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07-04-2011, 10:12 AM   #76
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Edgar, from the last batch your lighting is super diffused and very even. Is it indoors or in the shade? Do you use a reflector to lift up shadows at all? I figured using reflector would be hard with children portraits though.

07-04-2011, 11:11 AM   #77
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No, no flash or reflectors. And I don't believe that any of the pictures were taken in the shade. It was a partly cloudy day in mid-to-late afternoon. As far as the even-ness of the lighting, I always shoot RAW and will often lift shadows using the Adobe Camera Raw "fill light" slider and by tweaking the curves.

But if I don't think the lighting is favorable, then I probably won't take the picture in the first place. So most of my "keepers" don't end up needing too much correction. If it had been completely sunny that day and the sun were right over head, I probably wouldn't even have gotten my camera out.
07-04-2011, 06:44 PM   #78
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QuoteOriginally posted by Edgar_in_Indy Quote
My understanding is that if you're shooting RAW, it doesn't make a difference whether you have the camera set to sRGB or Adobe RGB. I think that setting only effects JPEGs. I always shoot RAW, and would view the RAW files in Adobe Bridge and then open them in Photoshop CS4 (and now CS5) using Adobe Camera RAW. Once I was done with the image, I would save it as a JPEG and call it done. When I was posting some sample images from my Tamron 28-75mm in this thread: DA 15-60* or Sigma 17-50? I noticed that the images were washed out and the colors were off. With the help of forum members, I discovered that I needed to covert to sRGB before saving to JPEG for proper viewing on the web. I do this in Photoshop CS4/CS5 by clicking "Edit"-->"Convert to Profile". People say that Adobe RGB has a wider color gamut and is technically superior to sRGB, so it may be better for printing. I don't know how true that is, but now my normal workflow is still to save my full-size images without converting to sRGB. But when I'm preparing something to view on the web, I convert it to sRGB. If you want to see the difference between sRGB and Adobe RGB in your browser, you can pull up the above thread in one window and look at the pictures I posted, and then pull up the first page of this thread with the same pictures converted to sRGB, and flip back and forth. __________________
WOW, thank you so much, that really helped me a lot and the pictures in this thread do look better. Awesome job btw.
07-04-2011, 10:30 PM   #79
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QuoteOriginally posted by haassaasin Quote
I am just asking because OP said that his pictures were not clear on the web until he converted them. So I assumed you had to convert them before posting.
That's only because he wasn't using sRGB in the first place - he was using Adobe RGB in Photoshop. If you haven't explicitly taken steps to use something other than sRGB - whether by setting your camera to use Adobe RGB, or by your settings in your PP program - then you are using sRGB.

07-05-2011, 07:10 AM   #80
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QuoteOriginally posted by Marc Sabatella Quote
That's only because he wasn't using sRGB in the first place - he was using Adobe RGB in Photoshop. If you haven't explicitly taken steps to use something other than sRGB - whether by setting your camera to use Adobe RGB, or by your settings in your PP program - then you are using sRGB.
Actually, I don't think I ever specifically selected Adobe RGB. I think that was the default setting. For anybody else using Adobe Camera Raw to develop your RAW pictures, I just figured out that you can change the default color space by clicking below the image when "Camera Raw" is open. Here's a screenshot I just grabbed from Adobe Camera Raw 6.0:

07-05-2011, 10:25 PM   #81
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well , I just got it! Pretty exciting, will get some photos up on here soon!
07-05-2011, 11:24 PM   #82
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QuoteOriginally posted by Jewelltrail Quote
Edgar, since you are not clear about why I make certain points, I’ll try again. However, this time I’ll try a different route, so please do not take me as being curt--okay?

In a nutshell, you can not compare a wide-to-normal lens to a near-normal-to-short-telephoto lens and call that apples to apples--IT IS THAT SIMPLE!

Compromises go into wide angle design--compromises which affect performance in other areas, particularly vignetting. Let me give you a concrete example of why your illustration is not apples to apples. What are the vignetting numbers for the 28-75mm @ 17, 18, 19, 20 and so on MMs? There are none, because the 28-75mm is not apples to apples to 17-50mm--right? However, ironically for our discussion, there is a way to provide apples to apples for these 2 lenses because they each provide almost exactly the same focal range on their designed format--right? In other words, on their designed formats, each lens is a wide to normal lens--in other words, on their respective formats, the lenses are apples to apples. ta----daaaaaaaa.

