Originally Posted by neuroanatomist
I don't mean to complain, and I'm sure the Canon guys have their reasons... but I wonder why the heck they don't just make it view 1-1? I mean, the whole point of 10x is to judge sharpness. Why not design it so it does that as well as possible?
A touch of OCD? The 5DII would have to say 8.775x instead of a nice round 10x....
Several times in this string, I saw the word tedious.
I'll tell you what is tedious. Reading all this stuff. By the time the 3rd page (or, less) of "comments" roll around, I need a 60 horse power sorting machine to sift it all out.
A lot of these topics start off with good intentions, and by the time they get to the last page (which often times seem endless), the topic is so murky (if it is still ON topic), that the average schmuck like me doesn't know WHO or WHAT is right about the subject matter at hand.
Don't some of you guys work in corporations? Ever hear of bullet points?
How about this suggestion: after all the countless words and technical stuff, why can't someone PLEASE summarize the whole topic?
BULLET POINTS!
To quote Keith B: Sheesh!
The topic was "Comments on MFA"
So far it seems all the posts very much stayed on topic as "Comments on MFA", except yours Alan. You are following a discussion on the matter, not a technical manual on how to. Some of the posts were theories, ideas or questions. By the time you get to the end of a thread everyone has an opinion, and most likely expresed it. If someone summarized the whole topic, I am sure someone would chime in with another opinion.
Perhaps you could start a new thread about the random degredation of threads and how they wonder off topic and it should be sumarized. Please provide bullets with talking points as well and maybe everyone will try and stay on subject.
<span style="font-size: large;"]- Somehow I knew this would be one of the responses.
<span style="font-size: large;"]- At least you admit that there is random degradation of threads.
<span style="font-size: large;"]- They wander off topic.
<span style="font-size: large;"]- They should be summarized.
Thanks for agreeing with me.
Bullet. Points. Sounds like you're talking about flechette rounds? [:P]
While I generally agree with Rick (and subject drift and degradation is a characteristic of pretty much any forum), here's my summary:
- If your camera has AFMA, use it!
- Each lens + body combination must be calibrated separately (and lens + extender is treated as a separate lens).
- AFMA is most important for wide aperture and telephoto lenses, where DoF is thin and focus is critical.
- To correctly set AMFA, use a proper focus target (ideally a commercial tool, e.g. LensAlign, SpyderLensCal, etc.;Lensrentals.com rents out the LensAlign Pro) that is properly aligned to the camera, at a distance of 25-50 times the lens focal length.
- To set AMFA without a commercial tool, use a flat target with lots of detail, making sure it's parallel to the sensor.
- Take several shots at each AFMA setting (iteratively bracketing or stepping through every adjustment), and select the best one.
Hope that helps....
--John
Bullet. Points. Sounds like you're talking about [url="http://en.wikipedia.org/wiki/Flechette]flechette[/url] rounds? [img]/emoticons/emotion-4.gif[/img]
While I generally agree with Rick (and subject drift and degradation is a characteristic of pretty much any forum), here's my summary:
[list][*]If your camera has AFMA, use it![*]Each lens + body combination must be calibrated separately (and lens + extender is treated as a separate lens).[*]AFMA is most important for wide aperture and telephoto lenses, where DoF is thin and focus is critical.[*]To correctly set AMFA, use a proper focus target (ideally a commercial tool, e.g. LensAlign, SpyderLensCal, etc.;Lensrentals.com rents out the LensAlign Pro) that is properly aligned to the camera, at a distance of 25-50 times the lens focal length.[*]To set AMFA [i]without[/i] a commercial tool, use a flat target with lots of detail, making sure it's parallel to the sensor.[*]Take several shots at each AFMA setting (iteratively bracketing or stepping through every adjustment), and select the best one.[/list]
Hope that helps....
--John
<div style="clear: both;"]</div>
See how much clearer that is?
Of course the topic drifts, and I understand that. My point was that if it's got information that is useful (in this case, MFA), it's important to the vast majority of the others who read these things, to know where the thing is going.
I remember one thread long ago that ended up on Heisenberg's uncertainty principle. Not very useful for the hoi polloi.
Thanks, John.
It helps a lot.
Sorry Alan I couldn't resist.
I have to commend John, he gave you exactly what you asked for.
Since much of the last page and half was instigated by me....These are a few things I have learned or we discussed. (sorry I hate bullet points, numbering is so much better don't you think)
- Doing a lens calibration is better than not checking your lens at all.
- My home made target stinks, to find a better way I had a detail drawn up this weekend of one I could make and maybe even market because I can see a need for it. It was square with guides to center your camera and scales to see DOF. But sadly while researching it this week I found someone beat me to it.
- Which brings me to this.... Bryans review of the DataSpyderCal, there is a video that shows you how to use it on his review page. [View:http://www.the-digital-picture.com/R...l-Review.aspx]
- These guys have instructions as well. http://www.lensalign.com [View:http://www.lensalign.com/]
- Even if you do not buy a DataSpyderCal or Lensalign both have some good info you could apply to your homemade target.
- There is also a lens calibration tool that somehow uses your computer screen to calibrate. Not sure how it works, but to use an old phrase "there is more than one way to skin a rabbit" I have seen at least five different ways to calibrate your lens online. So far the methods with the Lensalign look the best to me.
- I posted earlier about adjusting your lens then shifting to live view to review your results in 10x, rather than taking a series of pictures. To sum this up, I think the final consensus was that it might work, but it would never be as accurate as the more detailed methods.
There is more that could be gleaned out of the post in this thread, but if we have a summary that points people to the right tools and instruction manual to do the job. Then people wont rely on our wandering thread to get all there info. Which is good.
Rick
Rick, thanks for your bullet points, too (well, numbers, but I like numbers just as well).
This discussion on MFA was important to me, because I ran into some of the same issues when I first started looking at adjusting my lenses.
The thread isn't just about discussion, but about learning and helping others. As I mentioned, sometimes, the message gets lost, which is why I like the summaries.
I appreciate the summary.
I thought it was a cat, and not a rabbit? Oh, well, rabbit cooks up easier and tastes better. []
Alan
I have heard it both ways, but to use the word Cat might offend both Cat Lovers and Animal Rights Activists. This way Rabbit just offends the Animal Rights Activists.
But on another note:
- Ijust recieved my $249 Lensalign Pro Plus. When I took it out of the box, I thought they had sent the wrong one and sent the $169.00 Lensalign pro. After looking this I found the only diffrence in the two is nothing. With the Pro Plus they send you the Lensalign Pro and you get a magnetic target that you put over your Lensalign Pro and a Longer Ruler.
- My first thought is that maybe I wasted the extra money on the long ruler. I went to the lensalign website and there is a tool that gives you the Minimum Average distance you set up the target. All my lens even the 500mm with a 1.4 extender at the minimum distance the tool says use the short ruler. Now if I go out to about 100' to do the setting on the telephoto's, only then does it recomend the longer ruller. Someday I might check mine at longer distances, but I think that may be taking "teadious" to a whole new level.
- I think the average photographer would never need the $249 Lensalign Pro Plus, and could save the extra $80. And if they found they needed it go back and get the longer ruler, whichit and targetcosts $99.
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