Clarification Sought

The_Oakster

The_Oakster

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Ben
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I received a Panasonic Lumix FZ45 for Christmas and I am completely new to photography so I am more than happy with the camera. However...

I am looking into the full ins and outs of how to use it and how to take a good photograph. I purchased "Understanding Exposure" as it seemed to be the best beginner book by recommendation.

I was following the book quite happily and was impressed by the ease of which the points are explained. I was playing with my camera as I went along and then after getting to page 54 it then said that for fixed lens cameras (like mine) shooting at f2.8 is the same as f11 on an SLR and at f8 its the same as f32 on an SLR.

I'm not going to rush out and buy a new camera, I'll learn with what I've got, but I need to know what limitations that puts on me and what it means as I continue to read through the book?

I can understand that by only having f11 I will never get the right depth of field for blurred backgrounds. Is that what I lose with this camera; am I going to have to take more landscape style shots than close ups?

Alos, my lens according to Panasonic is equivalent to 25mm-600mm in 35 mm standards. What does that mean for the type of photographs I can take too? Or is that reflected in the above questions?
 
The approx fnumber is all about the depth of field, but you should take that figure with a pinch of salt. I don't often handle compacts, but at the long end of the zoom you can generally get an out of focus background in a portrait.

As far as focal length goes, that's a handy zoom and a set of lenses for a modern crop DSLR would mean you buying lenses from about 18-400, which even with cheaper lenses is more than a the camera body will cost. Think carefully before you jump into this, it's a money pit.
 
As the sensor in a camera gets smaller the depth of field gets bigger, so f2.8 on your camera may produce photos with a depth of field similar to f11 on an SLR.

Possible solutions are, as Phil has suggested, take photos with the zoom set towards its top end, - not always possible and there is the greater chance of introducing camera shake.

Try to have the subject well away from any background - again not always possible.

One area of photography that won't have a large depth of field is any macro work you do.

The zoom range you have will allow you to take fairly wide angle shots and get some close ups of distance objects. My fz28 has a shorter zoom range but produces decent enough shots at the 35mm equivalent of 480mm. Not in the same league as a DSLR with a telephoto, but for that the lens alone would have cost many times what I paid for the fz28.

Dave
 
I took the following at a gig by Ocean Colour Scene in Lincoln in 2008 and not the greatest of pictures. It was taken on a Panasonic FZ30 at f3.6 at 1/30/sec and ISO 80 at 360mm FL and as you can see the guy in the background is blurred. Maybe not the greatest of pics but it does give you an idea of the DOF you can get. You wouldn't get the background blur at around f15 with a dslr so I wouldn't worry about what the numbers in the book says too much.

6646532609_235a269f30_z.jpg
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You will have great difficulty getting shallow depth of field effects with that camera, compared to cameras with a larger sensor.

It has a 25-600mm equivalent lens (compared to full frame) but the actual focal length is 4.5-108mm. So if you divide one into the other, you get a crop factor of 5.5x, which is even higher than the 4x figure used in the book.

To get the equivalent in depth of field terms, multiply the f/number by the crop factor, ie, f/4 is equivalent to f/22 in full frame terms.
 
Ah I see, so it's worth me carrying on with the book then. I just have to think that although I'm not limited to what shots I can take I won't get shallow DoF effect. Other than that I should be okay?
 
The_Oakster said:
Ah I see, so it's worth me carrying on with the book then. I just have to think that although I'm not limited to what shots I can take I won't get shallow DoF effect. Other than that I should be okay?
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Yes, just keep the ISO down. Again because of the small sensor, it can't collect much light so at high ISO it will get rather noisey - grainy images with less shadow detail. If you get that, don't print those images too big and it won't be so noticeable.

Edit: on the shallow DoF thing, to maximise that, use a longer focal length and lowest f/number. Keep the subject as far from the background as possible, and really fill the frame. That will at least put the background out of sharp focus even if it won't go to a completely abstract blur, and make the main subject stand out.
 
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Some compact manufacturers recognise the DOF problem and offer a preset shooting mode which simulates it. Read your camera's handbook carefully, you might find something there.

My Fuji Finepix F72 handbook calls it Pro Focus Mode, and says the camera takes up to three pictures and combines them to give an out of focus background.
 
I dont seem to have that option Stratman :(

As for the ISO point, I took the following portrait of my son to get the blurred background but left the camera on auto ISO and it took it at 1600 and I can see the 'noise' on it. What should I set the max too? The pis is unedited other than cropping.


The Boy by The_Oakster, on Flickr
 
You say you're letting the camera set the ISO, you were shooting Manual, you should let the camera help you out in the right direction here.

