Hi Wm.Would it hurt to blow a little air towards sensor with air bulb? May be a topic for a new thread??
Hi Joules - I agree with your rule of thumb, I was just trying to keep it safe and simple for OP. Since I use crop bodies with crop factors of 1.5, 1.6 and 2.0 it's easier for me always use the 2X factor. Plus, I have read it argued that the smaller pixel pitch of crop bodies actually needs faster shutter speeds than the old rule of thumb to minimize blur. Final reason I tend to use the 2X factor is that I find it hard to do the math quickly in my head. If I've got a zoom lens set at 45 mm I can multiply by 2 in my head in an instant. To multiply by 1.6 isn't so fast. In truth though, if I know I'm going to face a situation where camera shake might be an issue I just grab a body with IBIS or a tripod.Rule of thumb for the right exposure time is 1/(crop factor*focal length) so for a 50 mm focal length on an APS-C camera, you shouldn't expose for longer than 1/(1.6*50) = 1/80 s. Any longer than that and you'll either need a tripod, great image stabilization or enormous luck to get a sharp image.
Hm, I had somehow completely skipped reading the second part of your post that already mentioned the rule of thumb. I totally agree that 2X for a modern APS-C body is more practical, both in accounting for the high megapixel counts and how to calculate it. Sorry for the redundancy in my post, I didn't mean to correct you are anything along those lines.Hi Joules - I agree with your rule of thumb, I was just trying to keep it safe and simple for OP. Since I use crop bodies with crop factors of 1.5, 1.6 and 2.0 it's easier for me always use the 2X factor. Plus, I have read it argued that the smaller pixel pitch of crop bodies actually needs faster shutter speeds than the old rule of thumb to minimize blur. Final reason I tend to use the 2X factor is that I find it hard to do the math quickly in my head. If I've got a zoom lens set at 45 mm I can multiply by 2 in my head in an instant. To multiply by 1.6 isn't so fast. In truth though, if I know I'm going to face a situation where camera shake might be an issue I just grab a body with IBIS or a tripod.
IMHO, a blower can be helpful but I suspect you need to clean the sensor. You have two options: Take it to a reputable shop and have them do it; or, do it yourself. I know that sounds a bit scary but it really is not that difficult, with the right tools. Look at a few videos and get some appropriate swabs, a magnifier and the right fluid. Either way, I think that a sensor clean would help this issue.ok, so here's one more shot from outside. iOS 100, f22, manual focus. If you magnify the image a few times there is actually a few small rings that show and some other "something".... I dont know what any of these are or means. Very much a beginner and was just trying to figure out what the circles showing up in the 1st church picture are form. Tks
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