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10-22-2011, 01:59 AM   #1
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x90 Av mode problem

I am trying to capture a basic narrow aperture shot of my little boy with an out of focus background and have turned the dial to Av and set the aperture to between 2 and 4 depending on the shot. all the results seem to capture him and the background in full focus--ie ap seems to be wide open. am i missing something?



10-22-2011, 08:40 AM   #2
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I am only a novice in DSLR field. So I may not give you the best advice. At first, I would like to clarify that you need wide open aperture to decrease the DOF (to blur the background). The larger F number the more narrow aperture (small F numbers refers to wider aperture).
As I understand, you tried to shoot at aperture between F2 and F4. Such F numbers refers to wide aperture. Theoretically, you should have reached a narrow DOF because such F numbers are typically used for such a purpose.
I presume that reason might be the too close distance between the object and the background. If it is true, then both the object and the background fall in DOF despite the shallow DOF. In order to check this my presumption, I recommend you the following things:
1) Check your lens maximal aperture (minimum F number). It could be found in the lens or in lens documentation. I also could be found on this site (see lens’ section).
2) Choose some close object that is located from background quite far.
2) Choose the Av (Aperture) mode and try to sett the F number to the minimum. Then focus camera to this close object Then shoot. Check the photo. If all works well, you should get a sharp image of the object with blurry image of background. If the background also is quite sharp, try the next step.
3) Choose the portrait mode and then focus on the chosen object. Actually this step replicates the previous. Only this step is performed by automatic mode. If this step allows you to get the desired result, then the problem is with Aperture mode. If this step also do not results in the sharp image of the object with blurry background, then there problem might be related to several reasons.

Check the information about aperture for your pictures. Does the indicated aperture is F2..F4? If is differs from the aperture you set during shooting (the camera show something higher than F2..F4), it means that camera arbitrary sets different aperture. If the indicated aperture is the same you set, then it could mean that camera incorrectly detects the aperture of the lens.

Could you specify the lens you are using?
10-22-2011, 08:46 AM   #3
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Sounds like you're actually experiencing the expected behavior, as higher aperture means more dof. Plus, due to its design, your x90 doesn't have the ability to make ultra shallow dof.
10-22-2011, 11:45 PM   #4
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QuoteOriginally posted by sazzie Quote
I am trying to capture a basic narrow aperture shot of my little boy with an out of focus background and have turned the dial to Av and set the aperture to between 2 and 4 depending on the shot. all the results seem to capture him and the background in full focus--ie ap seems to be wide open. am i missing something?
Getting a sharply focused target image with an out of focus background is a difficult task with the X90 because of its small sensor design, but it can be achieved with a bit of fiddling.

Step 1: Set up the target (your little boy) where you want him, and estimate roughly the distance between the camera and your son. Make sure the distance from your son to the background is at least four times (or more) the camera to target distance. So if you are holding the camera and you are 2,5 metres away from your son, the background must be 10 metres or more behind your son.

Step 2: Set your exposure to centre-spot measured brightness.

Step 3: Set your zoom to 5x which equates to 130mm (35mm equiv) which is good for portraits. When you move the zoom lever under the shutter release button, the zoom level indicates on a bar at the bottom of the screen, but also shows the actual value on the right. Make sure you get above 3.7x but do not exceed 5x. If you cannot frame the shot, move closer to, or farther away from, your son but keep the target to background distance at least four to five times more than the camera to target distance.

You cannot possibly get a blurred background when you are zoomed out to wide-angle. Anything more than about a metre away is at infinity and will be in focus, obviously including any background.

Step 4: Select Av mode and dial the e-dial all the way to the left. At a zoom of 5x the largest aperture you can set is F4.0 and it should have a small arrow to the right of it. Keep the ISO as low as possible and don't even try this in bad lighting conditions. You need good light.

Step 5: Set manual focus and focus carefully using the four-way switch with the focus point aimed at your son's eye. When you have a crisp sharp focus don't stop. Focus even closer until the focus just starts to look a tiny bit fuzzy. You may need to experiment by taking a few shots at slightly different focus settings until you get exactly what you want.

