135mm + 1.4 extender _VS_ 70-200mm f/2.8 IS mkI

[neuroanatomist]

From my unscientific tests... it seems that OOF blur is always more with the TC since you need to stand further back.

Also I am not 100% sure you can use standard DoF calculators for TC calculations (Maybe I am wrong again).

Then you need to do some scientific tests.   

FWIW, standing further back makes your DoF deeper, meaning less OOF blur, all else being equal.

Yes, the standard DoF calculators work just fine with a TC.  For a 2x TC, just double the focal length and set the f/numebr two stops narrower, and you'll get the correct DoF calculation

This is not scientific but I came across this... why is Kenko claiming the DoF will be lower pls. see their description.

Yes, you can get shallower DoF with a TC - but not for the same framing.  What Kenko means is that you get 1/2 the DoF assuming you don't change the distance to the subject. Compared to 135/2, at the same distance 270/4 gives half the DoF...but frames a much smaller area. 

For the most Part adding a 1.4x TC does add a stop of light, but no one has been able to convince me that the aperture (which determines DoF) magically closes down by adding a TC. Ye sthe system overall will lose a stop of light and "act" like a f/2.8 so that the camera can compensate for lower light transmitted, but the Aperture will stay wide open.

Ok, I think I see the confusion here...

What do you mean by 'aperture'?   Of course the physical aperture doesn't 'magically close down' - the iris diaphragm (the hole surrounded by aperture blades) doesn't get any narrower by attaching a teleconverter.   But the f/number is NOT the same as the physical aperture.  The reason there's a slash or a colon in the f/number is because it's a ratio of focal length to physical aperture diameter (both in mm, so the f/number has no units).  A TC doesn't change the physical aperture, but it does double the focal length (and cannot make the physical iris diaphragm larger, obviously), and that changes the f/number.  I think this is the point causing the confusion here - the physical aperture doesn't change, but the f/number (which many people use synonomously with aperture) does change when you add a TC.

Break out your calculator.  A 135mm f/2 lens has an iris diaphragm diamater of 67.5mm (135 ÷ 2).  Put a 1.4x TC on it, it's now a 189mm lens, and the iris diaphragm diamater remains 67.5mm.  189mm ÷ 67.5mm = 2.8.  Put a 2x TC on it instead, it's now a 270mm lens, and the iris diaphragm diamater remains 67.5mm.  270mm ÷ 67.5mm = 4. 

So, put a 1.4x TC on a 135mm f/2, and it's not 'acting like' a 189mm f/2.8 lens, it actually becomes a 189mm f/2.8 lens, and has the OOF blur of a 189mm f/2.8 lens.  Put a 2x TC on it and it becomes a 270mm f/4 lens.  The f/number has changed because the teleconverter increases the focal length.

[dirtcastle]

So my original question was specific to the MARK I version of the 70-200mm f/2.8 L IS.

Is the 70-200mm f/2.8 L IS MKI really that bad? Seems like everyone was loving it until the Mark II came out.

[K-amps]

Thanks for taking the time John..  I came out of this learning something new.  I always thought of the Physical aperture as the the F-Stop number. The example helped!

I guess what I was experiencing was that perhaps my framing had changed making it seem as if the DoF had thinned out, which it might have, while keeping the same distance to subject. This would have explained both what I experienced and what you have said.

[Cannon Man]

I just sold my 70-200 2.8 IS II and bought a 135 2.0 to replace it. (and also 35 1.4)
The 70-200 was too big and heavy for a walk around lens and i love the 2.0 aperture in the 135.

So i would recommend a 1.4  extender although i dont have experience of using it but i plan to get one.

[Mt Spokane Photography]

So my original question was specific to the MARK I version of the 70-200mm f/2.8 L IS.

Is the 70-200mm f/2.8 L IS MKI really that bad? Seems like everyone was loving it until the Mark II came out.

I''ve had several of the 70-200mm mk I IS versions.  Certainly, they are good lenses.  Their weakest spot is at or near 200mm, and since you would likely be using a TC with it at or near 200mm, it is disappointing. 
 
The non IS and the MK II are much better at 200mm and take a TC reasonably well.

