Zoom lens question...

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Jun 29th, 2005, 09:37 PM
  #1
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Zoom lens question...

Will my 70-200mm f/2.8 lens lose any "speed" if I were to attach a 1.4x teleconvertor? I realize this would no longer make it an effective f/2.8 but does this also play a role in how quick it will autofocus? (if that is what is, in fact, meant by the "speed" of a lens)

I am so tempted to find a way to go out and get the Sigma 120-300mm f/2.8 lens. I am hearing from more experienced photographers that a f/2.8 will make much more difference than the Optical Stabilizer on my 80-400mm f/4.5-5.6 lens. I just don't know which way to go.

I do, however, know that I have quite a few things to pickup before I am ready for my trip, and these things must really take priority over a very expensive lens.

These items include:

1. New Laptop (DVD Ready w/ 60+ GB)
2. Canon 20d body (so I don't have to change lenses so often and also as insurance in case there are any problems with one of the bodies)
3. Tamrac 777 backpack
4. Ballheads for tripod & monopod
5. 2.5 more GB of CF cards (this will get me up to 6MB's and will allow me a bit of flexibility)
6. 3 more camera batteries (this will give me 3 batteries for each camera, as I do not want to underestimate my procrastination abilities when it comes time to recharging the batteries)
7. A really good filter for my sunrise/sunset shots (I already have UV & Circular Polarizing Filters for all my other lenses)

So, it is not looking too good at getting this final lens that I would like.

I would have never imagined that there was so much to DSLR photography...a Nikon 8800 point and shoot would have been much easier but, then again, unchallenging.

Bottom line...will the 120-300mm f/2.8 lens make a huge difference? This is a very highly rated lens by photographers (rating about a 9.3 on Fred Miranda's user reviews). If the 1.4x teleconvertor is going to slow it down, I imagine that I would still be able to get 90% of my shots without it, as it is still effectively, at its longest, a 480mm lens.

If I did get this lens, I would probably leave the 80-400mm OS lens at home and just take the f/2.8 zoom lenses and the Canon 17-85mm IS lens. Not quite sure about the Macro lens, but I would probably take it (I certainly didn't buy it NOT to take it to Africa).

With a laptop, I am probably looking at about 25 pounds in the backpack, but I think I can handle it, even on 6 mile bushwalks, providing the heat doesn't kill me.

Here are the reviews for the 120-300mm f/2.8 lens:

http://www.fredmiranda.com/reviews/s...&cat=37&page=1

For what it is worth, I do notice that the 80-400mm OS lens that I am concerned about did score a 9.5 user rating on Fred Miranda:

http://www.fredmiranda.com/reviews/s...&cat=37&page=2

Just leave well enough alone???
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Jun 30th, 2005, 01:24 AM
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Just leave well alone?

Firstly, why not buy the more inexpensive 350D as the backup body?

Secondly, when a lens is referred to as a fast lens, it's not because of the speed it autofocuses, no. It's a term used to refer to lenses with wider apertures (like 1.8, 2.8) - a wider aperture, as I explained in the long photography thread, allows more light into the lens - it's a wider hole than a narrower aperture - so because there's more light coming in through the hole you can set a shorter (faster) shutter speed and still be able to get enough light in to expose film/ register the scene on the sensor.

Hence the lens is often referred to as a fast lens.

In low light situations, the person with a 2.8 lens might be able to get a speed as fast as 1/60th of a second and successfully hand hold it whereas the person with a 5.6 lens is going to be stuck with a much slower shutter speed and will not be able to hand hold.

I have to say that I think you're going down the more money than sense route on this whole thing. I don't say that to be rude but to try and shock you into stopping and reassessing for a moment.

Throwing more and more money into more and more equipment will not guarantee you the NG style shots you crave - getting really familiar with the equipment you have may do. The more you buy the less time you have to familiarise yourself with all of it (and the more time you'll waste switching between all of it out on safari). Not to mention that you're going to rapidly run out of space for clean underwear let alone other clothing at this rate.

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Jun 30th, 2005, 04:13 AM
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Take a course, Rocco before you buy more stuff. You will learn a lot.

You have mixed your equipment so I do not know if the autofocus will work for you -- if you have a canon teleconverter and a canon lens, the autofocus will work. If you have a canon teleconverter and a sigma lens, the autofocus will not work. In the field, trying to get the shots, I would not want to have to manual focus as that is what takes time. If you will have to do this, you need to spend a lot of time learning to focus to be able to do it quickly and without thinking. If both are sigma, I do not know if it will work. Don't know that much about sigma.

