Hi all! I have a 5D3, and I just bought the new 100-400L IS II lens.

[LisaQ]

Hi all!  I have a 5D Mark III, and I just bought the new 100-400L IS II lens.  I have an EF 2x III Extender, and I can't get the lens to auto focus when using the extender.  Can someone help me with this?

[Skirball · Accepted solution]

Using a 2X extender doubles your minimum aperture.  The aperture of the 100-400 is 4.5 - 5.6, so if you double that it's 9 - 11.  The maximum the 5d3 can autofocus is f/8, and I believe that is only the center point (and with the firmware?  I don't remember). 

Long story short, no AF with the 2X.   With 1.4x the center point should work.

[Skirball · Accepted solution]

Wise choice.  In general, most find that the 2x diminishes image quality too much for their liking.  1.4x is usually better regarded.  From what I've read, it's gotten good results on the 100-400 II with the 5d3.

[ebiggs1 · Accepted solution]

LisaQ,

I am going a little further and say even the 1.4x extender is going to be problematic.  You are transforming the lens into basiclly an f8 560mm.  The camera will still struggle but it will do it.

Most people use their zoom lenses at the long end is why I say this.  Because why would you put an extender on a lens that already has most of the focal lengths without it? (100mm to 400mm vs 140mm to 560mm?)

Another concern is 560mm at f8 is going to be a trick to hold and get sharp photos.  Yes, it can be done but you will need practice in hand holding.  Or, better yet, get a tripod.

As a general statement I don't recommend folks buy or use tele extenders at all.  But if you must, only on lenses that are f2.8 or faster.  Another suggestion, if I needed a 400mm lens that could get me 560mm cheaply, I would prefer the EF 400mm f5.6 L prime lens with the 1.4x II extender.  It offers several advantages.  One being it is much lighter.

Good luck.

[ebiggs1 · Accepted solution]

LisaQ,

Also another point most, if not all, don't realize is when you put a 1.4x (or 2x) extender on any lens you multiply everything.

Yes, the focal length and that is nice but you also magnify all the bad, too.  So it becomes 1.4x (or 2x) times harder to use since you have to become 1.4x (or 2x) times better.  Shake, blur, accurate focus, etc, everything.

[Skirball · Accepted solution]

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@LisaQ wrote:

Thank you for your input.  You make a great point.   Much to think about!

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I recommend not spending too much time thinking.  Pick up the 1.4x, and give it a try, it's peanuts compared to a 100-400II and 5d3.  Yes, there are limitations and hurdles to extenders, but plenty of people use them with great results.  There's only one way to find out if it works for you.

[LisaQ]

how do i get on your fb page, ebiggs1?

[ebiggs1]

Just search for Ernie Biggs and you should fine it.  We also have a page for the school band. GEHS Trailblazer Band 

Both are public so you don't need any friend thingy but just send me a request and I will OK it if you want to.

School auditorums are a challenge.  Another reason to shoot RAW and use PS.  You can fix most things.

My son is the District Music Director of Bands.  We have four schools but I am mostly involved with the high school.

It is fantastic your daughter wants to do music as a career.   Both my son and I have attended The University of Kansas.  We are dyed in the wool Jayhawks!   

What year is she?  Tell her to play as much as she possibly can at any and every opportunity.  This is so exciting for both her and you.  Don't miss a minute of it.

[RobertTheFat]

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@ebiggs1 wrote:

Just search for Ernie Biggs and you should fine it.  We also have a page for the school band. GEHS Trailblazer Band 

Both are public so you don't need any friend thingy but just send me a request and I will OK it if you want to.

School auditorums are a challenge.  Another reason to shoot RAW and use PS.  You can fix most things.

My son is the District Music Director of Bands.  We have four schools but I am mostly involved with the high school.

It is fantastic your daughter wants to do music as a career.   Both my son and I have attended The University of Kansas.  We are dyed in the wool Jayhawks!   

What year is she?  Tell her to play as much as she possibly can at any and every opportunity.  This is so exciting for both her and you.  Don't miss a minute of it.

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We photographers are a versatile lot. Before I fell into computers as a career, it had crossed my mind to be a band director. I played cornet in junior high and French horn in high school and college. I still drag out my trumpet every Memorial Day and play "taps" at the seven or eight cemeteries and war memorials in our Boston suburb.

[ebiggs1]

Boston, Massachusetts USA         

[LisaQ]

Bob, I love hearing that you're still playing.  I hope my girls are the same way.  My grandmother was the church organist for 48 years.  My gpa played upright bass in a swing band for 27 years, my parents are both great musicians, and I was the music director at our church for 14 years.  It's so fun to see my girls loving music.  Besides our faith, it's one of the most precious things that is being passed down through our generations.

[ebiggs1]

When we were going through the state music contests and such, my son William told me it was really just luck.  But he said he noticed the more he practiced, the "luckier" he got. 

Now he is the one talking the kids to contest.  Of course, this is the start of contest season so here we go again.

We both play in the Olathe Symphony Orchestra. He is Principal trombone and I play 2nd trombone.  I am President of the Shawmee Concert Band and play 1st trombone. It is a local civic band where, Will my son, is the Music Director.

I can say Go Huskers!, now too.  Say hi to Herbie and Lil Red for me.    We played 1/2 time on your football field a time or two.

[ebiggs1]

Oh, BTW, tell Sara Jane all it takes is practice.

[LisaQ]

I'm glad she's getting to learn about the fruit of hard work through music!  How wonderful that photography and music are such a big part of your life!

[LisaQ]

Jayhawks!?!  My husband and I are Husker alums.  Our oldest is down at UNL now.  Since we're not in the same conference any more I can say: GO HUSKERS!  

I haven't loaded PS yet. Still learning lightroom, and it's been a blast.  I think I like editing as much as taking the pics.

Our youngest, Sarah Jane, is a freshman in hs.  She was an all-state clarinet player for the middle school kids last year.  She has the Elkhorn Band Olympics next weekend and had a jazz band competiton on Monday.  We're in the thick of it.  She told me last night she is starting to like to practice.  HALLELUJAH.  We're a bonafide band nerd family.  Our oldest was an all-stater in tenor sax.  She is a great piano player too.

[LisaQ]

It's the hawks that have made me want one.  They're hard to get close to.  Even if it helps a little, I will be glad.