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ricktas
03-10-2009, 8:38am
As it has been a while since we did this challenge, and we have had quite a few members join to learn how to use their shiny new camera's with more control over the results, it is time to give the NTP challenges another round.

Our challenge to our members that want to learn to take control of their digital camera is based on the Learning Centre topic : Experimenting with Aperture (http://www.ausphotography.net.au/forum/showthread.php?t=24050)

We would like you to set your camera to Aperture mode (sometimes called A or Av mode). Check your camera manual in need, on how to set your camera to Aperture mode.

We want you to go out and take two photos of the same subject. One at the largest aperture your lens will allow and one at the smallest. So take one photo at f4.5 (or larger - remember smaller F stop numbers are actually bigger apertures) and one at f22, of the same subject.

Post both photos in this thread, with comments about what differences you notice between the two photos , what the effect of aperture had on the shutter speed, and how you could use this difference to make your future photography more creative.

Looking forward to seeing the results and discussion.

bigdazzler
03-10-2009, 8:44am
You really do put a big effort into helping the newcomers to the game Rick .. for that you should be applauded mate, well done.

ricktas
03-10-2009, 9:01am
Thanks Darren. It is a bit of a balancing act, between encouraging new members to join in and learn, and also providing something challenging for the experienced members as well.

bigdazzler
03-10-2009, 9:12am
I bet it is .. the simplicity of these challenges is the key, both in as far as whats required to complete them and the way they are set out and explained. Id imagine thats gold for people that are totally new to all of this jargon that we throw around.

seastorm
03-10-2009, 10:19am
Thanks Rick, this is great!! Nothing like a challenge now and again to help speed up the learning process, I think of it like an exam or assignment :D

Now, to find a subject.....

bigdazzler
03-10-2009, 11:14am
Now, to find a subject.....

thats the thing about Aperture and DOF .. its one of the most basic fundamentals, yet arguably the most creative aspect of SLR photography .. you can make just about anything interesting by mixing it up

seastorm
04-10-2009, 10:32pm
Right-o, here's my contribution. I took 2 photos, one on f/2.8, and the other f/32. I thought I'd use a waterfall as my subject, that way the differences are very noticeable between the 2 apertures.

The photos are taken with my D40, Aperture setting, and the Tamron 90mm f/2.8 Macro lens.

Photo 1, f/2.8.
Photo 2, f/32. (Sorry Rick, I forgot it was supposed to be f/22, I just turned it to the max f. number allowed on my camera....)

I can see that in Photo 1, the shutter speed is very fast, hence the water drops are very noticeable, it gives the impression that the movement is frozen in time. Also the depth of field is around the water - the foreground and background objects are blurred. Because the shutter speed was fast (1/800 sec), the image was a bit on the dark side. To counter this, I would need to either slow down the shutter speed, or possibly choose a higher ISO?? (please correct me if I'm wrong here).

In Photo 2, just about everything in the photo is in focus, and the water looks like it's flowing, ie it gives the impression of movement. Because the aperture is on f/32 (ie small), the camera thinks it needs more light, so it slows down the shutter speed (down to 1/6 seconds). The depth of field is way much larger than with a smaller f number.

I would use a small f number (narrow depth of field) if I want to draw a person's attention to a particular area of the photo, ie bring out the subject a bit more to the viewer. A slower shutter speed give the impression of movement, and a fast shutter speed and large aperture to make everything crystal clear in the picture and freeze movement.

Kym
04-10-2009, 11:11pm
Dramatic difference! Excellent example of both DoF and shutter speed.

seastorm
05-10-2009, 12:15am
Excellent example of both DoF and shutter speed.

Thanks Kym!! :)

Hopefully my little contribution will help others as well, I tend to learn faster if I can see it rather than read about it :D

ricktas
05-10-2009, 6:21am
Good work. You mention slowing the shutter speed down for the first and raise the issue of changing either the shutter speed or the ISO. Increasing the ISO will increase the shutter speed even more. A higher ISO will counter a dark photo, given you keep the Aperture and shutter speed the same. Yes you can slow the shutter speed, but you risk an over-exposed photo then.

