|
Post by Romy Ocon on Jul 21, 2008 10:15:11 GMT
I'd recommend that you test a long lens first for focusing issues with your DSLR before committing purchase. master, any tips on how to test a long lens? what one needs to bring? what one needs to do? what one needs to check? what one needs to ask? thanks 1. For AF accuracy, try the "Battery Test" - set up three AA batteries in a diagonal line to you and shoot the middle battery using AF at or near the lens's minimum focusing distance (for thinnest DOF). Use the lens at full zoom and wide open. The middle battery should be sharp, otherwise there is an AF issue. Here's a recent thread at DPR where Hawkman (Gene) uses the battery test to check the AF of his 40D: forums.dpreview.com/forums/read.asp?forum=1019&message=284654182. If the lens AFs correctly, you can then test the optics. Most lenses are sharp at 1 stop down from wide open. Shoot a detailed object at full zoom - one at wide open and the other at one stop down. Make sure you have enough shutter speed if hand holding. The mark of an excellent lens is shots at wide open are as sharp or almost as sharp as at one stop down. 3. If the lens passes the the AF and optics tests, inspect the glass for any imperfection. Make sure all switches are working properly too.
|
|
|
Post by Toto Gamboa on Jul 21, 2008 20:46:01 GMT
great master Romy. tnx!
|
|
|
Post by Ralf Nabong on Jul 21, 2008 23:49:13 GMT
|
|
|
Post by gearguru on Jul 23, 2008 5:41:23 GMT
I'd recommend that you test a long lens first for focusing issues with your DSLR before committing purchase. thank you mr. ocon for this advise...will surely test it out before i commit anything. main reason why i'm highly considering getting it locally albeit the higher price point
|
|
|
Post by Neon Rosell II on Jul 27, 2008 3:33:21 GMT
Finally I was able to go back to JT Photo to have my lens' firmware updated to rectify the glitch with the 40D's AI servo shutter rate. Got the back focus issue fixed as well. Hopefully I'll have a chance today to test it again on some birds. Here are the before and after calibration battery shots I did at the shop. Before@150mm, f5, 1/100 sec, ISO 3200, AV priority, OS On, On board flash, Handheld, 33% crop Battery test on the Sigma 150-500mm @ 150mm. There is a slight back focus noticeable. the batteries were spaced diagonally at approximately 1.5 inches apart. @500mm, f6.3, 1/60 sec, ISO 3200, AV priority, OS On, On board flash, Handheld, Full Frame There is a very noticeable back focus on this focal length. the batteries were spaced diagonally at approximately 1.5" apart. After@150mm, f5, 1/100 sec, ISO 3200, AV priority, OS On, On board flash, Handheld, 33% crop @500mm, f6.3, 1/50 sec, ISO 3200, AV priority, OS On, On board flash, Handheld, Full Frame No available light to test it on different apertures just wide open.
|
|
|
Post by Romy Ocon on Jul 27, 2008 3:48:15 GMT
AF looks great now, Neon..... now go get some terrific feather detail at 500 mm wide open. I hope your copy turns out well, as I'm just about to get one myself in Nikon mount (plus a D300 too).
|
|
|
Post by Teddy Regpala on Jul 27, 2008 5:26:20 GMT
AF looks great now, Neon..... now go get some terrific feather detail at 500 mm wide open. I hope your copy turns out well, as I'm just about to get one myself in Nikon mount (plus a D300 too). Not a D700? ;D
|
|
|
Post by Ariel Jimenez on Jul 27, 2008 5:46:03 GMT
It's nice to know JT can fix af problems. I'll be eagerly waiting on your next field test with this lens sir Neon.
|
|
|
Post by Ding Carpio on Jul 27, 2008 6:57:53 GMT
It's nice to know JT can fix af problems. Yep. They sure can do. Call me "Nitpicker" but I once had a very slight focus problem with my Sigma 10-20 I got from JT and Jerome was nice enough to calibrate it as I watched. It took less than 30mins. BTW. Here's a link to a very useful focus test chart. focustestchart.com/chart.html
|
|
|
Post by Ariel Jimenez on Jul 28, 2008 2:39:22 GMT
It's nice to know JT can fix af problems. Yep. They sure can do. Call me "Nitpicker" but I once had a very slight focus problem with my Sigma 10-20 I got from JT and Jerome was nice enough to calibrate it as I watched. It took less than 30mins. BTW. Here's a link to a very useful focus test chart. focustestchart.com/chart.htmlThanks for the link Ding.
|
|
|
Post by jonathandael on Aug 14, 2008 2:47:49 GMT
nice review sir.. any inputs or suggestions if i were to consider this or the 50-150 or the 170-500? i'm more for image quality.. i don't really mind if it's heavy..
|
|
|
Post by tina mallari on Aug 14, 2008 2:57:16 GMT
If you want excellent image quality ... Canon is the way to go <--- just a suggestion lang naman po kuya JON ;D ;D ;D If you are a Nikon user, then buy a highly rated Nikkor lens <-- don't even know what their lenses are called. HEhHhEhEHheHe Lens reviews. This is where to check lenses out .... www.fredmiranda.com/reviews/Neon admit it ... the image quality of the 300mm f/4L IS is much better than the sigma 150-500 di ba ;D
|
|
|
Post by jonathandael on Aug 14, 2008 3:21:10 GMT
haha! i like your attitude tina! but i won't bend.. LOL! i was born a sith eh.. teka, do i know you? bakit kuya JON tawag mo sakin? i know a lot of mallaris and only 1 named tina. di naman siguro ikaw yun diba?
|
|
|
Post by Teddy Regpala on Aug 14, 2008 3:36:16 GMT
nice review sir.. any inputs or suggestions if i were to consider this or the 50-150 or the 170-500? i'm more for image quality.. i don't really mind if it's heavy.. From what I heard/read: 170-500 - bad 150-500 - good 50-500 - better
|
|
|
Post by jonathandael on Aug 14, 2008 4:49:24 GMT
hmm.. but the 150-500 is newer, right? the 50-500 is 3 yrs old already. interesting..
|
|
|
Post by Neon Rosell II on Aug 14, 2008 10:28:17 GMT
If you want excellent image quality ... Canon is the way to go <--- just a suggestion lang naman po kuya JON ;D ;D ;D If you are a Nikon user, then buy a highly rated Nikkor lens <-- don't even know what their lenses are called. HEhHhEhEHheHe Lens reviews. This is where to check lenses out .... www.fredmiranda.com/reviews/Neon admit it ... the image quality of the 300mm f/4L IS is much better than the sigma 150-500 di ba ;D Yes, of course this lens has no match against the canon primes. The 300 with a 1.4x or a 2.0x TC still has a better IQ. This lens is still to soft for birds but if you are going to use it for sports then this lens is not bad at all because you have the zoom to play with. I still haven't tried this lens after the AF calibration though. Will post an update when get paroled.
|
|
|
Post by oscar cablao on Sept 27, 2008 20:22:37 GMT
|
|