Lens calibration - send the body too?

My worry if I ever have to calibrate a lens that I'd have to send all my lenses and the body off. It'd annoy the hell out of me to have to send another lens back and then another, or even worse the first again!
 
Vertigo1 said:
A slight difference would be understandable, but a range of 9 isn't in my opinion. A lens, especially one that expensive, should focus properly at all focal lengths. When the adjustment range for "perfect" focus is that wide, I'd content that it doesn't meet that criteria.
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Yeah 9 is to much and you should send it in if it is affecting your images, you should just bereaved when it comes back that it still has a difference of 3-4 etc.

3rd party lenses tend to be a bit worse at the non-uniformity, and obviously bigger zoom ranges tend to be worse than th 2-3x of pro lenses.
 
A range of 3-4 would be perfectly acceptable - I'm not expecting it to be calibrated to the point where the subsequently required micro-adjustment is identical at all focal lengths - that's not reasonable.
 
There are no priority form, just 1 form.

When you signed up to CPS you should have got some bright green stickers, stick one of those on the parcel and it'll stand out from the rest. State on the covering letter that you are a Gold/Platnium level member etc and put in your membership number.
 
Interesting - the form you download from the CPS site has the CPS logo at the top and the title "Equipment for Priority Repair".

I know the stickers of which you speak - whether I can actually find them again is another matter! :D
 
Yes I have - works well.

It's nothing you can't do manually but it just automates the process for you. As it uses a predefined algorithm to compare the sharpness of shots, it's also a little more deterministic than just using your own judgement about whether one shot is sharper than another or not. That said, the results do seem to vary a little on repeated runs but only by one point on the adjustment scale - to be expected I guess as the difference between two adjacent points on the scale is miniscule.

Be aware that, on the 5D3, Canon's API doesn't currently allow the software to set the adjustment value so instead it directs you to change it to a specific value after each test shot, which is a lot more tedious than the fully automatic mode.
 
Is it usual to get any kind of confirmation email from Canon acknowledging receipt, or not hear anything unless they actually need to contact you?

Just wondering as it was delivered to them yesterday but not heard anything.
 
They get itine day, if not CPS (no sticker) then they log it later on in the day, normally get an email acknowedge receipt next day. You can always call and ask.
 
Yeah it had the lurid green CPS sticker on it. Will call them tomorrow and check they've got it ok.

Of course my CPS level only gives me a five day turnaround compared to your two so it might be a little further down the queue :)
 
Well, despite all the glowing reports about Canon Elstree, I'm thoroughly unimpressed with them so far!

Zero communication. No acknowledgement of receipt or anything else. Had to call them last week just to confirm they'd actually received it ok.

CPS turnaround time should be five working days, which is today, yet I have no idea what's happening, when I'll get it back or whether they've even looked at it.

Going to have to call them again to chase.
 
I spoke to them yesterday - apparently the reason I'd heard nothing was that they were emailing me but someone had entered my address incorrectly into their system - doh.

Got a call from a technician this morning saying he was looking at it and wanted to clarify the exact issue and what body I used it on mainly. Got notification towards the end of the day that it was being despatched back to me so hopefully will get it back tomorrow or Friday :)
 
Well it's back! Won't have a chance to actually use/test it for a few days so don't yet know exactly what they've done to it but I'm just relieved to have it back in my possession :)
 
V F said:
Do many of you use something like this? http://www.squit.co.uk/photo/files/FocusChart.pdf
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Yes, just make sure to really follow the instructions and take a very methodical approach combined with real world testing. Also be aware that different focal points can have different errors, some lens have a strong field curvature such that the outerw edges are at a different focal length compared to the center. Using live view to verify focus vs other issues is handy.

One thing to be careful of is that you will get a different focus distance if you go from close to far vs far to close focus. Test both ways and find a middle ground.
Be very careful to get things aligned as well, a few degrees error in rotation can res,t kana visible focus issue that is not a real focus problem.
 
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