When a lens is referred to as fast, that reference is to the amount of light it will let into the sensor when the shutter is open. The 2.8 lets in a lot more light when the shutter is open than say a 5.6 or an 8 or 11. Because of the amount of light let in, the time the shutter is open to get the shot taken is less. So you get the shot in less time which is why it is referred to as fast.

Putting a 1.4 teleconverter on does reduce the amount of light the sensor gets by one stop. So you will not have a 2.8 with it on. It will be slowed by one stop.

There is a relationship between the shutter speed and the aperture. The lower the number on ther aperture, the higher the number on the shutter speed -- the faster the shot is recorded.

Speed is important because, if you are hand holding the camera, you cannot do it without moving some. Also, the subject may move. The quicker you get the shot, the better probability that it will be a sharp photo. The image stabilization adjusts for some of the natural movement that occurs when you hand hold the camera. It is worth about 2-3 stops. So if you could hand hold and get a clear shot at 1/125th of a second, the is will allow you to hand hold and get that shot at 1/60 ot maybe even 1/30 of a second -- without changing the aperture for that setting.

Aperture relates to what is in focus in the photo and depth of field.

I know you take the dogs out and photograph them. But I might suggest this exercise to better understand the relationships.

Take an inanimate object -- maybe a flower or shrub photo. Photograph it on aperture priority going through all the aperture settings and compare the photos for what is in focus and how long the shutter was open.

One more exercise I would suggest is to do the same shot using all the white balance settings -- you do not have to change the aperture and shutter speed for this. But your camera has several white balance settings that make a huge difference in the photo and it is important to understand this. I found that to be the most important thing I learned in class.

I would not buy the additional lens -- the professional photographers I know are very particular in the lenses they use and do not purchase every one out there. The 70-200 2.8 you have is the number one lens they have. Learn to use what you already have. You will go on several more safaris so, as you learn you can acquire and refine what you take -- this is not a one shot trip for you -- you will always be going back and taking photos.

There were some photos recently and she used a point and shoot camera with about a 438 lens -- I thought they were great-- some of the better ones I have seen posted. She had a very good eye which is something all the equipment in the world cannot make up for. Having the equipment is only a tool to getting the great shots -- knowing what to do with it and being able to compose the shot -- that is what is important.
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Jun 30th, 2005, 05:25 AM
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Thanks for the feedback. I just ordered the 120-300mm f/2.8 as a result.

JUST KIDDING!

I am practicing with my current equipment nearly everyday, as well as reading a book, attending classes at a local camera shop, reading a book on wildlife photography and watching videos (one specifically for the Canon 20d and another for digital photography in general).

Still, a Nikon 8800 would have been easier!

But now that I have gone down the DSLR route, there is no looking back and I am trying my best to learn. The proof will be in the pudding when I am able, in 3 months, to share my photos from 20 days worth of Zambia, Cape Town and the Sabi Sand!
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Jun 30th, 2005, 06:04 AM
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Good to hear you're keeping up the learning. Are your results improving?

Look fwd to seeing the pics when you get back from the first DSLR trip!
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Jun 30th, 2005, 06:21 AM
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I just have to say thanks to Rocco, Kavey and others for these wonderful photography threads. I haven't yet bought my first digital, but have gone from the Canon G6 to the Rebel XT and now I'm sure I'll end up with the 20D! I love everyone's sense of humor here, and your willingness to share and teach. What a pleasure it is to read these messages!!!
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Jun 30th, 2005, 06:45 AM
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Roccco, have you weighed that camera bag, fully loaded? Perhaps you should be carrying that on your walks with the dogs! Good workout...

mpkp and kavey have super advice, as usual. I want to underline a couple things that they said:

1) take a course- perhaps you can find a weekend course. The classwork and homework will be invaluable. Check out the listings at community colleges, or ask at a good local camera shop

2) if you can't schedule a course, you will need to do some "DISCIPLINED" practice. mpkp suggests a way to do this...I'd also add on (1) see if you can find a good book which will walk you through all the settings on the 20D in real English...if that fails, use the manual. take test shots using all these functions, and then IMMEDIATELY, look at the results on your computer. See how varying the aperture changes the depth of field on various shots, and see how changing the shutter speed also provides different effects, including camera motion/vibration blur! Digital now allows you to refer to all the settings with each image, so now you have a way of comparing results. When you open images, size them up (don't judge by the thumbnails) and zoom in really see the differences. While you are at it, work with your tripod and monopod as well as handheld, and see how slow you can go with shutter speed using each setting.

3) As mpkp says, get used to shooting in aperture priority. the aperture setting determines depth of field, and many photographers consider it the fastest way to still have control in settings like safaris.

