F Number frustration

kira

kira

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Kira
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Hey

Firstly.... I have a Canon 400D and a 50mm F1.8 lens

I am struggling to understand what I am supposed to do.... I want to take photo's of either 1 person or 4 people or a flower or a whole scene. Whatever it is I can never seen to get anything to focus like I want it too! I want my image to be crisp and it just looked blured/out of focus every single shot!

I have picked up that F1.8 means the lens is wide open and F22 means it's fairly closed, also that the aperture for these is the F1.8 doesn't need a lot of light so aperture could be 1/200 for example but an F22 would need a higher number like 1/2000

Am I sort of right so far?

What I am really confused with is that what F number should you have it on if you want to get say a family of 4 all in focus?

As I seemed to think that F1.8 had everything in focus and say F22 would have a minimal amount in focus but it seems no matter what I do I am not getting any kind of positive result and I don't know what I'm doing wrong!

Is it better also to use a tripod when taking portraits?

Anyone that can help/offer advice I would be really grateful! Thank you

Kira :)
 
Right principle, wrong way round - F1.8 has less in focus and higher shutter speed 1/2000, F22 has everything in focus and much lower shutter speed say 1/20.
 
Is all about Depth of Field when talking about Aperture. Once you understand Aperture and Depth of Field everything will start to make sense.

Using F1.8 means you only focusing small part of the scene. Try increasing the number and you will focus more on the scene.

Try F8-11 because it find it the sharpness is good and it can capture the whole scene as well.
 
Alan Clogwyn said:
Right principle, wrong way round - F1.8 has less in focus and higher shutter speed 1/2000, F22 has everything in focus and much lower shutter speed say 1/20.
Click to expand...

+1!

The lower the f-number, the more light is getting through it and the shallower the depth of field (although depth of field is also dependant on focal length and distance to the subject).

As a rough guess, with a 50mm lens you'd need f5.6 or greater to get everyone in focus.

A good idea would be to set you camera to AV mode, dial in f5.6 and let the camera work out the shutter speed with your ISO set to auto.

Bear these settings in mind and then you can try altering them in Manual, if the depth of field is the most important thing, the next most important thing is the shutter speed, you want that as high as you can go to stop camera shake/motion blur but not so high that you have to shoot at ISO1600 in daylight ;)
 
Here’s an example.....

Your are taking a shot of a subject which is around 2m away. you have the fstop set to 1.8
You focus range on the subject is around 10cm anything out of that foreground or background will start to focus out (blur)

Now if you stay the same but up the f stop to say 5.6 your focus range is now around 34cm. Again anything out of that foreground or background will start to focus out (blur)

That’s how I understand it anyway...if that s correct.
 
This might help, it's an interactive site where you input the shutter speed, aperture etc and it shows you the effects of altering the different settings :thumbs:
 
kira said:
Whatever it is I can never seen to get anything to focus like I want it too! I want my image to be crisp and it just looked blured/out of focus every single shot!
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Could be a bit of camera shake creeping in here. If a slow shutter speed is selected, lower than around 1/125 you need to brace the camera and prevent movement as much as possible.
 
Also as a rule of thumb(before anyone buts in with stabilisation or crop sensors;)), use a shutter speed at least that of the focal length of the lens.

ie. If you're using a fixed focal length lens of 50mm you'd be looking for a shutter speed of 1/50 of a second to prevent blur from an unsteady hand. In the end it's all a big juggling act depending on the amount of light available. That's why you'll hear of people using Neutral density filters to cut the amount of light or alternatively using flash to increase it. I know it sounds complicated, and for the beginner it is, but with practice you'll begin to understand it all.:thumbs:
 
Hi Kira - we're hoping to have a photo walk sometime in August in the Hampshire area. Normally there's a friendly, helpful group of about 10 / 12 of us - all ages, all abilities.

If you would like to join us for a couple of hours on the photo walk you would find it invaluable to discuss and experiment with your camera settings with lots of similarly minded people around you.

Once we've decided on a date - I'll post the details in the forums. Have a look under "Everything Else - Meeting Place" and see what's there.

