Learning how to expose properly: the basics

mmacleodbrown

Regular
Oct 10, 2010
London
Bill - thanks for the example - nice photo..

wt21 - Thank you - I didn't understand the relationship between shutter speed and ISO, I thought that ISO was a way of measuring how much light sensitivity the sensor picked up, or how sensitive it was at any given moment. I had no idea that changing the ISO changed the shutter speed, I can remember as a kid having a 110 camera with film rated at 400 ISO, I didn't know that if I changed the film speed the shutter speed changed as well.I presumed that like film, the sensitivty of the sensor changed when using different ISO speeds.
I think I need to go take some photo's at the weekend with different ISO values and look at the exif data to see what shutter speeds were used, then hopefully I can get my head around it..
Im getting there, after this weekend, I have the beginings of an understanding about shutter speed/apperture and the effect it can have on a photo - I want to emphasise that is just a beginning though :)
Now I need to get my head around the third corner of the triangle...

As for getting a DSLR or micro 4/3 - I can see me getting something in the future, but I think Im better off learning the basics with my S95 first and understanding the limits of the camera, so I have a better idea of what I want in a DSLR.
The other thing that puts me off is the size, the whole point of a S95 is having a camera all the time, spending a couple of grand on a DSLR and some lenses is hard to do when Im worried that it won't come out to play enough..
I had a powershot G2 which was only used (on auto!) 30-40 times a year and I don't want to repeat that with more expensive kit - not yet anyway..

Mind you - there is an Olympus Pen E-P1 going cheap on the members forum :eek::biggrin::biggrin:
 
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BillN

Hall of Famer
Aug 25, 2010
S W France
Bill
If you want to experiment with a (DX) DSLR - you could probably buy a cheap, but very good, DSLR, something like a Pentax K100D with say a AF "kit lens" off ebay for not much more than £100/£150.

The pentax is small, with very user friendly control and MF old pentax glass, (which is backwards compatible to the very early lens), is very cheap and very good - a 50mm f1.8 or similar would be about £30
 
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christilou

Legend
Jul 13, 2010
Sunny Frimley
I'll second that Bill. I bought a little Nikon D40 and kit lens and it taught me an awful lot. I wasn't afraid to change the settings and experiment with it. I've also been able to learn from countless members here and "there" and am still benefiting from all the vast amount of knowledge other people are willing to impart :biggrin:
 
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BillN

Hall of Famer
Aug 25, 2010
S W France
Bill
Thanks for this Bill - I will bear it in mind, are the lenses usable on later models as well?
All pentax lens, are compatible with current Pentax DSLRs - the early screw M fitting and the K bayonet - Pentax were/are one of the best lens makers
The MF lens are a bargain, (compared with others) and are freely available
There may be 1 or 2 exceptions, but these would be very specialised lens

If you have/get an M43 - they will also fit that format, (with adaptors)

You can/will have a lot of fun with a DSLR

Their DSLRs are also smaller than Canon or Nikon and compare in size with Olympus

(PS - the K100D uses 4 AA (rechargeable) batteries - good for some people not for others - depends on your viewpoint)
 

wt21

Hall of Famer
Aug 15, 2010
Bill is right -- a cheap DSLR is a great way to learn. I would even recommend a cheap prime lens. I used Canon, so for me it was a 400D and a 35mm f2.0 lens, but I'm sure the Pentax would work just as well.

You ARE right about ISO (at least practically, though not technically). You can think of ISO as "sensitivity to light"

ISO, shutter speed and aperture work together to determine "exposure." There are generally set exposure values. See here (especially "tabulated exposure values" Exposure value - Wikipedia, the free encyclopedia Moving up or down one exposure value is moving on "full stop" in exposure.

There's much to explain here, but much that is already explained elsewhere. I don't have time this am to type, but try reading explanations at the following sites:

Exposure: Glossary: Learn: Digital Photography Review
The Luminous Landscape Tutorials contents
Digital Photography Tutorials (this was one of my favorites)
And the ever infamous wikipedia.

