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05-01-2010, 09:03 PM   #91
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QuoteOriginally posted by Marc Sabatella Quote
How about then posting the piture howing the whole frame, as well as a 100% crop?




Huh? Are you saying the hair was only 1cm from the camera? Surely the lens can't focus anywhere *near* that close?



"Sharp" is a relative term. It should be "pretty sharp" at f/2.8, sure - but not *as* sharp as stopped down. Looking at crops will show the difference, and as far as I can tell, that's exactly what you are seeing here.



I'd say until you post examples that really make it clear, it's going to be impossible for anyone to say for sure. but right now my money is on the lens being perfectly fine.

showing the whole frame and the focused crop portion of the image would be better in evaluating the image.

I'm not sure what he meant by that but it seems like he just went too far closer than what the lens' minimum focusing distance is capable of, thus showing an out of focus image. if not, maybe he was referring to the DOF distance of a focus portion to that of an out of focus region. I would however say that a 1cm distance is close enough distance between the shallow DOF background and the portion in focus, to be out of focused or show misfocused even and especially at f/2.8 wide open. this is more obvious in close up shots.

I do agree that a few more examples should be shown and several tests as well. I wouldn't recommend doing the same testing procedure over and over again as there might be a possibility of testing procedure error.


Last edited by Pentaxor; 05-01-2010 at 09:25 PM.
05-02-2010, 05:44 PM   #92
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the 1cm comment was in response to the previous suggestion that maybe my subject was outside the DOF. I stated that I focused on the hair and that from the foreground of the hair to the back of the strand is 1cm. Not that I was 1cm from the subject.

Here are two pictures from today. Again the 2.8 is not as sharp as the 5.6. In fact instantly looking at the 2.8 I feel like my eyes are trying to focus because it just doesn't look rite to my eyes. I shot around this morning and I get the same visible difference. And I pose this to you. Why even buy a "fast lens" if you just accept that pictures at 2.8 won't be sharp.
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05-02-2010, 06:33 PM   #93
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QuoteOriginally posted by smcook99 Quote
the 1cm comment was in response to the previous suggestion that maybe my subject was outside the DOF. I stated that I focused on the hair and that from the foreground of the hair to the back of the strand is 1cm. Not that I was 1cm from the subject.

Here are two pictures from today. Again the 2.8 is not as sharp as the 5.6. In fact instantly looking at the 2.8 I feel like my eyes are trying to focus because it just doesn't look rite to my eyes. I shot around this morning and I get the same visible difference. And I pose this to you. Why even buy a "fast lens" if you just accept that pictures at 2.8 won't be sharp.

are these RAW or Jpeg? have you tried adjusting the custom image sharpness level on the camera? comparing these shots from your first set of photos (uncalibrated), there is an easily noticeable degree/level of improvement in sharpness. not as horrible as the first shots.

1st photo:


latest photo:

Last edited by Pentaxor; 05-02-2010 at 06:40 PM.
05-02-2010, 07:33 PM   #94
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the crops were from RAW the full's are JPEGs off the camera. I was trying to get the post out before my battery died. I absolutely agree that the lens has improved. I guess I just expected equal sharpness through the whole range of the aperture.

05-02-2010, 09:48 PM   #95
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QuoteQuote:
smcook99: Here are two pictures from today. Again the 2.8 is not as sharp as the 5.6. In fact instantly looking at the 2.8 I feel like my eyes are trying to focus because it just doesn't look rite to my eyes. I shot around this morning and I get the same visible difference. And I pose this to you. Why even buy a "fast lens" if you just accept that pictures at 2.8 won't be sharp.
2.8 is never going to be as sharp as 5.6, no matter who repairs the lens--these are the facts of life. However, when right, I assure you this lens produces plenty sharp enough images at 2.8. Some people like larger apertures, not only for lower light conditions, but also for isolating the subject. For example, look at the 2 non-cropped shots of your son. Note the separation of him from the background in the 2.8 shot vs the 5.6 shot.

BTW, what are your in-camera settings at for sharpness? Also, you are under-exposing some--about 2/3rds more of a stop to the right will get you much improved pics.

QuoteQuote:
smcook99 the crops were from RAW the full's are JPEGs off the camera. I was trying to get the post out before my battery died.
Are you saying you shot Raw+Jpg for these two shots?

QuoteQuote:
smcook99: I absolutely agree that the lens has improved. I guess I just expected equal sharpness through the whole range of the aperture.
Certainly different users have different expectations, but yours are not reasonable. Lenses perform differently at different apertures and thank God this is so, otherwise boredom would set in quickly. One of the best mysteries to unravel in photography is the varying performance of lenses at different apertures. BTW, for portraits, the shallower DOF of the Tammy 2.8 is a very desirable thing.

Try some more shooting, with better exposed shots, and with your in-camera sharpness turned up a notch or 2. Also, for comparison, you may want to take some shots with manual focus.

Up to this point, I would say your Tamron can do better for you, but I am not ready to say it is the Tamron's fault, not just yet.
05-02-2010, 10:29 PM   #96
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QuoteOriginally posted by smcook99 Quote
the crops were from RAW the full's are JPEGs off the camera. I was trying to get the post out before my battery died. I absolutely agree that the lens has improved. I guess I just expected equal sharpness through the whole range of the aperture.
you have to stop down inorder to get the best out of that lens or simply saying finding out it's sweet spot.

