Is there a learning curve when shooting 200mm at f/2.8?

Hey all,


Picked up a Sigma 70-200 f/2.8 off Adverts. Read up on it extensively. Apparently a fair few "bad copies" out there. Front/Back focusing a common issue, etc.

Anyway, much like when you read a medical book and think you've got every disase in it, I used the lens repeatedly in sturdy environments, focusing manually and auto on static items, etc. and I'm fairly sure my version of the lens is a happy camper in the focus department.


So, I go out to take a few photos of a person, and I get them to stand still. I go to f/2.8 and 200mm, focus automatically, hand held, but the person is staying still, and I burst shoot about five images. I alter my focus manually, fire off another burst, focus automatically, rinse repeat.


I get home, and a vast majority of the shots are out of focus. In about 20 images, I'm lucky to get two or three in focus.


So I'm wondering, am I doing something wrong here? Is the depth of field when shooting at those settings so shallow, that my body moving/shaking, etc. is able to cause my focus spot to be moved backwards or forwards enough to blur my subjects face?


I've been trying to use the lens as much as I can in an attempt to get used to it and become more familiar with it, but I'm still having focus issues.


As far as I know, if I were shooting football, etc. and the players were a good distance away, I'd have a larger area of focus than when doing portraiture (because my model is only a few feet away)? Is it possible this could be a reality? Or is that just me being poorly informed and trying to figure out in my head where I'm going wrong?


Am I best to give up shooting at 2.8 for closer subjects, and go with f/4 or f/5.6, or is it like anything else, where you can get used to f/2.8 and it becomes less and less of a luck issue?


Or am I just crap?

challengemaster

Whats your shutter speed for the shots, that'll be a good indicator

challengemaster

challengemaster wrote: »

Whats your shutter speed for the shots, that'll be a good indicator

I really don't think it's blur. I did (my first) portrait session and kept to the flash sync speed of 1/250th of a second a few weeks ago. Someone mentioned shutter speed to me, so I was aware of my shutter speed when I did the Drogheda Parade then, without flash on the body, and I tried to keep it at a slowest speed of 1/400 or thereabouts (Note; I expected out of focus shots in the parade as everyone was moving around quite fast, as was I, but for people who are posing or barely moving, it's been bugging me).


I usually delete every shot that doesn't look spot on, so unfortunately, I don't have any examples I can post up to show the images I'm unhappy with.

Actually, I took a quick flick through my PC and found this image which shows my issue.







You should be able to view the full size version on my Pix, but incase it's restricted at all, here's a direct link;

http://photos3.media.pix.ie/6A/5F/6A5F542FB54A458BA2435ABD5F8B666B-0000333410-0002229441-03504L-8D87796A2EA24D32942A35F0C979ACBF.jpg



Now, that's a RAW file, opened in Adobe Camera RAW, saved as a Jpeg and uploaded, so it hasn't had any editing or such done. To be honest, I haven't a clue where the focus is supposed to be in that image.

I took a few photos of a woman prior to shooting that girl, and a few were out of focus, so i was aware of the problem when shooting that girl. So I made sure that every shot was in focus before pressing the shutter. That said, I don't know if i focused manually or using auto.


That was shot at 104mm, f/2.8, ISO 200 and 1/250.

CabanSail

What distance were you from the subject?

I have put the figures into my Field Calculator, assuming it was 6m the DoF is 40cm

If it was 4m the DoF drops to 10cm.

Go away with your meters! I was about 8-10 feet! :P


That's entirely guess work. I can't really remember, but if I filled the frame with her like that, at 104mm, then I'd say 8-10 foot is accurate enough. According to Google, 9 foot is almost 3 meters (2.7 meters to be precise, I believe). Even though we're dealing with incredibly shallow depths here, I still can't look at that image and see where I focused. I must have focused in front of her nose, in order to have her so softly out of focus, but not completely blurred!?

I can't see any sharp hair on her head, so I'm guessing I didn't go backwards (I usually aim for the eye).


Is it possible that just natural human body movement can account for missing the focus with such a shallow depth of field?


Also.. where are you getting these calculators from, Caban?



EDIT;

Quick google brought up this online calculator;

http://www.dofmaster.com/dofjs.html


Using 2.8 at 104mm and a subject distance of 10 foot, it reckons my depth of field is 0.29 foot, which converts to 8.8cm using an online converter.

