Camera / lens callibration, help and advice please

[Mark von Kanel]

A while back i invested in an FX camera body and good glass. To tell the truth ive been a little disappointed sometimes with the results, i was putting it down to technique but my technique was fine with my DX, which had the same pixel density as my FX (d7000 d800) and even using a tripod it somehow seemed off.

I read on here a throw away comment about peeps worrying about inconsequential stuff when they hadnt bothered to calibrate their monitors or lens/ camera combinations.

That got me to thinking, i read this article:

http://photographylife.com/how-to-qu...tofocus-issues

It seems well thought out and quite lodgical so i tested my D800 and 70/200 f2.8 combo in the manner that the article recommends and got the following results.

Image taken live view contrast detect



Image taken normal view phase detect



Calibrated image with normal phase detect. Problem solved!



Theres quite a bit of difference! so im thinking i need to calibrate..... ive found the following software:

http://www.reikan.co.uk/focalweb/

and theres a gizmo called lens align

SO here are my questions.

is the test procedure i carried out from the article relevant and correct?
is there a better more accurate way of doing this?
What methods of calibration are you using?
Is the focal software any good, is it worth the extra money for pro version? or am i better off with lens align. is there a way of doing this without spending yet more money?
How often or even should i bother calibrating?

Thanks all.

[Stagecoach]

Mark,

Where are you taking your test shots? If onboard are the generators running?

Grahame

[Mark von Kanel]

Hi Grahame

Yes im on board and yes the gens are running but there is no vibration, we are at anchor and the ship is to big for generator resonance to be an issue. also the results differ depending on which lens i test.

My 105 macro shows virtually no problems my 24/70 has slight issuses but nowhere near as pronounced.

if it were vibration related wouldnt the problem sow on both test images?

[george013]

You will to have the lens finetuned. You don't need software for that. You can do it yourself using liveview.
George

[Shadowman]

I would assume you did the test shots with camera tripod mounted, is that the same support used for the shots giving you issues?

[george013]

Maybe this will help. https://www.youtube.com/watch?v=7zE50jCUPhM
George

[Stagecoach]

Hi Grahame

Yes im on board and yes the gens are running but there is no vibration, we are at anchor and the ship is to big for generator resonance to be an issue. also the results differ depending on which lens i test.

My 105 macro shows virtually no problems my 24/70 has slight issuses but nowhere near as pronounced.

if it were vibration related wouldnt the problem sow on both test images?

Hi Mark,

Just thought I would mention the vibration as the buckets I used to be on certainly suffered

Sounds like you are going in the right direction but from my experience I have read so many 'fine tune' threads since the function was fitted on some DSLRs it soon became obvious that many did not take account of repeatability and hysteresis before attempting adjustments and many of the early articles never made this point.

But you will be aware of those due to your job.

Grahame

[Mark von Kanel]

Hi Mark,

Just thought I would mention the vibration as the buckets I used to be on certainly suffered

Sounds like you are going in the right direction but from my experience I have read so many 'fine tune' threads since the function was fitted on some DSLRs it soon became obvious that many did not take account of repeatability and hysteresis before attempting adjustments and many of the early articles never made this point.

But you will be aware of those due to your job.

Grahame

This is why im asking for real world advice! do you calibrate?

[Mark von Kanel]

I would assume you did the test shots with camera tripod mounted, is that the same support used for the shots giving you issues?

hi John,

yes all shots were taken under the same conditions, within minutes of each other.

[Colin Southern]

This is why im asking for real world advice! do you calibrate?

I don't - never had the need. But then again, I shoot Canon

(*** grabs a life preserver - inflates water wings - and jumps overboard! ***)

[Mark von Kanel]

Maybe this will help. https://www.youtube.com/watch?v=7zE50jCUPhM
George

Thanks George ill look at the vid, im a bit confused how to do it with live view but im sure the vid will make it all sparkly clear!

[Mark von Kanel]

I don't - never had the need. But then again, I shoot Canon

(*** grabs a life preserver - inflates water wings - and jumps overboard! ***)

TSK! what kind of real man are you? a chance to pixel peep and photograph test charts and you dont want to do it??? go on admit it, your itching to print that test target and show us your pixels .

Hope the weight of your L series pulls you under... Mind you we'll be able to find you quite easily with that daft white lens...