I've no idea what the max aperture of the lens is, but if you'd set your ISO at 400 and left the aperture where it was you'd have a shutter speed of 1/125. That would probably be noise free. You could possibly have a wider aperture and a higher ISO or faster shutter speed too with a wider aperture.

Setting the camera on Manual and twiddling the Shutter speed and Aperture dials until the meter centres isn't really helping you learn. If you're interested in finding the limits of your control of Depth of Field, use Aperture Priority, and set your ISO yourself.

It's not so obvious if you never used film, but if you think that most people only ever used 200iso film, and sometimes 400 in the winter, you have a starting point. So they're your 'go to' ISO's for outdoor shooting. So if you try to stick with 100-200iso in summer and 400-800 in winter, don't change them till you can't get what you want.

When shooting indoors, if you want to take advantage of ambient light, you'll then appreciate that you're stretching the boundaries of what's photographically possible and be happy with a 'noisy' picture, because in the past the picture would have been impossible.

We're spoilt with our new fangled digital cameras giving us an infinite choice of ISO. But it muddies the choices in ways you don't need. I'll assume the book doesn't take into account auto ISO, because it was written in Film days it'll assume a fixed ISO.
 
Thanks Phil. The book does talk about ISO but I havent got to the specific chapter so I dont know if it talks about auto ISO or not but the rest of the book (3rd edition) has a lot of the digital camera settings so it may do.

So when I am trying to get an adequate depth of field I should shoot in Aperture Priority mode but I should shoot in Manual at other times to get to know how a photo is taken and not just really on the 'intelligent AUTO' setting to do everything for me?

As for maximum apperture according to the Panasonic specs sheet its says:

Aperture F2.8 - 5.2 / Multistage Iris Diaphragm (F2.8 - 8 (W) / F5.2 - 8 (T)) / (F2.8 - 11 (W) / F5.2 - 11 (T) in movie recording )
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Does that make it clearer to you :thinking:
 
Brutally Honest, I'm far from a fan of the 'Manual is the only way of doing it properly' school of thought. :)

You've already been tripped up by it because you've been convinced of the importance of Manual, before you've got an understanding of exactly WHY. Unfortunately, this is a common occurrence which is almost becoming a trend. You chose Auto ISO and Manual - which isn't really Manual at all:(.

Ignore Intelligent auto, and Auto ISO, these will both lead you into places where you'll not get an understanding of what's happening and why.

Until you've read enough of the book to get a full understanding of how exposure and metering works, use Program or Aperture Priority and enjoy taking pictures. Using my ISO guidance from above. Concentrate on learning how to read all that's in your frame and focussing on what's important in that frame, everything else will come with time.

As far as your maximum aperture is concerned - no it's not clear. The problem is that the maximum aperture is variable on your lens, so at it's widest setting the maximum aperture is 2.8 and at the longest telephoto setting it's 5.2, so at any given focal length it will be a different number. So it was probably at Max aperture on your sample.
 
Thank you for your time and help Phil. Ill keep clicking away and like you say, as time goes on, I'll start to notice the difference that each setting makes.

Until I get a DSLR (which wont be for at least a year unless I have an unexpected inheritance cheque on its way) I'll learn what I can with what I've got :D
 
Tringa said:
As the sensor in a camera gets smaller the depth of field gets bigger, so f2.8 on your camera may produce photos with a depth of field similar to f11 on an SLR.
Click to expand...

No. DoF is a fucntion of the optics and camera to subject distance and is not affected by sensor size although the sensor size could well (or even probably will) influence what optics you use and perhaps even your camera to subject distance and thus indirectly affect DoF.

When thinking about compact camera lenses and their equivalent DSLR focal lengths we must never forget that a 6mm lens is always a 6mm lens and will always have the optical properties of a 6mm lens even when we like to think that it gives the same field of view as a 50mm lens.

When using a compact camera if you want to get some control over DoF and some shallow DoF you're probably going to be best off using the widest aperture possible and the longest focal length whilst getting your subject closer to the camera and the background further away. It isn't always easy or even possible but with some compacts with relatively wide apertures it is sometimes possible with thought.
 
The_Oakster said:
Thank you for your time and help Phil. Ill keep clicking away and like you say, as time goes on, I'll start to notice the difference that each setting makes.

Until I get a DSLR (which wont be for at least a year unless I have an unexpected inheritance cheque on its way) I'll learn what I can with what I've got :D
Click to expand...

Yup. The best way to find out what is possible is to try the different settings with different scenes. Shooting digital is cheap so firing off some test shots shouldn't break the bank.
 
I am managing to get some DoF but not to worry, if it's not what my camera does well then I'll concentrate on what it can do and I'll have something new to learn when I get a camera and lens that does it well :D
 
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