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Ken-f
29th January 2009, 10:53 PM
I'm fairly new to photography and have a 450d with a 18-55 and 55-250 IS lenses.

Now i'm finding it annoying that i have to keep changing the lenses because i want just that little bit more distance from the 18-55. But when i use the 55-250 i'm usually too close to the subject.

What i want to ask, is if i get a lens that is 17-85? or is it 18-85. Will that make my 18-55 lens useless to me?? Another question is....what is this USM think i keep seeing on the lenses? ahaha, all i know is it makes it more expensive!! Ultrasonic something?

Hmmm okay, i keep thinking of more questions.

When taking photos, is there a general rule?? For example, always try to have biggest aperture and faster shutter speeds. Or smallest ISO? Or is it different for every photo?

Oh yea, last one. I'm about to buy a 50mm f/1.8 lens. Anyone know the cheapest place to get one near Brisbane? Cheapest I've seen is an online price of $124 from the GC.

Thanks :)

krasivy
29th January 2009, 11:15 PM
The EF-S 17-85mm is a great lens to go with the 450D and I personally recommend it. It's an everyday and almost-everything lens that you can be confident in having it with you all the time.

USM = Ultrasonic Motor : this is a quieter AF motor, as compared to the ones found in the more-general of Canon lenses.

As for the 18-55 versus 17-85:
- in terms of focal length, yes - the latter does render the former rather useless; however
- the 18-55mm lens has a lower f-stop value of f/3.5 at 18mm, as opposed to the 17-85mm's f/4.5 at 17mm (this probably matters more when you take pictures in non-so-bright places).

One of the reasons why I've given up on the 17-85mm is because of the higher f-stop value at the shortest focal length, since I tend to do a lot more shots in the dark than during broad daylight.

Ken-f
29th January 2009, 11:20 PM
Yea. A lot of photos i find are in darker areas. The aperture seems too small? I hope i'm using the right terminology. Thats kinda why im buying the 50mm just to muck around with. Its so cheap relative to the other lenses out there.

krasivy
29th January 2009, 11:23 PM
Hmmm okay, i keep thinking of more questions.

When taking photos, is there a general rule?? For example, always try to have biggest aperture and faster shutter speeds. Or smallest ISO? Or is it different for every photo?

Oh yea, last one. I'm about to buy a 50mm f/1.8 lens. Anyone know the cheapest place to get one near Brisbane? Cheapest I've seen is an online price of $124 from the GC.

Thanks :)

Well, there's really no general rule... but you have all the settings at your disposal to play with. When it comes to photography, it's all about experimentation - and because it's all digital, you can take shots at your own leisure without having to worry about wasting film :p

But these are some of my general rules:

- For a 450D, I would not go beyond having a setting of ISO400. You could try ISO800, but you may start to find unwanted artifacts (aka "picture noise") in your shots. A higher ISO setting allows for faster shutter speeds at higher f-stop values, and useful to play with when taking shots in the dark without a flash, for example.

- Re the f-stop setting : the lower the value, the faster shutter speed that you can achieve. However, the lower the f-stop value, you will find that objects that are out-of-focus becomes more blurred-out - and this is usually referred to as "bokeh". Plus, an image taken at a lower f-stop value won't be as sharp. For example, a picture taken at f/2.8 will be somewhat sharper than that of one taken at f/1.8.

Try playing around with the different modes. I usually have my camera in the "A" position (Aperture priority), and let the camera decide for me the appropriate shutter speed setting. An f-stop value of f/2.8 and ISO400 is good for most shots in my opinion - but of course, I encourage you to play around with the different settings and experiment with the different effects that these can offer.

Finally, a price of $124 for the 50mm f/1.8mm mark II lens is not bad. Just make sure the one they are selling is "mark II", and not a "mark I".

Have great fun with the 450D - it's a great camera! :cool:

Ken-f
29th January 2009, 11:41 PM
Yea. I'm usually always playing in the M setting. It's good fun. I guess for the shots i need to take in a hurry i could just use P.

As for ISO settings, at 1600 there is a lot of noise, but it helps so much more in the darker areas im shooting. Why don't you suggest shooting below ISO400? What kind of qualities do you see with lower ISOs? I notice the picture is a bit darker.....but if i wanted this, i would probably have first sped up the shutter speed.

So are you saying the bigger the opening/aperture, the less sharp my photo will be? Oh yea, and i love bokeh :P ahah

krasivy
29th January 2009, 11:52 PM
Yea. I'm usually always playing in the M setting. It's good fun. I guess for the shots i need to take in a hurry i could just use P.

For some reason, I never go for the P setting - may be I just don't know how to use it :p

It's either full-auto, A or full manual (M) for me. I do a lot of product shots, so control is key at times.

