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07-13-2011, 01:14 PM   #121
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QuoteOriginally posted by mkvlln Quote
...brought it out last week to a gig. It's performance was really really disappointing. The flares are unimaginable, to a point where I felt like throwing the lens immediately and use my Pentax SMC lens (which is by far leagues ahead of Tamron in terms of flares).
This is imo the Tamron's biggest weakness. Mine never looked anywhere as bad as yours though. Most of the time my flares are cloneable. It sucks when you've got a great shot and the flare is on the face though

07-19-2011, 11:38 AM   #122
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confused

My new Tammy 28-75 is taking some great shots just like I had hoped for, but it is inconsistent. A while ago I switched my focus area to a center spot then I recomposition because I was having similar probls with the kit lense and the kx doesnt have focus indicators.

Any suggestions? sometimes they are georgeous, sometimes rather blurry and I dont see any rhyme or reason to it. Tried some shots at a small aperature and was disappointed. Part of the reason then was that it was in full sun which I know can be difficult.

Also was does front loading mean in reference to a lense? How do I check it? Guess I should be a little more systematic, shooting the whole range of focal points and the whole range of f stops.

Thinking three shots each at 28mm, mid range, and 75mm. One at 2.8, next at mid f stop, and the third at the smallest f stop.

Thank you for any input.

Last edited by Genshu; 07-19-2011 at 11:46 AM.
07-19-2011, 06:25 PM   #123
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Although the 28-75mm has many virtues, I don't think it's known to be the most consistently accurate lens on autofocus, so I wouldn't expect every shot to be perfectly in focus. But that being said, it's probably at least average in that regard. I wouldn't describe my copy as bad in regards to accuracy and consistency, but autofocus will miss on some shots. This is true of all lenses, with some being worse than others.

But autofocus is a very complex subject, and is dependent on both the lens and the camera's AF system, and can be effected by things such as the amount of lighting, and even the type of lighting (sunlight, incandescent, fluorescent, mixed, etc). But since you said you were having similar problems with your kit lens, then there may be something else going on.

When shooting at f/2.8, depth of field (DOF) can be very thin. So autofocusing and recomposing will sometimes result in mis-focus. Also, if you or your subject moves even just a little bit, it can potentially throw off the focus. When photographing a person, for example, a slight turn on the head can throw the focus off, especially if you're shooting at close range, with a large aperture, and at longer focal lengths.

Finally, you may sometimes be confusing motion blur with misfocus. It's easy to do, and I know that I made that mistake a lot when I was newer to photography. There have been times when I was getting soft pictures and I initially thought there may be focus issues, but then when I upped the ISO and shutter speed, everything sharpened up, telling me the softness was not a focus problem.

Or, you may just have a faulty lens. But without actually using your lens, I can't really say whether it's a lens problem, or a matter of technique. And there could also be some unrealistic expectations thrown into the mix as well.

Assuming you have a return policy for the lens, you may want to exercise your option to replace or return it. If you're not happy with it, then there's no point in keeping it. And if you are still relatively new to photography, you may want to shoot some more with the kit lens (which is a decent lens) until you start to feel constrained by its limitations.
07-19-2011, 06:41 PM   #124
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QuoteOriginally posted by Genshu Quote
sometimes they are georgeous, sometimes rather blurry and I dont see any rhyme or reason to it.
That's generally a sign that you haven't controlled exactly where the camera will choose to focus well enough. Even specifying center point, it's not really a point - the camera might fo cus anywhere "near" the center. Sample images would help.

07-19-2011, 10:35 PM   #125
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When it all comes together I am LOVING it! Don't want to go back to the kit.

My sister in law took a class on photography and they had everyone in the class take all shots with manual focus. I love that idea, but it is not so easy these days without the focus helpers of yesterday (like split screen), also the focus ring on af lens these days has too narrow a range of movement. I do try to tune in to what the af is doing before taking the shot.

Hope I am not being overly optimistic, but I sure would like to not have to deal with taking the lense back and exchanging it. Hopefully the lense is fine and I need to improve my technique. I'll try going back to more focus spots and try to make sure what I want is in focus before taking the shot.
07-19-2011, 11:02 PM   #126
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The dog photo another impromptu shot is what inspired me to keep this lense! Al catraz shot is an off shot example, dont know why it is off. The photo of my kids and the Panda, my older son is slightly out of focus and the kid to his left with the hat, back to camera is spot on focus.

