# 85mm f1.8 requires A LOT of contrast to focus.



## Viggo (Oct 9, 2016)

Hi guys!

I recently bought a 85mm f1.8. I actually like it, to my surprise better than I liked the L, but there's one BIG issue; I needs a lot of contrast to focus. I mean, I can use One Shot in very dark settings and nail focus easily. But faces in normal flat outdoors light and what I consider bright and normal indoor light it just doesn't hit at all. No use to have the faster AF when it doesn't lock at all.

Is this normal with it?

I tried 20 shots of my daughter with a B1 light and not one shot has sharp eyes. I then switched on the modeling light and suddenly everything is sharp and great. Went out with my son an hour or so before sunset and I didn't have a single sharp shot. And again using One Shot and a very contrasty subject in the same light works.


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## Sporgon (Oct 9, 2016)

I found accurate focus with the 85/1.8 very frustrating, and I've had three over the years, they were all the same. I never really associated it with low contrast, but that's not to say that wasn't the case. All I can tell you is that I find the 100/2 to be much better in this regard.


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## Viggo (Oct 9, 2016)

Sporgon said:


> I found accurate focus with the 85/1.8 very frustrating, and I've had three over the years, they were all the same. I never really associated it with low contrast, but that's not to say that wasn't the case. All I can tell you is that I find the 100/2 to be much better in this regard.



Thanks for your reply  I've been testing more this evening and darkness is not an issue if subject has contrast. And it's spot on with my daughters makeup doll with big blue eyes, so I'm sure the issue is flat light and or lack of contrast on the subject. 

I was considering the 100 also, but it's just that bit too long and close enough to the 200 where I would of course use that


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## neuroanatomist (Oct 9, 2016)

I've only used the 85/1.8 on my 7D, but I found it to focus well. Here are a couple of shots, one outdoor and the other in 'typical' ambient indoor lighting. Both are at f/1.8 with countable eyelashes.


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## rfdesigner (Oct 9, 2016)

I have the 100 f2.0 and on my 6D it's good until Auto-ISO would be looking for around 25600 at which point I need to care more about finding a nice pronouced high contrast feature to focus on.. or I just MF. (centre point AF, I rarely use the outer points)


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## Viggo (Oct 10, 2016)

Thanks guys! I will try and find a way to make it work for me, because I really like otherwise. And AF in harder light is very very good. I'm trying hard to not compare it to my other lenses, and iq wise it's easy enough, but can't help to think the AF should hit better. 

Here's a jpeg snap that was pretty sharp at 1.8 from yesterday, raw converted in camera so apologize for that : she was very cold since she wouldn't put on clothes because "it isn't cold outside". ;D


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## wsheldon (Oct 10, 2016)

I've had pretty good luck with my copy on a 6D, but I did notice when doing AF micro adjust with several of my lenses that the 85/1.8 was the least consistent and required several tries and averaging. There may be a little more slop in the AF system than other fast lenses. It is an older design (1992), but about the same vintage as the 100/2.0. My 135/2.0 is far more consistent. Great lens for the money, though, and fun to throw in for travel since it's so light and compact.


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## Maximilian (Oct 10, 2016)

Hi Viggo! 

I use my 85/1.8 with a 5D3 and a 100D/SL1. I like that FL a lot and shot in every kind of light conditions, esp. available light indoors with dark light, e.g. weddings and parties.
Except for the mediocre AF system of the 100D and everything that happens with such a shallow DOF I've never recognized any focusing issues.


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## Viggo (Oct 10, 2016)

Thanks for your input guys, much appreciated !

I've taken several hundred pictures indoors with grey and dark weather outside and everything with contrast sticks wonderfully. I guess it's the old "kids faces and AF forget it" -ghost that's back again


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## neuroanatomist (Oct 10, 2016)

Viggo said:


> I guess it's the old "kids faces and AF forget it" -ghost that's back again


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## Viggo (Oct 10, 2016)

neuroanatomist said:


> Viggo said:
> 
> 
> > I guess it's the old "kids faces and AF forget it" -ghost that's back again



LOL ;D


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## Mt Spokane Photography (Oct 10, 2016)

I took many thousands of photos with mine before selling it and going to all zooms. I never noticed a focus issue.


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## Viggo (Oct 10, 2016)

Mt Spokane Photography said:


> I took many thousands of photos with mine before selling it and going to all zooms. I never noticed a focus issue.



Took it to soccer practice today. On my son it frontfocuses about 70% of the shots, but the kids in yellow wests were 85% dead on and the rest acceptable.

I will be using the 85 mostly with my lamp, so I'll just have to use the modeling light.

Maybe I'm just spoiled with the 35 L II and the 200 f2..
I


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## cpsico (Oct 10, 2016)

I have the same love hate relationship with my 100 f2, despite being a fast lens I have never found it reliable in low light, low contrast.


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## AJ (Oct 11, 2016)

I used to use this lens at weddings for speeches and portraits, often in lousy lighting conditions. AF worked great.


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## Luds34 (Oct 11, 2016)

AJ said:


> I used to use this lens at weddings for speeches and portraits, often in lousy lighting conditions. AF worked great.



+1 AF has always been excellent with this lens for me. Granted, my lens is only ~5 years old and sometimes I have this theory that I think they have "dialed" them in more in recent years. I've used this lens on extensively on a number of bodies, most recently a 70D and 6D and it tracked and focused flawlessly. The 70D especially, as I could lock in with the focal point, hold down BBF in AI Servo while shooting at f/2 and just get hit after hit after hit. Static shot in low light never an issue either. For me personally, if focus speed/accuracy has been in question, this is a go to lens.


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## Maximilian (Oct 11, 2016)

Viggo said:


> ...
> Maybe I'm just spoiled with the 35 L II and the 200 f2..
> I


I suppose you should take this seriously into account. 
Of course the 85/1.8 cannot compare with those two in any kind of aspect.
That's why I am quite curious about what a new Canon approach on this classical lens will bring to us.
But I suppose we'll have to wait a few years (at least one) to see a successor. 
But I have no urge to change, even if there is a really good Tamron with VC.


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## Viggo (Oct 11, 2016)

Thanks for the input!

Again, IQ wise I'm happy and not comparing it at all the two others. But basic AF should be better. But if you have ever shot kids, that is the main issue and it sets a much higher demand than anything else. Shooting sports is usually bright colors and contrasts on an even background. But small faces with very little shape and contrast in grey outdoor light is worst case. 

Everything but the kids I try to focus on under the same light sticks. 

I'll just have to find a way to make it work best.


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