And lately, I've become lazy and have been relying on a Panasonic LX-3 to do the same job... ;)


As for ISO settings, at 1600 there is a lot of noise, but it helps so much more in the darker areas im shooting. Why don't you suggest shooting below ISO400? What kind of qualities do you see with lower ISOs? I notice the picture is a bit darker.....but if i wanted this, i would probably have first sped up the shutter speed.

I wouldn't use anything beyond ISO800 on a 450D - the pictures are unbearable to the eyes, so to speak.

Actually, I suggested ISO400 as a ceiling - of course, you can use anything below for an even-better-looking shot. I stick with either ISO200 or ISO400 for my shots, since I do a lot of indoor / darker shots (hence, lesser the opportunity to go for anything lower).


So are you saying the bigger the opening/aperture, the less sharp my photo will be? Oh yea, and i love bokeh :P ahah

Yes, that is exactly right :)

Try experimenting with a daytime shot at different f-stop values, and you will see what I mean then.

For truly amazing bokeh, go below f/1.8 ;)

Ken-f
29th January 2009, 11:57 PM
ahah, thanks for all your advice. Very helpful.

My bad, i meant Auto mode, not P. I don't really understand it either. ahha. All i know is the flash on that setting is not automatic. hehe.

I'm buying the 50mm so i can use it at f/1.8. Tested it out at work and loved it. (i work in an electronics store)

krasivy
30th January 2009, 12:18 AM
You should get some great fun out of the 50mm... me and my friend shares use of a 50mm f/1.4, which is a great lens and well worth the money (whenever you're ready).

It probably wouldn't matter to you now. But if you decide to move up to better cameras later, like the 5D and beyond, EF-S lenses will not work on these because of the different mount design. The "EF" lenses will work on all Canon cameras, but EF-S only on the 450D / 40D / 50D (current) models.

The 17-85mm is an EF-S lens, so thought I'd point that out to you :)

dotnet
30th January 2009, 02:42 AM
Yes, the 50mm is going to be an eye opener compared to the kit zoom lenses.

As for auto vs A vs P, "Programmed", "Aperture priority" and "Shutter priority" are all auto exposure modes. The camera decides what exposure is required. In A you get to choose the aperture, the camera will supply the appropriate shutter speed. In S you dial in the shutter speed, the camera selects the aperture. In P the camera suggests a setting for both, you can use the wheel to run through larger aperture/smaller shutter speed values and vice versa.

In Manual the camera will still meter and suggest the proper exposure, but you can set both aperture and shutter speed, overriding the camera's opinion. This is particular fun with digital SLRs, where image frames don't cost anything. You can experiment to your heart's content. A very useful aid in this game is the histogram display. Once you've become good at guesstimating exposure you just shoot away and check the histogram for whether you are in the right ballpark. If not, correct A or S and shoot again.

histogram |ˈhɪstəgram|
noun
One of the most under-appreciated features in digital SLRs

Chers
Steffen

Ken-f
30th January 2009, 10:24 AM
OH yea!! ANOTHER question. That histogram! how on earth do I use it? I heard you have to be within some limit??

scottgrot
30th January 2009, 12:31 PM
With regards to aperture, shutter, and ISO; There are 3 ways to control light -- with their varying consequences.

1) Aperture. An open aperture (f/2.2) lets more light through than a closed aperture (f/11).
f/2.2 has a shallow depth of field (area in focus); f/11 has large depth of field.

2) Shutter. A slower shutter (1/8 of a second) speed lets in more light than a fast shutter (1/500 of a second).
If you have a shaky hand, then you might want to go for a faster shutter speed, or brace your elbows to try and prevent the camera from shaking.

3) ISO. This relates to film speed. If you think of ISO/ASA 100 as a film with a relatively thick coating of light sensitive "stuff" on it. Because there is so much "stuff", you will get more detail in your image. However, because there is so much "stuff", you need more light for it.

The higher the ISO, the thinner the coating of "stuff". Because the coating is thinner, it needs less light. And because there is less "stuff", there is less detail. In this respect, less detail gives you more grain in the image.

Digital sensors don't have grain in the same way as film. Digital sensors have what is termed noise. This is what you see all over the image when you set the ISO to 800 or higher. This is why it is being suggested that for your particular model camera, to keep the ISO below 400.


In regards to the histogram, on the horizontal axis on the left you have black going through to white on the right.
The vertical axis is the amount of what is on the horizontal axis.
So if your image is bright and/or over exposed, the graph will be over towards the right.
If your image is dark or under exposed, the graph will be over to the left.

It's totally up to your discretion, but it might be good to keep the histogram between the upper and lower ends. That is, avoid having the graph look like a skateboard jump ramp, and more like an ant hill.

dotnet
30th January 2009, 02:38 PM
There are several good description of how to use histograms on the net, including this (http://www.luminous-landscape.com/tutorials/understanding-series/understanding-histograms.shtml) one. That site is an awesome resource for photographic know-how and techniques, BTW.