That seems that I should have been easily able to get her nose/eyes in focus though...?

CabanSail

I am using my Field Calculator App.

When I change it over to the antiquated Feet & Inches it gives 4" at 10' distance.

pete4130

My opinion is its a Sigma issue. I've said many times about poor results form the Sigma 70-200 2.8 and the Sigma 24-70 2.8 and this is some sort of proof.

I used mine the same way, stationary object, focused properly, fast shutter speeds and poor results

gloobag

Does this lens have any form of stabilization built in? IS/VR, don't know what Sigma call their version. You could try turning that off if it does. If you have a decent shutter speed it won't really be of any benefit and can sometimes cause similar issues to yours (well, it does on my Canon 70-200 anyways :rolleyes:).

Thecageyone

The newer version has OS but its just as pricey as the canon/nikon offerings because of it.

I'm surprised nobody has yet suggested not to shoot in burst mode for portraiture. I never do, it's too hit and miss and there's always the possibility that you're moving the camera during that burst, even just slightly. Better to compose for each shot, take all the time you need. Sony depend on luck. Your subject may appear to be still but even blinking and alight movements might throw the perfect focus off.

I'm interested in this lens too, as the nikon one is way out of my price range for now.

pete4130

Again, I can't iterate enough how poor this lens performed for me. Sold within a week of getting it. Couldn't wait to get rid of it. Luckily a friend brought it back from NYC so I only lost about €25 on it. If your getting these problems on a crop sensor with smaller image circle I'd hate to think how it would perform full frame.

Yeah I am biased against most Sigma lenses but I've seriously had major troubles with this one.

TCO, I know we've had our disagreements before but I'd suggest to avoid it. Spare yourself the pain and the money. Nikon 80-200mm 2.8's are cheaper than the Sigma 70-200 2.8 and are far superior. I've got the latest EF-D twin ring version (which is reportedly the LEAST sharp version of the lens) and mine is super sharp. A friend bought one second hand that had a dented barrel where the filter attached, dents and scratches all over. Before he bought it we did a sharpness comparison test...same focal length (200mm) at 2.8 at minimum focus distance and his version was ever so slightly sharper than my version even though it had been bounced around by a journo. Testament to quality!

The older push/pull versions are meant to be even sharper than the twin ring version I have, a bit heavier too but cheaper. For the focal range it can't be beaten on image quality or value for money. It's pretty much on par with image quality compared to the Nikon 70-200 2.8 (mki....which was rumoured to be built specifically for crop sensor cameras and doesn't perform as well on full frame as it could....only rumoured though) and lacks VR and costs a hell of a lot less.

here's one for €850 with the hood (which doesnt come as standard but its about €5 on ebay) which is in or around (maybe cheaper than) the price of a new Sigma 70-200 2.8 ii lens. I know what I'd spend my money on.

http://www.adverts.ie/lenses/nikon-af-s-80-200mm-f2-8-for-sale/475508

I was really lucky and managed to get my Nikon 80-200 2.8 through adverts for €450 about 3 or 4 years ago in almost mint condition. The biggest thing I can fault my 80-200 with its the switch for AF to M focus doesn't lock in place securely but its a minor minor niggle.


EDIT: The lens I've linked to is actually newer than my AF-D version and is the latest AF-S version which again is slightly sharper than my version and focuses nearly almost as fast as the 70-200 2.8 AF-S, so €850 is a really good price for it!

Thecageyone

I know you mean what you say, but I have read good reviews on the sigma. I'd happily take any of them to be honest but I would be very annoyed if I got a bad copy. I have an old push pull manual lens, a 70-210, but find it very fiddly to handle. Of course if it had af it would be a lot easier. Not much hope capturing a bird in flight for example with my current one.

FoxT

You can test the focus on your lens easily.....

Tape a measuring tape to a stick, lean it against a wall, camera on tripod, compare manual to auto.






Backstory: I bought a canon 70-200 f/2.8 last year & thought it very soft. Did this test, saw the AF was off. Sent lens to Fixation in the UK, and, oddly, they needed the camera as well ( this surprised me as my other lenses worked fine, including a 50 f/1.4) got it all sorted for about eu120 or so, plus the reassurance that my lens was perfect as well.

And yes, I find that using this lens takes practice. DOF is very shallow even at distances of up to say 20 feet , where with shorted lenses you will get away with it. Also, I found that after spending that much money on a lens I was a bit paranoid about it initially - was chimping everything to the nth degree.