As a group we've been to Old Portsmouth; Winchester; Lacock; Reading; Bosham; Emsworth; Chichester and Alresford and we've all returned with big smiles on our faces. The New Forest is one the options we are currently considering for our next meet.

Hands on experience is a great way to learn and experiment with your camera.
 
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Also as a rule of thumb(before anyone buts in with stabilisation or crop sensors), use a shutter speed at least that of the focal length of the lens.

When you get to my age, 68, use ISO 400 minimum, 1/500 minimum, monopod, tripod, bean bag all together :D and anything else you can come up with to prevent camera shake. :D

If possible I then rope the whole lot to a lamp post, me included and this is WITH VR.

D in W
 
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how i think of aperture is akin to a bucket and funnel and paint,

if you pour paint in a bucket straight from tin, the paint being light, it will splatter all over side of bucket, = f1.8
if your pour paint through a funnel it will go in more smoothly and not splatter so much = f.22,

bigger f number smaller aperture,
smaller f number bigger aperture

and main things, experiment, observe, and pratice,

and stick with TP
 
I had/have trouble with the concept of aperture vs DoF, I have to think like this:
Small f-number = big hole = small DoF
Big f-number = small hole = big DoF

So to get what i want I have to think "small-big-small"
Its a bit basic but works for me.
 
rhody said:
Hi Kira - we're hoping to have a photo walk sometime in August in the Hampshire area. Normally there's a friendly, helpful group of about 10 / 12 of us - all ages, all abilities.

If you would like to join us for a couple of hours on the photo walk you would find it invaluable to discuss and experiment with your camera settings with lots of similarly minded people around you.

Once we've decided on a date - I'll post the details in the forums. Have a look under "Everything Else - Meeting Place" and see what's there.

As a group we've been to Old Portsmouth; Winchester; Lacock; Reading; Bosham; Emsworth; Chichester and Alresford and we've all returned with big smiles on our faces. The New Forest is one the options we are currently considering for our next meet.

Hands on experience is a great way to learn and experiment with your camera.
Click to expand...

This sounds really good, thank you for letting me know!
 
I had a little practice yesterday and I could see the results of changing the F number so I think I know roughly now what they all do....

But when I see all the other areas and photography talk my heart just sinks as I just think I do not get that or it just seems too hard to understand sometimes.

I still think I need a better camera and lens for more crisp photo's, I know I'm probably comparing myself too much to say someone that's got a £2000 camera but I'm just getting frustrated as I've had quite a few people ask me to take some photos for them and I'm just not happy to do it because I look at these people who go on these photo shoot days and pay like £300 for 10 shots and mine do NOT come out like that and I feel like mine are really bad for not being Crisp enough.

I've never used a tripod, I find them really awkward but do you think maybe this is the way forward? Or do I need some sort of software to make the image sharper? Any advice is well and truly appreciated as I've got 2 families wanting some photos done and I would really love to do it but I just don't think I can...... =(
 
kira said:
I had a little practice yesterday and I could see the results of changing the F number so I think I know roughly now what they all do....

But when I see all the other areas and photography talk my heart just sinks as I just think I do not get that or it just seems too hard to understand sometimes.

I still think I need a better camera and lens for more crisp photo's, I know I'm probably comparing myself too much to say someone that's got a £2000 camera but I'm just getting frustrated as I've had quite a few people ask me to take some photos for them and I'm just not happy to do it because I look at these people who go on these photo shoot days and pay like £300 for 10 shots and mine do NOT come out like that and I feel like mine are really bad for not being Crisp enough.

I've never used a tripod, I find them really awkward but do you think maybe this is the way forward? Or do I need some sort of software to make the image sharper? Any advice is well and truly appreciated as I've got 2 families wanting some photos done and I would really love to do it but I just don't think I can...... =(
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Kira, a tripod is probably the second most important bit of kit you'll ever buy, and the thing that most people resist spending the money on. It's also the single biggest aid to getting sharp images. It's not essential in all honesty if you can get a fast enough shutter speed for hand holding, but I rarely go anywhere without my tripod - and never for the bird photography I do the most of. Yes - it's a pain to lug a tripod around, but getting the right one can make all the difference both to weight, stability and ease of operation. Don't go and buy just the cheapest tripod you can find - you'll definitely regret it.