Natural vignetting is unduly affected by wide angle lenses. Again, Natural vignetting is unduly affected by wide angle lenses. Conversely, Natural vignetting is not unduly affected by normal lenses. Is this helping?

If you want apples to apples, place each lens on their intended mounts and look at the vignetting numbers. The reason I did not provide vignetting numbers for the 28-75 on APS-c is because those numbers have no place in this discussion. Now, once again, the reason I got into this discussion is because you wrote something which is not accurate. Here it is again:



Am I more clear in this post? The vignette performance of the 17-50 is not a weakness; rather, it is an inherent result of designing a lens from wide to normal--. Also, and again, this is NOT, as you say, “typical for lenses designed for APS-C as opposed to lenses designed for full frame (such as the 28-75mm).” In fact, vignetting is much more typical of lenses designed for full frame. PERIOD!!!!!

Okay, sure, you have a purpose in this thread. You wish to explain the awesome nature of the 28-75. I too bought a 28-75mm Tamron, because I knew it was great value. I too wish to relay its awesome nature here in this thread--but I will not make unfounded claims for its performance---this is our point of departure. You started the thread, this does not license you to censor or dogmatize its content. Okay, I am finished--will not return to this thread now because I have done all time will allow me to do. Best of luck to you.
No, just the Tamron 28-75 is best than 17-50 on APS-C camera, compared in the same focal range (28mm to 50mm). In APS-C żok?

Pentax have only APS-C sensor, and If in future have an FF, then the 17-50 do it worse than 28-75
If I need a lens for that range of focal, (28-50) Tamron 28-75 is best than Tamron 17-50, Just that.
If I need more wide or more tele, that is other point to analyze in the moment of decision.



Very sorry for my terrific English
07-06-2011, 07:33 AM   #83
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QuoteOriginally posted by Edgar_in_Indy Quote
Actually, I don't think I ever specifically selected Adobe RGB. I think that was the default setting.
Good to know if so! I guess that sort of makes sense that Adone would push their own format this way. Most programs would default to sRGB, though.

07-06-2011, 11:34 AM   #84
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Thanks for sharing your technique, appreciated Unfortunately sometimes I do have to shoot under the full sun
07-06-2011, 01:07 PM   #85
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When I was shooting Pentax, this lens was practically glued to my K10D. Out of all the lenses I had, it was the last one I sold too, just in case the body didn't sell. Congrats on discovering an economical beauty. I don't know if the photos in my sold thread can still be accessed, but here are a few more examples of what this lens can do (keeping in mind macro-esque fun). Cheers, A.
07-06-2011, 10:36 PM   #86
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So here are my first shots with the 28-75. Just quick shots around the house. They are raw, but untouched. I only have iphoto and havent gotten into the whole computer end of the game yet. First thing is to determine whether this particular lense is ok. I will need to shoot more, but so far so good. I believe any blurriness is due to the 2.8 speed. I wouldn't want anything faster because the DOF would be just too short. Feels pretty good!!!
07-06-2011, 10:39 PM   #87
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one more of flowers. Do you think my lense is up ok?
07-07-2011, 04:19 AM   #88
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The pictures look good for impromptu shots. Did you say you shoot RAW? If you have a way of posting the RAW files for download so that myself or some other forum members can take a crack at them, I have a feeling the shots of the kids could be much improved in developing. The first picture in particular could be a very nice portrait. If you want to email me the RAW file for the first picture, I could see what I could do. Feel free to PM me for my email address.

As far as evaluating whether you got a good lens, it would be hard to do from such a down-rezzed picture. The flower picture does look good though. If it's decently-sharp at 100% magnification, then I'd say your lens is good.
07-07-2011, 10:37 AM   #89
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QuoteOriginally posted by Genshu Quote
I believe any blurriness is due to the 2.8 speed. I wouldn't want anything faster because the DOF would be just too short.
Yep, that's generally the case. Although in the last shot, I think there is both a DOF *and* a motion blur issue. Still, f/2.8 usually seems to be the sweet spot in most indoor settings for compromising between these two conflicting concerns.
07-07-2011, 10:33 PM   #90
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Thank you for the input. Sent you a pm Edgar. Been a crazy busy week, hope to have some more time during the weekend to take side by side comparison shots with the Tamron and the kit lense. By 100% magnification do you mean like cropping a small piece of the photo and seeing what it looks like?
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