Davejwatts From United Kingdom, joined Dec 2005, 42 posts, RR: 0 Posted (10 years 4 months 2 weeks 5 days 11 hours ago) and read 3858 times:
I am using 300D with a 75-300mm IS lens, however I have been having a few problems with it as some of the shots are blurry, it may focus on the front of the aircraft but the back is blurred and some are not of a brilliant quality. I use it on apature priority about F8 and change the ISO setting depending on the conditions. If anybody could help with getting the most from my lens it would be really appreciated!
Sulman From United States of America, joined Mar 2004, 2041 posts, RR: 28
Reply 1, posted (10 years 4 months 2 weeks 5 days 10 hours ago) and read 3853 times:
Got any examples? Are these early efforts with the lens? What focal length are you shooting at? It can take a bit of time to get used long lenses, and to develop an understanding of the strengths and weaknesses of your setup.
I'm surprised your seeing DOF problems at F8, though it's not impossible. More likely you're seeing some sharpness issues on the edges of the image, which can happen. It's a good lens, keep trying and you'll get the hang of it.
It takes a big man to admit they are wrong, and I am not a big man.
Oly720man From United Kingdom, joined May 2004, 7144 posts, RR: 11
Reply 2, posted (10 years 4 months 2 weeks 5 days 10 hours ago) and read 3852 times:
Like all things it's practice, practice, practice.
Depending on the aircraft and its distance from you the depth of field at F8 may not cover the whole aircraft so it may not all be in focus.
If you're going to change the ISO to keep at F8 you will find that it will get more grainy at higher ISO.
If you're taking photos at this time of year, there is not long in the day when it'll be really bright enough to get a high shutter speed to freeze any action and stop motion blur when at F8. The usual rule of thumb is that the shutter speed must be less than 1/focal length so at 300mm you're going to have to use 1/500 or 1/1000 sec to get decent photos and avoid camera shake. If you're looking up into the sky you may only be able to get 1/640 or 1/800 at F8 (well I was yesterday with a 400mm lens) so looking at aircraft close to the ground it will be darker so the shutter speed will be lower.
A tripod or monopod may help keep the camera steadier.
AndrewUber From United States of America, joined Jul 2003, 2528 posts, RR: 32
Reply 8, posted (10 years 4 months 2 weeks 4 days 16 hours ago) and read 3739 times:
I had that same camera / lens combination, and found that the F stop "sweet spot" is in the F8 and F9 range. Try shooting in M mode, set your aperature to F8 or F9 (as long as it's a fairly bright day outside), and adjust the shutter speed instead of ISO. The lens will produce some good images - and the entire aircraft should be in focus. Leave the IS switch "ON" and you can get sharp images all the way down to the 1/200th range. In daylight conditions - always shoot at ISO 100. 200 and above and you'll get quite a bit of grain out of the Canon Digital Rebel.
Here is a shot taken at ISO 100, in gloomy conditions, at a slow shutter speed (1/100th I believe). With IS turned on, it kept the image nice and sharp.
Far more importantly - have a look at your photos. In order to get them accepted, not only does the image quality have to be good - but the images must be centered and level. The three shots you posted are good starts - but you need to crop the shots to make them more centered - and ALWAYS level a shot (if there is some ground reference in it).
Another thing I'd suggest is shooting in RAW. If you can get a good RAW editor (such as Capture One - it's easy to use), you can do so much more with your images during processing - it's incredible. You can salvage dark or overexposed shots - and sometimes even soft photos.
If you would like further help, you can e-mail me through one of my photos or just ask here on the forum!
As it turned out, I didn't have my focus point selected correctly. It was set so that the camera chose the best focus point automatically. This resulted in it randomly focusing on the tail or nose instead of the center of the frame. You may need to adjust the focus point so the center red led is selected.