You have just discovered the exposure triangle. ISO / Shutter speed / Aperture are all inherently linked. Each one can be adjusted independently of the others, but all three need to be considered to get a correctly and creatively exposed photo.

seastorm
05-10-2009, 9:44am
Thanks, Rick :)

I think I'll need to do some more experimenting because I'm still a little bit unsure how ISOs affect a photo. :o

But yeah, with regards to the exposure triangle, it's one of those formulas (or is it formulae?) that photographers need to consider. I read somewhere that photography is a mix of art and science, I suppose this is the scientific part of it.

Kym
05-10-2009, 9:56am
I think I'll need to do some more experimenting because I'm still a little bit unsure how ISOs affect a photo. :o
But yeah, with regards to the exposure triangle, it's one of those formulas (or is it formulae?) that photographers need to consider. I read somewhere that photography is a mix of art and science, I suppose this is the scientific part of it.

This thread explains it. http://www.ausphotography.net.au/forum/showthread.php?t=24079
Post #2 of that thread shows the relationship in a diagram.

Back in the day ISO (aka ASA aka DIN) was the rating of speed of film (how reactive to light the film was).

In the digital they kept the same ISO scale and applied it to the sensor and the level of amplification of the sensor signal.

So a film camera set up with ISO 400 film, f/16, and 1/125 second exposure should produce an image print of very similar exposure (assuming default processing) to a digital camera on the same settings.

seastorm
05-10-2009, 10:05am
Thanks, Kym, I like diagrams, it helps me understand faster :D I will read up on it.

Cheers, all!!!

Actually, where are all the others? Please, please get involved and contribute to this thread, it will certainly help others and will definitely help you, I've learnt a bit more already!!! :th3:

wandera
06-10-2009, 10:21pm
Ok here goes, my first attempt at one of your challenges:
Both photos taken tonight about 5.30pm, at our fish pond water fall in our yard, home made pond & fall.
Camera Olympus E-410 First photo; F Stop f/4.2 Exposure time 1/60 sec iso was 1600 (opps didn't check that before taking photo) focal lenth 48mm Metering mode pattern
Second photo F stop f/22 Exposure 1/2 sec all other things the same.
I am facinated in the difference in colour & light between the two photos, I used a tripod & did not move between photos. so now let me learn what I did right & what I did wrong. thank you for this segment as I realy want to learn & don't have the funds to do a course
Keep up your great work it is appreciated

etherial
07-10-2009, 10:13pm
Somethings not right here, I wouldn't have expected such a huge difference in color between these two shots?:confused013

seastorm
07-10-2009, 10:56pm
There seems to be a lot of noise, I'd say due to the high ISO. Photo 2 also seems to be a bit overexposed.

Can somebody verify what I mentioned please, I'm still learning myself.. :)

ricktas
08-10-2009, 6:20am
Agree something else is going on here Deb. Cause you didnt include EXIF with your photos it is hard for us to tell what is happening. You mention ISO 1600 for the first photo, did you fix that for the second? If so, it is hard to compare the two. You will probably need to try again with the same ISO on both.

shaggydog
25-10-2009, 9:24pm
G'day,

I have been slowly plugging away at the aperture challenge for a while now. I'm a little frustrated (but not disheartened).
Maybe foolishly, I chose people as my subject(s). Unfortunately, although I am choosing to change only the aperture (as per the challenge), I find the camera often meters differently between shots.
I feel I need to have a better understanding of many more aspects of the camera than just aperture to be successfully completing this challenge (or maybe just choose a less dynamic subject and composure).
I'm really only posting this as I received an email from the forum telling me to post more messages. However I hope this makes some other struggling newbies feel a bit better too.

Cheers

ricktas
25-10-2009, 9:28pm
G'day,

I have been slowly plugging away at the aperture challenge for a while now. I'm a little frustrated (but not disheartened).
Maybe foolishly, I chose people as my subject(s). Unfortunately, although I am choosing to change only the aperture (as per the challenge), I find the camera often meters differently between shots.
I feel I need to have a better understanding of many more aspects of the camera than just aperture to be successfully completing this challenge (or maybe just choose a less dynamic subject and composure).
I'm really only posting this as I received an email from the forum telling me to post more messages. However I hope this makes some other struggling newbies feel a bit better too.

Cheers

Hey, firstly you dont need more understanding of your camera to do this challenge. That is the idea of the NTP forum, you learn one camera feature, then move onto the next and then start combining them. All the while learning what each function and part does.