[ST1]

Maybe this will help. https://www.youtube.com/watch?v=7zE50jCUPhM
George

Mark
I have used this Dot Tune method to check and adjust all of my lenses, it worked for me. If you do try it dont forget to turn off your lens/camara IS/VR before commencing the testing. My 5D3 body allows you to tune and save the AFMA for each end of a zoom lens.
Prior to using the DotTune method I did try Auto Focus Micro Adjustments (AFMA) using this target (see link below) arrangement and found it to be a far more labour intensive method, but I did enjpoy the Blue Peter element of printing and making the target.
Target LINK

[Shadowman]

hi John,

yes all shots were taken under the same conditions, within minutes of each other.

Mark,

Going back to your original questions:
1. Is the test method relevant and correct? It showed a drastic difference between your focusing modes (contrast aand phase) with phase not able to correctly focus on the patterns, so I would say the test method was somewhat relevant. Is the test method correct? The method utilizes a focus area that almost all cameras have difficulty correctly focusing on, but how often would you encounter such a pattern? If you get the same focusing inconsistencies with every scene, then you've definitely got issues with your system; the final outcome depends on if it's the lens or the camera.

I've tried similar tests but have never had my system recalibrated, I tend to alter my shooting style if I believe I have a focusing problem, for me my focusing issues are typically camera shake and subject movement. I typically shoot handheld, my tripod mounted shots usually come out fine.

[chauncey]

Mark, I shoot Canon and I have calibrated all my lenses...they all require different numbers to adjust
for back/front focusing.
I simply set up a small mirror to adjust tripod/camera position to the point that you're shooting a
reflection of your lens>tape the target onto the mirror>fiddle with the camera's custom function
software until proper focus is achieved. I've discovered that I must disable my lens vibration
reduction settings, when possible, if I'm using a heavy duty tripod.

[ajohnw]

There is a much better way of checking lens focus than these targets, Described here

http://www.northlight-images.co.uk/a...djustment.html

As with any such test squaring up the camera to the target is very important if results are going to be looked at rather critically. This test will even show signs of slight miss alignment. The bulls eye patterns change.

As pointed out when finally checking the AF you need to use it from in front of the target and also from behind. No adjustments for that aspect are available as far as I know.

John
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[Mark von Kanel]

Mark
I have used this Dot Tune method to check and adjust all of my lenses, it worked for me. If you do try it dont forget to turn off your lens/camara IS/VR before commencing the testing. My 5D3 body allows you to tune and save the AFMA for each end of a zoom lens.
Prior to using the DotTune method I did try Auto Focus Micro Adjustments (AFMA) using this target (see link below) arrangement and found it to be a far more labour intensive method, but I did enjpoy the Blue Peter element of printing and making the target.
Target LINK

Hi Peter,

Ive just used the dot tune method and it was spot on... or dot on even!! i even took photos a couple of increments either side to compare and the dot tune was on the money, unfortunately canon are ahead in this area as well as many others with nikon ( nikon if your reading 1 stop bracketing???? Please!!!) nikon only allow one adjustment per lens so i set it in the middle. heres the shot at +2



problem solved!

[Shadowman]

I would also like to view the images that created this query, perhaps there is something that would provide more helpful clues.

[Mark von Kanel]

I would also like to view the images that created this query, perhaps there is something that would provide more helpful clues.

John, your actually suggesting i take some images of stuff other than a test target???? Wash your fingers off with soap! how dare you type such blasphemy? ill see what i can find john but my catalog is at home not on my lappy.

whilst im at work im pretty much spending my time studying (and shooting test targets) which is why most of my current posts are technical or pp related.... i do have some from an envioromental portrait session that i shot before i came to work. ill have a look and see what ive got.

[ajohnw]

John, your actually suggesting i take some images of stuff other than a test target???? Wash your fingers off with soap! how dare you type such blasphemy? ill see what i can find john but my catalog is at home not on my lappy.

whilst im at work im pretty much spending my time studying (and shooting test targets) which is why most of my current posts are technical or pp related.... i do have some from an envioromental portrait session that i shot before i came to work. ill have a look and see what ive got.

The link I posted provides a target that is just displayed on a PC screen. For telephoto testing some use a laptop because just like many things including the sort of test targets you have posted distance comes into it - more so with those actually whe they are used for their intended purpose. The target in the link isn't terribly sensitive to that aspect.

John
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