The other thing is that post editing is an essential part of the process of getting sharp images. Don't expect your images to look razor sharp out of the camera - many images which don't look quite sharp enough are easily sharpened up in post editing. It's a racing certainly that those images you're casting an envious eye over at the moment have had a fair bit of editing - including sharpening.

Take your time gal - you're obviously dead keen and I can feel your frustration. You have a bit of a hill to climb but plenty of people have climbed it before you and it's not as steep as you think. ;)

EDIT.

There's nothing wrong with your 400D by the way - it's more than capable of producing the results you're after.
 
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Dave in Wales said:
Also as a rule of thumb(before anyone buts in with stabilisation or crop sensors), use a shutter speed at least that of the focal length of the lens.

When you get to my age, 68, use ISO 400 minimum, 1/500 minimum, monopod, tripod, bean bag all together :D and anything else you can come up with to prevent camera shake. :D

If possible I then rope the whole lot to a lamp post, me included and this is WITH VR.

D in W
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You too? :lol:
 
kira said:
Do you have any suggestions on what software to use?
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It's not really that important Kira - the main thing is to pick a package and stick with it for a while. Chopping and changing, especially in the early stages can get very confusing, as different packages use different terms for the same thing.

Photoshop elements is a good bet - it will enable you to do pretty well anything you need to without spending a fortune. The biggest argument in favour of any version of Photoshop is that they're used by the vast majority of users and you'll find more people on line who can help you if you need it.

There are plenty of other excellent packages, but the users tend to be a bit thinner on the ground when you need help.

You can get 'The Gimp' free on line - I've never used it but it's supposed to be good. You can also get free downloads of evaluation copies of various software on line if you do a search. Paint Shop Pro is one that lets you do free downloads., but there are others if you have a look.
 
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The Canon DPP is probably good enough for the basic RAW processing. A little bit more advanced stuff with layers etc GIMP is a good package.

I use both and although I am no expert, I have yet to find anything missing using that combination. I'd start with those two packages.

GIMP and Photoshop processes are quite similar at the basic level. You can usually read a Howto for Photoshop and basically transfer the instruction to GIMP.

Andy
 
Kira - Currys have Photoshop Elements 8 on sale at the moment for about £10. I got it today - there were none on display in my local Currys but when I asked they had one. (Thanks to someone on here for flagging that one up!)

Its all a bit overwhelming at first, but you will get to grips with it. Going out for the day with other photographers is a great way of learning.

Practice loads - take shots at different settings and see the difference. Play about with post processing. You'll make mistakes, but you'll learn from them. Every time I feel frustrated at how much there is to learn, I look back and see what I've learnt already. This time last year I had no idea what focal length or aperture was...
 
ShoeQueen said:
Kira - Currys have Photoshop Elements 8 on sale at the moment for about £10. I got it today - there were none on display in my local Currys but when I asked they had one. (Thanks to someone on here for flagging that one up!)...
Click to expand...

Thanks for the "heads up" ShoeQueen (are you relatedd to Mrs Oggy by any chance?). I'll be thhere tomorrow. :thumbs:
 
ShoeQueen said:
Kira - Currys have Photoshop Elements 8 on sale at the moment for about £10. I got it today - there were none on display in my local Currys but when I asked they had one. (Thanks to someone on here for flagging that one up!)

Its all a bit overwhelming at first, but you will get to grips with it. Going out for the day with other photographers is a great way of learning.

Practice loads - take shots at different settings and see the difference. Play about with post processing. You'll make mistakes, but you'll learn from them. Every time I feel frustrated at how much there is to learn, I look back and see what I've learnt already. This time last year I had no idea what focal length or aperture was...
Click to expand...