I think you just need to let the lens to warm up on you. probably do some in-camera tweaking like AF adjustments, sharpness and contrast. then do more shooting. from what I could see, the lens is already in the ok or acceptable sharpness wide open category. probably a few tweaks would solve that problem or seal the deal finally.
05-03-2010, 06:00 AM   #97
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I shoot in RAW+jpeg. I only use the JPEGs for quick browsing when choosing which shots are worth PostProcessing and which I'll just archive. I was under the impression the sharpness setting in the camera is only for JPEGs and doesn't affect the RAW file?

I shoot all my portraits in 2.8 because I like the subject to POP out which is why I was so miffed when 2.8 came back soft. I have a 20 year old manual Tamron that does 3.6 at 70mm and it's great and the shots are great but I would never waste my time trying to get my son on the playground with a manual. Actually I've done it and I can get some shots, but I come back with 1/5 the amount I'd have with an AF lens.

I shoot in Aperture priority when I have an AF lens attached because i want to maintain as shallow a depth of field as possible. I didn't expose that shot any more because the preview was already reading on the edge of blowout. it was incredibly bright yesterday and I was at 2.8. When I processed that shot later for what I call a "keeper" version, I used the fill light adjustment and evened it out nicely. I would have had my fill flash on normally but yesterday was just about testing the lens.

I'll shoot around with it some more and see if I can find maybe just a small combination of zoom and aperture to avoid, versus the first time I had it when there was only a small combination that worked. That shot above I believe was at 70mm, I have another at 2.8 50mm that is crisp which is what I was expecting. I guess the reason I'm still irked is because when I can look at the camera's LCD and see softness without ever having to get it to a computer; well I feel for $450 I shouldn't. Is it possible that my 2.8 is crisp upto a certain zoom?


As I think about it. Had I not originally had such an issue with the lens I probably wouldn't have thought twice about the quality of the pictures I just took; but because I know the lens had issues I'm now looking too hard for that softness perhaps.

Last edited by smcook99; 05-03-2010 at 10:34 AM.
05-03-2010, 10:43 PM   #98
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QuoteQuote:
smcook99 I shoot in RAW+jpeg. I only use the JPEGs for quick browsing when choosing which shots are worth PostProcessing and which I'll just archive. I was under the impression the sharpness setting in the camera is only for JPEGs and doesn't affect the RAW file?

I shoot all my portraits in 2.8 because I like the subject to POP out which is why I was so miffed when 2.8 came back soft. I have a 20 year old manual Tamron that does 3.6 at 70mm and it's great and the shots are great but I would never waste my time trying to get my son on the playground with a manual. Actually I've done it and I can get some shots, but I come back with 1/5 the amount I'd have with an AF lens.

I shoot in Aperture priority when I have an AF lens attached because i want to maintain as shallow a depth of field as possible. I didn't expose that shot any more because the preview was already reading on the edge of blowout. it was incredibly bright yesterday and I was at 2.8. When I processed that shot later for what I call a "keeper" version, I used the fill light adjustment and evened it out nicely. I would have had my fill flash on normally but yesterday was just about testing the lens.

I'll shoot around with it some more and see if I can find maybe just a small combination of zoom and aperture to avoid, versus the first time I had it when there was only a small combination that worked. That shot above I believe was at 70mm, I have another at 2.8 50mm that is crisp which is what I was expecting. I guess the reason I'm still irked is because when I can look at the camera's LCD and see softness without ever having to get it to a computer; well I feel for $450 I shouldn't. Is it possible that my 2.8 is crisp upto a certain zoom?


As I think about it. Had I not originally had such an issue with the lens I probably wouldn't have thought twice about the quality of the pictures I just took; but because I know the lens had issues I'm now looking too hard for that softness perhaps.
I'll try this question again: What are your sharpness settings at in camera?

QuoteQuote:
smcook99 the crops were from RAW the full's are JPEGs off the camera.
I would be consistent when posting: either take the crops & non-crops from the Raw, or take the crops & non-crops from the Jpg. But, for comparison here, it makes no sense to mix the shots up, Raw & Jpg, particularly since the Jpg is altered by the in-camera settings. Does this make sense?

The only blown highlights in those shots, and there are only a tiny % of blown pixels, is on your son's left shirt collar, since the light is coming in from his left. His short collar is not your subject, but your son is. If you are not going to fill flash, then you need to expose more to the right in order to get the best IQ--it is that simple.

I think the lens is fine, but do agree with Pentaxor that you need to practice some more with it. Try for a couple of weeks, then post some new shots here for us.

05-04-2010, 09:15 PM   #99
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QuoteOriginally posted by smcook99 Quote
I shoot in RAW+jpeg. I only use the JPEGs for quick browsing when choosing which shots are worth PostProcessing and which I'll just archive. I was under the impression the sharpness setting in the camera is only for JPEGs and doesn't affect the RAW file?
Doesn't affect the file, but does often affect the amount of sharpening your RAW processing program chooses to apply.
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