I have been debating two of these lenses for my 5D mk III for a long time and actually purchase the 85 knowing that a friend would happily buy it from me if I decided it was too short. Took out a loan of the 100/2 and 135/2 from CPS and had a chance to compare all three today. Here's my report:
Images first - thoughts after the samples

Comparison shot - 85 and 100 have almost identical builds; 135 significantly larger though not heavy at all


My daughter served as model and I tried to replicate the conditions with each lens. These were shot as I would normally use each lens - no test charts here As luck would have it, my daughter had on the perfect outfit to torture test purple fringing

135


100


85


135


100


85


100


85


135


100


85


135


100


85


Thoughts:
85mm - bit short for my taste. most purple fringing but easily controlled in LR 4.1. Nice indoors. Feels like a 50 did on my 50D

135 - bit long for my taste. not as 'magical' as I thought it would be. not worth twice the cost of the 100/2 in my opinion. way too long indoors. was able to get a tiny bit of purple fringing out of it in one scene so this is definitely a 'class' issue - all tele primes seem to have some amount

100mm - just right thought the bokeh was damn nice on it and as good as the 135 for all intents and purposes. perfect length - especially for young kids it seems there is a distance at which you are too 'in their face' and another where you are 'too far to interact with' - this seemed to lie right in the middle. I think you can see that in the expressions I got from my model. There was some purple fringing on this one - far less than the 85 (half if you use the sliders as objective measures in LR).

Hope that helps anyone else in the market for a Canon Tele-Prime. Feel free to ask any questions s

While for me the 135L is the better lens and I made the right choice to move to it, I did love my 100 f2 - it's the only lens I have ever truly regretted selling (and the copy I had was fabulous - I got it as a BGN from KEH and it was banged up on the outside, but very sharp).

Enjoy!

Great test, thank you!! I am in this exact predicament, and my kids are my primary subjects. My 24-70 is great but I'm just not in love with it. I do see a slight bokeh advantage in the 135L, but at more than twice the price I could get over that. The very first picture reminds me of a shot I took with the 300/2.8 I rented. (sigh)

I was wondering about these three focal lengths, I shall take this as my answer.

By the way, I can see that my 70-200/2.8II's bokeh is noticeably busier.

This is a great "senior portrait"!



And this is ridiculously cute.

Thanks for the comparison!

Do you find that teens want you to be farther away than younger kids?

Originally Posted by nak Thanks for the comparison! Do you find that teens want you to be farther away than younger kids?

No idea...I'll update the post in 10 years
I only shoot my kids and then do landscape work otherwise.

Thanks for this interesting test.

Your daughter is adorable.

Originally Posted by Tommyboy Your daughter is adorable.

I dont know about the lenses, but your daughter is very cute! Great and fun shots. We need to do more of this!

+1 on the adorable daughter - you may have been "only" testing lenses, but you got a great series of images in the process! :)

Thanks everyone!

Yeah, assuming all lenses are decently sharp the big factor for me is bokeh quality..especially with "busy" backagrounds..like leaves on tree. compare the bokeh 135,100,85 on this set:



The 85 is a bit harsh while the 100 is acceptable and 135 is creamy smooth.

Yah. I was pleasantly surprised by the 100s performance in regards to bokeh on the street shots as well. The car in the background was as pleasingly smooth as the 135.

I would love to see the 100/2 vs the 100mm f/2.8L IS USM Macro

I have both the 135 and 100. I use them mainly for reportage, rather than portraits, and both are great, although the 135 is better. In the right situation you can get huge beautiful bokeh balls in the background:

I took the 135 out at sunset with both kids. We had beautiful golden Summer light and the lens performed beautifully. That being said, I just ordered the 100/2. In the end, I think it offers 90-95% of the 135's quality at 50% of the cost.

Originally Posted by DeVerm I would love to see the 100/2 vs the 100mm f/2.8L IS USM Macro

http://www.the-digital-picture.com/R...mp=0&APIComp=0

Originally Posted by eoren1 I just ordered the 100/2. In the end, I think it offers 90-95% of the 135's quality at 50% of the cost.

I agree, the 100mm f2 should be fine for portrait work