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MacHeadCase
May-15-2005, 07:14 AM
Hello again! I would like to ask a few questions I have about lenses. I have a new Canon Digital Rebel XT (EOS 350D) and I like to take pictures of wildlife and, darn it!, I am completely mesmerized by close-ups (macrophotography...) so just for fun I have been looking up, off and on at lenses.

What I found at first is that there are a lot of types of lenses out there! (I looked at Sigma and Tamron lenses. There must be other brands, I suppose...)

One type I saw is the IF kind, i.e. as you all know Internal Focus. What I would like to know is what are the advantages of buying a lens that is IF? What are the disadvantages? (My guess here is that they cost a LOT?...)

Thank you all for your input! :):

wxwax
May-15-2005, 07:22 AM
Mac, you have specific lenses in mind?

MacHeadCase
May-15-2005, 07:38 AM
Oh dear... This will be a long term project for sure I just don't have the finances right now to go all out on this. I was thinking that I would try to buy myself a new lens every year.

I am so lost with the info I have right now! :D Like for macrophotography and the like. A stronger more powerful lens that my EF 75-300mm f/4-5.6 III USM is pretty straightforward.

So I really don't know how to answer your question other than I am open to options but I really can't afford those Pro lenses. Unless I buy the winning ticket at the lottery! :D

I am trying to grasp this IF concept, what it is exactly, what are the advantages, etc., see if there are reasons for me to consider this type of lens... If the price is prohibitive then I will promptly discard this from my mind! But I would still like to know what this is exactly. I have always thought that a lens moves (or must move) as you focus...

:rofl

wxwax
May-15-2005, 08:28 AM
I guess I'm not following you, my bad. I'm not familiar with "internal focus" as a distinguishing factor between lenses. You have a link?

For macro work, have you looked at the Canon 100 f2.8? Here's a review. (http://www.photo.net/equipment/canon/100)

And here's a link (http://www.fredmiranda.com/reviews/) to feedback on a bunch of lenses, if you haven't already found this site.

MacHeadCase
May-15-2005, 08:37 AM
See how mixed up I am? IF stands for Inner Focus! So it's my bad! :D

An example, not because I was necessarily thinking of buying it or anything but just because it is an IF lens, 28-135mm f3.8-5.6 Aspherical IF Macro (http://www.sigma-photo.co.jp/english/lens/standardzoom/28_135_38_56.htm).

BTW why Aspherical?

Thanks for your input wxwax! Much appreciated! :thumb

MacHeadCase
May-15-2005, 08:42 AM
Ahh! Upon reading the product's page more closely, the description says it all, concerning Inner Focus:

An inner focus system provides high performance and convenience. The non-rotating lens barrel perfectly suits the matched petal shaped lens hood.

Eric&Susan
May-15-2005, 11:03 AM
I'm kinda in the same boat as you (lens lust, no money!!:rofl ) I've been looking for somtime now and I think for the money I've decided this is what I want:

http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=183198&is=USA

At almost $600 it won't break the bank but will still give me some reach and quality. Maybe this will work for you also:dunno

Eric

DavidTO
May-15-2005, 11:24 AM
I'm kinda in the same boat as you (lens lust, no money!!:rofl ) I've been looking for somtime now and I think for the money I've decided this is what I want:

http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=183198&is=USA

At almost $600 it won't break the bank but will still give me some reach and quality. Maybe this will work for you also:dunno

Eric

That's a mighty-fine lens. Check out the Buy and Sell forums at fredmiranda.com (you have to register) and pick one up used.

MacHeadCase
May-15-2005, 12:34 PM
My photography background is from 35mm film in the 70s with a Pentax Spotmatic II (that I still have BTW and is in as-new condition, not one single scratch!... haven't used it for years but I just can't bring myself to get rid of it...). And even then I was fascinated by macrophotography but never had gotten around doing anything about it back then...