Aperture affects depth of field, so if your people subjects are close to the chosen background etc, you will not notice as much variation as you would if they are several metres from the background.

Post some examples of what is happening and we can guide you on your way.

shaggydog
26-10-2009, 2:51pm
Thanks Rick,

I just managed to get something today that I think will show the DoF changes the aperture challenge is looking for. It will also (but not strikingly), show some of the problems I was mentioning...

I notice that even though the shutter speed automatically varies to account for the change in aperture, there still appears to be a change in the overall colour of the photo. I'm not clever enough to specify this change, but it seems like a slightly different exposure (on the wider aperture, the picture appears lighter than on the smaller aperture, even with the adjustment in exposure time).
Not seen in these pictures, as the lizard was very accommodating and sat still, is the introduction of motion artefact with smaller apertures (obviously due to longer exposure time). I struggle with this when taking pictures of people, but as you mentioned Rick, that's for another topic...

My camera: Canon EOS 50D
Lens: 24-105mm f/4L IS USM
For these pictures:
The constants: Focal length 105mm; ISO 400; flash not fired; hand held
Picture 1: Aperture f/4; Shutter Speed 1/2000
Picture 2: Aperture f/22; Shutter Speed 1/60

stevo01
26-10-2009, 4:21pm
Nice post shaggy, those two shots provide a good example of how depth of field (and specifically a narrow depth of field) can be used to draw attention to, or highlight, the subject of interest. In shot #1 the viewers eyes are drawn immediately to the lizard's eyes/head region, where as in shot #2 (with the greater depth of field) the photo is very "busy" and the viewer's eye isn't really drawn to one particular area of the photo, and the background and foreground/subject of the photo tend to merge into one.

ricktas
26-10-2009, 6:31pm
Good example of the difference that aperture settings can make to the result. At least now with an understanding of that, if you have a friend say they wanted a nice photo of themselves, you would know how to isolate them from the background and get a creative result. Which is the idea of this particular challenge.

seastorm
26-10-2009, 6:38pm
Good pics, shaggy!! :)

As Stevo says, the greater the DoF, the busier the pic seems to be, ie more distractions.

Can we have a new challenge now, Rick? :D

David
26-10-2009, 6:56pm
Had a question here but put it elsewhere because the genre Im thinking of is landcapes, not this type.

shaggydog
26-10-2009, 7:54pm
Thanks for the comments. I apologise for getting ahead of myself and will now crawl before I try and walk.

seastorm
26-10-2009, 10:16pm
Don't have to apologise, shaggy, sometimes it's a good way to learn :D

EdenJane
11-11-2009, 8:19am
Since my trusty D100 has spent most of its life on P mode I decided to start learning a little more about its features & working through the challenges is a great place to start. I am doing an online course at the moment that I paid for but I am learning a lot more here form looking at other people photos & critiques & reading all the beginner info ( thanks Rick)
So as my DOF I was a little limited as I had my two kids & my nephew to watch so was somewhat housebound so I lined up their morning tea.
Because it was indoors & the light wasn't great & I don't like the built in flash I upped the iso to 800... so unfortunately they are somewhat grainy but I think they illustrated the DOF thing ok. In the wide aperture F3.5 the front pear only is in focus & this seem to bring all the attention onto it & blur out other distracting elements. The narrow aperture was at F20 & in this aside from the grainyness ( due to poor light, high iso) all elements are essentially in focus...including things like the kitchen wall & bar stools. This makes the picture more about all visible elements & less about the pear! I used a 60mm nikkor lens. :)

42643
42644

bigdazzler
11-11-2009, 8:42am
thats a spot on example of DOF using Aperture selection .. Well done Edenjane :th3:

Ill just touch on something else (seeing as this is the Aperture/DOF thread ill be brief)

Take a look at your exif and note what happened to your shutter speed when you stopped down to f20 .. much much slower right ?? 1/160th down to 1/6th. I mention it because its a good indication of how two elements of the exposure triangle work in conjunction with each other. But thats a discussion for another thread .. just thought it was a good example.

Well done .. :)

EdenJane
11-11-2009, 6:26pm
Thank you :) getting my head around the interactions between all these things is going to be my next task. I just noticed I had my exposure compensation on -0.7 from a previous session..oops..that might explain what they are somewhat on the dark side! I plan to do the SSspeed challenge next.

