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12-17-2010, 04:26 PM   #91
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QuoteOriginally posted by Jewelltrail Quote
I use 3 different free programs. So I really can't get the max out of my Raw files
Do you use GIMP? It really gives photoshop a run for it's money IMHO... not much reason to buy photoshop.

12-18-2010, 12:52 AM   #92
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QuoteQuote:
paperbag846: I really think the value of the 16-50 lies in weather sealing, SDM, quickshift, etc.

If you don't need these things, you are paying an awful lot for features you might not use.
Agreed!
QuoteQuote:
paperbag846: Do you use GIMP? It really gives photoshop a run for it's money IMHO... not much reason to buy photoshop.
No, I use Faststone, Picasa & Helicon Filter--mostly Helicon Fliter. However, now that you have made this recomendation, I am going to try it. I never dreamed there was a software out there (free) to rival Photo shop--amazing! Thank you, very much.
12-18-2010, 01:24 AM   #93
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QuoteOriginally posted by Jewelltrail Quote
I never dreamed there was a software out there (free) to rival Photo shop--amazing!
I hope you find a good use for it. I'm a computer nerd first, and I'm a hugefan of a number of open source projects. GIMP is more than enough for most people who use photoshop in a non-professional setting. It's really quite powerful... the major drawbacks of it are it's ugly interface and steep learning curve.

But the learning curve applies to photoshop as well.

Another to keep your eye on is "Scarab Darkroom". It's a beta right now, and frankly none too useful. However, with some file-handling tweaks, it could be a very useful free lightroom replacement, although one would have to do most of the heavy lifting in GIMP.

I'm going to have to try this helicon filter program... looks mighty useful.
12-19-2010, 04:51 AM   #94
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Just when I thought I was done and had decided on the Tamron 17-50 (and also picking up a Tamron 28-75 2.8 off the local version of Ebay for US$80 tomorrow - if it's still there) then I read this test on the new Sigma 17-50 on Lenstip that someone posted in another thread, here's the summary (hope it's OK to post it here - if not then a mod can please delete it for me) - damn it really sounds good ! Beating out both the Canon 17-55/2.8 and, in some areas including sharpness, the Nikkor 17-55/2.8.

I guess I really will have to control my LBA and wait until my stockist has them both in store

Pros:
• high build quality and very solid barrel,
• sensational sharpness of images in the frame centre even at the maximum relative aperture,
• decent image quality at the edge of the frame,
• chromatic aberration well-controlled at longer focal lengths,
• negligible astigmatism,
• silent, quick and accurate autofocus,
• efficient image stabilization,
• three-year-long guarantee period with the possibility of extending it by additional two years.
Cons:
• noticeable chromatic aberration at the shortest focal length,
• a bit too high vignetting,
• significant coma at 17 mm,
• too simplified manual focus ring,
• image quality at the maximum aperture, at the edge of the frame for shorter focal lengths could have been better.

Reading our test you can see very clearly that the Sigma entered the segment of more expensive fast zoom lenses, aimed at ambitious amateur photographers or even professionals working with smaller sensors, very aggressively indeed. The performance of the tested lens is sometimes really impressive. In the frame centre the Sigma behaves better than more expensive constructions of Canon and Nikon. At the edge it is worse than the Nikkor but it can compete on equal terms with the Canon. In fact it doesn’t lag behind the competitors in any category and in some it fares definitely better. Sigma lately has started to emphasize the fact that its aim is not only to produce cheap and worse substitutes of brand name lenses but also to reach a similar price-quality segment as its brand name competitors. The newest models, like the 1.4/50 or the Sigma 17-50 mm f/2.8 tested here, are perfect examples of this strategy.
The Sigma 17–50*mm is not a flawless device but neither are so its most serious competitors which are more expensive. The Nikkor overall seems to be an optically better lens but it is much more pricey than the Sigma and doesn’t feature image stabilization. The optics of the Sigma and the Canon are very similar – both boast silent and quick autofocus mechanism and stabilization. Sigma’s advantage consists of a better warranty and a bit lower price.
For the Sony Alfa system reflex cameras users the Sigma 17-50 mm can be a very interesting suggestion because Sony doesn’t offer such a lens in its line-up so the competition is definitely less fierce. It won’t be so easy in the case of Pentax because the 16-50 mm f/2.8 model from that company tempts with a wider angle of view although it is optically worse and more expensive than the Sigma.
To sum up the Sigma 17–50*mm f/2.8 EX DC OS HSM will find many satisfied users for sure. It would be difficult not to be satisfied when you can take photos as good as or even better than the brand name competitors using a cheaper lens.