I just started using a digital camera last year with the EOS 300D and taking the time to look around here and there, I find that there was a lot of manual or semi-manual settings I never even tried! I didn't have too much time either so I have that as an excuse! :D

So all of this to say that trying to get to understand the new lens technology is quite something! Thanks for the suggestion, guys I am looking into all you post here! http://idisk.mac.com/macheadcase/Public/foolz/signthankspin.gif

Eric&Susan that lens looks awesome!

USAIR
May-16-2005, 09:02 AM
Take a look Here (http://www.bobatkins.com/photography/digital/10d300dlenses.html)
And Here (http://www.slr-lens.com/) & Here (http://www.patrickmurphystudio.com/canoneos/index.htm) too

Hope this helps

Fred

MacHeadCase
May-16-2005, 09:16 AM
Thank you very much for those links USAIR! Very helpful indeed! I have bookmarked them for reference! :thumb

Lucky Hack
May-17-2005, 04:37 PM
I think I may know what you're talking about,... Some lenses use what is called a "hypersonic motor" this uses soundwaves to focus the lens which makes them faster than the older style which used an electric motor to focus the lens. And yes, they are more expensive, but all my lenses use this new technology and they are an absolute dream!

hoping this message finds you well -Ian

MacHeadCase
May-17-2005, 04:42 PM
Gosh the membership is nice here! Sure glad I found this place, Ian! :D

What if I use only manual focus? Would that widen the compatible lenses available to my camera (EOS 350D Digi Rebel XT)?

The reason I stopped using the automatic focus was that sometimes the focus was calculated on the wrong object and I thought I would have a higher percentage of good pictures that way... As far as knowing if I was right about the percentage, the jury's still out on that one. :rofl

wxwax
May-17-2005, 04:54 PM
You'll find it's difficult to consistently accurately manually focus with the new generation of digital cameras, even the pro bodies. The image you see in the eyepiece isn't big enough, and doesn't have the focusing aids of the film cameras.

leebase
May-18-2005, 12:36 PM
Internal Focus means that the outer lens elemement doesn't turn when you focus. Which is nice, particularly when you want to use a circular polarizing lens.

Wildlife -- I feel sorry for you. That's one of those "need expensive lenses" areas. Long and fast. :)

Lee

MacHeadCase
May-19-2005, 05:24 AM
Hi leebase! Thanks for the reply to both you and wxwax!

Ok got that for the inner focus thingy. I suppose an added bonus is that the same quantity of light passes through since the length of the lens barrel doesn't move... :D

That's one of those "need expensive lenses" areas. Long and fast.

And yeah I found that out just by gathering some info on lens prices!... My god!!! :huh

Quick, gotta become a CEO somewhere! :D

MacHeadCase
May-19-2005, 09:38 AM
I have another question on lenses here. I was just leafing through some free photo mag we get in camera shops around here, PhotoNews, I saw this article and I quote:

...Tamron had created a new design that was lighter and even more versatile than my previous lens with its wide 28-300mm range, light weight and macro capability. Needless to say, I was thrilled."

The question I have is this: How can a zoom lens like that have macro possibilities? :scratch

Lucky Hack
May-19-2005, 09:55 AM
I have another question on lenses here. I was just leafing through some free photo mag we get in camera shops around here, PhotoNews, I saw this article and I quote:



The question I have is this: How can a zoom lens like that have macro possibilities? :scratch

I don't know what the specs on that lens are but the thing that gives a lens macro possibilities is a short minimum focusing distance. I have the Sigma 150mm it has a minimum focusing distance of 38mm, where as their 300mm telephoto has a minimum focusing distance of 200mm. Even if you double the 150 and double it's focal length to match the 300, its still only 76 mm instead of 200mm. Hope this helps...

MacHeadCase
May-20-2005, 07:05 AM
Just wanted to let you all know that I am now convinced that automatic focus is totally awesome! Yesterday I went by the Saint-Laurent river in Verdun and I took some pictures and these I would NEVER have gotten them using manual focus!

Here's an example: Seagull in Verdun (http://www.dgrin.com/showpost.php?p=108417).