Newbie79
03-12-2009, 9:58pm
Hi all, This is the first NTP challenge that I have done and my first attempt at posting.

I have taken four photos which I am posting. All photos were taken on Av mode of my camera and so all i changed was the f value between each set of photos.

Image one was taken at f22 and is of the Bonsai in the white pot in the fore ground. What I notice is that virtually everything in the photo is in focus and that because of this the bonsai is lost in all the other plants surrounding it. Image 2 is taken at f 5.6 and the first thing I notice is that the Bonsai seems to stand out from everything else (even from all the other plants) because it seems to be the only thing in focus. I also notice that the further back in the photo you look the more out of focus it seems to be (The other bonsai is less out of focus than the black bin in the background)

Image 3 is taken at f 22 and image 4 at f3.5 The comments i made above also seem to be true of these two photos with the exception that the difference between how much the background in each photo is out of focus seems to be much more subtle. If someone can please tell me if I am right or not but from the reading i have done this is because there is such a small distance between the front of the photo and the back (the fence)??? Is this right?

I know the photos are not master pieces but I am hoping they illustrate what I was meant to learn from the Challenge?

Thanks heaps

Matt

ricktas
04-12-2009, 7:11am
Good work Matt. Hope this taught you what the aperture does to your photo, and as you progress through the learning centre and the other challenges you will learn how to combine camera functions to achieve the desired result that you wanted.

What did you notice about the shutter speed as you changed the aperture?

kiwi
04-12-2009, 7:20am
I hope you dont mind, but can I add a couple of hard learnt lessons that I have found

Before deciding what apperture to choose, look at the background and think about what effect on that background changing your apperture will have....eg if a person is standing next to a wall it really will not matter to how the wall will look in the picture if you shoot at f/8 or f/1.8 but you'll get a much sharper picture at F/8

So, dont shoot wide open just because you can.

Newbie79
04-12-2009, 9:00am
Ricktas,

In answer to your question I noticed that the larger the aperture (smaller the f number) the quicker the shutter speed was. I am assuming this is because more light can get in at once the smaller the f number is.

I tried taking some more photos last night inside the house and noticed that the larger the aperture became the shutter needed to open for so long that it was impossible to hold the camera still long enough. I am assuming this again is a lighting issue?

A Question!

If I was taking a picture of object A and object B was behind this and then Object C was further behind again what would be the easiest way to work out how to keep both Object A and B in focus whilst having Object C out of focus. I guess i'm asking how can i quickly work out what my DOF will be before taking the photo so that I can keep the object I want in focus?

Thanks Matt

ricktas
04-12-2009, 9:26am
Re your question, the easiest way (other than experimentation) is to use a Depth of Field calculator. You put in the camera, lens details, the distance to subject, etc, and it tells you the distance front to back that will be in focus.

A good online example is here: http://www.dofmaster.com/dofjs.html

Newbie79
04-12-2009, 10:41am
Hi all,

Have been taking quite a few photos of different things practicing using Av mode and altering the DOF. Just thought I would share these with you all. Was amazed that i could control the DOF over such a small distance (from the front of my wedding ring to the back). One was taken at f 5.6 and the other at f22

Things are starting to make sense to me now. Thanks for your time.

Matt

seastorm
06-12-2009, 10:37am
Great pics there Matt, definitely can see the difference between the different f/ numbers :th3:

Amadeus
13-12-2009, 10:50am
Ok, just shot at the first thing I saw... nothing very creative here. :)

ISO left at 100, first shot is f/4 and second shot is f/22

f/4 brought the shutter speed to 1/100 (a lot faster) whereas f/22 brought the shutter speed to 1/6.

This caused the DOF to increase with f/22...

etherial
13-12-2009, 11:24am
You got it! :th3: Now along with the shutter speed challenge you did, you can see how you can use these aspects to your advantage to achieve a certain effect when shooting subjects.

Amadeus
13-12-2009, 12:02pm
Cheers. Was thinking I'd go back to the road scene from shutter speed challenge and shoot there again but with the change in aperture settings for comparison's sakes - is this worthwhile?

etherial
13-12-2009, 12:09pm
If you go back and look at the photos from the road you will see the aperture was changing itself to suit the shutter speed. In Aperture priority mode your camera will select the best shutter speed to get the correct exposure and if shutter priority mode the camera will select the right aperture to get the correct exposure. Which ever selection you choose they will give the same result.