ONce you have done this, I'll think you'll be over the feeling that you need any more equipment. Shoot a bunch of wildlife shots at f2.8 and I think you will see why. I know some people love this for special effects (eg just the animals eyes are in focus) but most people find that f2.8 does not provide the depth of field they desire. Special effects are great, but this is an expensive and heavy (literally) price to pay for selective focus.

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Jun 30th, 2005, 06:54 AM
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Rocco

also make sure that you understand how the different settings on the OS "optical stabilisation" works.
Since I have a Canon I am not sure if it is exactly the same with the Sigma but on the Canon you have to understand the different settings and when to use them
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Jun 30th, 2005, 07:00 AM
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Tashak

Would definitely agree that 2.8 is so wide that it's going to provide a REALLY shallow DOF and that's just not suitable for every photo.

(Rocco, depth of field is about the depth of the area that is in focus, for example a deeper depth of field might mean that everything that sits between 5 feet and 20 feet away from me is acceptably sharp in focus, a shallow depth of field might mean that only objects that sit between 5 and 5.25 feet away from me are sharp and everything nearer and further away from me than that is blurred).

I really adore shallow depth of field (and posted some examples that I particularly love of shallow DOF macro/ close up images on another thread of yours.

Even so, there are certain images where I want a lot more than just the nose and eyes in focus.

And even where I DO want that shallow depth of field, it's extra effort too because I have to be a lot more careful to focus on just the right part of the object if only a narrow plane will be in focus than I do if the whole thing is gonna fall within my focal plane. It's about making a conscious decision about just what is going to be in focus in an image which is predominantly blurred.
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Jun 30th, 2005, 09:24 AM
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Kavey,
Just curious...do you go all the way down to f2.8 to get this effect? I've done it at f4 and more ofen 5.6, but have never liked my results at f2.8. Your photos are beautiful, so you clearly know more than I do!
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Jun 30th, 2005, 01:48 PM
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Tashak, not on my DSLRs, no as I haven't had a 2.8 lens on any of our trips - too expensive!!! And zoom lens that's 2.8 all the way through the focal length is way too huge for me to use easily either. I couldn't manage it!

And I really don't think that an EXTREMELY shallow DOF is well suited to animal and landscape shots, which is what I take most of.

Where I really love shallow DOF is in macros and close ups. We've recently bought a 100mm fixed length macro which is a f2.8 lens and I do adore the shallow DOF we can get from that.

If I had a donkeyboy to carry my camera gear for me, both on the journey out and back and during the trip itself, I'd take this lens along too and use it for occasional macro studies and close ups but... given that I'd rather limit my total amount of camera kit, I stick to just a couple of lenses and go for one wider zoom and one telephoto zoom and that's it.

So when I want shallow DOF in close ups, instead of using the wider lens close up to the subject I use the telephoto from a distance, that gives a shallow DOF anyway... and just make do with that.

Believe me, I really don't photograph in an organised manner to be thinking about exactly what shutter speed I must use for this or that. I don't want to waste my experience time on that kind of thinking. I just go by instinct. I do have sufficient knowledge and understanding to be able to previsualise what impact my choices in aperture etc will have on my results so I'll swing towards wider or narrower apertures to achieve that vision but that's as far as it goes.

I worry that Rocco has convinced himself that it's the equipment that will deliver the results he's after and is therefore building himself up for a disappointment.

A good photographer should be able to get good images from whatever equipment they are using. They could get even more from equipment with more features or better lenses etc but... what they get from basic equipment is strong too. We have a series on TV at the moment where three pro photogs are given a camera each (in each episode), one gets a pro DSLR, one a point and shoot and one a mobile phone camera! They are all producing some great shots. The mobile phone ones may not be sufficient quality to print enlargements etc but the images themselves are good, if you know what I mean.
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Jul 1st, 2005, 06:50 AM
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Not to hijack Rocco's thread, but since you're on here, Kavey, I also have questions about photo equipment. I plan to buy the Canon 20D. It will be my first digital, but not my first SLR. But I cannot afford L series lenses. And I can't imagine hauling more than two lenses on a trip. I also can't see myself buying a second body, and my film SLR broke a long time ago...Can you advise me on two good lenses to take/buy? I'd like one for distance, of course, and one obviously for when I'm lucky enough to be closer to my subjects. I don't want to burden myself with too much stuff. Also, what is a better option for a camera bag - a sling type or backpack? Decisions, decisions...

