topic Re: soft focus problems with 70-200 2.8 lens in EF & RF Lenses

soft focus problems with 70-200 2.8 lens

anguslincoln — Fri, 25 Jul 2014 01:05:48 GMT

I am wondering if I am expecting too much image clarity and focus from my 70-200 mm 2.8 lens. I have been shooting a lot of birds with it from as close as 2 meters out to 50 meters.I have some fantastic results, but focusing seems to be inconsistant . I use it hand held mostly with good support at fairly high shutter speed when the natural light supports it. I was hoping to have less soft focus at the longer distances of 20+ meters. Is this lense capable of sharp focus at those distances if propper exposures are used ?

Re: soft focus problems with 70-200 2.8 lens

ebiggs1 — Fri, 25 Jul 2014 13:46:30 GMT

What camera? Which 70-200mm?

That asked, are you using center point focus?

The EF 70-200mm f2.8 L IS II is very sharp (at least mine is). As sharp as can be had with a lens like this. As a matter of fact it is the best lens made.

Re: soft focus problems with 70-200 2.8 lens

cale_kat — Fri, 25 Jul 2014 14:52:50 GMT

Your ability to hold a camera steady might be insufficient at 20 meters. Use a tripod, properly secured for stability, and report back. You haven't done enough testing to have drawn reasonable conclusions about the lens as of yet.

Just my 2 cents.

Re: soft focus problems with 70-200 2.8 lens

anguslincoln — Fri, 25 Jul 2014 16:19:43 GMT

I agree and thanks for the reply....being new to this forum, I realize now, I could have had found a wealth of knowledge from reading about similar issues that others have already diagnosed. There is much to learn from all you nice people here ! I am in Brasil right now and I only brought my monopod. As soon as I can get my hands on a tripod, I will do some further testing. Affordable equipment is not so easy to come by !

Am I correct in thinking that by making my aperture smaller and keeping the shutter speed above 600 or so will improve sharpness, even though I will need a higher iso setting ? Up until now, I have always tried to keep the iso as low as possible to achieve the best clarity, but after reading answers to problems here on the forum, I see that this may not be the best theory.

Re: soft focus problems with 70-200 2.8 lens

cale_kat — Fri, 25 Jul 2014 16:33:22 GMT

You know the mechanics well enough, IMHO, but 1/600 might not be fast enough for your purposes. My camera will shoot 1/8000 of a second! Absolutely unheard of when I first took up photography.

Re: soft focus problems with 70-200 2.8 lens

anguslincoln — Fri, 25 Jul 2014 16:59:29 GMT

Wow ! I haven't tried anything that fast ! My typical subjects are birds and and critters you might come across walking through the forests here ! I keep two 7D's with me mounted with the 70-200 and the 100mm macro. I am really wishing I had the tripod I bought for the trip here, but space was limited. One of the challenges I am dealing with is constantly changing light ! The forest has overall darkness with places of intense brightness at times ! Unfortunately, the birds seem to prefer the shady parts. But every once in a while, I get lucky !

Re: soft focus problems with 70-200 2.8 lens

cale_kat — Fri, 25 Jul 2014 20:14:14 GMT

Sounds like great fun when you get your shot. A little reading for when you're bored...http://www.lensrentals.com/blog/2009/08/how-to-get-sharp-telephoto-images

Good luck.

Re: soft focus problems with 70-200 2.8 lens

ebiggs1 — Sat, 26 Jul 2014 15:20:03 GMT

Big telephotos have a learning curve. The bigger tele, the longer that learning curve will be. And 1/8000 is not the answer. Usually? Mirror slap is violent at that speed by necessity. It by itself can add vibraton.

Also the IS is varibile, one stop is pretty good, two stops isn't as good and three stops not as good as two, and so on.

Switch IS off on a monopod or tripod.

The key here is to try several different things and shoot a lot. Keep track of what works and only read what you need to to get the basic knowledge. You really can't leanr photography from a book. You must shoot and a lot as said.

There are a lot of keyboard-photographers, don't become one of them.

Re: soft focus problems with 70-200 2.8 lens

RobertTheFat — Sat, 26 Jul 2014 16:13:18 GMT

@ebiggs1 wrote:
Big telephotos have a learning curve. The bigger tele, the longer that learning curve will be. And 1/8000 is not the answer. Usually? Mirror slap is violent at that speed by necessity. It by itself can add vibraton.

