Understanding Lenses

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#1
Hello, im about to purchase my first DSLR (350d or D50) and i dont understand the lenses at all.

A while back i purchased a pair of binoculars and got to know how the lenses are marked then. 10x50 would be a 10x zoom and 50mm across the top - this is the amount of light it lets in. This isnt the case with camera lenses is it?

The higher the second number the bigger the zoom isnt it? but how do i work out what is what?

My current camera is a prosumer compact and has a 6x zoom i want something a little bit better but havent a clue what is SLR lens is similar to a 6x zoom :shrug:

Any help or links would be mucho helpful :)
 

Joe T

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#2
http://www.usa.canon.com/html/eflenses/lens101/focallength/

The above will help you understand focal length. (similar to zoom)

Its slightly more complicated than that. Focal length gives you an angel of view. That angle of view dpeneds on howbig the imaging sensor is. For film, the above comparison will work. For a DSLR, you need to mulitply the focal length on a lens by 1.6 (usually) to get the equivalentfocal length shown above (this is known as the 35mm equivalent).

You 6x zoom probably had a 35mm equivalent focal lngth of 38mm to 228mm, if that helps.

Aperture is something for another post. :)
 

CT

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#3
LOL. When you ask a question you pick a good 'un Lee. :D

Massive subject mate and don't want to over-burden you with info at this stage, but have a look at Joe's link. It'll probably help to know that a focal length of 50mm is considered the 'standard' lens, and one which gives the same view in the viewfinder as you'd see with the naked eye in terms of object size and perspective. Shorter than 50mm is going wide angle and longer than 50mm is considered telephoto, i.e. objects become gradually magnified as the focal length increases.

You're obviously considering a zoom as your first lens which isn't a bad idea, they can be very useful 'general purpose' walk around lenses, but most people go for a mix of zoom lenses for convenience, and fixed focal length (prime) lenses for better optical quality.

Just don't rush into anything. You'll get plenty of advice here before you buy. And be warned now, it can get very expensive! :D
 
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#4
That animated whatdoyoumacallit thing shows it quite well tbh. Ideally if i want to better what i have now on zoom i want something bigger than 300mm, which isnt cheap :(

Ive looked in Jessops and the prices are through the roof!! USM L and imagestablizing all send the prices the wrong way :LOL:

The only reason im looking at a zoom first is that its the only thing letting me down on my current camera. But looking at things i dont think im gunna be able to afford the upgrade if it means a pricey lens is in order.

I was considering the Canon EOS350d which is £500 with the kit lens. I thought that would be a nice general purpose lens but it doesnt seem the case?

How much should i budget for a decent 300mm lens then? i dont need USM/L but imagestablizing would be nice. Also autofocus is a must.

Does AF eat at my battery life?
 

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#5
What do you want the lens for? a 300mm prime would be great for some motorsport and wildlife, but waaay too long for general use.

AF and IS are both powered from the camera battery so they do affect battery life, but it's safe to say that battery life with modern DSLRs is phenomenal and it isn't something to worry about at all. :)
 
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#7
Ill be using the lens for wildlife and planes :cautious: my brother is a plane spotter (I mean Aviation Enthusiast :cautious:) Im just let down by 6x zoom, it just falls short of the mark so anything slighter better than that should be ok.

I can deffo stretch to £180 for a lens, i was expecting to pay twice that if im honest :D

The other type of photography i enjoy is landscape (even though Marcel will tell you im not the country type though :LOL:) so ill eventually need a wide angle lens, but ill be doing this less often so will probably wait till i can afford it before purchasing that.
 
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#8
Joe T said:
A half-decent budget 300mm is the Sigma 70-300 APO. Its around £180 and is good for the money. Canon also do a range of well priced zooms, but the Sigma is supposed to be good for the money.
I've just ordered one of these to replace my old sigma 100-300mm that doesn't want to talk to the new camera! I've heard seriously good things about this lens - Sigma do a non-APO version too for about £30 - £40 less, but the chap in the camera shop today said to me to not even consider it - the fall off in quality is considerable and the APO version is the way to go.

Remember also Lee that on a 350D at least that 300mm lens will give you an effective length of 480mm which you will notice is a considerable gain on your existing camera.

I've just paid £155 for that Sigma lens mentioned above, if that gives you a guideline. I'm sure it could be tracked down cheaper than that on the web too.

As and when you come to look for a prime lens (the fixed length that JoeT mentioned earlier) then the one a lot of the guys on here use and are impressed with is a Canon 50mm f1.8 - apparently superb image quality.
 

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#9
When you are paying a lot of money for a lens it can be a comfort to have a look at used prices on ebay. Most lenses hold their value quite well so upgrading in the future won't mean losing a lot on what you have already bought.
You will end up spending more and more eventually though :) welcome to DSLR.
 
