Is this sharp @ f2.8

futureal33

futureal33

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Nick
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Yes
Guys,

Really considering keeping my faulty Sigma f2.8 70-200 because the thing is so damn sharp.
I would sent it to japan to be fixed...and hopefully when it returns the AF would work properly.

Cant work out if Ive got an "extra-ordinary" copy.... or if this sharpness would be just the same with any good performing lens...

To my eyes... this seems exceptionally sharp.

What do you think?

F2.8 only. Manual focus (obviously! because the AF isnt working)

No sharpening, simply imported (with sharpening set to 0) and exported...


IMG_6912 by futureal33, on Flickr


100% by futureal33, on Flickr

Does this seem ultra sharp to you? Or am I just being silly?
 
Ffs, i really dont know what to do.

Its 100% definitely faulty, the AF is inconsistent and it has a rear focus issue. When manually focusing its fantastic however.

These pics are like I say, 100% untouched, simply imported, sharpening (defaults to 25) I then TURNED DOWN to 0, and then clicked export as jpeg. So this is a 100% unsharpened RAW file!

Its bloody sharp

Another example, at F4 this time. Again, no editing at all.


IMG_6928 by futureal33, on Flickr


100 by futureal33, on Flickr


Ps - this is the Mk1 (1999 version) of the Sigma 70-200 EX APO HSM, so its quite ancient now! But all the reviews said the original was the best. But upon speaking to Sigma, they no longer service it in the UK - it would need to go to Japan for a new circuit board to correct the focus. This isnt cheap as you can imagine!
So im really in a difficult position, dont know what to do. I can get a full refund for it...and then buy another (but would it be as good?) or spend another £150+ and wait 8 weeks for it to be sent to Japan and back and then also have the risk that it STILL might not be right on my 5D?

Argh!!
 
scottthehat said:
well if the lens is in good nick otherwise and it does look ruddy sharp and your happry to get it sorted get it done it will be worth it if yoir gonna keep it.
Click to expand...

Scott, the OP is saying about the risk of not still being 100% even after the repair, so he does have a dilemna.

I know I would also be in the same dilemna after seeing the result of this lens.
 
I have this lens, but the NIKON version and I've had to send it to sigma for a new circuit and a few other things.

They ship the circuits over from japan. They have had my lens since the beginning of may and its still not sorted. Think they have tried about 3 different circuits but non of them made it better.
 
Its a shame the Sigma haven't got their QC sorted yet, i have the same lens and had to send it back twice, the second time with my 1ds. This is cracking glass but let down by their QC procedures.

when they asked me to send it back with my camera i was very very dubious about it, I ended up driving to sigma and delivering it myself for my own peace of mind.

M.
 
You seem to have a sharp copy of the lens. Very good. But note that you're cropping from the centre. To play with the big boys, how is edge sharpness?
 
Don't forget you are using a 12MP camera. I'd like to see how it does on a 18MP crop like the 7D, then you can really see how sharp it is at 100%
 
No sharper than I'd expect with this lens, send it to sigma UK for repair and enjoy it when it returns.
 
I'd say it's about as sharp as my Sigma 70-200 f/2.8. Like yours, it's an early edition (not quite as old though, and a cracking sharp lens. Shame about the AF on yours though :(
 
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Cheng said:
You seem to have a sharp copy of the lens. Very good. But note that you're cropping from the centre. To play with the big boys, how is edge sharpness?
Click to expand...

That's the question really. Sure it looks sharp, but all decent lenses are always sharp in the middle. Around the edges is where you may find it falls behind the very best of the rest, especially at lowest f/number - or maybe not ;)

BTW, you can't make a 'super' copy - a lens can never exceed its design spec, though it's quite easy to fall below it.

I think a big contributor to the apparent sharpness in your images is the light. In the first two, there's something reflecting some quite punchy light back to the subject so the image naturally has nice high contrast to start with.
 
The Canon F4L might be as sharp but it is an f4 lens.
1. Do you need f2.8, even every now and then
2. If the Sigma is that sharp at f2.8 can you imagine how sharp it will be stopped down at f4 when you have enough light?!

As for the sharpness it looks like a very good copy, as sharp as the 70-200mm II DG MACRO (latest model before the OS one was released) that I have now and the MK1 non-macro (Same as yours) version that I had last year.

I tried 2 of the other versions (DG and DG macro v1) and found them very soft so it looks like the first and latest versions (and of course the new OS one) are the best.
 