Try it at home, put you camera on Av select F8 and point it at something. Note the shutter speed it picks. Then flick it over to shutter priority and select the shutter speed you just noted. Point it at the same subject (with the same lighting) and it should be close to F8.

When out shooting subjects the trick is to think what your priority is, are you trying for shallow depth of field or freezing action etc...which will determine which mode you use.

Amadeus
13-12-2009, 12:13pm
Sometimes I just gotta laugh at myself. Lol.

Ok, so deciding which way to go really depends on the subject at hand.

My biggest problem is remembering/knowing how to set this manually - without relying on the EV meter... but I suppose that will come with more practice.

etherial
13-12-2009, 12:21pm
Hey don't laugh at yourself, it does take a while you get your head around these concepts, if it was easy we wouldn't have guides and challenges like this one!

Don't feel pressured to use manual, it is perfectly ok to rely on the EV meter, especially while learning. Check out this (http://www.ausphotography.net.au/forum/showthread.php?t=13627&highlight=mode)poll about which mode people use, the majority use Aperture priority!

Amadeus
13-12-2009, 12:23pm
When out shooting subjects the trick is to think what your priority is, are you trying for shallow depth of field or freezing action etc...which will determine which mode you use.

Ok, got it, forgetting this motive caused me to ask that stupid question before ;-)

Gemini2261
18-12-2009, 6:59pm
#1: 1/400 sec
F/5.6
iso 100
#2: 1/15 sec
F/29
iso 100
The difference is obvious...

ricktas
18-12-2009, 7:05pm
So Gemini, now that the difference is obvious, could you go out and get better photos, understanding more about how your camera works?

Gemini2261
18-12-2009, 7:37pm
Wellll.....I don't know about that YET..HA

nudge2325
16-02-2010, 11:20pm
My Attempt at DoF. I think i have it sorted.
Sorry about the grainy pics but the camera decided on ISO 3200 ofr some reason. I checked the settings after checking the info on the file and the camera is set to ISO 400 so i dont know why it changed it.

1st was shot at F5.6 1/25sec 50mm
2nd was shot at F22 0.6s 50mm
http://i12.photobucket.com/albums/a238/nudge2325/IMGP0978.jpg
http://i12.photobucket.com/albums/a238/nudge2325/IMGP0977.jpg

Please let me know if this is right or if i have it all wrong...

mareech
06-10-2010, 5:31pm
Hi I have had a go at this challenge, but am having trouble getting a clear (non blurry) pic at f22. Is this because it was at low light (sunset)? Should I wait for better light? Also camera was handheld for shots, is f22 a setting where tripod is necessary? What type of situation is f22 used for a photo? I am tending to stay as low f as possible in my general practicing. Thanks, Maree

tanz
07-10-2010, 10:05am
Hi I have had a go at this challenge, but am having trouble getting a clear (non blurry) pic at f22. Is this because it was at low light (sunset)? Should I wait for better light? Also camera was handheld for shots, is f22 a setting where tripod is necessary? What type of situation is f22 used for a photo? I am tending to stay as low f as possible in my general practicing. Thanks, Maree

Hi Maree, I would say that your pics were blurry because f22 is a small aperture opening and the camera would compensate by choosing a slow shutter speed and then it was probably too slow to hand hold. So you could either try taking the shot at better light, but then you won't get the sunset, or using a tripod or sitting your camera on something solid. You could also try adjusting your ISO. I haven't done a lot of landscapes or seascapes but my understanding is you would use around f22 for photo's where you want everything in focus and not a shallow depth of field. I am still a newbie myself so I hope this makes sense and I hope it helps.

mareech
07-10-2010, 10:37pm
Hi Tania, thanks for your reply, I wasn't sure if changing iso would change the effect of the exercise. I guess I should have experimented then I would know. I did take some with camera sitting on a rail and they were much better. Thanks again, Maree

la lumiere
07-10-2010, 10:45pm
Ok, so here is one of my efforts - I tried a couple of subjects. Various results. Started off taking a snail but by the time I sorted settings it had done a runner!

