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Old May 14, 2004, 5:07 AM   #11
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Mike Haywoods comments make me a bit ashamed. All of us here are probably equipment junkies to some extent, and I can't really faultsomeone for wanting to own and use the best equipment even if they're not able to get the best out of it --who is really? It can be a silly pleasure in itselftoown a fine piece of equipment, and that fact can increase the time and effort spent in learning more of the art or science. But even that's not really necessary -- if you like it and are happy using it like a point and shoot, then enjoy it and don't let someone like mediscourage you
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Old May 14, 2004, 5:24 AM   #12
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My 2c:

What is the best? Best at what?
http://www.photozone.de/2Equipment/easytxt.htm#Zuw

Owning the most expensive outfit do not makes you a better photographer... just not too long ago a great master created beautiful prints from just a pinhole camera :idea:

IMO most people don't glue their nose to an artwork and look for CA or sharpness, if they do then they miss the "BIGGER" picture: Fporch gallery is quite creative and I can't fail some folks for not seeing it that way... While I can understand why some photographers might want the sharpest lens to capture the nuances of bird plumage, but I can also recall the days when I had to install Softar filters on my Hasselblad (which can put any "L" to shame) because it was too sharp! No one will want to buy a picture showing the imperfections of their skin anyway.

BTW I also happen to have an 85mm f/1.2 L...
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Old May 14, 2004, 9:48 AM   #13
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MADWAND - THX for the suggestion. I have a 50 mm 1.5 EF ultrasonic Canon lens I haven't used since I took indoor shots over the holidays - would this suffice? I guess I need to reconsdider my aversion to frequest lens changes - maybe the problem is I'm just lazy.....:?

NHL - As always, your posts are very informative and even more insightful. I think the specific area where the Tamron 28-300 struggles the most is in wide angle landscapes on infinite focus - the detail looks a little soft. I'm really most satisfied when I focus on a specific object in the mid and upper ranges.

Here's a a topic I have not see in any post - :idea: - Before I got my Digital Rebel, I seriously considered getting 2-3 different Olympus fixed-lens models to meet all my shooting needs. I have C-730, which like all models, has its weaknesses, most of which can be fixed in PSE. About half of my best selling prints were shot with this camera .The models I would choose are; the C-756 for day time and zooms; the C-8080 for wide angle and large file; the C-5050 for low light. Instead of changing lens, I would just reach for the model that would work best under the conditions. The glass in the Olympus cameras is superb and even before they put the new processor in that Steve reports cuts down on fringing, I was getting really great photos. This wouldn't be any more work (or expense) than carrying around and changing lenses, especially as small as Olympus is getting their units. I'm not saying I'm going to give up SLR's to do this - but I'd be interested in what other in the Forum think.
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Old May 14, 2004, 12:17 PM   #14
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Quote:
I have a 50 mm 1.5 EF ultrasonic Canon lens I haven't used since I took indoor shots over the holidays - would this suffice? I guess I need to reconsdider my aversion to frequest lens changes - maybe the problem is I'm just lazy.....
I guess you mean 1.4, not 1.5 -- I haven't heard of that one. There's also a 2.5 macro. Either one is a great lens, and can be used for comparisons as a reference as to what an "L" lens might give you -- Photodo rates the 50's higher than some other L lenses using MTF measurements. I'm suggesting that instead of jumping in and buying an"L" just because we say they're good (which we do), see how much of a differerence you can see with the 50. If it's not important to you, then don't buy the "L", and be happy with what you have.

I'm not sure that I'd advocate frequent lens changes -- just when I got my 50 1.8, I was switching them around, putting them in my pocket etc., and I dropped the 50 -- that wouldn't have happened ifI wasn't casually switching them around (no harm done, but still...). Others are also concerned about effects from dust/etc entering the camera during such changes in the field. However, I wouldn't let these concerns stop me from using better and more affordablelenses where appropriate.
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Old May 14, 2004, 1:33 PM   #15
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On another note MTF numbers are only good indication as long as the measurements are compared to similar lens with the same general focal lenght:
http://www.stevesforums.com/forums/v...&highlight=MTF

Using an arbitrary 50 and extrapolate the results to long lenses or a wide angles is not really a kosher thing to do since their MTF curves are totally different from one another. Someone posted a link from the luminous-lanscape site before which basically say the same thing... In another word the single number rating are subject to interpretation and doesn't tell the story or the results that you want to accomplish with a particular lens.
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Old May 15, 2004, 9:00 AM   #16
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Hi

I appreciate everyone's advice and suggestions. If you read my post in Has anyone received their Canon 1d Mark II yet, you will know I am growing into this camera. Also I am inmy 30 day money back guaranty on my equiptment. So before I am stuck with something that may not be right, I have the option of returning and getting what is best. My goal at this point besides taking classes on learning the ins and outs of this camera is to make sure I have theproperequiptment. The sales people have been very nice and knowledgable (Ritz Camera), but I like second and third opinions.

