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Old Jan 27, 2009, 2:27 AM   #21
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Carrots,.. and others,... I think the 75-300mm Canon AF is known to be the soft lens. In reading some other sites about telephoto shots, a point was made that anytime you shoot a telephoto shot the shutter speed has to go up with the setting of the lens. The minimum for a 100 mm shot would be 1/mm, so for a 300mm shot my shutter speed should have been at least 1/300 sec, which it was not. This would also be even worse if the focus was set at the max distance or even close to it. Even on a decent tripod, there is a lot of movement of the lense.

However, after looking at many other pictures, and some of the best, all of them have one thing in common. The area of the surface of the moon where the sun hits at a very high angle produces no shadows at all. It is like a very bright light shining on a flat white wall. There is no contrast. The only place where the moon shots look good and in focus is on the edges where there are shadows and contrast.

All in all I've learned alot from this little exersize.
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Old Jan 27, 2009, 12:10 PM   #22
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trigger1937 wrote:
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However, after looking at many other pictures, and some of the best, all of them have one thing in common. The area of the surface of the moon where the sun hits at a very high angle produces no shadows at all. It is like a very bright light shining on a flat white wall. There is no contrast. The only place where the moon shots look good and in focus is on the edges where there are shadows and contrast.
I think you will find that this is only due to the exposure. If you were to reduce the exposure then there would be detail in those areas too. All that is happening is you are getting over exposed areas and thus no detail in those sections. However if you did expose for those areas then you will find that nearly all the rest of the moon will be dark so you have to choose which sections you want clear.
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Old Jan 27, 2009, 3:01 PM   #23
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Mark,.. Yes the exposure is very difficult to balance over the entire surface. I guess that the tools in Photoshop could work on this the best by darkening the highlights and lightening up the dark areas. You can't over do this as this just ruins the shot.

Thanks for the help. Now I'm going back to evaluating the new flash I bought for my XSi. Any suggestions on the best way to test it to check the guide number, or is this really just something out of the past. These Auto ZOOM evaluating unit just couple to the camera lens and make good settings. I've been very pleased with it so far. The biggest limitation I've found so far is the auto zoom only has a max range of 25mm to 85mm which is great on kit lens but not for my 75-300mm lens.

I've seen some great shots taken of birds,etc. with telephoto and they use a fill in flash which worked great. But since mine only goes up to 85mm I don't know how to use it to get correct exposure at 200mm even if I'm with 25' of the subject.

If this question need to be move to a new topic I will do that.
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Old Jan 27, 2009, 3:22 PM   #24
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I would ping it into a new thread so more people will get to look at it for you.
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Old Feb 9, 2009, 5:47 PM   #25
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Spy said, "You can capture a sharp moon at up to a 5 second shutter so set your shutter timing to around 3 seconds..."

not unless you have a reduction gear drive to keep your camera tracking the moon. over the course of even TWO seconds, it moves enough to blur photos, and at 3-5 seconds, the image is hopelessly blurry. i shot some of an eclipse last summer with my 40D (400mm on a tripod), and using the live preview at 10x, i could actually SEE the moon moving across my LCD.

moon shots are best done at about 1/200-1/250 for a full moon. use f/8 for sharpness, and keep the ISO at 200 or so. as the moon waxes or wanes, you'll need a slower shutter; a half moon needs about 1/100-1/125 for proper exposure.
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Old Feb 9, 2009, 5:52 PM   #26
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" for a 300mm shot my shutter speed should have been at least 1/300 sec"

Trigger, that rule applies to shooting handheld; the shutter speed should be at least the reciprocal of the focal length to avoid camera shake with an unstabilized lens. with a stabilized lens, you can go 2-3 stops slower and still get good results. the 75-300 is definitely NOT Canon's sharpest lens, but between f/8 and f/16 it should give you at least decent clarity, especially in the center.
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Old Feb 9, 2009, 10:33 PM   #27
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squirl,... thanks for the info and confirmation. The 75-300 does not have IS, so that is the point of my post. Anyway, you've seen my pictures. Do you think there is something better that I could do.

The real problem with the KIT lenses for the Canon XSi is that they both have a terrible design for manual focus. Even with the "Live View" mode, the manual focus ring is "Just to Course". For example, the manual focus ring has a total angular rotation of about 40 degrees adjustment to handle the entire zoom range of 18mm to 55 mm on the standard lens. When you are at either end, there is only a 5 degree change in rotation to cover the front to rear in and out of focus. When you use the 75-300mm lens, the adjustment is just as course.

Some people might say,... "What do you expect,... This is a low cost AF lens". I would say, "I expect than any Lens that Canon woul sell should come up to their LOGO standards. After all, both of these lenses have an AF mode and a Manual Focus mode.
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Old Feb 10, 2009, 4:31 PM   #28
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trigger1937 wrote:
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squirl,... thanks for the info and confirmation. The 75-300 does not have IS, so that is the point of my post. Anyway, you've seen my pictures. Do you think there is something better that I could do.

The real problem with the KIT lenses for the Canon XSi is that they both have a terrible design for manual focus. Even with the "Live View" mode, the manual focus ring is "Just to Course". For example, the manual focus ring has a total angular rotation of about 40 degrees adjustment to handle the entire zoom range of 18mm to 55 mm on the standard lens. When you are at either end, there is only a 5 degree change in rotation to cover the front to rear in and out of focus. When you use the 75-300mm lens, the adjustment is just as course.

Some people might say,... "What do you expect,... This is a low cost AF lens". I would say, "I expect than any Lens that Canon woul sell should come up to their LOGO standards. After all, both of these lenses have an AF mode and a Manual Focus mode.
You are going to be in a similar boat with any focus ring on a lens where it the focus is not on a geared ring (as found on L lenses or things is Sigma EX etc). Even with my most expensive lens a Sigma 120-300mm f2.8 you only have 110 degrees and as mentioned this is using a geared focus system. MF is not a key part of a lens but it is still usable with a gentle hand however you are working at extremes with shooting the moon.

After a lot of trial and error this is about as good as I can get using that lens with a couple of tele converters making 1200mm.

Going to the shutter speed question, as long as you are using a good tripod then I've seen shots in the 1/30s range but I've never been successful with that speed soI try to keep about 1/100s, but having the tripod and also using remote shutter release are key.


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Old Feb 10, 2009, 10:30 PM   #29
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Mark,... that is a very good shot. Is the teleconvert you have an expensive unit. I know there are some really cheap ones around but I'm sure you wouldn't both since you've already spent the cash for a very good lens. Am I wrong or do I see a small bit of double image as if something moved. I believe you indicated that you used and external shutter release. Was this an electronic RF shutter release or a manual cable. Also, did you make any shots at 1/200 or faster?

In "SPY"'s post he used 1/200 for his shot. It is also very interesting to compare the different views we see of the Moon. I don't know the name of the massive crater which is about at 7:00 on his image, but in my image that crater is at about 4:00. In looking at your shot I can't find it at all so I have no clue what hemisphere you live in. I Have some old 2x converters so I might as well give it a shot.

By the way, now that I remember, when I was shooting in Live View mode, I kept having to re-locate my tripod adjustment because the moom was moving so fast. It was near midnight and the moom was directly overhead and at this angle it is moving as fast as any possible condition for photography.
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