Looking at the SpyderLensCal - review

[keith_cooper]

I've just been looking at Datacolor's SpyderLensCal.

http://www.northlight-images.co.uk/reviews/photography/spyderlenscal.html

Interesting and quite solidly built device - IMHO more than adequate for the task at hand. (YMMV!)

My personal choice might still be to start off with the Moire fringe pattern technique, but during testing I did come across some possible reasons that the pattern method might not work for some people.

[AFairley]

Based on my experience with a home-made knock-off of the LensAlign (I guess it's now a knockoff of the SpyderLensCal too now) the angle of the "ruler" is way too steep on the Spyder gizmo.

[Bart_van_der_Wolf]

Based on my experience with a home-made knock-off of the LensAlign (I guess it's now a knockoff of the SpyderLensCal too now) the angle of the "ruler" is way too steep on the Spyder gizmo.

If the SpyderLensCal ruler cannot be mounted at another angle, it seems that a 45 degree angle is indeed to steep (especially when used at 50x focal length). One of several things (adjustable angle) where the original LensAlign excels.

Cheers,
Bart

[keith_cooper]

I was looking at FL x50 since this is what Canon suggests in their own AF adjustment notes. There is no suggested distance in the SpyderLensCal info. I often use the 24-70 at ~2-3 metres, so checking at this distance seems reasonable.

At x25 there was no problem with the ruler angle.

However I found it quicker just to fire off a set of shots at different AF adjust settings and see what looked best :-)

Further experimentation led me to conclude that even at x25, some slight mis-alignment of the target was pretty irrelevant to my results (once again I'd point out that I'm just adjusting AF, not setting up a lens testing laboratory in my temperature controlled, vibration free underground lab ;-)  )

[mac_paolo]

FWIW, I bought the Datacolor one because of its price and the availability in Europe (for the LensAlign it has to pass from our custom, which is one of the slowest of the planet and add more or like 50% between duties and tax!)

The fixed 45° angle is way too steep. For the most of my lenses, even at full aperture, the DOF is so high that knowing what is really on focus is quite hard to tell.
Beside that, it's almost impossible to correctly align the focal plane of the DSLR as no help is given from the SpyderLensCal itself (while the LensAlign does help with that red circle alignment system).

So... I'm not even quite sure it helped my focusing or not. I mean... sometimes on the filed the focus is not achieved for low light conditions of just a few millimeters off the desired elements from the central focus point. It happens.
For those who can afford both the brands, go for the LensAlign, IMHO.

[Jan Morales]

I have both the SpyderLensCal and the LensAlign MkII, and there is one feature the LensAlign has that makes it much easier to use than the SpyderLensCal, at least for me. The LensAlign has small holes in the target that allow you to point it directly at your camera easily. I can look through the back of the LensAlign and aim it, and when I can see my camera lens through both holes I know it's parallel to my camera's focal plane. I don't have to worry about whether my camera and target are at exactly the same height or exactly level; they just have to be aligned with each other.

The SpyderLensCal does not have these holes so in order to perfectly align it with your camera you need to make sure both it and your camera are level and the same height. My back yard is not level and I don't have two identical tripods, so this is very hard to do, especially when you're doing multiple lenses and have to change the distance for each lens. It's way more frustrating than LensAlign.

You can see what I'm talking about here: http://michaeltapesdesign.com/lensalign.html. Go to the "How to use it." tab and click on #2, "Sight the camera to LensAlign".

[julianv]

The SpyderLensCal does not have these holes so in order to perfectly align it with your camera you need to make sure both it and your camera are level and the same height.

Alternatively, you could temporarily place a small mirror on the target, and use that to align your camera.

Here's another focus calibration product that looks promising, with a completely different approach:

FoCal

I have not tried it.

[mac_paolo]

Here's another focus calibration product that looks promising, with a completely different approach:

FoCal

I have not tried it.

Brilliant!
What a pity... Windows only

[julianv]

The developers of FoCal are hoping to have a Mac version in 2Q 2012.  That would imply a release within a few weeks.

Note that bobkeenan posted a positive review of FoCal, linked in this forum:

http://www.luminous-landscape.com/forum/index.php?topic=67459.0