And, finally, At the resolution posted, your photo seems OK. It looks sharp from just behind her eyes to the 2nd or 3rd knuckle on her hand. I'd say you aren't too far off.

- FoxT

pete4130

Thecageyone wrote: »

I know you mean what you say, but I have read good reviews on the sigma. I'd happily take any of them to be honest but I would be very annoyed if I got a bad copy. I have an old push pull manual lens, a 70-210, but find it very fiddly to handle. Of course if it had af it would be a lot easier. Not much hope capturing a bird in flight for example with my current one.

Buy cheap buy twice. The push pulls are amazing if you can forgive some zoom creep. Gladly take a push/pull over a Sigma in a heartbeat. It's still an AF Nikon pro lens and you hear so often than good glass is always good glass. From my experience Sigma glass is mediocre at best. My point being, why pay so much on a gamble for something that could be utter crap!?

Adrian.Sadlier

I use a Nikon f2.8 VRII. Its sooo sharp! Well worth the money - the lens will last longer than me. This shot was taken at 180mm at 1/160 - I think VR was off. Post processed in CS3 to remove noise which softened it a little - still quite sharp

Thecageyone

I'm not sigma's biggest fan either. I've had a few of their lenses and never really liked any of them. For third party I prefer tamron. Of course I'd go nikon all the way if the funds allowed.

I had a chance to buy a sigma 105mm macro lens recently, but after reading tonnes of reviews I went for a 60mm nikon instead. I may get stung by wasps afew times because of this, but I went with reliable over focus distance. The nikon was also cheaper and I know I could sell it in a few months for what I paid. Sigma lenses lose value rapidly.

The old push pull manual lens I have does have nice enough glass. I've gotten better results with it than any cheap modern zoom I've tried, and it cost me less than €100

I'm wondering, OP, did you happen to have the lens in it's macro mode when shooting? Just a thought. Some lenses with macro capabilities have to be switched between modes. Macro focus/infinity.

pete4130

The funny thing is, I had the Sigma 105 2.8 macro and prefer it to the Nikon in some ways and not others. It's probably one of the Sigma lenses I'd rate somewhat highly.

My end point being, if your going to get a 70-200 2.8 lens and with nikon and don't want to break the bank, wait for an 80-200 2.8 to come up. It's worth it.
2 years ago I almost traded "up" for a Nikon 70-200 2.8 VR but before I did I realised I was going to be paying an extra €1100 for a lens that was marginally better than one I had so stuck with it. My 80-200 is seriously the best value lens I've bought. I can't see myself getting rid of it soon at all. If I was home I'd lend you it so you could see what I mean!

Thecageyone

Aye, sure we could have a pint and go shooting, see who ends up in the river

I'll look into that 80-200 2.8 for sure. Only ever hears about it, never read up on it.

As for the macro, delighted with the 60mm, I've already done portraits, insect close ups, some playful water shots and the obligatory flower macros with it. I would safely say it's the sharpest lens I've ever used. You do need to get close for true 1:1 but I don't mind getting down and dirty. And I did have to search hard for any negatives on either it or the sigma. Resale value is important to me right now though, as I usually need to sell one lens to buy another. Kissed my 85mm goodbye for this one. As I'm thinking I will have me a 70-200 2.8 sometime

mehfesto

pete4130 wrote: »

The funny thing is, I had the Sigma 105 2.8 macro and prefer it to the Nikon in some ways and not others. It's probably one of the Sigma lenses I'd rate somewhat highly.

My end point being, if your going to get a 70-200 2.8 lens and with nikon and don't want to break the bank, wait for an 80-200 2.8 to come up. It's worth it.
2 years ago I almost traded "up" for a Nikon 70-200 2.8 VR but before I did I realised I was going to be paying an extra €1100 for a lens that was marginally better than one I had so stuck with it. My 80-200 is seriously the best value lens I've bought. I can't see myself getting rid of it soon at all. If I was home I'd lend you it so you could see what I mean!

I'm in the market for one now myself. Does anyone know places in Dublin that carry them - are they common lenses to be stocked? what's the going rate 2nd had?

Thecageyone

80-200? There's one up on adverts currently, but looks like someone has made the right offer:

http://www.adverts.ie/lenses/nikon-af-s-80-200mm-f2-8-for-sale/475508?page=2#comments

Looks to be going for €780

So... Anyway...


