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Old Sep 6, 2010, 6:04 PM   #31
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... I think I'll get the 17-70 for now and see how often I'm wanting a longer reach. ...
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Outdoors, even at the zoo and seaworld where I was using max zoom, my P&S shows a focal length max of 72mm. I seem to average around 17-20 for my wider shots outdoors, and 50-72 when I am zooming in.
That's the actual focal length that your Sony H5 used when capturing the image. The H5 has a 6-72mm zoom lens, but it also has a very small image sensor, so you can't directly compare the focal lengths you used with your H5 to the focal lengths you'll use with an A500.

In order to do what youwnat, you need to relate the actual focal length to the angle of view you got at that focal length. The conventional method for doing that is the 35mm equivalent focal length. That is, whatever the angle of view you got with your H5 is expressed in terms of the focal length lens that would give the same angle of view on a 35mm film camera. Simply put, your H5 has a 35mm equivalent focal length of 36-432mm, and you used a 35mm equivalent focal length of 102-120mm for your wider shots outdoors, and a 35mm equivalent focal length of 300-432mm when zooming in.

Since the A500 also has an image sensor that's smaller than a 35mm film exposure (though not nearly as small as the one in the H5), we need to do some conversion on this end too. On the A500, the angle of view on a 35mm film camera using a lens with a focal length of 102-120mm would be what you would get with a lens with a focal length of 68-80mm for your wider shots outdoors, and 200-288mm for when zooming in.

The 200-288mm sounds reasonable, but 68-80mm for indoors sounds long. How sure are you of those numbers? If you're not certain, before you spend maj0or bucks on a lens, I suggest you get the 18-55 kit lens to get a feel for how this works, and base your future lens purchases on your experiences with it.
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Old Sep 6, 2010, 6:09 PM   #32
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This might seem like a silly question, but are the focal lengths equivalent mm to mm with my H5 vs the lenses we are talking about?

I checked some of my recent pictures and the max focal length I'm seeing is 72mm, even on pictures where I know I had used max optical zoom.

Looking at the focal lengths I tend to be within 17-72mm almost all the time, unless I'm indoors where I don't tend to use zoom because lighting is not as good. In these cases it's more like 8-12mm. This is why I asked if there was some conversion I didn't know about.
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Old Sep 6, 2010, 6:17 PM   #33
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That's the actual focal length that your Sony H5 used when capturing the image. The H5 has a 6-72mm zoom lens, but it also has a very small image sensor, so you can't directly compare the focal lengths you used with your H5 to the focal lengths you'll use with an A500.

In order to do what youwnat, you need to relate the actual focal length to the angle of view you got at that focal length. The conventional method for doing that is the 35mm equivalent focal length. That is, whatever the angle of view you got with your H5 is expressed in terms of the focal length lens that would give the same angle of view on a 35mm film camera. Simply put, your H5 has a 35mm equivalent focal length of 36-432mm, and you used a 35mm equivalent focal length of 102-120mm for your wider shots outdoors, and a 35mm equivalent focal length of 300-432mm when zooming in.

Since the A500 also has an image sensor that's smaller than a 35mm film exposure (though not nearly as small as the one in the H5), we need to do some conversion on this end too. On the A500, the angle of view on a 35mm film camera using a lens with a focal length of 102-120mm would be what you would get with a lens with a focal length of 68-80mm for your wider shots outdoors, and 200-288mm for when zooming in.

The 200-288mm sounds reasonable, but 68-80mm for indoors sounds long. How sure are you of those numbers? If you're not certain, before you spend maj0or bucks on a lens, I suggest you get the 18-55 kit lens to get a feel for how this works, and base your future lens purchases on your experiences with it.
Now that makes much more sense. I thought I remembered reading a thread about focal length conversions because of the change in sensor sizes (I've read a lot of threads though)

Indoors I'm more around 6-12. That is why I wondered about conversion rates, the numbers didn't seem to add up. Phew. Lots of info to digest. And to think, my camera research was a break from my Differential Equations homework, lol.
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Old Sep 6, 2010, 6:47 PM   #34
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This might seem like a silly question, but are the focal lengths equivalent mm to mm with my H5 vs the lenses we are talking about?
No. You may have come across the terms 'Crop Factor' or 'Focal Length Multiplier'. These are attempts to reconcile the differences in angle of view when the same focal length is used with different size image sensors.

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I checked some of my recent pictures and the max focal length I'm seeing is 72mm, even on pictures where I know I had used max optical zoom.
That makes sense, since the longest focal length the lens on the H5 can zoom to is 72mm. That has a 35mm equivalent of 432mm which would be created on an A500 (and most other APS-C dSLRs) by a lens with a focal length of 288.