Cheers
Steffen.

Ken-f
30th January 2009, 02:43 PM
Thanks guys. I'll read up more on it. Can't wait to get another lens. Hopefully Sunday.

Cods
30th January 2009, 03:13 PM
You should get some great fun out of the 50mm... me and my friend shares use of a 50mm f/1.4, which is a great lens and well worth the money (whenever you're ready).

Ken, I'm a relatively recent starter in the wonderful world of DSLRs, and to me it looks like the other guys have pretty much covered everything that it took me days to work out myself when starting.

Probably the only thing I might add would be a note regarding "full frame (http://en.wikipedia.org/wiki/Full-frame_digital_SLR)" DSLR sensors versus "less-than-full-frame" (sometimes referred to as APS-C (http://en.wikipedia.org/wiki/APS-C) or FOVCF (http://www.the-digital-picture.com/Canon-Lenses/Field-of-View-Crop-Factor.aspx)) DSLR sensors. You probably are already aware of this, and my apologies if so, but I add it to the thread just in case. For example, the Canon 5D MkII is a full frame DSLR, whilst your 450D and my 40D are APS-C, as krasivy alludes to in his post.

Getting to the point, the "XXmm" or "XX-YYmm" that lenses are marked with only applies perfectly when attached to a full frame camera. If the same lens is attached to an APS-C equipped DSLR, then (and excuse me for simplifying) basically the lens acts as if it has been zoomed by a factor of 1.6 (http://www.luminous-landscape.com/essays/Equivalent-Lenses.shtml).

So a "50mm" lens on a Canon 450D will effectively be an 80mm lens.
The same 50mm lens on a Canon 5D MkII is effectively a... 50mm lens.

A picture is worth a thousand words - this one's from .the-digital-picture.com's explanation of the effect (http://www.the-digital-picture.com/Canon-Lenses/Field-of-View-Crop-Factor.aspx):http://www.the-digital-picture.com/Images/Other/Field-of-View-Crop-Factor.gif

An aside: When I was buying our camera and lenses, I was advised that a 50mm 'normal lens (http://en.wikipedia.org/wiki/Normal_lens)' is a nice lens to muck around with and learn the craft (http://vothphoto.com/spotlight/articles/forgotten_lens/forgotten-lens.htm) and have fun. I also knew that we had been disappointed with blurred shots of our kids taken in low light with our Canon G3, so I combining the two requirements and taking our budget into account we settled upon a Sigma 30mm f/1.4 DC HSM (http://www.the-digital-picture.com/reviews/Sigma-30mm-f-1.4-EX-DC-HSM-Lens-Review.aspx). 30mm x 1.6 = 48mm, close enough to 50mm for us. It's been really nice.

Cods
30th January 2009, 04:15 PM
And lately, I've become lazy and have been relying on a Panasonic LX-3 to do the same job... ;)
Hey krasivy, I'd be really interested in your impressions of the LX-3. Thinking of replacing our broken Canon point and shoot with it.

krasivy
30th January 2009, 05:25 PM
Hey krasivy, I'd be really interested in your impressions of the LX-3. Thinking of replacing our broken Canon point and shoot with it.

Apart from the AWB playing up a bit every now and then, the LX-3 is an impressive all-rounder camera that I would recommend most people in getting if they had the budget (and it's not too overly expensive anyway!)

(The latest firmware upgrade was supposed to fix the AWB issues, as well as add support for the new external flash - but I have to admit that the results are better than before).

It was a pick between this and a Ricoh GX200 - but because I needed video capture as well, which the LX-3 is able to do 720p @ 24fps, that was the sign to get the Panasonic.

If you wanted to see some sample pics, PM me!

Ken-f
30th January 2009, 10:50 PM
Hey Cods, thanks for that. I knew about the sensor size but never knew it had that effect with the lenses either.

tt4960
30th January 2009, 11:13 PM
This forum is exactly what I needed.

Just looking to get into DSLR photography after many many years of not taken any film, and have 3 Canon Lens which were bought for an old EOS650 many many years ago.

An EF 35-75mm, a EF 70 - 210 mm and a EF 28mm.

What do these correspond to in a DSLR in particular a 450D?

Should I buy just the body or should I get new lenses as well?

Should I buy from one of the big camera houses or a Harvey Norman/JB hi fi or over the net?

Should I buy an extended warranty and if so how long for?

What size memory card?

Gee I feel like a real NOOB, but then, I guess I am.

Thanks.

krasivy
30th January 2009, 11:45 PM
Getting a Canon is a pretty safe bet, and I don't think extended warranty is really necessary.