12-19-2010, 06:39 AM   #95
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Service

One major aspect to also consider is service. My local shop (in Canada) says that his Sigma distributor does and admirable job of providing super fast service and delivery. This is specially important in an era of SDM motors failures that seem to be a trend. Warranty repairs is important too since claims denials is a thing often ovelooked.
12-19-2010, 08:54 AM   #96
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QuoteOriginally posted by paperbag846 Quote
I really think the value of the 16-50 lies in weather sealing, SDM, quickshift, etc.

If you don't need these things, you are paying an awful lot for features you might not use.
Plus the extra mm at the wide end. If I were working at weddings, presentations and similar events, the SDM or something similar would be a big deal to me. I've had all eyes on me too often because of AF chirp.

At the time the DA*16-50 was introduced, there was no real competition in IQ, speed, etc. near that focal length range in PKA. It was only a matter of time, now four years, until other manufacturers offered something comparable.

I don't own any of these lenses (opted instead for the DA17-70 as my quiet zoom), but at this point in time, I'd have to try the DA* and be convinced that it really improved my work before I spent twice the money to carry 30% more weight and 25% more length in my bag to do this job.
12-19-2010, 12:08 PM   #97
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QuoteQuote:
GeneV: At the time the DA*16-50 was introduced, there was no real competition in IQ, speed, etc. near that focal length range in PKA. It was only a matter of time, now four years, until other manufacturers offered something comparable.
Good point, introduction date plays a key role in each lenses' performance here.

Da* 16-50 2.8 4 years ago
Tamron 17-50 2.8 2 & 3/4 years ago Febrruary 2008
Sigma 17-50 2.8 (new release) December 2010


QuoteQuote:
Frogfish: I guess I really will have to control my LBA and wait until my stockist has them both in store.
Fantastic for you--also for me--I can't wait to see some shots with this beauty. If I like them enough, I may sell the old Tammy and get this beauty.
12-21-2010, 10:20 AM   #98
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Sorry JT - I couldn't control the LBA

Today I went into my favourite stockist and the new Sigma 17-50 still wasn't in stock yet (and no date on delivery) .... so I bought the Tamron 17-50/2.8 instead.

I'm really looking forward to using this lense but the next time I'm there (and the Sigma is in stock) then I'll give it a run out, if I like it more then I won't lose too much by switching.

I tried out 4 copies of the Tamron today (checking for FF/BF) and as thankfully I have a split prism screen it was very easy to check the focus in the viewfinder even before I took a shot. Not one was on the money so I chose the best of the 4 and then used the K7's focus adjust to fine tune it (+5) to perfect.

I don't know how accurate this is but the owner of the shop told me that as the Tamron is made for multiple mounts it isn't adjusted in factory specifically for each brand (the mounts are simply added to the lenses after production) hence the problem with FF/BF. I wonder if this is true and if so is it the same for all 3rd Party lenses ?

Therefore my advice to anyone else buying this lense is to not buy it on-line. Buy in person, check multiple copies, and beware if your camera can not adjust focus for individual lenses.

Now I'm really looking forward to using this lense over Xmas / New Year ! Thank you again for all your help in guiding me to this decision.


Last edited by Frogfish; 12-22-2010 at 06:27 AM.
12-22-2010, 12:25 AM   #99
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QuoteQuote:
Frogfish Sorry JT - I couldn't control the LBA

Today I went into my favourite stockist and the new Sigma 17-50 still wasn't in stock yet (and no date on delivery) .... so I bought the Tamron 17-50/2.8 instead.

I'm really looking forward to using this lense but the next time I'm there (and the Sigma is in stock) then I'll give it a run out, if I like it more then I won't lose too much by switching.

I tried out 4 copies of the Tamron today (checking for FF/BF) and as thankfully I have a split prism viewfinder it was very easy to check the focus even before I took a shot. Not one was on the money so I chose the best of the 4 and then used the K7's focus adjust to fine tune it (+5) to perfect.