To Madwand, I am in the process of becoming an enthusiasts. Being a mother of two and a business owner, I decided to take up photography as a hobby (everyone needs to keep their sanity somehow). I have a Sony cyber shot and a Sony F707 point and shoot. They were both the best cameras when they came out. Everything was automatic and thats what I used. Now I want to take the next step. Yes I know this is a very big step, but I am very excited about it.

Again I appreciate the suggestions and links to read up on more information, I think you all are very kind for taking your time to help me with my goals. :-)




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Old May 15, 2004, 1:02 PM   #17
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I'm always happy to give my opinion and be the center of attention!:lol:

The best advice of all - remember to have fun and enjoy yourself.
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Old May 15, 2004, 10:14 PM   #18
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NHL writes
Quote:
Using an arbitrary 50 and extrapolate the results to long lenses or a wide angles is not really a kosher thing to do since their MTF curves are totally different from one another. Someone posted a link from the luminous-lanscape site before which basically say the same thing... In another word the single number rating are subject to interpretation and doesn't tell the story or the results that you want to accomplish with a particular lens.


I posted that link --it's a good, readableexplanation of MTF graphs. I don't dispute what NHL says above; I agree with it in general.However, it is not sufficient to defeat my recommendations there, and I'd like to comment on that a little further.

Photodo's ratings aren't single numbers; they give many numbers per lens. In particular, for many zoom lenses, they give numbers for the lens at 50mm. These numbers can be compared with the 50mm prime. Will they tell the whole story about the lens performance? Of course not, but they will tell one story -- about some measures of sharpeness at 50mm, and that story is a goodindicator of lens performance. To be clear, Photodo has their own disclaimer about what they cover and don't, and let me emphasize that IMO there are indeed significant factors that are not covered, which will be of interest to some photographers.

I stand behind my claim that the 50mm can be used as a rough guide to the potential improvements via other lenses on the following grounds:

1. It's widely recognized as a good lens, whereas the lenses in dispute in such cases are usuallynot. If you do a detailed comparison and find your lens to be significantly worse than the 50mm (at 50mm), then you know that you can do better, and then further consider other alternatives. The 50mm is suggested as a particularly inexpensive and still useful lens to use to start such comparisons.

2. Photodo's ratings, although not definitive by their own admission, are not in serious question. You need to take a grain of salt with single numbers, but Photodo, as far as I am aware, is still well-respected and a useful guide. Most simply wish that they were able to continue judging newer lenses. Photodo's methodology is based on MTF measurements, which are generally respected in the industry.

3. Photodo shows L zooms with performance at 50mm that is slightly inferior to the 50mm 1.8 II at comparable apertures.

4. Photodo shows that the 50 1.0 L prime has slightly inferior performance to the 50 1.8 II at comparable apertures. (The 50 1.0 wins at F 1.0.)

5. Similar arguments can be made for the 50 1.4 and 50 2.5 macro.

6. If you disagree strongly with 2,3,or 4then just go back to 1 -- that's enough in the case that a 50 mmprime out-performs another lens that you have and are considering replacing. If it does not, then you need to consider 2-4 further, or simply do a detailed comparison of another candidate "good" lens (e.g. an "L" of a lens) vs. the lens that you're considering replacing, or call it a day based on (1).

Photographic comparisons (done using a tripod, same settings, etc.) are the most convincing, and most self-convincing, and obviously the most definitive. I have done some myself with the 50 1.8 II and the 300D kit 18-55 anda current Tamron 28-200 (which is comparable or superior to the 28-300.) I won't comment in detail about my results, because they're not yet finalized. However, they do not contradict anything that I've written so far.

Let me add on NHL's point that Canon publishes (calculated) MTF graphs for their lenses -- they're certainly a useful source. However, they have a number of significant limitations when used to compare lenses. (a) Half of it is performance at maximum aperature -- this can only be reasonably compared when lenses have the same maximum aperture (rare in lineup of a single vendor). (b) For zooms, they show performance at minimum and maximum zoom -- this too canonly be compared among lenses when they share at least one of the extremes. If a lens shows excellent performance at both zoom extremes, then one could fairly reliably guess that it would have good performance in between, but that's still a guess, and in such a case you probably have a clearly superior lens (which is at least rare or expensive). That said, I repeat that Canon's graphs are available and useful.
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Old May 16, 2004, 6:31 AM   #19
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You obviously understand the issues... my remarks where meant as caution for folks who hastily jumped to conclusion based on one final rating out of 5 which is just a grade. There's no doubt on my mind that the 50mm f/1.8 is a fine lens and further proof than "L" lens is not an absolute necessity, there's plenty of others examples...
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Old May 16, 2004, 9:37 AM   #20
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I just wanted to throw out there (for others to comment on) that I have read the Canon MTF charts on www.canoneos.comare theoritically calculated. Not by using the lens and figuring it out, but my analysis of the lens elements and lens construction.

So they should be considered "ideal" numbers that the real world will probably not reflect. Of course, since they are all done this way you can compare them with other Canon numbers. But they shouldn't be used to compare against Pop Photo's MTF numbers (for example) because those are (I believe) calculated by actually photographing the chart and counting the lines (with software, I assume.)

Eric
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