Thanks for any tips!
Sharon
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Jul 1st, 2005, 08:56 AM
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topping...
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Jul 1st, 2005, 09:03 AM
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Sharon,
Long though it is, can I suggest you read through at least the first two thirds of this thread, http://www.fodors.com/forums/threads...4&tid=34562663, which may help with some of your questions, after which I'd be delighted to answer any further questions.
Please note though that I'm not a professional photographer so my advice is just based on my own experiences...
In terms of 2 lenses, for our 20D we use the following two lenses:
Sigma 18-125 mm
Canon USM 75-300 IS (not L glass)
These two are enough for a safari in my book. I'm not saying I couldn't make use of other lenses if I a) could afford them and b) could carry them around with me but that these two suffice given our desired balance of skill levels, finances and requirements.
I don't think I could personally feel comfortable without some kind of backup but I can totally understand that finances are unlikely to permit a second 20D.
We're lucky that we have a D70 that is our current backup. When we just had that one DSLR then my latest film SLR was our backup.
What I would suggest as a backup is one of these options:
Look for offers on the 350D
Look for a second hand 10D
Buy a (new or second hand) reasonably well-specced non SLR digital camera
Kind Regards
Kavey
PS I recently posted some pics I took last year in Africa using a D70 DSLR, I don't know if you've seen them?
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Jul 1st, 2005, 09:22 AM
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Kavey, thanks. Yes, I did see your wonderful pics. I esp. loved the elephant shots. I have read sooo many of these digital photography threads and they have me very confused, hence the question to you. I will look at the one you've listed, maybe I missed that one. I also will look into the lenses you have. I do have a film point and shoot, an Olympus 140. I will look into other options, though. I was considering a Canon G6 or maybe one that's a little less expensive. (In addition to the 20D.) Again, I'm just getting into the digital realm. Do you have a recommendation on carrying your gear on travels? I've seen two bags that I like that are reasonably priced, by Tamrac. Or Tamac? Anyway, one is a backpack style and one is a sling over the shoulder style. I supposed it's just a matter of preference. At any rate, thanks for all the input.
Sharon
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Jul 1st, 2005, 10:03 AM
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I haven't tried a Tamrac bag so I can't compare but am VERY happy with our various lowepro rucksack camera bags.

We have a Mini Trekker Classic which is probably the one we use the most. We can get two SLR bodies, 4 lenses, batteries, filters etc into it or other combinations of laptop, charger units etc.

We also have a Micro Trekker 200 which is also pretty roomy for a single SLR with a couple of lenses.

Note: I'm talking about the regular sized lenses not the huge ones that are the size of a hippo's back leg!

And we bought a Dryzone 200 for use in the Antarctic, it's harder to access but has similar capacity to the Mini Trekker.

I prefer a rucksack backpack as, one the few occasions where I'm carrying it on foot, I find it much better for my back and hips than one that sits on a single shoulder. On driving safaris it can sit open on the floor or seat next to me so everything is easy to access. It does mean I have to stop and take it off my back to access anything during a walking safari but I prefer that to the back pain that I got from previous regular shoulder strap bags.

It's defintely a matter of preference though!
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Jul 1st, 2005, 11:33 AM
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Cooncat,

Not to hijack your hijacking of my thread and not to proclaim to be the expert that Kavey is, but I think a good zoom lens for your safari would be a Sigma 80-400mm EX Optical Stabilizing (OS) lens. The EX means that it is Sigma's best series of lenses and the OS acts the same as the IS feature on Canon lenses. Plus, it is black to match your camera and therefore it will not look like your camera has been gored by an elephant tusk!

This is the best zoom lens that I know of under $1000. Here is some pricing (copy and paste)

http://www.nextag.com/serv/main/buye...m_Telephoto_80

I have had very good experiences with Sigma 4 Less.

For your shorter lens, a Canon 17-85mm IS lens may work out well for you. Here is pricing on that lens:

http://www.nextag.com/serv/main/buye...=Canon_EF_S_17

It will add about $400 to just buying the 20d with the lens that it comes with (an 18-55mm lens, I believe), but considering it is IS and is a little longer on the zoom, it is probably money well spent.
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Jul 1st, 2005, 11:56 AM
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I'll check 'em all out! And how dare you hijack the thread that I hijacked from you! (BTW: I hope you saw my clarifications on the hunting/conde nast posts. This is one case where I truly want my own thoughts clarified!)
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Jul 1st, 2005, 12:00 PM
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Please... I feel uncomfortable to be referred to as an expert on a subject that is merely a hobby for me. I enjoy it and have spent much efforts trying to understand it better and do it better but... I'm woefully underexperienced in the vast range of equipment out there to be considered anything but a friendly guide...
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Jul 1st, 2005, 12:06 PM
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Kavey....Your shots look awfully good to me...!!!!
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