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#10
another little thing to consider if you are thinking about the sigma is that thier quality control isn't always the best. so if you can make sure you try the lens before you buy it, amazing value if you get a sharp one :)
 
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#12
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#13
Well in theory Sigma, Canon, and Nikon provide international cover on their lenses, the exception is the bodies - so although I wouldnt wish to experience it, you shouldnt actually have any problems if something did go wrong - should just be serviced in the UK by themselves or an authorized service centre.
 
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#14
Warspite said:
Well in theory Sigma, Canon, and Nikon provide international cover on their lenses, the exception is the bodies - so although I wouldnt wish to experience it, you shouldnt actually have any problems if something did go wrong - should just be serviced in the UK by themselves or an authorized service centre.
Thanks for that - worth knowing.
 

Steep

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#15
Witch said:
Sigma do a non-APO version too for about £30 - £40 less, but the chap in the camera shop today said to me to not even consider it - the fall off in quality is considerable and the APO version is the way to go.
The guy in the camera shop is spot on Witch, I started with the non APO version and upgraded very quickly to the APO, the difference is startling.
 

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#16
The only thing I would say to Mancunian Lee about the Sigma is that it's a bit slow to focus and can lose the plot in low light which might make it unsuitable for fast moving aircraft photography. It's also a bit soft at the 300mm end but then they all are at that price range.
 
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#17
I think ill order one of these even though i dont have a DSLR yet :p means i pull my finger out to buy one then :LOL:

It calls the lens a macro on there though, whats that all about? isnt it a telephoto?
 

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#18
Have you looked in the for sale section here on the forums?

There are Nikon and Canon DSLRs for sale in there. You need to decide which make you are going with to order a lens :) (unless you have and I missed that)
 
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#19
Im after the 350d but keep seeing good deals on the D50 that are very tempting! if i got the D50 i think id always wish id of gone for the 350d :)
 

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#20
Mancunian Lee said:
I think ill order one of these even though i dont have a DSLR yet :p means i pull my finger out to buy one then :LOL:

It calls the lens a macro on there though, whats that all about? isnt it a telephoto?
Manufacturers discovered some years ago, that when the lens is focused to it's closest distance, they could add a 'macro' settting which involves all the lens elemenst moving forward to give you an even closer focusing distance. Usually you turn the focusing ring through a slight resistance to set the 'macro' setting.

It's not a true macro lens. Real macro lenses give a life sized image on the sensor of tiny objects and critters. Nevertheless it's a really useful feature to have in a lens and will enable you to get very reasonable close-up shots which you couldn't otherwise tackle.
 
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#21
That sounds great :D

The thing that worries me, is that the Canon equivalent lens costs a hell of a lot more.normally this would put me off but because a lot of people seem tolove it ill get it. How come its so much cheaper?
 
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#22
If your talking about the 70-300 IS, then the reason it costs so much more is because it has IS. It has similar image quality to the Sigma, but the IS basically moves the elements in the lens around to stop the effect of camera shake. Thats the only reason it costs more. Canon also make a non-IS version of the 70-300 (an OK lens) and a 75-300 (IS and Non-IS). The 75-300 has been discontinued, but its a terrible lens, with lots of softness above 200mm and not very good IQ.

Unless you need IS, get the Sigma :D

Leo
 

CT

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#23
Well, independant lens manufacturers have to pitch their prices under those of the likes of Canon and Nikon. They're there to give people a more affordable choice. Usually the build quality of the 'own brand' lens is far better, but you pay a price for it. It should follow that the 'own brand' lenses will be superior optically but it isn't always the case. Among the independant lens makers Sigma and Tamron have a fine reputation for producing good glass. You just need to do your research on any particular lens before you buy, and the collective experience on this site can usually point you in the right direction. :)
 
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#24
My personal opinion on IS would also be that if you're learning, get a non stabilized lenses - that was you learn to take a steady pic without help. As and when you go on to IS logic says it will make the results all the better.

I bet 14 people come along and tell me why I'm wrong now! ;)
 
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#25
Witch said:
My personal opinion on IS would also be that if you're learning, get a non stabilized lenses - that was you learn to take a steady pic without help. As and when you go on to IS logic says it will make the results all the better.

I bet 14 people come along and tell me why I'm wrong now! ;)
Ive been doing that for years :p

Ive seen Steve's (am i allowed to mention Steve :cautious:) IS lens in action and i have to say it was very impressive! even at full zoom the image hardly moved in the viewfinder when i wiggled the camera.

Way out of my budget though :LOL: :LOL:
 

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#26
Check out the 'Web Links' section on this forum - there are loads of links there to help you to find out everything you need without you running the risk of asking things that have been covered six million times already.

Lenses, exposure, apertures, shutter speeds, ISO settings and how that correl;ates to digital cameras - it's all there (I just checked).

Go on - have a look.
 
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#27
I understand all of that through using my camera, but with it being a compact and a fixed lens ive never got round to pickinb up what it all means. Will deffo have a butchers at the web links section though :)
 
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#28
Im hopefully going be buying a camera on wednesday now :) looking at Jessops i have two options that look ok.

