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16

You appear to be using your lens (100-400/5-6.3) with the aperture wide open. I would expect the glow in your photos to be significantly reduced or absent stopped down to about F8. Many lenses "glow" when used wide open, especially in bright light with high contrast. It is likely associated with spherical aberration and is typically reduced or completely ...


11

The fact you're seeing this with two very different bodies suggests to me it's in the lens. Long zooms tend to have a bunch of elements (anywhere from a dozen to twenty, in my experience). No lens coating is perfect, and no lens surface is perfect. Every time light passes through an air-glass or glass-glass interface at an element surface, there's a small ...


5

Your issue probably has nothing to do with focus or how sharp your lens is at various focal length/aperture combinations. You're using a 1/160 exposure time with 300mm focal length on an APS-C size sensor. Camera movement is almost certainly what is causing most of the blur you see. If you use the same ISO and open up the aperture three stops to f/5, your ...


3

Indeed I didn't see but one is C and the other is CS so that's why the extension tube of 5mm was working. One of your cameras is C-mount with 17.526mm registration distance, the other is CS-mount at 12.526mm. There is a 5mm difference in the registration distance of those two mounts. You need a 5mm extension tube to use your C-mount lens having a ...


2

You've got a dirty lens. First, alcohol. IPA, ethanol. Use that with a microfibre cloth. That should dissolve the oils, but you want the cloth to pull it off of the glass and into the cloth. Don't reuse sections of the cloth. Then, a little Deionized water and soap- a tiny tiny tiny smidgen. Again, just enough to be a surfactant. Wipe the lense elements ...


2

It's not motion blur. The blur at any particular point seems to be diffused evenly in all directions. This points to poor alignment of the lens. Possible causes of poor lens alignment could be: An IS/VR/VC/etc. element at full deflection. Lens based image stabilization works by slight changes in the centering and/or tilt of the stabilizing element. This ...


1

All lenses are debased by aberrations, two of which deal with color. The lens maker endeavors to mitigate by crafting the lens using multiple lens elements. Most commonly, chromatic aberration displays images with a rainbow colored edge effect. This is caused by the fact that each color has a slightly different focal length. The violet image falls closer to ...


1

Super crisp at f/14 and maximum zoom, then you're asking a bit much of a kit zoom lens. Any lens will start to show weaknesses as you move toward the extremes; a zoom to either limit, very large and very small apertures, the edges and corners of the frame, sometimes even noticeable at the ends of the focus range. All these weaknesses will in general be more ...


1

I'm so sorry to hear what happened to the lens you borrowed. But dropped lenses happen. It appears the lens has been severely misaligned due to the shock of being dropped. Lenses can usually be realigned by a skilled repair technician if nothing is mechanically broken and the range of adjustment allows for any slightly bent parts. This is something not even ...


1

Without a tablet: Fuzzy-Select the background, so that you have a selection that ends near the sharp edge. Select>Grow by one pixel so that the selection is on the edge. Select>Border by about the width of the blur you seek to make a thin selection that straddles the edge. Intersect this with a more general selection (or use the quickmask and paint ...


1

You need to feather the selection/path a few pixels... select menu>feather


1

There are some rather unnatural halos that hint that the camera's internal sharpening goes up to the secret "11" mark: There is no real purpose shooting "raw" if you don't intend to spend significant time on the picture later...


1

Your first example shows the limits of optical viewfinder based PDAF using a dedicated AF sensor array independent of the main imaging sensor combined with the limits of the AF motor of your lens. The system is a so-called "open loop" one. The "ideal" focus position appears to have been somewhere between the third and fourth of the seven frame sequence. ...


1

The mirror isn't the only source of vibration, the shutter causes vibration also. A more solid tripod will help, as well as weights hung on the tripod to minimize the vibration. What tripod are you using? Post a picture of your setup. I did some tests years ago, unfortunately, none with mirror lock-up. http://www.suncoastcameraclub.org/Tips/Tripods.pdf


1

Given the asymmetric blurriness (lower left > upper right), some lens element is probably out of alignment. I suspect a floating element, such as used by image stabilization systems. I doubt a properly functioning image stabilization system would cause that amount of blur. Though you deny dropping the camera or lens, you do admit to "the odd light knock". ...


1

Tamron manual VC instructions below. Note in particular: 1. Turn the VC switch OFF when using tripod. 2. The VC mechanism may introduce errors during long exposures. 3. When the shutter button is pressed down halfway, it takes about 1 second for the VC to provide a stable image. 4. When VC is not used, set the switch off. How to use VC mechanism 1) Set ...


1

I've just come across this (now almost) 9 year-old question. There is some good information in these answers, but many are quite old now, and none really answer the OP's original question: Can software auto-detect image focus? After reviewing the posts here, I found an application called Fast Raw Viewer that has at least a partial solution.


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