Well due to a sudden and completely unexpected gift yesterday, I am now in ownership of a 5Dmk2! Using MicroAdjust I have dialled in the lens to +20 on micro adjust, and it is still just ever so slightly rear focusing :(

Aimed on the S on the number plate - looks sharpest around the number 7 onwards...although it is a LOT better than it was, and AF is now usable, unlike before where MF was the only option.

Still cant decide to keep it, or not.

Michael, interested in what you say about your 70-200 II DG Macro, as that was the lens I could "swap" this for, for the same price.
Is there any chance you could put up any 100% crop photos at 2.8 unsharpened, to show its sharpness?
Also did it need any microadjust?


IMG_7153 by futureal33, on Flickr


100 by futureal33, on Flickr

Thank you
 
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futureal33 said:
Well due to a sudden and completely unexpected gift yesterday, I am now in ownership of a 5Dmk2! Using MicroAdjust I have dialled in the lens to +20 on micro adjust, and it is still just ever so slightly rear focusing :(

Aimed on the S on the number plate - looks sharpest around the number 7 onwards...although it is a LOT better than it was, and AF is now usable, unlike before where MF was the only option.

Still cant decide to keep it, or not.

<snip>
Click to expand...

Don't worry about it, just wait another week and someone will probably give you a nice new 70-200 Mk2!

That number plate is not a reliable test target though. The car is at an angle, and the number plate is further angled backwards, so you've really no idea what exact spot the camera has chosen to focus on.

Try this - a flat target, square to the camera, at sensible distance (ie not too close). Tripod. Shoot pictures right through the microadjust range at increments of 5, defocusing between each shot. Flick through them on the LCD on max zoom view and see which one is sharpest. Fine tune based around that setting.

You might find that it's slightly different at different focal lengths, and you might also find it's not 100% consistent.
 
I might have got my knickers in a twist here but if you add + MA doest that move focus foward? If so bring it back to +15 as it's back focusing now, well to me at least when viewed on my phone.
 
Richard,

Thanks for the tip - just done that test and here's the results.. Seem it is still rear focussing.

The sharpest shot out of (-20 through to +20 was definitely the -20 one) it got worse as I dropped below -20

So this is a shot showing -20 vs manual focus through live view.

AutoFocus

100af by futureal33, on Flickr

Manual Focus

100mf by futureal33, on Flickr
 
Quote:
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:bonk:
 
The particular point Im referring to is the hair towards the back left of the photo being sharp... which isnt on the same focal plane as her eyes which are the focus point.

How can both her eyes and the hair at the back of her head be sharp...but the hair inbetween is blurred?


IMG_7196 by futureal33, on Flickr


cropp by futureal33, on Flickr

Any ideas??
 
futureal33 said:
The particular point Im referring to is the hair towards the back left of the photo being sharp... which isnt on the same focal plane as her eyes which are the focus point.

How can both her eyes and the hair at the back of her head be sharp...but the hair inbetween is blurred?

<snip>

Any ideas??
Click to expand...

The image is a tad back focused, but it's a trick of the light and the bright sharp hair on the left is actually on the focus plane. It's confused by the blown area which separates it from the rest of the hair. No such confusion on the right hand side.
 
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Richard,

Do you think this amount of back-focus would show up in print (upto A3 size)?

Cant make my mind up whether to keep this lens, and use AF knowing it will be slightly back focussed, or to use a tiny bit of manual focus overide adjustment (it literally needs a fraction of a turn to the right on the focus to bring sharp) or to sell it and get another..

It just seems so sharp, im worried that I wouldnt get another one as good?

My worries came about yesterday when I tried a Canon F4L IS lens (which is supposed to be THE sharpest telephoto lens ever) and no kidding, it wasnt as sharp as this Sigma... it wasnt bad by any means, but not amazing either.

Here is a sample photo from a Canon F4L IS lens: F4, ISO250, 1/640sec


IMG_7044 by futureal33, on Flickr


100 by futureal33, on Flickr



As you can, it isnt BAD but its definitely not in the same league as this Sigma!!
 
futureal33 said:
Richard,

Do you think this amount of back-focus would show up in print (upto A3 size)?

Cant make my mind up whether to keep this lens, and use AF knowing it will be slightly back focussed, or to use a tiny bit of manual focus overide adjustment (it literally needs a fraction of a turn to the right on the focus to bring sharp) or to sell it and get another..

It just seems so sharp, im worried that I wouldnt get another one as good?

