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Post by olroy2044 on Sept 1, 2013 16:18:10 GMT -5
I've started trying to learn the quirks of another old lens (combination): the Tamron 04A 75-250 zoom in combination with the Tamron 01A 2X made for Adapt-all II lenses. It is proving a bit tricky. The combined focal length is 500mm actual, and on the 20D is 800mm effective. I haven't totally worked out the proper amount of exposure compensation to dial in, but I'm getting close enough that I am getting useable images that are within the capabilities of the Gimp (and other applications or combinations there-of) to salvage. Hand-holding the beast is a------challenge! But with no tripod fitting, some kind of adapter will need to be fabricated to properly utilize the lens' potential. Working on that. However, on these shots, the tripod would have been impractical: Uncropped ISO 800 f8 1/2000--too fast--stopped the rotor blades--not what I like: This one, the tripod could have been used. I also learned that the extremely long effective focal length is not practical for quickly moving subjects like this one. The very shallow depth of field is a booger to deal with. Close examination of this image shows that not even the entire bird is close to being in focus, even as small as the humming bird is. Of course the bird was only about 7 feet from me. But still, the pic was shot at f11! However, for a handheld shot, I guess it's not too bad. Uncropped Ol(still learnin'!)roy
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mickeyobe
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Post by mickeyobe on Sept 12, 2013 9:29:38 GMT -5
Roy, Something I learned by using my Quantaray 70 to 300mm at 300mm. I would get as close as the lens allowed in its macro setting and was troubled by the shallow depth of field. After a lot of trying various methods without success including stopping all the way down and using flash which I did not like I stumbled upon this. STEP BACK. Get a smaller image in your camera and enlarge it in the computer. I use Photoshop Elements 4. It works beautifully. The Quantaray has become my favourite lens and gets more use than my Pentax DA 12 to 24mm and Tamron 28 to 80mm added together. It is a little tricky to use and likes to search but once I learned about its peculiarities we became bosom buddies. I have some other lenses including Pentax M42's and a battery of Canon lenses all of which I can use with appropriate adapters but rarely do. Pentax K100d. ISO 800. 1/350 at f8. Quantaray at 300mm macro setting. About 3 ft from subject. Then Photoshopped. Mickey
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daveh
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Post by daveh on Sept 23, 2013 20:36:03 GMT -5
It's always a conundrum: what to do for the best. I don't really know those lenses, Roy. I do have a 2x-3x multiplier in Topcon/Exacta fitting. The main unit was the 2x multiplier, the second part was an extension tube which had a removable central cylinder. In place this pushed the lens elements along a little further to increase the magnification to 3x. (Without that central cylinder in place it acted just as an extension tube.) My memory tells me that the exposure compensation was close to 1 stop for every magnification - i.e. 2 or three stops for this magnifier. It has sat in its case almost unused since I bought it about 40 years ago. The results were too soft, and the light loss just too much for all but the brightest of conditions. I would (I presume) have been using it with the 200mm f4 lens (Samigon, I think - possibly another Cosina made lens bearing whatever name the sellers felt like putting on it.) Anyway the long and the short of it is that I gave up on multipliers until I bought the 1.4 Canon matched for use with its professional range of lenses. The exposure compensation is 1 stop, but there is no discernible drop in image quality . I use it with the Canon 50-200 f4 L. I have thought about getting the 2x extender, but it costs almost £400 new. I'm thinking for a mere £12,000 more I can buy the Sigma 200-500 f2.8. (Only joking!) You did well with those shots, Roy. I'm sure the moon would (and did? - I recall seeing a moon shot somewhere here) come up well with that combination. Mickey, I know what you mean about stepping back and "multipying" with the software. However, I find it one of the annoying things with the way things work these days is that we can do just because the final quality we put out is judged on a computer screen with a maximum of 1920x1080 pixels. The photo I put as the latest Q is taken at (just about) true macro 1:1. What is on the screen is almost the size that it is on the "film". I just need a 12 megapixel screen to give it a proper viewing. (I actually can't because I have mistakenly deleted the original by formatting the card in the camera. Pentax, rather "helpfully", overwrite the information with lots of zeros so nothing is recoverable even using the best software. Fortunately I have a 6mp version uploaded to flickr, along with the best of that day's shooting, so at least I didn't lose everything.) I'm not sure if this site shows much of the EXIF. It was taken at f22 - an extra light source (in this case ringflash) is something of a necessity. Even so focus is tailing of towards....well, towards its tail.
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mickeyobe
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Post by mickeyobe on Sept 23, 2013 22:56:25 GMT -5
Dave,
Yours is indeed a splendid photo regardless of the means used to make it.
That is what I strive for but I do not permit myself to become pixilated with pixels. As an almost famous TV chef used to say "I do the best I can with what I've got." and would then go on blithely stirring the pot of soup with a fork.
I have not nor do I expect to make prints larger than 8" x 10" and I will definitely not enter any juried competition in some grand ballroom or hall.
I guess I have finally reached the age of "...und too late schmart." and much prefer now to KISS. For me it is more fun this way.
Mickey
P.S. Next to peanut butter marmalade was always my favourite spread. Now, after seeing your photo I am not too sure. I would hate to see that guy perched on my toast. M.O.
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daveh
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Post by daveh on Sept 23, 2013 23:36:19 GMT -5
It would, though, add some nice animal protein.
The currant is even more disappointing. The flowers are quite ornamental but the fruit never really develops into anything. It probably why the current name is Ornamental Currant.
p.s. I should have added that the lens was the original Pentax 100mm f2.8 autofocus Macro lens, so it does fit the title - not that the autofocus is that much use most of the time. I think the lens came out in the mid 1980s.
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