The f numbers still confuse me- I think this correct.... smaller number bigger hole- so smaller the number, more available light (less need for speed?- slower speed OK) .
Bigger the number smaller the hole, speed should be slower to have time to let in enough light. When the speed gets slower it is harder to get crisp image. (I guess you would have to use a tripod.) Advantage to smaller f number - isolates the subject from the background
Disadvantage- if the object is bigger only some of it may be in focus if it's not flat/parallel to the camera , if very bright day may be overexposed (?)
Advantage to higher f number - more of the picture in focus
Not sure, but could be advantage to use for moving objects - less room for error- can shoot at higher speed for freezing action (tho' I presume on full manual setting you can have big hole and fast speed---hmmm I'll think about that!)
Disadvantage - all the junk lying around in the background is obvious!

Photo 1 .... f22
1/160
ISO 100
Photo 2..... f5.6
1/200
ISO 100
One question (of many) the exif (?) data said.... exposure bias -1......I did notice this in view finder.....did I do that or is it automatically set?

http://i1093.photobucket.com/albums/i432/Housiet/Aus%20photog/IMG_2773.jpg

la lumiere
07-10-2010, 10:49pm
Her 'tis.. I can't quite work out how to put both photos on at once. :o
http://i1093.photobucket.com/albums/i432/Housiet/Aus%20photog/IMG_2772.jpg

Katt
12-10-2010, 3:49pm
Hi All,
Here are my first attempts at trying depth of field.

http://farm5.static.flickr.com/4153/5073823033_b5746b9038_z.jpg (http://www.flickr.com/photos/47864876@N06/5073823033/)010 (http://www.flickr.com/photos/47864876@N06/5073823033/) by Katt1970 (http://www.flickr.com/people/47864876@N06/), on Flickr


http://farm5.static.flickr.com/4105/5073760499_d9ef44259f_z.jpg (http://www.flickr.com/photos/47864876@N06/5073760499/)022A (http://www.flickr.com/photos/47864876@N06/5073760499/) by Katt1970 (http://www.flickr.com/people/47864876@N06/), on Flickr

Regards - Katt

ricktas
12-10-2010, 5:13pm
la lumiere, you are correct, the smaller the F number the bigger the aperture will be. Apertures are a fraction, so consider it this way 1/4th of something is bigger that 1/16th of the same thing. Thus f 1/4th is bigger than f 1/16th, but rather than write them as a fraction we just write f4 or f16.

Exposure bias is a different setting again. It only works in auto or the semi-auto modes on your camera. If you adjust the bias, your camera will under-expose, or over-expose the scene, based on what it's meters read.

ricktas
12-10-2010, 5:14pm
Katt, you have posted two very nice photos, but what have you learnt about how a different aperture affects the way your photos come out?

Katt
12-10-2010, 5:21pm
Hi Rick,
The best thing I have learnt is that by using a wide aperture provides some really interesting shots. In the past I have always used a narrow aperture where everything is in focus & quite often, this has resulted in a really boring photo without much focus on the subject. I am really pleased I have learnt about this & think it will be really useful when travelling & taking portrait shots.
Thanks for your comment
Katt

ricstew
17-10-2010, 3:19pm
here is my effort.......I am trying to work out getting BOTH eyes in focus........using aperture and DOF.
1 1/6 at f7.1 both eyes reasonably in focus.......
http://i1012.photobucket.com/albums/af243/ricstewa/IMGP6856-Edit.jpg?t=1287288336

2 1/20 at f5.6 front eye more in focus due to angle of head. In order to get both I would have had to go to f7 or 8 and increase the dof?
http://i1012.photobucket.com/albums/af243/ricstewa/IMGP6853-Edit.jpg

3 1/20 f5.6 and here the angle is less so the dof looks shallower
http://i1012.photobucket.com/albums/af243/ricstewa/IMGP6856-Edit.jpg?t=1287288606

clonaz2
23-10-2010, 12:12pm
Check out this (http://www.ausphotography.net.au/forum/showthread.php?t=13627&highlight=mode)poll about which mode people use, the majority use Aperture priority!

I move with the herd. I hardly use anything but aperture priority now. Thanks for an enlightening thread.

Bryan

Cheach
26-10-2010, 11:53pm
Apertures are a fraction, so consider it this way 1/4th of something is bigger that 1/16th of the same thing. Thus f 1/4th is bigger than f 1/16th, but rather than write them as a fraction we just write f4 or f16.

Thanks Rick. A piece of puzzle just falls into place.

aurora
05-01-2011, 7:15pm
I think I'm getting it !!!

