Thread: ***DSLR Thread***

Very nice pic.

Originally Posted by SmytheKing

...For some reason though, the colors are off on the upload. It's less purpley and more blue sky and the clouds actually have more orange in there. Not sure why that happens but I seem to see it on occasion.

This is most likely due to color management. What color space are you saving out at? Anything other than sRGB and chances are it will render incorrectly in your browser.

The issue is this, for 8 bit spaces, each channel can contain a value of 0 through 255. So if for a given pixel the red channel is 255, and the green and blue channels are 0, that pixel is red. No problem so far. The question is, how red is that red? 255,0,0 in sRGB is a different red that 255,0,0 in Adobe RGB. The sRGB gamut is pretty small, it was designed do that the vast majority of monitors and printers could reliably reproduce the whole range of colors in the sRGB gamut. So sRGB's pure red, 255,0,0, is not as red as say Adobe RGB's red. There are more colors in the Adobe RGB color space, so the most red you can have in sRGB space (255,0,0) is mapped to 245,0,0 in Adobe RGB space, leaving room for more red reds.

In color managed images, they carry a little tag which tells a color managed application which color space it use to render the image. If you were working in something like Lightroom or Photoshop, their default behavior is to work in a color space which is not sRGB. If you export out of a color managed application without setting the output to sRGB, you will see it render incorrectly in a non color managed application (Internet Explorer, Firefox, etc.), while looking OK in a color managed app.

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Couldn't find the resource that I wanted about color management, but this one isn't bad:

got a sweet new lens for my olympus, 45mm f/1.8


P9232767 by Qmüngous, on Flickr


P9232759 by Qmüngous, on Flickr


PA032828 by Qmüngous, on Flickr

Originally Posted by VF

Very nice pic.



This is most likely due to color management. What color space are you saving out at? Anything other than sRGB and chances are it will render incorrectly in your browser.

The issue is this, for 8 bit spaces, each channel can contain a value of 0 through 255. So if for a given pixel the red channel is 255, and the green and blue channels are 0, that pixel is red. No problem so far. The question is, how red is that red? 255,0,0 in sRGB is a different red that 255,0,0 in Adobe RGB. The sRGB gamut is pretty small, it was designed do that the vast majority of monitors and printers could reliably reproduce the whole range of colors in the sRGB gamut. So sRGB's pure red, 255,0,0, is not as red as say Adobe RGB's red. There are more colors in the Adobe RGB color space, so the most red you can have in sRGB space (255,0,0) is mapped to 245,0,0 in Adobe RGB space, leaving room for more red reds.

In color managed images, they carry a little tag which tells a color managed application which color space it use to render the image. If you were working in something like Lightroom or Photoshop, their default behavior is to work in a color space which is not sRGB. If you export out of a color managed application without setting the output to sRGB, you will see it render incorrectly in a non color managed application (Internet Explorer, Firefox, etc.), while looking OK in a color managed app.

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Couldn't find the resource that I wanted about color management, but this one isn't bad:

That's an excellent explanation that you gave there. I'm like 100% sure that's what is happening. You learn something new every day. I'll have to check on that. I guess that if I'm working in LR and want to post it somewhere that I just have to accept that or is there a way to get it working appropriately?

PA042889 by Qmüngous, on Flickr

030 by Unholygoalie, on Flickr

L1002170 by Qmüngous, on Flickr


L1002194 by Qmüngous, on Flickr

L1002310 by Qmüngous, on Flickr

I have a question, I don't know much about DSLRs, but my wife has a simple Canon Rebel T3 and she would like a lens that zooms further than the lens the camera comes with.

Is the Cannon 75-300 a good buy? How much more would it zoom?

Amazon.com: Canon EF 75-300mm f/4-5.6 III USM Telephoto Zoom Lens for Canon SLR Cameras: CANON: Camera & Photo

The usual kit lens (the one that would have come with the camera) would be the EF-S 18-55mm. If this is the case, the 75-300 is a great deal longer. Here is a site that has a little tool that lets you slide though zoom ranges to get an idea of what the look like: Focal length comparison tool, Tamron USA

As for if it is a good buy, is she is happy with the quality of the kit lens, the build of the 75-300 is about the same.