My worries came about yesterday when I tried a Canon F4L IS lens (which is supposed to be THE sharpest telephoto lens ever) and no kidding, it wasnt as sharp as this Sigma... it wasnt bad by any means, but not amazing either.

Here is a sample photo from a Canon F4L IS lens: F4, ISO250, 1/640sec

<snip>

As you can, it isnt BAD but its definitely not in the same league as this Sigma!!
Click to expand...

1) You will, of course, notice any degree of incorrect focus when shooting at f/2.8.
2) If you think you can correct it with a nudge, good luck to you :eek:
3) I find it hard to believe your lens is actually sharper than a Canon 70-200L 4 IS, though they could be as close as makes no odds. You need to shoot the same subject, same camera, identical everything side by side to make a judgement between two lenses of that kind of quality. And there's more to a lens than just sharpness. It doesn't matter how sharp it is if you can't get it in focus ;) not to mention flare resistance, IS, and mechanical/build considerations.
4) Since lady luck has smiled on you big time with the wonderful gift of a fantastic new 5D2, do the decent thing and sell whatever you have to and get a Canon 70-200L 2.8 IS Mk2. Then you can stop worrying - that is one amazing lens and the best 70-200 on the planet by some margin (y)
 
Thought Id post this - straight out of camera (RAW converted to Jpeg with no sharpening/PPing at all)

Canon F4L IS @ 150mm F4


IMG_7402 by futureal33, on Flickr


100F4 by futureal33, on Flickr

Id say its sharper than the Sigma with hindsight, although, bearing in mind the Sigma is at f2.8 I dont think it did bad at all.
 
The Sigma really was very impressive, if it had focussed correctly I would have kept it.

But I am going a slightly different route now... Canon F4L IS for my telephoto work (no portraiture) and a 135 F2L for my portraits OR a Canon 200mm F2.8L - havent quite made my mind up yet.. but I am enjoying the thought process of deciding

All the best, I hope this helps anyone in my position, and wouldnt completely recommend the Sigma provided you get a fully functional copy!!
 
futureal33 said:
Thought Id post this - straight out of camera (RAW converted to Jpeg with no sharpening/PPing at all)

Canon F4L IS @ 150mm F4


IMG_7402 by futureal33, on Flickr


100F4 by futureal33, on Flickr

Id say its sharper than the Sigma with hindsight, although, bearing in mind the Sigma is at f2.8 I dont think it did bad at all.
Click to expand...

Now that looks good, especially on a 5D2 (y) As I think someone told you it would be :D

IMHO the f/4 IS is the thinking man's choice, such a nice lens to use. The Mk2 2.8 wasn't available when I got mine, and every now and then I wish I had that wonderful zoom, or a 135L 2 like you to use alongside the f/4, but when I want bokeh I just move the subject away from the backgound and shoot at 200mm f/4 and the feeling goes away. And both my bag and my wallet are all the better for it.

That's not quite the same as the shallow DoF you get at f/2.8 or f/2 for sure, but the effect looks pretty similar in terms of a big blown bokeh background.

BTW, how long have you known Tom Jones?
 
futureal33 said:
Hahah! I think you have just made or ruined my Dads evening! Im not sure if he was happy or sad lol.

The 200mm F2.8L is very affordable, I watched one the end the other night on eBay for £390!! Thats pretty cheap for a fixed 200mm prime...

Certainly very impressed with this 70-200 F4L IS though for now!!
Click to expand...

I would live with it for a while and see how you get on. It's always a compromise and while I keep looking, TBH I've always found a way around with the 70-200L 4 IS - and a smile.

If there's a choice, I find 200mm is a bit long for portraits and for £300 new, the (forgotten) 100mm f/2 is a thought? Another compromise LOL ;)
 
I told you it was a good copy!

Oh and I can't recommend the 135 enough by the way, it's magical
 
futureal33 said:
Richard,

Id never even heard of the 100mm f2 but the reivews for it seems excellent!
Thanks for pointing that out! Have you ever used one, any experience etc?

My god, it just got more complicated!! Thanks a lot lol
Click to expand...

Never heard of it? You'll be saying you've never heard of the new 70-200 f/4 Mk2 next! It's much better than the one you've got ;)

No, I've never used a 100 2, but I have tried the 85 1.8 which is almost identical, and that's an ackowledged little bargain - great on a cropper.

But if you have pixel peeping tendencies neither of those is quite in the 135L 2 league when used wide open. Compare them on TheDigitalPicture.com
 
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