Flower at A20

http://i859.photobucket.com/albums/ab159/aurorapb/DOF_pink_test/20_pinkp.jpg
Flowers at A5.6

http://i859.photobucket.com/albums/ab159/aurorapb/DOF_pink_test/56_pinkp.jpg
Flowers at A8

http://i859.photobucket.com/albums/ab159/aurorapb/DOF_pink_test/8_pink.jpg

aurora
05-01-2011, 8:45pm
What I've learnt...well
I think the smaller the f number eg 5.6 the more light but can also become too bright and the colour can also be a bit washed out, whereas the larger f number eg f20 there is less light and the pix can be more true to the colour. Of course bigger number sharper the pix. Have I got it right? still doubting myself. If I've got it than I am not sure what to do with the washed out colour especially if you want a blur background.

aurora
06-01-2011, 1:01pm
I just found out another thing about F stops. I was taking more shots on various f stops and discovered the sharper you get ie f20 the more shadows come into the picture, at f8 or f5.6 the shadows aren't as obvious. This must have something to do with the light but not sure what !!!

MBsa
11-01-2011, 1:53pm
as part of my course i did, depth of field was one of the topics we covered. Here is one of my shots which I also used in my assessment. I had fun learning and playing around with it.
http://farm6.static.flickr.com/5244/5344407525_a78d9803d8_b.jpg (http://www.flickr.com/photos/melbphotography/5344407525/)
depth of field (http://www.flickr.com/photos/melbphotography/5344407525/) by melbphotography2011 (http://www.flickr.com/people/melbphotography/), on Flickr

ricktas
11-01-2011, 2:12pm
as part of my course i did, depth of field was one of the topics we covered. Here is one of my shots which I also used in my assessment. I had fun learning and playing around with it.

So what did you learn? This challenge was about presenting photos and telling us what you learnt. not just posting them saying you had fun learning. The idea of challenge threads is that members present their photos and then talk about what they learnt about the challenge, to help others learn as well.

MBsa
11-01-2011, 2:27pm
Sorry Rick, forgot to put that bit in. I learnt that smaller f number is smaller / shallower depth of field and larger f number is larger / wider depth of field. Shallow depth of field gives the blurred background, wider depth of field has everything in focus. Shallow is good for portraits where the background is busy, as it will blur it out. Wider is better for family portraits so that everyone is clear. :)

MBsa
11-01-2011, 2:28pm
Also shallow depth of field has a quicker shutter speed and wider depth of field is slower and may require a tripod or flat surface

macrocephalic
01-03-2011, 12:07pm
Rick, can we have these NTP challenges as stickies, or in their own subfolder with a link from the NTP book? I think it would be good if you could, for example, read through the section on aperture in the NTP book then link to this thread where you could try out what you just read and post the results.

ricktas
01-03-2011, 12:14pm
Rick, can we have these NTP challenges as stickies, or in their own subfolder with a link from the NTP book? I think it would be good if you could, for example, read through the section on aperture in the NTP book then link to this thread where you could try out what you just read and post the results.

No, cause we create new ones each year, and another will be created soon with a different challenge

ladysith
23-03-2011, 2:54pm
I can't access the link =(

juanny
08-04-2011, 11:18am
Hi

Well this is my first attempt at a challenge. I have read through the NTP section on Aperture and after a few attempts i have these photos of a bird of paradise in my garden using the av mode. I have had a lot of trouble using the av mode in that I don't seem to always get the results that I am hoping (using F5.6 but background still in focus) but after reading all the info on this site I think i am getting the hang of it.

For the first photo i used an aperture of F5.4 (I was sure i had used 4.5) and the second photo F38. The differences I noticed between the two was that photo one the background was out of focus which made the flower stand out more and become more of a feature. I noticed too that the colours were brighter on the flower than in photo 2. Photo 2 the flower doesn't stand out as much as the background is in focus. Any advice on how I can improve is welcome. Thanks for looking :)

ricktas
08-04-2011, 1:22pm
Good work Juanny. As you have found, changing the f-stop, changes what is in focus in your photos. You can use this knowledge to make your subjects stand out from the background, when you take photos in future. The other side of this is, that if you are taking a landscape for example, you should also know what f-stops are good for ensuring everything in your photo is in focus, from the rock in the foreground, to the distant hills. Keep practicing, and reading the NTP.