card out and check on computer any backward or forward adjustments will be easily seen as in my examples of the roof tiles .in your case do it twice once with the lens and again with t.c added .

                Don’t forget to set it to the camera once done !!

                as a matter of interest the card type micro adjust system set the angle at roughly the same angle as a pitched roof ,hence my use of them if you can get eye level with one to i.e a upstairs window it might make it even more accurate
                Last edited by the black fox; 28-10-2017, 11:54.

                Comment


                  #9
                  Re: Micro adjust woes

                  Thanks Jeff , will try and find time to look into it properly .

                  Comment


                    #10
                    Re: Micro adjust woes

                    Don't run away with the idea that Canon lenses won't need micro focus adjustment. Manufacturing tolerances apply to them as well and I have had two Canon lenses that required micro adjustment, equally I have had third party lenses that haven't further i have lenses that are perfect on one body and require adjustment on another. This is why Canon have included the facility as they are aware that manufacturing tolerances of both lenses and cameras can cause minute adjustments necessary. BTW other manufacturers are similarly affected.
                    Alan

                    No longer using Canon but still teaching new Canon users (and others) the gentle art of Photography.

                    http://www.springfield-photography.com/

                    Comment


                      #11
                      Re: Micro adjust woes

                      sshhhhh don't tell nat

                      Comment


                        #12
                        Re: Micro adjust woes

                        I only wish there was some fail safe easy way of doing it .

                        Comment


                          #13
                          Re: Micro adjust woes

                          Mark do you want me to send you my phone number again ?
                          It really is a easy job and if you mess it up just re.set to zero and try again

                          Comment


                            #14
                            Re: Micro adjust woes

                            I am ok for now Jeff , I have logged your number on my phone , so no worries . And thank you very much , I may well take you up on it one day . Cheers mate .

                            Comment


                              #15
                              Re: Micro adjust woes

                              A couple of years ago I made my own target to help me carry out this task and it has helped greatly. I have since come across a website that describes how to do the job. https://petapixel.com/2013/03/12/ghettoca-a-diy-lens-calibration-tool-for-micro-adjustment-enabled-dslrs/
                              Alan

                              No longer using Canon but still teaching new Canon users (and others) the gentle art of Photography.

                              http://www.springfield-photography.com/

                              Comment

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