Also, Bryan Peterson's Understanding Exposure should be a good primer on exposure.

One thing I do recommend learning is the full stops on the aperture. Generally, progressing by full stops, it goes: 1.0, 1.4, 2.0, 2.8, 4.0, 5.6, 8.0, 11, 16, 22, 32. There's a mathematical reason for that odd progression, but I just memorized it by writing it on a card.

So, if I am shooting at ISO100 shutter speed 1/200 and f/8.0 and I want to lower aperture to f/2.8 (for less depth of field, but it also lets in more light), that's four whole stops (8 to 5.6 to 4.0 to 2.8). I would need to either boost shutter speed 4 stops (200 to 400 to 800 to 1600) or lower my ISO (100 to 50 to 25 to 12.5 -- well, can't do that on modern digital cameras) to maintain the exposure. Alternatively, I could attach an ND filter, or come back some later time when the light is less.

Good luck with your learning! Concentrate on exposure (and also the depth of field work you've been doing). If you master these, you'll get a lot of the technical side of photography down (now, as for the art side... well, I'm still struggling with that!)
 
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BBW

Legend
Jul 7, 2010
betwixt and between
BB
Excellent explanations and links wt21! Lots of good info in this thread as well as good suggestions regarding how to learn with different types of cameras.:2thumbs:

Martin, I encourage you to both check those links that w21 has suggested. Perhaps your library has some good books, they don't need to be new books in order for them to be good.
 

mmacleodbrown

Regular
Oct 10, 2010
London
Big thanks to wt21 and Bill for your kind advice..
Im studying for my exams at the moment, so time is tight, but I will work through those links provided..
I bought 'Understanding Exposure' last week with my camera and have started reading it, though it does seem more biased towards DSLR owners as alot of the settings he talks about are way beyond the range of my S95. It is still a good book though, and the basics apply no matter what camera is used.
I hadn't thought of buying a cheap DSLR to learn on, I will go and investigate this further as this does seem a really good idea, especially if I go down the 'old model' route and pick up something cheap - thanks for that, I will keep an eye out and let you all know what I get..

What have you all started :wink:
 

wt21

Hall of Famer
Aug 15, 2010
It's quite simple -- we are actively pulling you into our own delirium!!!

What we've talked about so far, both with Peterson's book and all the other posts -- is mainly about exposure, with a bit on DOF. Important stuff! But, it's not that Understanding Exposure is biased towards a DSLR, it's that a DSLR is more flexible than a point and shoot.

But, there's lots of great work being down on small sensored compacts, too. You just have to learn the limits. One thing a small compact does that a DSLR CANNOT do is take photos in lower light with greater DOF! Also, compacts can sometimes take better macro shots because they have a naturally deeper DOF (sometimes the narrow DOF on a DSLR makes taking macros harder).

Peterson has another book titled "learning to see creatively" here in the US Amazon: Amazon.com: Learning to See Creatively: Design, Color & Composition in Photography (Updated Edition) (9780817441814): Bryan Peterson: Books: Reviews, Prices & more

And another: The Photographer's Eye by Freeman (and Freeman has other books, too). Much of what these two books talk about is color, composition, perspective and framing. These approaches can help with any camera, as it's about what you are shooting, not what you are shooting with.

In a simplistic approach, Exposure is sort of the "technical" end of shooting, and composition, color, perspective and framing is more the creative end. Although, exposure is important to the creative side, as well, especially with things like high-key or low-key type photos. See High-key lighting - Wikipedia, the free encyclopedia as an example, or http://en.wikipedia.org/wiki/Low-key_lighting. (In short, light meters in your camera want to average out the exposure to middle-grey. Well, that's fine for boring photos, but you will want to learn how to control exposire to get what you want, not "average" gray!)

Welcome to the collective insanity known as photography ;)
 

mmacleodbrown

Regular
Oct 10, 2010
London
Currently trying to browse ebay whilst at work!
I have created a seperate bookmarks folder and all the links you have kindly sent me are going into it so that I don't miss anything and I will read when studies permit - I have an exam on dec 10 and another in March :-(
At least the camera reading doesn't feel like studying - at least not in the same way..
 