As per the second sentence in the OP;

"Anyway, much like when you read a medical book and think you've got every disase in it, I used the lens repeatedly in sturdy environments, focusing manually and auto on static items, etc. and I'm fairly sure my version of the lens is a happy camper in the focus department."


So I don't believe it's a focus issue. I've photographed stuff in and around my house. Static objects (cups/plates/etc.) at 2.8 and have no issues. It just seems to be when I'm out and about.

Thecageyone

So ... Anyway ... I think there's some good tips in there if you read the posts

From post 10 onwards, with the exception of FoxT, it seems to just be talking about other lenses, and you asking about the macro mode. :P

I don't mind discussion of that kinda stuff, but I was delighted when I seen to many replies to the thread before I clicked into it. I thought I'd definitely have the issues sorted after reading it all

Anyway... The lens only is called Macro because it can focus closely (about a foot and a half or so away) relative to other telephotos. There's no actual macro switch, only an AF/MF focus one.


FoxT, did they charge you €120 for looking at the lens and you had to pay postage etc. on top of that? or was the €120 including postage to and from them etc.?

Thecageyone

Deleted User wrote: »

From post 10 onwards, with the exception of FoxT, it seems to just be talking about other lenses, and you asking about the macro mode. :P

there was a valid reason for asking on that point, but you've answered it just now.

I know my ancient Vivitar zoom has to be twisted into "macro mode" and the focusing drastically changes.

Thecageyone

Thecageyone wrote: »

there was a valid reason for asking on that point, but you've answered it just now.

Oh, I wasn't saying there wasn't a valid reason for asking. If it had a macro switch, then it would have been very important, of course.

Thecageyone

Don't get me wrong, I'm very interested in your issue here. I've been eying that particular lens for a while. If I had the money on me I'd be very tempted to purchase one. But now Pete, and your issue, have put me off, maybe there is a flaw with this model?

Well see, here's the thing; I don't really know if it's a problem with the lens.

Here's an album I made on Pizx with a few photos i took in the last ten minutes or so. It's pretty dark in the rooms i was in, so ISO is 3200, unfortuantely. Anyway, centre focus point was used, and all were shot at 200mm and 2.8;

http://pix.ie/chokeslamcena/album/405314


The focus doesn't seem to have any trouble here. (Camera was set to one shot and single focus, so no AI Servo or burst shooting). Apologies for the darkness, but I felt that if I edited them at all it'd eliminate the point.

Focus points on the images were;

1. My knuckle
2. Pattern on Frame
3. "No"
4. Second highest steel loop
5. Left side of the bolt
6. "4GB"
7. "SmackDown!" logo

(again, all using the centre focus point). You should be able to view all those photos full size.

I probably should've used a flash gun but i wasn't thinking. So I think it's just down to me.

Thecageyone

Considering the dark conditions you shot in, focus seems to be pretty much where you wanted it to be on those shots. Unless my eyes are completely gone!

That's what I mean. I can seem th nail the focus when I'm in here and take my time making sure it's spot on.

However, in the real world, well, the picture on page one I posted, i get that a lot.

FoxT

@KKV -

cost breakdown was approx:

Ship camera & lens to UK - EU 30
Invoice from fixation - GBP139 = EU160 (This included postage)

This included replacing the shutter button on the camera though (known 40D issue, & mine was going....) which was GBP 10 for parts & wild guess of 30-40 for labour. So I think the focus on its own would be about eu120-140 incl postage to & from.

Your focus looks fine to me at web resolution, but the one I posted doesnt look too bad, either - so I cannot really tell.

I find on the 40D - If you use backbutton AF & AI SERVO the shutter will fire regardless of whether the lens has focused fully or not. Whereas in 1-shot mode the 40D will always focus first, beep & then fire. Your own camera may exhibit similar behaviour - it took me a while to figure that one out myself!

Cheers, FoxT

PopeBuckfastXVI

May or may not be relevant?

http://www.canonrumors.com/tech-articles/this-lens-is-soft-and-other-myths/

pete4130

I hate to break it to you. You have a sh1t lens. you're doing nothing wrong other than using a sh1t lens.


EDIT:

Tomorrow I'll try find time to shoot some 200mm 2.8 shots at 1/40th or 1/50th at min focusing distance, hand held ( so the 80-200 is at its worst) and you'll realise what I mean when I say the Sigma is terrible.