The problem is that your X90, even at F/4, probably has a large enough depth of field that everything say 1,5 metres in front and 1,5 metres behind the target is in sharp focus. By using manual focus you can shift that "focus zone" forward so that everything 2.5 metres in front and only maybe 0.5 metre behind is in focus, helping to blur the background.

Step 6: Take the shot and then press the viewing button and enlarge to check if the image of your son is sharp and the background is out of focus as you want.

The more you experiment, the better the results you will get. Its not an easy or quick process but once you get used to it you can preset some of the settings. Good luck.

If you have the facility you can probably get a good result using post processing software. On-One Software's FocalPoint does a nice job if you are careful.

10-24-2011, 12:22 AM   #5
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Hi!

Unfortunately, I did not notice that the camera is point and shot camera not DSLR in my first post. So my recommendations were not relevant very much.
I recommend to try some online DOF calculators, for example, Online Depth of Field Calculator
They will allow understanding how wide the DOF for this camera is, especially in wide angle. For example, if one seta focal length to the widest angle - 4.6 mm (26 mm in 35 mm film equivalent), aperture at F2.8 and focus the camera the target 2 m away, both the target and every background will be quite sharp because the hyperfocal distance will be only 1.5 m. So both the target and background will fall in DOF zone. The DOF will start 0.86 m from camera (the near limit) and will continue until infinity. If one chooses focal length 23 mm or 130 mm in 35 mm film equivalent (5x zoom), then at F4.0 the near limit will be 1.86m, the far limit will be 2.16 mm. So the length of DOF will be quite shallow – 0.61 m. Theoretically, it will be possible to get the sharp target but blurred background.

I would like to point out that in the DOF calculator you should input real not 35 mm equivalent focal length. Otherwise the result will be incorrect.
05-04-2012, 01:22 AM   #6
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hi when i open the x90 tells me to take off the cover the lens, remove the lid does not open and what to do;
05-06-2012, 01:37 AM   #7
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QuoteOriginally posted by tasos vita Quote
hi when i open the x90 tells me to take off the cover the lens, remove the lid does not open and what to do;
Hi Tasos.
When you press the power on/off button on the X90 the lens extends to its previous zoom position.
This means you must remove (take off) the lens cap BEFORE you power on the camera.

So:
  1. Read the Instruction Manual on the CD that came with the camera
  2. Insert a SD card into the camera
  3. Insert a fully charged battery into the camera
  4. Remove the lens cap
  5. Power the camera on by pressing the power button (green light comes on)
  6. The lens should extend
  7. Set the mode dial to green "AUTO PICT"
  8. Point the camera at something
  9. Press the shutter button half way down and allow the camera to focus
  10. Now press the shutter button full down and take a picture

Congratulations - you have taken your first photo with the X90

Sit with your camera and the Instruction Manual. Read about the different settings and then do it on the camera.
You should soon be familiar with everything.

Good luck
05-10-2012, 11:37 AM   #8
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ok thanks !!!

07-24-2012, 08:13 AM   #9
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Wow.........I just joined the Forum and mainly use my Kx, but I bought an x90 about a year ago..............its not even listed in the camera reviews

Is the X70 and X90 like "those whom we do not speak of "???............................admittedly the image quality is not great, but it does have some excellent characteristics, like its Macro mode and flash which seems to work well, plus a great zoom length. I find that it automatically chooses auto ISO and will readily swap to 800 or above, where it really suffers.
08-03-2012, 10:31 AM   #10
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Hi Robbod
Apart from myself there were quite a lot of X90 owners on the forum and quite a few excellent X90 images have been posted. I find it a very good carry-around camera. Its quite light and small enough but has great reach for birds and other subjects where you just can't get close enough.
You can set the ISO to auto and then limit the range. I set mine to 80 - 400 and then over-ride manually if I really need higher.
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