BillN

Hall of Famer
Aug 25, 2010
S W France
Bill
One thing a small compact does that a DSLR CANNOT do is take photos in lower light with greater DOF! Also, compacts can sometimes take better macro shots because they have a naturally deeper DOF (sometimes the narrow DOF on a DSLR makes taking macros harder).

??? - can you explain what you mean by this - I would think that the reverse is true

DSLRs can take shots at far higher ISOs than compacts

DSLR longer macro lenses
 
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wt21

Hall of Famer
Aug 15, 2010
True. I was thinking at the same ISO. It might depend camera-to-camera. I think the point of the new S90/S95 sensor is that it's better in low light than other compacts, but I don't own one so I couldn't say. So, an S95 800ISO might be better than an old Canon XTi 1600 ISO, but compared to a more contemporary DSLR that performs better in low-light (say, a D90), I'm sure the edge to the DSLR would be even greater.
 

BillN

Hall of Famer
Aug 25, 2010
S W France
Bill
Thanks - wt21

It's that I'm used to Nikon and have a D300 that is great in low light - in fact it's great all the time - (OK folks it's big)
(I keep thinking of upgrading to a D700 as it is FF and it gets back to true 35mm so that I can really appreciate a few of the old Nikkor (wider) lens, (lenses -not sure which), that I have)

by the way the EP-1 is really good at acceptable ISOs, hand held in low light with no flash, especially with the Panasonic M43 20mm f1.7 - you benefit from the Oly IS plus the "wide" f1.7
 
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mmacleodbrown

Regular
Oct 10, 2010
London
If you want to experiment with a (DX) DSLR - you could probably buy a cheap, but very good, DSLR, something like a Pentax K100D with say a AF "kit lens" off ebay for not much more than £100/£150.

The pentax is small, with very user friendly control and MF old pentax glass, (which is backwards compatible to the very early lens), is very cheap and very good - a 50mm f1.8 or similar would be about £30
Im seeing an olympus e420 for £140 with kit lens - is that worth it, or should I stick with the 100D which is hopefully around the 120 mark (subject to bidding)
Are olympus lens expensive?
 

BillN

Hall of Famer
Aug 25, 2010
S W France
Bill
I'm not an Olympus DSLR user, so I cannot comment - maybe someone on here is - but I am sure that the Olympus will be good - I would think that Olympus MF lens will be a touch more expensive than Pentax, as there are fewer around -
(if you are after AF lens there are quite a few third party manufacturers, (i.e. Sigma and Tamron), who make really good glass to fit - just make sure that you get the lens with the appropriate mount - i.e. a Tamron lens with a Pentax mount - you may see such advertised with the used cameras, as they are popular and cheaper that the cam manufacturers lenses
also, as has been indicated, 50mm f1.8 AF lens are quite cheap second-hand

no need to rush, there are plenty around - do a little research, (dpreview - look at a few of the old reviews), - but the reason I picked out Pentax, (rather than say, Canon), is that the modern Pentax DSLRs can use the lenses from the older Film SLRs - this is not quite as simple with Nikon, (you need to get one of there better speced DSLRs to be able to use ALL the MF Nikkor lenses - and it is certainly not the case with Canon as most of their MF stuff is not compatible with their DSLRs as they changed the mount and register distance).
If you are only going for AF lens there are lots of DSLR around, (other makes), with a kit zoom - say 18mm to 55mm or 70mm and a kit telephoto, say 100mm to 300mm - but if you want to explore DOF you need a lens with with an aperture starting as low, (fast), as possible - but as you are on a budget the best bet is a 50mm f1.8 AF lens - and remember that Macro AF lenses are expensive - (should not say this but all a Macro does is have the ability to focus at closer distances - life size - but I'll be shot down), - so if you are into macro on a budget, (say under £75 for the lens - then an MF Macro is the only way to go unless you want to start messing with extension tubes and the like)