Nikon D50 + Nikon 18-55mm + Sigma 70-300mm twin lens kit = £509

http://www.jessops.com/Store/s34867...aspx?&IsSearch=y&pageindex=1&CatId=481&comp=y

I assume this is the none posh Sigma lens as mentioned and ill need to throw a few more quid in to get the better one?

Or

Canon EOS 350D Black + EF-S 18-55mm Lens = £499

http://www.jessops.com/Store/s28045...aspx?&IsSearch=y&pageindex=1&CatId=481&comp=y

Both about the same price but ill be getting the other lens with the D50. I have a 6mp camera now and have never felt the need for more, so i wont miss what ive never had. Im not a very good photographer (yet:p) so a basic DSLR seems the right decision for me.

For me personally, do you think its worth paying the extra for the Canon and then buying Sigma lens when i have a bit more cash? personally im not sure, i think ill be happy with the D50 but if the Canon is worth paying the extra for then ill do it.
 
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#29
Get a D50 you won't regret it, i prefer it over the 350D size wise and price and feel, go and have a play with both and see what you prefer.

I have just bought a D50 with kit lens and a Nikon 70-300mm lens and they are great, i don't have VR/USM as i can't afford it but to be honest these DSLR's are so fast in comparison to your existing prosumer compact you may not need it, of course there are exceptions to this such as low light and longer focal lengths.
 
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#30
Im liking the D50 more and more, plenty of places saying the 350d is better but i think saving the £100 is worth it for me.

Does it come with memory? im not expecting it to!! is the cheap SD cards ok to use? i know you pay for what you get but £13.49 for a 1gb SD card is tempting :D
 
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#31
No it doesn't come with any memory, the main downside of the cheaper SD cards is their speed, ideally you want something 80x and above, 120x or 133x being ideal, it just means the card handles data faster so when the camera is writing to it it is better, so you may get a longer burst of pics at full speed before the camera slows down to write to the card.

I just got one of these to go with my 120x kingston 2gb card, great value, lifetime warranty and corsair make very good memory.

http://www.scan.co.uk/Products/ProductInfo.asp?WebProductID=255296

or the 1gb version.

http://www.scan.co.uk/Products/ProductInfo.asp?WebProductID=255295

Good fast large memory doesn't have to cost the earth.
 
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#32
Mancunian Lee said:
Im liking the D50 more and more, plenty of places saying the 350d is better but i think saving the £100 is worth it for me.
i'd be very impressed if you could tell the difference between the pics from either of them. (except maybe a little bit in low light shots)

go for the one that makes you happy.
 
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#33
I suspect when you try both out in the shop one or the other will just feel right in your hand. I've personally always got on with Canon - I have quite small hands and their cameras tend to have everything in the right place for me. Others find the same thing with Nikon. It really is just down to personal taste I think. Research prices for lenses for each brand before you buy as well - it's easy to forget that with SLR's there's always something else you want to add! ;) (or indeed - several something elses!!)
 
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#34
Like Canon being better supported.

I was in Jessops today - the lies they tell people!

As I went in, some guy had brought in a magazine cutting with a review of the Sigma 70-300 APO Super II (or something like that). Jessops only has the APO DG Macro - fine, newer model. Slightly more expensive, but fair enough.

Then the guy says how the Tamron 70-300 macro is better...tells him its £99 and gives him a big long sales pitch...

"And the sigma only works on digital bodies" - first lie!

Then, he says, "shall I get them?"

at this point its worth me noting that he had said how the macro capabilities of the lenses aren't 1:1.

He goes to the back room, and brings the sigma, tamron, and a tokina 100mm 2.8 macro - not exactly what the guy asked for.

Then he goes and double checks all the prices (after the guy has decided he definately doesn't want the £300 tokina, and he has talked up the tamron some more)

"Oh, it appears the Tamron is £199...sorry" - so now he's told the customer how good the more expensive Tokina is...then how good the more expensive tamron is, and lied to make the least expensive sigma seem worse :D

I went in there, took some photos with the sigma (tried it with my camera in store :D) and made the guy regret using Nikon by showing him how he could of used stopped down metering on his old Ai-S lenses on a Canon, compared to no metering on the nikon :D

Well...thats why I think Jessops SUCKS!!!!!

Leo
 
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#35
Yeah i feared they are pushing the DSLR bodies so they could make money onthe lenses. I went in today and bought a D50 and kit lens, ill be buying my lenses online but today they were trying to pressure me into buying them there and then and at hiked prices :banghead:
 
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#36
Mancunian Lee said:
Yeah i feared they are pushing the DSLR bodies so they could make money onthe lenses. I went in today and bought a D50 and kit lens, ill be buying my lenses online but today they were trying to pressure me into buying them there and then and at hiked prices :banghead:
congrats (y) look forward to seeing some pics now :D
 
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