If I were you, just grab the body only - if those lenses that you have are in good condition.

On a 450D, the crop factor is 1.6x - so just multiply the focal length by that to get the equivalent.

And just shop around to see where's a good deal. From what I've been reading here, Ted's seem to be doing something for cameras lately - just not sure if it's for the 450D or not.

tt4960
31st January 2009, 08:08 AM
Krasivy

Thank you so much!

TT

Cods
31st January 2009, 10:57 AM
Everyone's a noob at something at some stage, unless they're boring and don't try new things.

I've been really happy with the crew here on MacTalk, they've generally been gentle with my newbness...

Odd, but sometimes I find that a more general forum (like this one) is a better place when just beginning than a specialist forum (such as DPReview).

krasivy
31st January 2009, 01:55 PM
It all depends on the community, I suppose :)

The people here at MacTalk are all pretty great, and it's one of the very few forums that I visit frequently now.

(@Cods: got your PM - will get that over to you later today!)

Cods
1st February 2009, 12:50 PM
Thanks krasivy, got 'em.

Nice photos, and thanks for the mix of closeups, street scenes and landscapery (I swear I've walked down that street...).

That's me sold, I reckon.

krasivy
2nd February 2009, 01:08 AM
(Was wondering whether the email would come through - the attachments weren't small when you add 'em up!)

The darker street shot is one of "Women Street" (direct translation) when all the stores are closed up for the day, and after the cleaners have done their rounds... around 4:30am, if I remember correctly.

As for the other one, it's on the other side of the main road where stuff are still open till quite late - taken around 10 mins beforehand.

Glad you liked those shots - because I love the camera immensely :)

FYI, I have the black one - because I think that's the only colour that it looks good in, I swear!

Cods
2nd February 2009, 08:21 AM
I also like the black version of the camera much more than the silver - however a quick search on Amazon (just to get an idea of $) has the silver camera at US$429, and the black version at US$699!

Black anodising must cost... US$270.
I don't think so. Perhaps I should just get a silver one and colour it in with a black texta, simultaneously giving me the better colour AND a significantly lower chance of someone wanting to steal it...

It looks like the black version is favoured so much over the silver that it's on back order pretty much everywhere in the US. A PriceGrabber search has the difference between colours as closer to US$45, which, whilst silly for the cost of a colour choice, is less ridiculous than Amazon.

I don't need it right away (hell, it's a camera, I don't 'need' it) so I'm happy to wait for Panasonic to stamp a few more out and watch the price drop back to below RRP.

Cheers,
Cods

*but I bought it secondhand.

scottgrot
2nd February 2009, 05:10 PM
And these photos are where?

decryption
2nd February 2009, 05:14 PM
And these photos are where?

Who takes photos with a camera? Pffft.

krasivy
2nd February 2009, 05:55 PM
I also like the black version of the camera much more than the silver - however a quick search on Amazon (just to get an idea of $) has the silver camera at US$429, and the black version at US$699!

Black anodising must cost... US$270.
I don't think so. Perhaps I should just get a silver one and colour it in with a black texta, simultaneously giving me the better colour AND a significantly lower chance of someone wanting to steal it...

It looks like the black version is favoured so much over the silver that it's on back order pretty much everywhere in the US. A PriceGrabber search has the difference between colours as closer to US$45, which, whilst silly for the cost of a colour choice, is less ridiculous than Amazon.

I don't need it right away (hell, it's a camera, I don't 'need' it) so I'm happy to wait for Panasonic to stamp a few more out and watch the price drop back to below RRP.

*but I bought it secondhand.

True that no one seems to fancy the silver one - should've just offered it in one colour eh? :p

Yeah... don't remind me. I miss my BlackBook that I sold off to my friend - and it's already got a third owner because he upgraded to a unibody!



Who takes photos with a camera? Pffft.

Go figure huh? :p

Ken-f
18th February 2009, 10:05 PM
Just a few more questions. I'm looking for some filters.....but there is quite a big different in prices. There are some 10 buck ones on ebay, and some 130 buck ones from the camera stores....

What should I be looking for? Should I just get some polarising filter? or a UV filter?

jubilantjeremy
18th February 2009, 10:19 PM
Just a few more questions. I'm looking for some filters.....but there is quite a big different in prices. There are some 10 buck ones on ebay, and some 130 buck ones from the camera stores....

What should I be looking for? Should I just get some polarising filter? or a UV filter?

They're not the same; get a UV filter for each of your lenses (mostly to protect the glass). Don't worry 'bout polarising filters until you know why you need one!

Ken-f
18th February 2009, 10:24 PM
I've seen the differences on wikipedia.....but would the polarising filter act as a UV filter? As far as I know, UV doesn't even travel through glass....which is what got me confused.