Also don't get hung up on pixels - 6 mega is fine if you are buying at the right price - i.e. the £100 to £150 mark with a lens or two

But as I indicated I only know Pentax and Nikon SLRs/DSLRs

Also look at the batteries - as I said the Pentax uses 4 x AA - whereas the Oly may use specific batteries - could be a cost consideration

I'm rambling - so I'll stop
 
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wt21

Hall of Famer
Aug 15, 2010
I would recommend the pentad Bill is talking about over an oly dslr. The oly dslrs use a 43 sensor. Same one as in an ep1 - which I own myself, but it really takes a track to get dramatic dof.

If you really want to play with dof, get a nikon or canon or a pentax. I know canikon better, and both makers have good, inexpensive lenses to start. For instance, either canon or nikon, and I'm sure pentax too, have a cheap dslr body with the availability of cheap 50mm 1.8 prime lenses. In the US, the canon version is $95. That's a great way to learn with a lens like that, because you'll see a DRAMATIC difference on dof. Much more than an oly dslr with kit lens.
 

mmacleodbrown

Regular
Oct 10, 2010
London
If you want to experiment with a (DX) DSLR - you could probably buy a cheap, but very good, DSLR, something like a Pentax K100D with say a AF "kit lens" off ebay for not much more than £100/£150.

The pentax is small, with very user friendly control and MF old pentax glass, (which is backwards compatible to the very early lens), is very cheap and very good - a 50mm f1.8 or similar would be about £30
Oh Bill - what have you done?
After scouring the web, I have managed to pick up a Pentax K200D body for £115 delivered, so Im feeling rather happy with that (Im lying, Im estatic!)

As it is body only, I need to get a couple of lenses, I know I want a macro lens, Im off to search now, and a good general purpose lens to play with DoF etc, going to try and find the kit lens that comes with this..
Happy to receive any good recommendations

I've seen these for macro?
http://cgi.ebay.co.uk/Macro-Close-Up-Lenses-Set-Pentax-K100D-K110D-K10D-/190461776314?pt=UK_CamerasPhoto_CameraAccessories_CameraLensesFilters_JN&hash=item2c586811ba
 

BillN

Hall of Famer
Aug 25, 2010
S W France
Bill
I think that there is a good, small book, The Magic Lantern Guide for the K200 - probably £10 off Amazon

Then you have to decide if you want an Auto Focus, (AF) Lens - (the modern ones), which came with the camera - should be lots of the basic kit lens around - cheap - OR
A more expensive Pentax Auto Focus fixed lens - say 50mm or wider

Or are you looking to get a few Manual Focus Pentax K bayonet fitting lens - again cheapish - but get the A not the M as it will meter a lot better on the K200 - for starters try the 50mm F1.7 A

I think that I have a photo of one which I will post as soon as I find it

Read up on Pentax lenses - the MF one come in the older screw fitting and the later K bayonet fitting - the K bayonet and as I said the "A" lens

Asahi Pentax, Takumar and Super Takumar are all part of Pentax - I have quite a few older pentax cams plus a few lens - The Pentax history is also very very interesting - read up on it

The Pentax 50mm f1.7 A is a really good piece of glass

Good luck


Bill
 

BillN

Hall of Famer
Aug 25, 2010
S W France
Bill
Tamron produce some good budget (cheap) AF lens for the Pentax

If you like telephotos - the Tamron AF70 300mm f4-f5.6LD Macro can be picked up for maybe £70 on EBay - OK it's plastic etc., and it is not a pro lens by a long way but you will get some great shots with it in good light and with the (DX) sensor it will give you "reach" up to over 450mm

I think that the Pentax kit lens is the SMC Pentax - DA 18 55mm f3.5-5.6 AL - again, maybe £30 off Ebay

The DSLR and the compact camera are "world's apart"



Taken with the Tamron at 300mm (450mm) @ISO 800 jpeg - shows the OOF you can get even with a cheap telephoto, (f5.6)

 

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