Thank you for that! I will have a look :)
 
Oggy said:
Thanks for the "heads up" ShoeQueen (are you relatedd to Mrs Oggy by any chance?). I'll be thhere tomorrow. :thumbs:
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IIt was another TPer who pointed it out so thanks should go to them - http://www.talkphotography.co.uk/forums/showthread.php?t=336521

My local Currys had sold out of the Elements 8 for £9.95 but had Elements 8 bundled with Premiere 8 (which I think is for video editing) for £14.95 so I took that. And they didn't have it on display or on the shelves - I asked someone to check for me as I'd seen it on here she went and found one for me. I think it just depends on what each store has left in stock.
 
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wallyboy said:
how i think of aperture is akin to a bucket and funnel and paint,

if you pour paint in a bucket straight from tin, the paint being light, it will splatter all over side of bucket, = f1.8
if your pour paint through a funnel it will go in more smoothly and not splatter so much = f.22,
Click to expand...

:thumbs:


Splattering up the sides of the bucket equals out of focus stuff.
Pouring though a funnel will be neater, however it takes longer and needs more shutter time.
 
kira said:
Do you have any suggestions on what software to use?
Click to expand...

Be careful. Digital images can appear soft (photographer speak for slightly out of focus) but this is not because they are out of focus it is to do with the way the image is recorded on the sensor and can be corrected in software using the 'sharpening' option. This option will not bring an out of focus image into focus.

You need to keep practising with Getting the ISO/aperture/shutter speed combination correct for the image you want to take.

Put rather simply

Shutter speed will help stop movement (yours or the subjects).
Aperture will control how much is in focus front to back ( called depth of field)
ISO. will control how sensitive the sensor is to light and give you more flexibility with aperture and shutter speed

Now you just have to practice. Go out and take pictures of anything and everything.

In the old days of film, when you opened the film box there was a sheet of paper which gave you the correct aperture and shut speed for different conditions the film with that ISO

so a sunny day with 100 ISO film was 1/125 at f8

And you got good results.
Cloudy was 1/125 at f5.6 or possibly f4

Really swanky photographers had light meters but for most circumstances the suggestions on the little bit of paper worked fine.
Try and keep it simple to begin with and just take loads of photographs. You have an excellent camera which will give you excellent results.
 
kira said:
Thank you for that! I will have a look :)
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thats a bargain, i paid £50 for elements 9, the only difference is 9 has a layer mask, i also bought this
Forbiddenbiker said:
:thumbs:


Splattering up the sides of the bucket equals out of focus stuff.
Pouring though a funnel will be neater, however it takes longer and needs more shutter time.
Click to expand...

:thumbs:
 
Oggy said:
Thanks for the "heads up" ShoeQueen (are you relatedd to Mrs Oggy by any chance?). I'll be thhere tomorrow. :thumbs:
Click to expand...

Hmmm. Think I will be looking at keyboards too. :shake:
 
The F. numbers made much more sense when i found out what they meant.
F.Number = Focal Length/Aperture Size.
So with your 50mm: F.Number = 50/Aperture Size
Or rearranged: Aperture size = Focal length/F.Number.
Having a large aperture of say 28mm gives 50mm/28mm = F1.8
This is how the larger aperture gives a smaller F number. The bigger the aperture more light can get in so a faster shutter speed is needed.
For a smaller aperture F8 (F8 = 50mm/Aperture) the aperture size will be 6.25mm. Bigger F number has a smaller aperture so it will need a longer shutter speed to let enough light in.
The equation above works for different length lenses. A photo taken at a given F., shutter speed, iso etc should give the same exposure using different lenses. (There will be some variation as lenses lose some light as it passes through, search T-Stop if you're feeling technical...)
 
I'm a bit of a newbie to all of this too and everyone's ways of explaining things has been really useful. I went on an adult ed course last year and found that I had hardly learnt anything, as they didn't explain things simply!! So thanks everyone!!!
 
Greywolf said:
Be careful. Digital images can appear soft (photographer speak for slightly out of focus) but this is not because they are out of focus it is to do with the way the image is recorded on the sensor and can be corrected in software using the 'sharpening' option. This option will not bring an out of focus image into focus.