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Looking at the focal lengths I tend to be within 17-72mm almost all the time, ...
That would be 68-288mm on an A500.

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... unless I'm indoors where I don't tend to use zoom because lighting is not as good. In these cases it's more like 8-12mm. ...
That would be 32-48mm on an A500.

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Now that makes much more sense. I thought I remembered reading a thread about focal length conversions because of the change in sensor sizes (I've read a lot of threads though)

Indoors I'm more around 6-12. ...
That would be 24-48mm on an A500.

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That is why I wondered about conversion rates, the numbers didn't seem to add up. Phew. Lots of info to digest. And to think, my camera research was a break from my Differential Equations homework, lol.
This is just so you can figure out what focal length lenses you'll need on your A500 without actually trying it. Once you've bought the A500 and a lens, you'll have a basis for comparison.
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Old Sep 6, 2010, 7:20 PM   #35
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Diana-

Congratulations on your choice of the A-500, as your camera of choice. If the issue is to be as budget conscious as possible, why not begin with the Sony 18-55mm lens which is a good lens and the Sony 55-200mm lens which can usually be purchased on E-Bay for $100 and under.

Then when you get some experience with the A-500, your perspective on the lenses needed might be somewhat different. The Sigma 17-70 is a good lens. if you are getting the A-500 body only, the Sigma 17-70 makes even more sense.

Sarah Joyce
Budget is always in the back of my mind and is restricted, but I'd rather pay slightly more now than the bare minimum and quickly wish I'd spent a little more to begin with, if that makes sense? But I won't completely disregard the idea of the 18-55 and the 55-200.

I did plan on buying just the body. BH has a 70 difference between just the body and the body + the 18-55. I thought it would be a better investment to put that 70 towards the Sigma 17-70.

Though now that I understand the differences in focal lengths between my H5 and the lenses for the a500, I might change my mind, I dunno yet.

How would the sony kit lens compare to the 17-70 in terms of indoor lighting/low light situations?

For outdoors, I'm thinking that something like the Tamron 70-300 might work well.
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Old Sep 6, 2010, 7:29 PM   #36
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How would the sony kit lens compare to the 17-70 in terms of indoor lighting/low light situations?
The Sigma 17-70 is faster than the Sony 18-55 kit lens, but not so fast that, if you need a flash for the Sony, you wouldn't need a flash for the Sigma. The range is nicer, it's sharper, it focuses closer, but as far as "indoor lighting/low light situations", it's not much different.
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Old Sep 6, 2010, 8:06 PM   #37
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The Sigma 17-70 is faster than the Sony 18-55 kit lens, but not so fast that, if you need a flash for the Sony, you wouldn't need a flash for the Sigma. The range is nicer, it's sharper, it focuses closer, but as far as "indoor lighting/low light situations", it's not much different.
Good to know.

Okay, so hopefully my last question for a bit. How would either of these work for portraits? Or would I have to look at a different lens for that?

(thanks again!)

Diana
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Old Sep 6, 2010, 9:30 PM   #38
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Diana-

Here is the Sony 55-200mm used for portraits. The photo was taken with my 10mp A-230 DSLR.

Just click on the link below, please:

http://anchorse.smugmug.com/Other/So...6_bqx9N-X3.jpg

Now here is the same lens used as a telephoto. Again, please click on the link:

http://anchorse.smugmug.com/Other/So...3_r6T2M-X3.jpg

Finally, here is the A-230 with an old Sigma 18-125mm lens that I picked up at a garage sale for $19.00. This was taken without flash, using only stage lighting.

http://anchorse.smugmug.com/Other/So...7_FyafW-X3.jpg

One more, I just changed to the Sony 18-55mm kit lens to give a sample of that lens. It is night time and I needed to use the camera's built-in flash fairly close range on Bradley, my husband, so you can see he was not too keen on the idea.

http://anchorse.smugmug.com/Other/So...9_qG46D-X3.jpg

Naturally, you can expect better image quality from the A-500. But this will give you an idea what these lenses can do. Also an idea that these lenses do not necessarily have to cost and arm and a leg.

Sarah Joyce

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Old Sep 6, 2010, 10:08 PM   #39
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Those all look good to me.

For 19.00, looks like you got a good deal
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Old Sep 6, 2010, 10:12 PM   #40
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Diana-

It was only the Sigma 18-125mm that I picked up for $19.00. The Sony 55-200mm I purchased on E-Bay for $72.00, and the Sony 18-55mm came with my A-230. But now you have actual photos from these various lenses.

Sarah Joyce
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