more lens questions

neea · Feb 18, 2007

Hey everyone,

I'm making a list of goals and a list of what I need to achieve these goals.
This includes a new lens or two, and a Digital Rebel XTi.

So far I only have the lens that came with my Rebel 2000 (28-80mm).
I've used a friends 300mm lens quite often and always feel like I need more. For my current goals I think I would prefer around the 400mm.

I'm getting very confused and overwhelmed with all the info I've read today on different lenses.
From what I understand, if I did NOT get the kit lens for the XTi and used my current lens I would be without the wide angle (is that right?). This is completley ok with me because I've been doing landscapes for a few years and want to get closer. I lenses that will work with both cameras and fit my 58mm filters.

I'm also very confused with terminology.
Things like IS, USM.
And how does the size of lens affect aperature (I'm always hearing about this and have no idea what it all means)

I would also like to start doing maco. Is a lens necessary for this or are there any converters, filters, etc that would be cheaper (I dont want to do alot yet so just want something cheap until I decide if I like it).

I'm looking for the best line up of equipment and am really interested in things like converters for telephoto etc.
Any suggestions? Opinions? What works best for you?

If you need any more info on what exactly I plan to do just ask.

Thanx everyone.

EDIT: Lens hoods. what size etc. what would work best.

Torus34 · Feb 18, 2007

Wow!

Once again, let me make an appeal.

There are several TPF members who are super lens wonks. You know who you are. I don't intend to name names here.

Wouldn't it be nice if someone [or someones -- plural] took the time to write a few articles on lenses and had them published on TPF?

That way, newbees to the mysterious world of lenses would have some place to turn for all sorts of lens information.

Any volunteers?

neea · Feb 18, 2007

Great idea!!!
Perhaps we could start making a list of nominees who we new people feel may be qualified. Then if they agree (and really.. you'd feel so flattered and sorry for us poor unknowledgeable people, how could you refuse.)

Spread the wealth of knowledge!!!!

sothoth · Feb 18, 2007

neea said:
From what I understand, if I did NOT get the kit lens for the XTi and used my current lens I would be without the wide angle (is that right?).

Assuming you have a lens that's not designed for a digital camera this is true. The digital rebel is a sensor that's smaller than 35mm film, so you have an additional multiplier you use to calculate the focal length. For the canon cameras, it's 1.6, so your lens would have a longer focal length on that camera.

neea said:
I'm also very confused with terminology.
Things like IS, USM.
And how does the size of lens affect aperature (I'm always hearing about this and have no idea what it all means)

I'm not one of the lens guru/geeks, but I've recently been through all this myself... {2 hrs has passed, just got back from dinner with my wife}

To put this in overly simplistic terms, each lens manufacturer has terminology for the "standard" and "high" quality glass. You should find out for each manufacturer what they call it, it will be different in each case. For example, Canon sells several grades, I'm pretty sure the "DO" class is the best, with DO standing for diffractive optics.

USM is Canon's term for ultrasonic motor, which is a faster and quieter autofocus technology. Sigma has their version called HSM (hypersonic motor) and since I have HSM/non-HSM and USM/non-USM I can tell you it's helpful to have if fast focusing is important to you.

IS is image stabilization. I'm currently debating whether or not its worth the extra money, but for sure for the Canon lenses with IS built-in, you'll get noticeably less blurring. You have to decide if it's worth the extra money for each lens, though.

The max aperature is generally effected by two major things: the quality of the glass in the lens (better glass absorbs less light and therefore lets more get to the sensor) and the focal length and/or number of glass elements in the lens. Also, zoom lenses have smaller max aperatures in general (relative to non-zooms (primes) of the same focal length with similar quality glass in them.

The larger the max aperature, the more light gets to the sensor, so the better they are at photographing fast moving things like sports or birds flying.

neea said:
I would also like to start doing maco. Is a lens necessary for this or are there any converters, filters, etc that would be cheaper (I dont want to do alot yet so just want something cheap until I decide if I like it).

When you go lens shopping, look for lenses that have macro functions built in. For example, the tamron 18-200 and the tamron 28-300 are decent lenses that both do macro work, so you don't need to buy anything extra necessarily, esp before you know if you're serious about that or not

As for specific suggestions, opinions will vary widely depending on what you shoot. I have an ultra-wide (10-20mm) from Sigma, an f/2.8 28-70, and I'm in the market for a 70ish-300ish right now. I like to have a minimum number of lenses that covers most of the range I need (from wide to tele). There are single lenses that do almost all of that (like the tamron or sigma 18-200) however those tend to be softer and have more distortion at the lowest and longest focal lengths. If you don't mind that, it's not a bad way to start out. If your tastes get more refined as you develop a particular style or type of photography you like the most, you can go back and buy lenses that are ideal for what you do.

Hope this helps. Between the time I started this reply and the time I got back from dinner to send it, there are probably a lot of the lens gurus who've chimed in as well.

SaSi · Feb 19, 2007

A correction about the DO designation on the two Canon lenses that have it.

The DO lenses are shorter and lighter than normal L lenses. This carries an advantage for people needing a shorter and lighter lens, but the image quality is visibly worse than the normal L lenses. Especially bokeh. And they are significantly more expensive than the others.