You need to keep practising with Getting the ISO/aperture/shutter speed combination correct for the image you want to take.

Put rather simply

Shutter speed will help stop movement (yours or the subjects).
Aperture will control how much is in focus front to back ( called depth of field)
ISO. will control how sensitive the sensor is to light and give you more flexibility with aperture and shutter speed

Now you just have to practice. Go out and take pictures of anything and everything.

In the old days of film, when you opened the film box there was a sheet of paper which gave you the correct aperture and shut speed for different conditions the film with that ISO

so a sunny day with 100 ISO film was 1/125 at f8

And you got good results.
Cloudy was 1/125 at f5.6 or possibly f4

Really swanky photographers had light meters but for most circumstances the suggestions on the little bit of paper worked fine.
Try and keep it simple to begin with and just take loads of photographs. You have an excellent camera which will give you excellent results.
Click to expand...

I like this post :thumbs:
I'm still trying to practice and they are still not as sharp as I want them.
I'm looking after a 2 year old who moves around like crazy and trying to get a smiling face shot, indoors with a tripod is just proving impossible!

Any more tips on this situation pleaseeeee :shrug:
 
kira said:
I'm still trying to practice and they are still not as sharp as I want them.
I'm looking after a 2 year old who moves around like crazy and trying to get a smiling face shot, indoors with a tripod is just proving impossible!

Any more tips on this situation pleaseeeee :shrug:
Click to expand...

Hi Kira - high speed 2 year old's indoors - they are always a challenge.

If you up your ISO to at least 400 and choose a location with good even light (not too strong), near a window or patio door perhaps and experiment with the wider apertures (smaller f numbers) on your camera you will start to get the images you are after and you won't need a tripod at all.

A wider aperture will blur the background and concentrate the viewer on the child as the main subject instead of a busy or cluttered background.

Why not practice on a large teddy or something first? It won't move and you can practice and experiment to see what happens when you make changes to your camera settings and make changes to how light is falling on your subject.

If you practice with a large toy - the child will almost certainly become curious and want to be involved and you could end up with some super candid shots, smiling faces and catch lights in the eyes.

And speaking of eyes - always focus on the eyes and your portraits will come alive.

Try and get down to their eye line when taking the shots - it avoids looking down on them - and gives a more powerful image. Also - use a long lens if possible - it gives them some space to move around without you being "in their face"

If you use flash - try bouncing it off the ceiling to avoid harsh light and red eyes in your subject (should be OK with the teddy though)

You will get some great shots - especially when the child is relaxed in front of the camera.

There is a great book by Annabel Williams "99 Portrait Ideas" which you may find very useful - it is full of practical tips and ideas - especially when it comes to photographing children. It was on the shelves in Asda last Christmas at a very good price and is also being sold by Amazon.

Happy shooting
 
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Hi Kira and welcomed to the wonderfull world photography :D

Can offer a few thoughts for you?

1) You have had some really good pointers about how the aperture affects the Depth of Field and thus with in your example say a family of 4 are standing in a group where the nearest one is say 10feet from you and the furthest is sya at 13feet ~ one would expect the whole group to be in focus with an aperture of around f8

1a) Do not be tempted by using a technique called "focus & recompose" by this I mean if the group are say two adults and two children the height of the kids means that their heads are at approx waist height and you focus on the kids faces and then recompose to make sure you have the adults faces in the frame nothing will be sharply focused!

2) As a rule (mentioned above) with your 50mm lens the minimum shutter speed to you is 1/50s however note I say minimum ~ because of your newness to the SLR world you should be working with a min of say 1/200 (more chance catching that moment of the racing 2 year old :lol: )

2a) If indoors and at say f4 and needing 1/200 the camera will not let get those sort of settings then raise the ISO as much as needed..........ISO 1600 if needed??? For the record indoors photography with only natural light is very challenging even for the best photographers.

