Hi, Milen.

I have the S1600 which is basically the same camera. I have also found that on full zoom when videoing that the focus comes and goes. I tend not to put it on full zoom now. I can't help you with the still shots but I'm sure someone with more knowledge will be along soon. 

I have only just got my S1800 (well it is actually an S1900 but they are the same camera anyway).  In good lighting I only have the occasional out of focus shot. However .....

The first major project I needed the camera for was covering some concert type events i.e. Open air stage at nightime from very close to the front of the audience.   There were lots of flashing lights and "dry ice".  I would say more than 50% of the shots were out of focus.  The ones at a high zoom were the worst.  I tried the camera in various modes - I think I had the most sucess with "SR Auto" set to "Nightime" mode.

I am convinced the problem was focus (not shake) as the light levels were quite high.  If the camera had had a manual focus I would just have set it to "Infinity" and everything would have been fine I reckon, but it doesn't.

Can anyone offer any advice as to the best way to set up the camera for conditions such as I have described?  I really need a higher %ge of successful shots.

Thanks.

Hi, and welcome.  It's very easy to place the blame for blur on the equipment.  However, more often than not it is the photographer at fault.  Camera shake is the most common cause.  The more you zoom, the more this magnifies any movement, even though you may think you are holding the camera nice and steady.  Try looking through a powerful set of binoculars and see if you can keep the image still by just handholding them.  

If you can use a tripod, then do so, but remember to turn off any image stabilisation the camera has, or this may itself cause blur.  

If not, try and set a high enough shutter speed to avoid blur.  The rule of thumb for a sharp picture, free from the effects of camera shake, is to use a shutter speed which is at least as fast as 1 divided by the focal length of the lens. So if you are using your zoom set at 100mm you should use a shutter speed of at least 1/100 of a second. If you are using a 50mm lens you will get a sharp picture at 1/50th of a second.

Any camera except a few top end silly priced cameras will have trouble focusing in good light if the lens only has a maximum aperture of f 5.6. That is because the camera needs that aperture for a fast enough focus or to even focus at all. Even when shooting smaller apertures ,on the half press of the button the aperture is open fully right up to the time you press the shutter button fully home .

It is the raggedy edge of what's possible for fast focusing action shots where there is movement . For scenic pictures or where movement is relatively slow across the lens and the camera has time to settle it's focus down then it's fine.

Over short distances for closeups you could have more success than for distance shots .

To aid focus you should always .

Have the focus spot itself on a strong , sharp contrasting vertical . On a person in concert , a person's  eye next to the nose is ideal .

Most bridge cameras and compacts do not have cross hair type focusing sensors and do not focus well on strong contrasting horizontals . To get over that , shoot with the camera on it's side , known as shooting in portrait mode.

Do not shoot with the lens less than wide open with the aperture as it will be small enough as it is and any attempt to get a deeper field of view by reducing the aperture will just force the ISO  needed for correct exposure upward , making the picture grainier than it needs to be .

Even for a well lit concert photo you will need an ISO of at least 1600 for a strong spotlight on a performer if you are less then 60 feet from the stage unless you can drop your shutter speed down to 1/100s which would just be practical if you could keep the lens focal length of the lens below 70mm.

If you can keep the aperture at f 5.6 or below with a focal length of less than 200 mm you could use an ISO of around 800 to 1,200 and just about get away with a shutter speed of around 1/400s .

For each full stop of aperture you can successfully gain ( open up ) by getting closer to the stage , I would think you could reduce the reject rate by half.

F4 is an ideal aperture for concerts as first , the lenses of a lot of cameras can at least manage that and second , it gives a reasonable amount of depth if the focusing is slightly out.

Whether to turn image stabilisation on or off is a mute point . Some cameras will do better on way another camera won't .

I would try both to see which suites your camera best.

The half press of the shutter button in very low light such as concerts should be for at least two seconds before completion of a shot.

Remember that both on board flash and the focus assist lights are tend amount to useless at more than fifteen to eighteen feet so don't bother with either.

Avoid bland areas or small patterns at all costs for focusing on . They simply won't work .

With indoor lighting of any kind when guessing at how to take a picture , a nine out of ten is not a bad reject rate .

With practice and a bit of care you may get that down to about one in four .

Never expect the keeper rate to exceed that and take the amount of pictures needed accordingly .

The three hardest things that push a camera to it's limits or beyond are.

Focusing at extreme distances .

Focusing in low light.

Stopping fast action even in good light .

Add any one of those two things together and you are at the limits of what you can do with a lot of bridge cameras .

Add all three and you are possibly outside it's limitations .