How to read MTF chart

[dmbers892]

So I have a question about the thick dotted lines. The soft focus is better when they are more seperated from one another than when they are closer together?

[Joegioamani]

MAny thanks for your lecture... I really appreciate your effort and time. May I ask what is the thin dotted lines represents? You explained thick solid lines as contrast, thin solid lines as resolution, thick solid lines as focus quality.

[treehugger3615]

In this example, does it mean the lens is sharpest at aprox.12-13mm f8 from the center? There is a little "spike" in the blue line.

[0102vuleak]

A very good quality video, informative, and no shadows, Lol!!! :-D P.S. Thanks 4 the information, and I learned something new today. :-)

[petertwang]

So while it is true that divergence of these lines often indicates poor background blur, it is important to realize that one needs to look at both lines, not just the solid one, to judge contrast or resolution. The 17-40/4L @ 14mm shows good sagittal contrast but poor meridional contrast, meaning the lens tends to blur the image in a direction in/out from the image center; and this is why the background blur might look undesirable.

[hooptyndablowfish]

@petertwang - At the end of the day what matters most is composing brilliant photos that take your breath away. Most of the people who take those photos don't spend much time geeking out over MFT charts. They concentrate on issues revolving around light, shadow, contrast etc.

[petertwang]

The explanation of the dotted vs. solid lines is inaccurate. The solid line represents sagittal MTF and the dotted represents meridional MTF, so these are equally important when judging contrast (10 lp/mm) or resolution (30 lp/mm). If one is lower than the other, it means that the lens doesn't perform equally with respect to these two directions, and consequently, this is a sign of astigmatism.

[mAdHaTTer3392]

Ummm....what?

[duck52va]

Very nice, thanks

[dhel258]

great video! thanks for sharing!

[duanebass]

Excellent!

[Fetishnicola]

Great video.Thanks.

[glennwih]

Audio track is off use mpeg4 only for youtube.

[JeffDM]

@glennwih I think the key word here is HTML 5. Those interested should enter the trial, do a search for YouTube HTML5

I think the audio/video sync is still slightly off, though it's noticeably better.

[glennwih]

@JeffDM MPeg-4 and or h.264 are the same family of codecs. Mpeg4 is still the best for video transfer via the net. mpeg-5?

[JeffDM]

@glennwih I couldn't find any way to turn on MPEG-4 directly. My impression is that turning on HTML 5 forces the videos to be MPEG-4

[freemancarl]

GREAT!!

Thanks a lot 4 sendin. Appreci8 it.

Cheers! :)

[ExplicaTodoConMac]

awesome



[edzelf25]

where'd you get that cool laptop stand and camera mount? I need one.

[FrostyTheBeerMan]

@edzelf25 B&H Photo and Adorama sell them, but they are pricey.

[epicsalesvideos]

Thanks. This is super helpful.

[AkkarinKnight]

audio lags from video a little.

[dez5]

@AkkarinKnight

It's a Karate Flick.

[weaponeer]

nice video