3) Please, please do not equate more expensive cameras & lenses with better images ~ if anyone anywhere should ever tell you that run a mile. Camera handling methods & technique are what produce in focus, well exposed, well composed appealing images i.e. the user not the price you paid for the gear ;) The only time you should consider spending more money is when you have found the limitations of the camera body and/or need other lenses for specific types of photography such as 100-400 zoom for wildlife & airshows or the 10-22 zoom for landscapes.

4) You are rightly and correctly asking for advice and that is good that you are willing to listen & learn but so far all the advice has been general tech & camera handling ~ as soon as you are able do get say a Flickr account and show some of the pictures you are trying to describe as 'out of focus....' without seeing specifically what you are trying to describe the advice can only be vague and general.

5) The software that came with the camera should in the first instance be more than adequate for viewing and making them web sized to show us ~ Photoshop Elements and other software will take you to any next level as you may need once over the fisrt hurdle of learing how to get the picture right in the camera to start with.

6) Oh, not to forget practice, practice, practice..............and did I say practice. The greatest tool for learning what each setting does if to see the effects of chaning the aperture/shutter speed & ISO and that is not best achieved running around after a 2 year old. I would suggest a garden of even the brickwall of your own house???
 
Russ77 said:
+1!

The lower the f-number, the more light is getting through it and the shallower the depth of field (although depth of field is also dependant on focal length and distance to the subject).

As a rough guess, with a 50mm lens you'd need f5.6 or greater to get everyone in focus.

A good idea would be to set you camera to AV mode, dial in f5.6 and let the camera work out the shutter speed with your ISO set to auto.

Bear these settings in mind and then you can try altering them in Manual, if the depth of field is the most important thing, the next most important thing is the shutter speed, you want that as high as you can go to stop camera shake/motion blur but not so high that you have to shoot at ISO1600 in daylight ;)
Click to expand...

You can't set ISO on auto in the op camera
 
Box Brownie said:
4) You are rightly and correctly asking for advice and that is good that you are willing to listen & learn but so far all the advice has been general tech & camera handling ~ as soon as you are able do get say a Flickr account and show some of the pictures you are trying to describe as 'out of focus....' without seeing specifically what you are trying to describe the advice can only be vague and general.
Click to expand...

I have a Flicr account with 6 photos on there so you can have a look :)

http://www.flickr.com/photos/kira_farrow
 
Hi Kira,

I think what people on here have said about the technical aspects is spot on but I would add that one of the hardest things to do with photography is to have patience... Most of us have been using a camera for many, many years and some like me have done courses for a few years too. But even with all this we will still get some pictures that are out of focus and just plain bad. Sure, with experience comes a higher percentage of good shots, but please don't beat yourself up about pictures not being as sharp or as good you would like. In some ways it is easy to take pictures, but it is very difficult to take good photographs. That comes from learning about aperture, shutter speed, iso and composition. The problem with photography is that you'd think it should be easy to do, you just point it in the direction you want and then hit the go button. And sometimes this works. But 99% of the time it is in fact REALLY hard to do well, especially when you first start out. I know there are lots of terms that seem bewildering but they will honestly come. The most important things to understand at the moment is aperture, shutter speed and iso and their relationships together. Once you have that you'll find you pictures improve 1000%.

In my mind, one of the very best places to get more of an idea of the technical aspect is this through guy, he is fantastic at explaining things in a human way. http://videos.ppsop.com/index.html

If you sign up to his page you can see quite a few videos and they are very, very good. Apart from that, give yourself time. It will come. :thumbs:

Just seen your flickr pictures. I can see what you mean about the sharpness but I have a feeling it is from a combination of things (a) where you have selected to focus (b) it possibly being too shallow and (c) the shutter speed not being fast enough. Mistakes we can all make.

The biggest thing I would say is that those pictures have a lot going for them in many ways as you obviously have the 'eye' for photography and THAT is the hardest part of it. Anyone can get technically proficient, but those that take the best pictures are the ones that see shots that others don't. So really, stop beating yourself up so much as I think you are well on the way to becoming a good photographer!
 
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