I'm no expert on shutter mechanisms, but the assertion that mirror slap is in any way related to shutter speed surprises me to the point of disbelief. The shutter curtain shouldn't start to move until the mirror is out of the way, and how long that takes should be a constant for any given camera. Manufacturers try to get the mirror out of the way as quickly as possible to minimize lag, but lag is undesirable at any shutter speed.

Also the IS is varibile, one stop is pretty good, two stops isn't as good and three stops not as good as two, and so on.
Switch IS off on a monopod or tripod.

On a tripod, yes - although some lenses are apparently smart enough to recognize when shake is not an issue. But on a monopod? That's far from obvious. A monopod, used correctly, should greatly reduce shake, but it can't eliminate it altogether.

The key here is to try several different things and shoot a lot. Keep track of what works and only read what you need to to get the basic knowledge. You really can't leanr photography from a book. You must shoot and a lot as said.
There are a lot of keyboard-photographers, don't become one of them.

That I can agree with!

Re: soft focus problems with 70-200 2.8 lens

ebiggs1 — Sat, 26 Jul 2014 16:40:17 GMT

I am going to break a rule to not argue a point wiht other forum users but you seem to be a pretty reasonable guy.

Cameras that can generate the insanely high shutter speed of 1/8000 have by design mirrors that move very much faster than older bodies that could not reach that speed. There is no point in being super fast for a 1/1000 or even 1/2000 shutter.

You don't want a camera that opens it's mirror and waits for a fraction of a second for the mirror to stop rebounding when you want or need 1/8000 sec. A mirror can take as long a 1/30 to stop rebounding. The camera is shaking all this time.

Is 1/8000 better than 1/80? Absolutely but it in itself is not the answer. The answer has several aspects, not shutter speed alone.

As in all electronics IS is varible. It will works better at a 1-stop disadvantage than it will at a 4-stop. That is just the way it is.

When the manufactuer says the lens has a 4-stop IS feature, they are really stretching the spec. Does it work at 4-stops, yeah, but is it as good as at 1-stop. No, it is not.

The IS function should be turned off on a tripod and even a monopod. The IS can actually work against you as most lenses have no idea wheter they ae being hand held or not. Now if you don't want to turn yours off, please, feel free to leave it on and shoot away.

Re: soft focus problems with 70-200 2.8 lens

RobertTheFat — Sat, 26 Jul 2014 16:54:45 GMT

@ebiggs1 wrote:
I am going to break a rule to not argue a point wiht other forum users but you seem to be a pretty reasonable guy.

Thanks. Did you see that I've just become a "Frequent Contributor"?

Cameras that can generate the insanely high shutter speed of 1/8000 have by design mirrors that move very much faster than older bodies that could not reach that speed. There is no point in being super fast for a 1/1000 or even 1/2000 shutter.
You don't want a camera that opens it's mirror and waits for a fraction of a second for the mirror to stop rebounding when you want or need 1/8000 sec. A mirror can take as long a 1/30 to stop rebounding. The camera is shaking all this time.

Is 1/8000 better than 1/80? Absolutely but it in itself is not the answer. The answer has several aspects, not shutter speed alone.

As in all electronics IS is varible. It will works better at a 1-stop disadvantage than it will at a 4-stop. That is just the way it is.
When the manufactuer says the lens has a 4-stop IS feature, they are really stretching the spec. Does it work at 4-stops, yeah, but is it as good as at 1-stop. No, it is not.

The IS function should be turned off on a tripod and even a monopod. The IS can actually work against you as most lenses have no idea wheter they ae being hand held or not. Now if you don't want to turn yours off, please, feel free to leave it on and shoot away.

Well, I just bought the new 16-35mm f/4L IS lens (not even out of the box yet). You can't turn off the IS, so I hope it knows whether it's hand-held or on a tripod! (As it happens, I have three tripods and a monopod, but I rarely have occasion to use any of them. So maybe it won't matter.)

Re: soft focus problems with 70-200 2.8 lens

Stephen — Sat, 26 Jul 2014 17:11:33 GMT

Hey guys!