The lack of focus indicators is starting bug me after all about the kx, but I am trying to get more manual and engaged in the process anyway.

Unrealistic expectations and subject or camera movement prob does come into play sometimes. It seems sometimes that my wife's point and shoot panasonic has better anti-shake stabilization.

That being said I don't want to be too humble, I do know what I like and I do have a sharp eye!

Realized I should take some more shots with focus on infinity to make sure long distance is not a problem.

Thank you for all the input what a great web site!
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07-20-2011, 12:19 AM   #127
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Genshu you may already know, but let me remember what I know:

Focus system is based on contrast, red hat is very contrasy but your kid is in shadow.
better you may use some flash assistance or external flash with AF assist lamp.

Try single center point AF spot, trick the AF system with a different point,
eg focus very near or very far objects according to your main object, so that break the focus
then re point the main subject abd re adjust the focus. Use af lock with half shutter to re-make the scene, but Af should be on single mode not continuous.

use higher shutter speeds for shaking and f value for dof.

some lens have some front/back focus issue whic can be adjusted through debug menu, but it is somehow compilcated and drawbacks. better try battery or curtain test to decide it.
07-20-2011, 10:25 PM   #128
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Here are some more shots. Again some are coming out great, some not, feels good to be shooting more. Will try focusing on a different distance object then refocusing on subject.

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07-22-2011, 03:36 AM   #129
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Hi all, I just picked up a copy of the 28-75, largely inspired by Edgar and this thread, and the first thing I notice (aside from its weight) was the zoom ring is quite stiff.... not ceased or anything, but in comparison to the 18-55/50-200 kit lenses, there is a quite noticeable difference, is this a common trait of this lens?
07-22-2011, 09:46 AM   #130
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Don't know, mine feels fine. General feeling is that too stiff is better then too loose. Need to take some more shots but when manual focusing it really seemed that when focus is on infinity the shot is blurry, and that the actual infinity focus is a little backed off from turning the ring all the way. Anyone ever experience this?
07-22-2011, 10:16 AM   #131
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QuoteOriginally posted by Genshu Quote
Don't know, mine feels fine. General feeling is that too stiff is better then too loose. Need to take some more shots but when manual focusing it really seemed that when focus is on infinity the shot is blurry, and that the actual infinity focus is a little backed off from turning the ring all the way. Anyone ever experience this?
I have also noticed the infinity focus is a hair before the limit... based on a morning worth of random shots in my backyard....

The stiffness of the zoom ring is not a great concern of mine, and I understand the preference for too tight to to loose, I was just surprised the first couple times turning it.... I think I am just paranoid about the QC of this particular lens having spent months considering it reading all the comments about problems so I may be looking for problems.....
07-22-2011, 11:36 AM   #132
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Sounds like we're in the same boat Bob! These are big purchases for both of us! To be sure I just shot some more infinity with manual focus shots and the correct focus is definitely a little back from the end of the focus ring. Does anyone know if this is OK? I have done most of my photography pre AF and back then this never would be the case. Infinity focus was always on many different lenses the end of the focus ring.
07-22-2011, 11:43 AM   #133
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If you could would love to see some of the shots your taking Bob just for the curiosity of seeing how your lense is doing. Casual shots ok I wont judge them!
07-22-2011, 12:28 PM   #134
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Sorry, I haven't been keeping the shots as they have been mostly for testing purposes.... a couple dozen shots in the AM, then I checked them on the computer for a sense for the lens to make sure that I did not get a problematic copy.... then delete and move on...

Like I said, I am/was somewhat spooked by the numerous instances of problems talked about here so I was just doing some random focus testing shots here and there...

On thing I did notice is the infinity focus seems to correspond with the tick mark adjacent to the infinity symbol where as the lens its self will allow you to turn the focus ring slightly beyond the tick mark, more in line with the symbol.... some what of an annoyance, but I don't think it is an indication of faulty copy...

I am at work now, but I will try to post a few shots later/tomorrow if I get a chance.
07-22-2011, 12:34 PM   #135
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Out of curiosity, can anyone recommend a decent CPL for this beast that won't rival the cost of the lens itself as the treads are 67mm...

Thanks
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