If so many people stopped buying Sigma then they might do something about their QC.

pete4130

Here's a shot at 200mm, 2.8 at minimum focusing distance, iso 1600 and about 1/250th or 1/320th handheld





and here's a 100% crop of the fingers which is fairly sharp considering closest focus distance, handheld and relatively slow shutter speed for the focal length and the lens wide open. No PP on these other than reszing the 1st image and a 100% crop for the 2nd image.

You really don't like this lens, do you Pete? :P
What body are you using, Pete? Some bodies handly noise better than others. The photos below were on a 20D.


Right, I'm always prepared to accept there's something wrong with the lens. I have strongly felt that the lens was grand, though, and that it was a "user error", so to speak.


I'm not sure how you determined that that was the closest focusing distance, so what I did, was manually focus the lens to it's minimum, and move myself back and forth from a bottle of face cream or something that's on the desk across from me.

So I moved back and forth, focusing my eye on the word "it" on the top right;


(ISO 1600, f/2.8, 1/320th)





Full size can be viewed on Pix, but here's a 100% crop anyway;





Now, at it's closest focusing distance, and at 2.8, handheld at 1/320, I don't think that's too bad at all. I can live with that.


However; I did find an issue with the lens.


I sellotaped one half of a measuring tape to the floor and the other side to the room door. Sat on a chair over the bit sellotaped to the floor and focused on the number 3 that appears under 64 (in red).

The focus point wasn't at it's minimum focus distance, though. The number 3 I focused on was about two and a half-three feet away.


Manually focused, I get this;





100%;





However, when left to it's own devices on Auto, I get this;





100%:






Now, judging by the measuring tape photographs, the lens does seem to front focus, though by less than an inch.

I've been told I should wear glasses, though, so it could also be that my eyesight isn't the best in the world either (both images seem to jump around the 3, but neither land exactly on it).


All these images, again, were handheld at 1600 ISO, 1/320th and f/2.8.

If the lens is front-focusing by less than an inch, when something is three feet away, I could understand that as a reason for my shots to be out of focus if I were a macro buff. However, as the photo I posted on Page 1 was taken from about 10 feet away, I don't think that even a small bit of front focusing could cause the issue I'm having?

pete4130

I've just had bad experiences with the lens, or a copy I had and it really annoyed me so I am biased against them.

I'm using a D3 body so its going to handle noise better than a 20D. Being full frame its going to use a larger image circle of the lens and show any distortions moreso than a crop body.

With regards to your test and front focusing, it could be an issue of poor lighting that the lens can't lock on to what you want it to focus on. It might not be front focusing? There are charts you can download and print out to see what your lens is doing and use a tripod too so your camera can't move.

When you've focused on the word "it" the lens seems to be acceptably sharp for handheld, manual focused at 1600 iso tbh. If it is a front focusing issue then you would have to get the lens sent off for calibration. Others know more about this if its free or not and where to send it.

Apologies if I was harsh on the lens saying it was sh1t....I've still got a bad taste in my mouth from the copy I had!

Don't apologise at all, Pete. If it weren't for you posting in this thread, I'd have never bothered taking out the measuring tape, or focusing on the word "it", etc. so I wouldn't have found my possible front-focusing.


If someone who openly admits to disliking the lens and it's makers can say that my copy of the lens isn't too bad, then that's a good thing, because it means that, although it's possible i may have unearthed a front focusing issue with the lens, I still haven't figured out my original problem and so I can continue on to try and figure out what's causing aggro.


Boards would be a pretty crap place if everyone agreed with each other.


that said, though, I've never had a 2.8 70-200 before. I've only got this one a few weeks and I haven't used it that much at all, so I'm not sure if there's something I'm missing or not but I'm clearly still having issues with it, as per the picture I posted on the first page.


I have a 1D Mark 2 here, but the focus screen in it doesn't have a centre focus point. I was gonna use that to do my tests, as the shutter button requires less force pressed upon it, but I wasn't confident in it's focusing ability without a centre point visible to me.

FoxT

Where is zerohamster when you need him? I dont know him at all but he seems helpful & I expect would be happy to respond to a PM & give advice..

If you are out by 1 cm at say 1m distance, how much are you off by at say 2m,3m, etc? I have no idea. Might be worth a try.

-FoxT