Comments on: review: LensAlign focus calibration system http://neilvn.com/tangents/2009/05/06/review-lensalign/ photography by Neil van Niekerk Wed, 10 Mar 2010 04:06:32 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: Carlos Espinoza http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2970 Carlos Espinoza Mon, 04 Jan 2010 17:26:08 +0000 http://www.planetneil.com/tangents/?p=964#comment-2970 One clarification to my previous post: As you increase your camera/subject distance, the DOF area recedes. So, if your lens suffers from a slight front focusing problem at 10 feet for example, instead of messing around with AF Fine tuning you better stop down so, when you shoot beyond 10 feet, the DOF will fall where it belongs. On the contrary, if your lens has even a slight back focusing problem, you better adjust the AF fine tuning setting. That is because as you increase the camera/subject distance your DOF will move even further away from you and you will end up with worthless pictures. One clarification to my previous post:

As you increase your camera/subject distance, the DOF area recedes. So, if your lens suffers from a slight front focusing problem at 10 feet for example, instead of messing around with AF Fine tuning you better stop down so, when you shoot beyond 10 feet, the DOF will fall where it belongs.

On the contrary, if your lens has even a slight back focusing problem, you better adjust the AF fine tuning setting. That is because as you increase the camera/subject distance your DOF will move even further away from you and you will end up with worthless pictures.

]]> By: Carlos Espinoza http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2969 Carlos Espinoza Mon, 04 Jan 2010 16:37:49 +0000 http://www.planetneil.com/tangents/?p=964#comment-2969 Neil: Thanks for your informative article. There is one thing in it that wasn't explained though. The AF fine tuning settings you choose will only be good for a particular distance/aperture combination. If you typically shoot at fairly the same distances and apertures, your adjustment will work fine and will render sharp pictures. However, if you are a generalist, (i.e., the type of guy who photographs under different subjects/distances/apertures situations), you must be aware that one single setting will not be good to cover all these situations. For example, if your take a picture at 10 feet with a 300mm F/4 and you came up with a AF fine tuning setting of +12, you will not get you sharp pics if you photograph a subject located at 30 feet using the same AF Fine Tuning setting. In summary and based on my tests, I believe now that one should use AF Fine Tuning only when there is an abnormal (excessive) front or back focus situation. Neil:

Thanks for your informative article. There is one thing in it that wasn’t explained though. The AF fine tuning settings you choose will only be good for a particular distance/aperture combination. If you typically shoot at fairly the same distances and apertures, your adjustment will work fine and will render sharp pictures. However, if you are a generalist, (i.e., the type of guy who photographs under different subjects/distances/apertures situations), you must be aware that one single setting will not be good to cover all these situations. For example, if your take a picture at 10 feet with a 300mm F/4 and you came up with a AF fine tuning setting of +12, you will not get you sharp pics if you photograph a subject located at 30 feet using the same AF Fine Tuning setting.

In summary and based on my tests, I believe now that one should use AF Fine Tuning only when there is an abnormal (excessive) front or back focus situation.

]]> By: Ed Wilson http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2962 Ed Wilson Fri, 14 Aug 2009 17:26:08 +0000 http://www.planetneil.com/tangents/?p=964#comment-2962 Neil... I am taking the plunge on the LenAlign... I have had nothing but grief from my zoom lenses ( sigma and nikon ). The problem is so bad that I have been using my legacy primes dating back to 1974 in order to get satisfactory sharpness. Trouble is my eyes are old too. Still, I'm getting far better results with old AI glass... not supposed to happen. OTOH I am very happy with the sharpness of my 60mm Micro Nikkor and a 24-60 2.8 Sigma... everything else is mush.. The lens align will either solve the problem, or lead to determining if I need a new lensmount on the camera body.. or just a new camera.. Neil… I am taking the plunge on the LenAlign… I have had nothing but
grief from my zoom lenses ( sigma and nikon ). The problem is so bad that
I have been using my legacy primes dating back to 1974 in order to get satisfactory
sharpness. Trouble is my eyes are old too. Still, I’m getting far better results with old AI glass… not supposed to happen. OTOH I am very happy with the sharpness of my 60mm Micro Nikkor and a 24-60 2.8 Sigma… everything else is mush.. The lens align will either solve the problem, or lead to determining if I need a new lensmount on the camera body.. or just a new camera..

]]> By: Curtis Copeland http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2968 Curtis Copeland Wed, 15 Jul 2009 19:03:08 +0000 http://www.planetneil.com/tangents/?p=964#comment-2968 Great information. I was just noticing some focusing issues with my 5D MKII. Thanks for the insight! Great information. I was just noticing some focusing issues with my 5D MKII. Thanks for the insight!

]]> By: Neil http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2967 Neil Fri, 26 Jun 2009 08:17:40 +0000 http://www.planetneil.com/tangents/?p=964#comment-2967 <blockquote>Just an update. I've used this Nikon 200mm f2 a lot again at a few shoots recently, and I am really happy with how sharp it is now. No issues with back-focusing. But I did work within a close range for these tight portraits, and not anywhere near infinity. Neil vN</blockquote> <img src="http://www.planetneil.com/tangents/images/models/sasha-l/SashaL-124.jpg">

Just an update.