For the last few years, some of our lenses actually do know whether they're on a tripod or not, so if you leave the IS on, and the lens doesn't detect movement, it'll automatically turn off the IS. I won't pretend to know how it works (maybe an accelerometer), but if you want to geek out, I'd be willing to bet our Tech Support folks know exactly how it works and which lenses have the feature, and they'd love to talk to you about it!

If you wanted to talk to them, they're at 800-OK-CANON

Re: soft focus problems with 70-200 2.8 lens

cale_kat — Sat, 26 Jul 2014 17:22:39 GMT

@ebiggs1 wrote:
Big telephotos have a learning curve. The bigger tele, the longer that learning curve will be. And 1/8000 is not the answer.
@ebiggs1 wrote:
Is 1/8000 better than 1/80? Absolutely but it in itself is not the answer. The answer has several aspects, not shutter speed alone.

Sounds like you'd like to have it both ways. Not the answer or maybe part of the answer. I'd like to know which.

Re: soft focus problems with 70-200 2.8 lens

ebiggs1 — Sat, 26 Jul 2014 22:49:15 GMT

"Well, I just bought the new 16-35mm f/4L IS lens (not even out of the box yet). You can't turn off the IS, so I hope it knows whether it's hand-held or on a tripod! (As it happens, I have three tripods and a monopod, but I rarely have occasion to use any of them. So maybe it won't matter. 🙂 "

Well, Bob from Boston, I bet it is new enough that it does have the intelegent IS. It is a great lens, BTW, and you will love it.

Actually the vast majority of lenses that do have IS do not know when to turn themselves off. Despite the post by the Canon rep. The fact of the matter is a significant number of photographers use lenses made by other manufactures and their lenses have no clue. It is a wonder that any of them work at all.

I doubt IS on a 16-35mm is as big a helper as it is on a 500mm lens. That must be taken into consideration.

My recommendation to you is the try it both ways. Get out your biggest tele put it on a tripod and shoot (a lot of photos).

Keep track. Back in the day we had to learn by trial and error as there was no internet to tell us every little nuance of photography.

And I still believe it is the best way to learn. If you don't like my thoughts on the subject, you will quickly decide for yourself.

It's what makes photography so interesting, isn't it?

I am turning green with eny of your new 16-35mm, please let me know how you like it.

Re: soft focus problems with 70-200 2.8 lens

ebiggs1 — Sat, 26 Jul 2014 22:50:49 GMT

"Did you see that I've just become a "Frequent Contributor"?"

Congratualtions. I didn't see it but I do now!

Re: soft focus problems with 70-200 2.8 lens

bento2 — Wed, 30 Jul 2014 01:10:38 GMT

Stephen,

What about a list of those that DO turn off the IS when on a tripod. I get varying answers depending who I talk to at Canon in Australia.

My 100-400L doesn't appear to turn off. When on a tripod, the Focus point slowly wanders around - guess this is the result of feed-back from the sensor?

Re: soft focus problems with 70-200 2.8 lens

ebiggs1 — Wed, 30 Jul 2014 12:59:23 GMT

"My 100-400L doesn't appear to turn off."

It doesn't. More don't that do.

Re: soft focus problems with 70-200 2.8 lens

Stephen — Wed, 30 Jul 2014 14:23:58 GMT

Hi bento!

I've spoken with one of our senior techs very briefly, and he says your lens is one that you do, in fact, have to flip the switch.

He said that while we don't have a list of lenses that automatically turn off, generally speaking it is usually the super telephoto lenses. He mentioned anything smaller than the EF 100-400 L, you'd have to flip the switch.

While I know this might not be the news you were hoping to hear, I hope it helps out some!

Re: soft focus problems with 70-200 2.8 lens

bento2 — Wed, 30 Jul 2014 19:51:21 GMT

Thanks Stephen! Helps out a lot by clearing up the issue.

Re: soft focus problems with 70-200 2.8 lens

ScottyP — Mon, 18 Aug 2014 10:30:01 GMT

I don't think the tripod will help with these images. Even without IS the minimum reciprocal shutter speed on 200mm's is 1/320 second on a crop body. Counting IS you are probably able to handhold reliably at considerably slower speed.

The OP already stated he knows shutter speed is important and offers 1/600th as a starting shutter speed. Since tripods only address camera shake, not subject motion blur, if he is shooting a shutter that fast then camera shake is irrelevant. Birds are fidgety even on foot, so slow shutter tripod work is out of the question due to subject motion blur.