[hyles]

I have both 135 f2 and 200 2.8. The 135 does not really like TC (i tried it with the 2x) . It is OK sometimes but IQ decreases a lot. 200 2.8 works better with TC.
200 2.8 is awesome, I think i like it more then the 135. And its bokeh is fantastic.
I would go for the 200 2.8
Diego

[Matthew19]

+1 on the f/4 IS. Wonderful lens, considered sharper than the 2.8 IS V1 and very close to  the vII. Half the weight, half the size, half the price of v2. My only issue is focus breathing when used for video.

-Matt // The Film Poets
www.thefilmpoets.com

[Vonbon]

I have both 135 f2 and 200 2.8. The 135 does not really like TC (i tried it with the 2x) .

135 does not like 1.4x too. I tried with version II and III as well. 70-200 f4 works better with extender and it's about the same price with 135. But for low light & fast wide open, 135 is very versatile.

[Daniel Flather]

Ok, I think I see the confusion here...

What do you mean by 'aperture'?   Of course the physical aperture doesn't 'magically close down' - the iris diaphragm (the hole surrounded by aperture blades) doesn't get any narrower by attaching a teleconverter.   But the f/number is NOT the same as the physical aperture.  The reason there's a slash or a colon in the f/number is because it's a ratio of focal length to physical aperture diameter (both in mm, so the f/number has no units).  A TC doesn't change the physical aperture, but it does double the focal length (and cannot make the physical iris diaphragm larger, obviously), and that changes the f/number.  I think this is the point causing the confusion here - the physical aperture doesn't change, but the f/number (which many people use synonomously with aperture) does change when you add a TC.

EF 200mm f2.0 has a 100mm apature wide open (200/2=100)
Add the 2.0 TC and you have a 400/4 lens
400/4=100mm apature,  the size is the same but it's relation to the focal length changes.

[discojuggernaut]

I have the 135mm + the 70-300L and think they are a great combo.  Not that i usually take them both in the same bag at the same time, but they give me two distinct options in the tele range, and either will be able to play backup for the other if i don't have both.  I consider them day/night lenses:

135 - uber sharpness/IQ, low light, portrait, bokeh
70-300L - uber focal range, IS, sports/nature

Both have rocking AF, and are within about 35% weight, size, and price of each other.

My preference is for these two over a 70-200 2.8 II, f/4, or some combination of extenders.

[Ew]

I have both 135 f2 and 200 2.8. The 135 does not really like TC (i tried it with the 2x) . It is OK sometimes but IQ decreases a lot. 200 2.8 works better with TC.
200 2.8 is awesome, I think i like it more then the 135. And its bokeh is fantastic.
I would go for the 200 2.8
Diego

I've tried the 135L w/ the x1.4v2 - and I didn't seem to notice a big hit on autofocus, definetly need to bump up shutter speed though.  Just a few test shots here and there, but planning on seeing how this works out during the week.  Would be interested in seeing a direct comparison with the 200 2.8L.

[crasher8]

Yet google the 135+ 1.4 TC combo and you get a ton of folks loving this combo. I say buy things from a reputable dealer such as B&H or rent and see for yourself.

[RLPhoto]

I've been wanting a 70-200II for awhile now and every time I pick one up I realize why I've been waiting so long. It's just heavy to lug around, white and 2000$.

Unless you do a lot of action photos, get the 70-200 but you will always have to lug it around. With the 135L, you just take a tiny little tele converter.

[crasher8]

I've been wanting a 70-200II for awhile now and every time I pick one up I realize why I've been waiting so long. It's just heavy to lug around, white and 2000$.

Unless you do a lot of action photos, get the 70-200 but you will always have to lug it around. With the 135L, you just take a tiny little tele converter.

+1

[TWI by Dustin Abbott]

I too like the 135L + Kenko Pro300 combo.  It makes for a very effective almost 200mm prime (at 189mm is has basically as much reach as the 70-200mm zooms at 200mm).  It is still very hand holdable for me.  Sharpness, color rendering, and focus speed are still all very good.

It is also great for head shots, as the minimum focus distance does not change with the TC and allows for tighter framing because of the extended focal length.