I’ve used this Nikon 200mm f2 a lot again at a few shoots recently, and I am really happy with how sharp it is now. No issues with back-focusing. But I did work within a close range for these tight portraits, and not anywhere near infinity.

Neil vN

]]> By: Ed Wilson http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2966 Ed Wilson Wed, 17 Jun 2009 21:37:55 +0000 http://www.planetneil.com/tangents/?p=964#comment-2966 Neil! Thanks for this... My D-300 is so bad that I've abandoned all my AF lenses for the moment. The last three shoots I've done with vintage Manual focus lenses. I've thought about using the adjustment utility but the one time I tried, I quickly realized without an objective measuring device, I'd just be guessing at which way to go. Hopping over to the LensAlign site to further enrich them... Thnx Neil!

Thanks for this… My D-300 is so bad that I’ve abandoned all my AF lenses for the moment. The last three shoots I’ve done with vintage
Manual focus lenses. I’ve thought about using the adjustment utility but the one time I tried, I quickly realized without an objective measuring device, I’d just be guessing at which way to go. Hopping over to the LensAlign site to further enrich them… Thnx

]]> By: Tim Schooler http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2965 Tim Schooler Wed, 03 Jun 2009 17:30:05 +0000 http://www.planetneil.com/tangents/?p=964#comment-2965 Hey Neil, thanks so much for the reply. I am thinking about sending it in, but the 70-200 is flawless on my D3 so I hate to have them adjust it for the D3x since I suspect that may affect its performance on the D3. Hey Neil, thanks so much for the reply. I am thinking about sending it in, but the 70-200 is flawless on my D3 so I hate to have them adjust it for the D3x since I suspect that may affect its performance on the D3.

]]> By: Neil http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2964 Neil Wed, 03 Jun 2009 07:54:43 +0000 http://www.planetneil.com/tangents/?p=964#comment-2964 <blockquote>Tim, I haven't done such a thorough test on my 70-200 .. but I am very happy with that lens. But you're right, there isn't a way for a user to adjust or finesse a lens' focusing performance like that. Perhaps it needs a trip to Nikon Service Center. Neil vN</blockquote>

Tim, I haven’t done such a thorough test on my 70-200 .. but I am very happy with that lens.

But you’re right, there isn’t a way for a user to adjust or finesse a lens’ focusing performance like that. Perhaps it needs a trip to Nikon Service Center.

Neil vN

]]> By: Tim Schooler http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2963 Tim Schooler Wed, 03 Jun 2009 07:01:08 +0000 http://www.planetneil.com/tangents/?p=964#comment-2963 Hi Neil, have you tried testing any of your zooms? I have found a focusing error on my 70-200 when used on my D3x, but the 70-200 is perfect on my D3. I used Lens Align Pro and found the 70-200 was front focusing but only at 135 and 150mm focal lengths. At 200mm and all other focal lengths it is perfect. I don't see any way to micro fine tune for different focal lengths on the same lens. Just curious as to whether you have found the same thing in testing zooms, or whether you have tried it? Regards, Tim Hi Neil, have you tried testing any of your zooms? I have found a focusing error on my 70-200 when used on my D3x, but the 70-200 is perfect on my D3. I used Lens Align Pro and found the 70-200 was front focusing but only at 135 and 150mm focal lengths. At 200mm and all other focal lengths it is perfect. I don’t see any way to micro fine tune for different focal lengths on the same lens. Just curious as to whether you have found the same thing in testing zooms, or whether you have tried it?

Regards,

Tim

]]> By: Neil http://neilvn.com/tangents/2009/05/06/review-lensalign/#comment-2961 Neil Wed, 27 May 2009 07:51:56 +0000 http://www.planetneil.com/tangents/?p=964#comment-2961 <blockquote>Ron, though I haven't specifically made any tests to see if there are variations with distance - I fear you might be correct - that the focus error differs with the distance that you're using the lens at. It's something I have to still investigate. In adjusting this lens, I am happy that it is now correct for what would be the majority range that I work in when photographing portraits. I've seen recommendations that ideally the lens alignment should be done at 50x the focal length. But then I can't discern the detail necessary to make the adjustments. Even at 25x it's a bit of a push. best Neil vN</blockquote>

Ron, though I haven’t specifically made any tests to see if there are variations with distance – I fear you might be correct – that the focus error differs with the distance that you’re using the lens at. It’s something I have to still investigate.

In adjusting this lens, I am happy that it is now correct for what would be the majority range that I work in when photographing portraits.

I’ve seen recommendations that ideally the lens alignment should be done at 50x the focal length. But then I can’t discern the detail necessary to make the adjustments. Even at 25x it’s a bit of a push.

best

Neil vN

]]>