Focus Chart Setup

Not sure where to post this other than here (I apologize in advance if this belongs in another section).

I want to test my camera and lens to make sure it focuses correctly (I am sure its operator error and not my 550D or the 50mm 1.4). Been having some focusing issues...

The chart I got from focustestchart.com in the instructions tells to setup the camera on a tripod at 45° angle to the test chart. How would I measure the angle to make sure its done properly? I understand what I need to do and how to set up just not sure how to measure the actual angle correctly of the lens (actually I assume it would be the sensor) to the test sheet.

A 45°angle is one that bisects the vertical and horizontal planes:

I know for me its a simple case of using my iphone on top of the lens to get roughly 45 degrees with an app called free spirit. Its a pretty precise level and will tell you when your at 45 degrees.

Mike thank you, I am well aware what a 45 degree angle is, I was looking for a precise way to measure it (which you say is unnecessary).

Now the iPhone idea I can defiantly do since the 45 angle does not need to be exact.
Thank you.

In addition to the test chart, I'd suggest you check out this sticky:

https://photography-on-the.net/forum/showthre​ad.php?t=857871

The second post lays out a fairly in-depth approach to evaluating the focus performance of you camera/lens combo, as well as "seeing" other characteristics at work.

Hope it helps!

Hi All,
I did the test this morning on the new Sigma 30mm F/1.4 on Canon 60D.
They are at below link:
http://sdrv.ms/V7SkHa

Is it normal? or, my lens has problem. I really appreciate if someone can help to confirm. Thanks, Best Regards,

The result showed:
F Result
1.4 small front focus
1.6 small front focus
1.8 small front focus
2 Good
2.2 Good
2.5 Good
2.8 Good
3.2 Good
3.6 Good
4 Good
4.5 Good
5.6 Good
7.1 Good
8 Good
My question is: is it normal to have light front focus at the wide open below F1.8?
or, my lens has problem, and I should return it?
BH is very good, they told me I can send it back for exchange.
however, if the above result is normal, then, I dont' want to send it back as when I google it, look like others people lens result are much worse.
in my case, at F1.4, 1.6, 1.8, it still can focus fine on object. on the test chart, the line "This text should be perfectly in focus" is in focus, just not very sharp. Everything above this line is fade, everything below the line is in focus, clear, sharp. Is it normal?

At wide apertures sometimes you will lose sharpness (most times in fact) as lenses don't perform well at their extremes in that regard. You'll often have to stop down to find a sweet spot of a lens. If it is nailing the focus then be happy that you have a good lens.

I'll not click the link though I'm afraid as first posters linking to an unknown site are an unknown quantity and so I'll never click the links. Sorry!

When you say (when shooting at wide apertures) " on the test chart, the line "This text should be perfectly in focus" is in focus, just not very sharp. Everything above this line is fade, everything below the line is in focus, clear, sharp" , well like Mike says above this can be normal. I don't have your lens, but a lens that is nice and sharp at the widest apertures, well, they typically have had a lot of engineering and special processing to get them to that point, and consequently are going to be quite expensive, you know, "special"!

Some Canon "L" lenses have a good reputation for that degree of sharpness. On the other hand, take the inexpensive Canon 50mm f/1.8 -- it actually has a good reputation for sharpness, and in fact within its "sweet spot" it is quite sharp. But wide open, not-so-much, you have to stop down to get the sharpness. Shooting it at f/2.8 or narrower, you can get very pleasing sharpness.

So, from what you describe I'd say your Sigma is giving pretty "normal" results, especially since it sharpens up by f/2!