Second, your camera must be in Manual Mode so you can set shutter speed and f-stop.

Third, you’ll need a cable release for exposures longer than 30 seconds. For long exposures your shutter setting will be on "B" which allows you to keep the shutter open as long as you want.

Suppose you want to photograph a city skyline in the distance after dark. Using my trusty FotoSharp (fotosharp.com) Day & Night Exposure Guide, Scene # 14, we find:

ISO 100

f5.6 @ 15 seconds
f8 @ 30 seconds
f11 @ 60 seconds

ISO 200

f5.6 @ 8 seconds
f8 @ 15 seconds
f11 @ 30 seconds

ISO 400

f5.6 @ 4 seconds
f8 @ 8 seconds
f11 @ 15 seconds

Your best quality will be at ISO 100 @ f8 or f11 since lenses are optimized at between f5.6 and f11.

Experiment with the settings listed BUT change only ONE variable at a time. That avoids confusion.
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Now for the longer answer as you already have some experience I will be preaching to the choir on a good bit of this.

I would say the Nikon D40 Its an entry level DSLR. A digital SLR will give you a much larger sensor than any point and shoot camera. Larger sensor = more light to each pixel = clearer, crisper photo with better color saturation. DSLR will also let you grow and take more control as you learn more and you can change lenses when you have a need to. The sensor on the olympus is smaller than on Nikon or Canon

I am a nikon person and have had nikons since the 70’s I personally think the nikon D40 give you more for the dollar than any DSLR today. There are some that do more but you pay a good bit more. Do not let the lower megapixels concern you if you do not do very very large prints you will never notice the lower DSLR. My brother recently needs a DSLR for a class and I recommended the D40 to him So I would also say get the D40 not the D40X. The Nikon D40 does not have limited functions compared with other entry DSLR. Yes it has fewer funtioncas than a 1500 dollar camera body would. It is not a a cut down version its equal or above most any entry level DSLR.

There is a great article in this months Digital Photopro Magazine that is titled "Megapixels how much is enough" EVERYONE looking at buying a new digital camera can profit by reading this article. Its here
http://www.digitalphotopro.com/studio/megapixels-how-much-is-enough.html

I have a d300 and a d40 and when I am shooting for fun I grab the d40. Its weightless, a joy to use and gives good results

If you have a bit more money the D60 give you a number of things you want. It has newer firmware and image processors, designed for the 10 mp sensor. It has an "Active Dust Reduction System with Airflow Control ". Nikon not putting a system on the D40 to deal with dust is one of the biggest drawbacks I see to the D40 ( though I think its still a great camera for the money) If you change lenses dust will get in and the camera needs a system to deal with it. With the D60 you get a VR lens. That will help with low light situations ( they may offer that now with the D40 but originally it was not) . The D60 has Adaptive Dynamic Range. Nikon calls it "Active D-Lighting," it lets you save some highlights that my otherwise be lost. It has a newer better metering system than the D40. So you can get the D40 not the D40 x and spend the other money on lenses or a flash

Some people will want to make a big issue out of the fact that there are some nikon lenses that will not autofocus on these cameras. Right now there are "only" about 39 lenses that autofocus on these cameras. They cover the range of focal lengths. I doubt any photographer would be seriously limited with "only" this many lenses to choose from. If you want to manually focus you can more than double this and do so at a low cost. Manual focusing is easy and how we did things for decades before the advent of autofocus.

Cannon and Nikon chose to put the vibration reduction in the lens rather than the body. Somefolks put it in the camera and make of that. Yes that means you get stabilization only on lenses with that feature built in. In the body in theory it would work on every lens. But in fact image stbilization in the lens has proved to work faster and smoother with a lower impact on focus times than image stabilization in the body/ One problem with in body stabilization comes from the fact that the sensor would have to move different amounts for different focal lengths. A canon white paper says an in body system would have to move the sensor 1/4 inch to account for movement on a 300 mm lens.

Now a comment on liveview. Have you ever tried to hold several pounds of digital camera and lens steady at arms length while you look at an LCD screen. It not at all the same as holding a few ounces of point and shoot camera steady in the same position. One of the things we preach to new photogrpahers is to learn to hold the camera properly so the body mechanics give you a steady shot. You can’t really do that looking at the LCD. So liveview is really something that will have very limited applications in a DSLR. Usually only when its on a tripod. I have liveview on my D300 and have never used it.

Nikon also has great service. I was just reading the other day on eyefetch in the Nikon forum where someone posted that they had dropped thier lens and broken it. It was not a fault of the company they messed up. The sent it to Nikon and Nikon could not fix it. Nikon offered them a brand new identical lens at half the price. They did not have to

In closing all major camera manufactures make good cameras get out and compare the features and how they feel in your hand. Go to places like kenRockwell.com and DPreview.com to compare them. Nikon and Canon have the largest market share and I personally think there is a very good reason they do. Not bashing other brands but photographers tend to be very very demanding folks and they then tend to be loyal to what has worked for them well and consistently. That is not a pavlovian response anymore than it is a pavlovian response in my work at the fire department when I trust the brands of turnout gear and airpacks that have worked for me time and time again. Sometimes even going beyond the published specs. People in ANY demanding profession gain loyalty and trust from thier experiences. And if the product did not perform it would not be favored for long.
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When they say you can drive a nail with a Nikon, they aren’t kidding.

I have never had my Nikon fail, even after dropping it off a tripod onto asphalt. The things are really durable.

I have however, received a fair amount of Canon bodies into the camera shop in need of repairs after they have been dropped… I can say they come in about 4:1 over other cameras but then they may be out there at that same ratio. I can say Canon has an excellent customer support system.

Originally, you saw nothing but Nikons at sporting events then Canon took center stage but recently, it appears that the Canon shooters are coming back to the Nikons for some reason.
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Or 50 bucks for a tripod.

Up 2 U.
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http://i30.photobucket.com/albums/c317/wtin/0c9c2751.jpg

Griffith Park Observatory, November 2006, freezing cold at night.

Canon 5D, Canon 16-35 mm f 2.8 L and Canon 100 mm f 2.8 Macro.

The camera set the speed shutter at 10 seconds. It was waaaay overexposed. So I vetoed it, and put it in manual mode, and set it at 1.5 second instead, and I thought it looked better.

Absolutely you need a tripod. I forgot my cable release–so I put it on a self timer. Other people standing near me were taking photos with flash (which didn’t work really).

Hope this gives you some idea.

ISO was at 500.
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If she _REALLY_ wants to have slides made from digital picture files, find a photo lab in your area that deals with professional photographers. I’ve had to go this route once. What they’ll most likely do (what they did with my work) is make a large paper print from the digital file, then use take a picture of that using slide film.

I’ve tried making slides using overhead transparency sheets in my printer. Even using the highest quality print dpi, the results were useless…

—

If she needs to make a "slide show" presentation to a group meeting, she could always store the images digitally on a CD in a PowerPoint presentation – most meeting places have digital projectors these days….
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