I don't know how accurate this is but the owner of the shop told me that as the Tamron is made for multiple mounts it isn't adjusted in factory specifically for each brand (the mounts are simply added to the lenses after production) hence the problem with FF/BF. I wonder if this is true and if so is it the same for all 3rd Party lenses ?

Therefore my advice to anyone else buying this lense is to not buy it on-line. Buy in person, check multiple copies, and beware if your camera can not adjust focus for individual lenses.

Now I'm really looking forward to using this lense over Xmas / New Year ! Thank you again for all your help in guiding me to this decision.
Mr Froggy, you have let me down. It seems, afterall, you are made of the same stuff as the rest of us LBAers. I was looking to you, as inspiration.... as a possible leader, to guide me out of this Labyrinth.

Seriously though, what you say makes a lot of sense. It was kind of you to post it for us--it probably would serve more good over in the Tammy Club though. You solved the problem of getting a good copy with old-fashioned, common sense. Some here make it sound like searching for the Holy Grail, when they describe the path to a good copy. You haven't let any of us down afterall--tx. JT

btw, if you are right, & I think you are, it also explains why people send one in for repair and it comes back not fixed, or perhaps even worse in some cases. Companies nowadays have removed the Quality Control department, instead placing that resposibility in the hands of the consumer. At least Tamron gives a buyer 6 years to keep trying until they get the right mount for their body--hey, sounds a bit like marriage. ooops
12-22-2010, 06:39 AM   #100
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So sorry to let you down JT, I guess I am not made of leadership material and am in fact just another white mouse in the maze with the rest of you LBAers

I am thinking of starting a LBA Anonymous branch and applying for Govt backing ... however I fear there will be two problems to overcome :

1. Too many addicts, and will actually end up encouraging each other to buy lenses we are considering buying ourselves !
2. I will spend the Govt support on new lenses

*sigh*
12-22-2010, 06:31 PM   #101
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I just purchased the tamron 17-50 at b&h, as there are no stores close to home. But, I decided to pay the premium over what they fetch on eBay just so I can return, if I get a bad copy. Out of the four you tried, how bad were the ones you didn,t get?....were any of them uncorrectable with af adjust and did some need different correction for different focal lengths.

P.s: typing from a phone, so pardon the errors
12-22-2010, 06:56 PM   #102
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QuoteOriginally posted by pcarfan Quote
I just purchased the tamron 17-50 at b&h, as there are no stores close to home. But, I decided to pay the premium over what they fetch on eBay just so I can return, if I get a bad copy. Out of the four you tried, how bad were the ones you didn,t get?....were any of them uncorrectable with af adjust and did some need different correction for different focal lengths.

P.s: typing from a phone, so pardon the errors
There was a distinct difference in focus between #1 and #4, using the split prism it was easy to see straight lines didn't line up and then after taking the shot not one was in focus. Adjustment was trial and error and took maybe 5 mins. but I only did this on the lense I chose out of the four.

I found the AF to be very fast and yesterday when I used the lense for the first time I was surprised how it still easily found focus even in very low light.

https://www.pentaxforums.com/forums/post-your-photos/126657-landscape-sunset-...west-lake.html
12-22-2010, 07:10 PM   #103
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Holy smokes, those are some impressive images.....looks like I made the right choice. I hope I get a good copy and if I do, I'll sell my 16-45/4.
12-23-2010, 01:19 AM   #104
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QuoteQuote:
Frogfish: I found the AF to be very fast and yesterday when I used the lense for the first time I was surprised how it still easily found focus even in very low light.
Yes, those are my findings with it too. More surprising, it does not hunt for focus--not in very low light--though it surely finds focus more slowly in dimness. I guess I could make it hunt if I tried, but in applications I use, some of which are low light, hunting is non-existent. This is, IMHO, one of the best kept secrets of the lens: it has always stumped me that others do not comment on it.
12-23-2010, 02:34 AM   #105
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i tried the new sigma 17-50 today....very nice...very quiet ..very sharp......very much want it..:}

the Focus ring locked up if you enabled the AF switch on the lens body..is that normal?

all my other lens can be focused manually even in AF..
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