For the telephoto you mention, you should get the EF 400/5.6. It is a very good lens and has a moderately affordable price. Or you could get the EF 300/4 which offers IS and offers a wider apperture for you to get a 1.4x TC attached and reach 420mm with good image quality.

Alternatively, you could get the EF 100-400 which is more versatile since the zoom will allow you to frame different scenes without moving from your position. The image quality would be comparable to the EF 300/4 + TC.

You could always get a cheaper lens, from the consumer range, like the EF 70-300/IS which is much cheaper and not as good as the L series. You can either save money that way, or lose money (if you later decide you wanted the better glass).

Don Simon · Feb 19, 2007

Excellent advice there, but just one issue: As you pointed out some manufacturers like to give their more expensive glass special names or designations, but it's not the only way to tell what's good glass. In particular they tend to apply those terms mainly to zooms, which would give you the impression that the zoom is optically better than the primes. Primes and some zooms that are not labelled "L", "Limited" or whatever term the company uses, may still be just as good.

sothoth · Feb 19, 2007

ZaphodB said:
Primes and some zooms that are not labelled "L", "Limited" or whatever term the company uses, may still be just as good.

Truer words have never been spoken. Especially when you're shopping between versions of a lens from two different manufacturers. God only knows whether their designations for glass quality give you ANY basis for real comparison.

Price can be a guide but not always. Generally the lenses Canon makes (using them just as an example) are quite pricey and I'm not convinced that always translates to any better quality. There are exceptions to that of course, the most obvious being that Tamron and Sigma don't have in-lens IS, yet Canon does, which may be worth the huge price increase even if the optics are the same.

KaraM · Feb 19, 2007

I have found this website to be a good resource in comparing Canon lenses. I haven't found a really good source of information for other brands (yet).

Big Mike · Feb 19, 2007

Be sure to try the 300mm lens on a digital body before thinking that it's too short for you. As mentioned, the Rebel XTi & similar camera have smaller sensors...which give then a 'crop factor'. This doesn't actually change the focal length...but it does change the Field of View...which makes it 'feel' like a longer lens. So that 300mm will feel like 480mm on the digital body.

The F number (aperture setting) is a ratio of the focal length and the actual diameter of the hole formed by the aperture blades. A bigger aperture (lower F number) is desirable because it lets in more light, which give you a faster shutter speed. Wider apertures also give you a shallower DOF. However, to have a larger max aperture...the lens has to be bigger...especially with zooms. This makes the lenses bigger and heavier.

sothoth · Feb 20, 2007

KaraM said:
I have found this website to be a good resource in comparing Canon lenses. I haven't found a really good source of information for other brands (yet).

A great site, thanks for posting it... and they DO review other lenses on there:

Sigma
http://www.the-digital-picture.com/Reviews/Sigma-Lens-Reviews.aspx

Tamron
http://www.the-digital-picture.com/Reviews/Tamron-Lens-Reviews.aspx

The reviews are very Canon-biased, which I can't criticize too much (because I usually agree) but the reviewer compares lenses from Sigma/Tamron that cost 1/5 the price of the "comparable" Canon lens. If money was no object, I'd buy the Canon, too, but for many of us we buy the best lens we can afford, and that ain't always the Canon.

Alex_B · Feb 20, 2007

SaSi said:
For the telephoto you mention, you should get the EF 400/5.6. It is a very good lens and has a moderately affordable price. Or you could get the EF 300/4 which offers IS and offers a wider apperture for you to get a 1.4x TC attached and reach 420mm with good image quality.

It is generally advised that this lens (300/4 L) works particulary well with the Kenko Teleplus 1.4x PRO.

It appears the quality is equal or better than with the Canon converter.

Any converter beyond 1.5x does not really meet the image quality one wants ...

neea · Feb 20, 2007

Wow. When you dont logon for a day or two things start to pile up.
Thank you all for your replies!!!
I've learned something new... however I'm still a little confused (dont worry. its not your fault. i will always be confused!!

)

To BigMike: I have tried the 300mm on a digital body (dont know exactly which one though) and that's how I know that it leaves me feeling like I need more.
For example: If I'm sitting on my deck and a humming bird flies in.. this lens is GREAT!!!
If I'm out camping and birds are in random trees or ducks are in the water and I'm on shore... it feels a little short.
Perhaps when I make the plunge to buying a lens... you can be my shopping chaperone.

Thanx again to everyone for your replies. The more I learn the more I realize I need more books to read and webpages to search for.

Don Simon · Feb 20, 2007

Based on these focal lengths and the kind of shots you describe, I'd also factor in the cost of a big solid tripod and head.

Big Mike · Feb 20, 2007

Based on these focal lengths and the kind of shots you describe, I'd also factor in the cost of a big solid tripod and head.

That's a good point. A lot of people don't realize that telephoto lenses really don't do well when only hand held. 300mm is about the limit...and even then, the consumer 70-300 lenses aren't very fast (need lots of light) and a fast 300mm lens is heavy. Longer than 300mm and it becomes even more important to use some sort of stability device. It may be that you lie on the ground while shooting...or use a tri or monopod...but it would be a waste to spend a ton of dough on a lens...only to get blurry photos because you don't properly support it.