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  1. A number of questions have been raised about the image I started this line of inquiry with. Am I shooting Jpg or Raw? Could the EFCS be the issue? Could the issue be due to the contrast difference between the subject and background? and so on. So let me add yet two image showing the same problem with different backgrounds. Please see the following images. Notice the shadowing around the left side of the subject's head. Originally shot in RAW converted in Affinity Photo to a jpg and cropped. The raw image shows this "shadowing, just like the jpgs attached. I also shoot with a different camera system, (m43) and with a 100-400mm Panasonic lens. I cannot find a similar issue on any of the images shot with the m43 system. Is this common with the 100-400mm GM lens? Or, as I am beginning to think, a defect in my lens? Please note the third image close up of the bird. No shadowing evident in this image taken with the m43 system with the lens at 400mm extension.
  2. Thanks for responding. I never shoot compressed RAW. All of my images are RAW and are full 80mgb. Thanks for the reference on the EFC shutter. I am not sure it relates to the issue I have. The shadow is on one side of the hawk and not top of the image. Paul
  3. Indeed it is helpful. I will review the article referenced later today. I understand that jpeg compression is a lossy compression and can lead to artifacts like the kind I found in my image. But keep in mind that the image had the issue, was a RAW image file, not jpeg. I had to make a reduced size jpeg in order to send it to the Forum. I am wondering if my lens has an issue that needs to be corrected? Oddly enough, on most images, I seem to be fine with the level of sharpness I am getting with this lens.
  4. I am away from my iMac that has the original image, but my recollection is that the image was taken at somewhere above 1/1000 of a second and set on EFC. Usually while walking in the field the camera is set on C2 (BIF) and the base shutter speed is 1/1500. I seldom reduce it below 1/1000. P
  5. I understood the EFC was used primarily to mitigate shutter shock when shooting at slower speeds. Like you, I use it as my default setting no matter how high I set the shutter
  6. I thought I responded earlier to your thoughtful comment. I guess I did not send it. So let me try to re state it here. The image was a jpg, but, the I typically shoot only RAW, and the unedited RAW image file has the same shadow on the left side of the Hawk, and it can be seen in some of the branches as well. I am new to shooting wih the Sony System. Formerly I shot wit a Panasonic G9 and a Panasonic lens 100-400mm lens. I don't recall seeing such shadowing on similar shots of wildlife taken with the Panasonic system.. You also commented on the "sharpest transition in intensity" I understand the comment, I think, but I would be interested in understanding how this could occur, and not be a astigmatic issue? If you have a reference that explains it, I would be interested in seeing it. Thanks for your help, Paul
  7. I shoot with a Sony a7R3 and the 100-400m m Sony GM lens. While I am generally satisfied wit the lens performance, i noticed on some images I am getting a shading along the image as if it is out of focus or is astigmatic. I have attached one of these images reduced in size and cropped. Please look at the left side of the Hawk's body and bring the image up insize on screen and you will see the shadow like area following the contour of the left side of the bird's body. Any thoughts about his would be appreciated.
  8. Issue resolved. I got into the sub menus and somehow, I changed something and now it is working. Unfortunately, I did nt keep track of the changes I made and so, while it is working, I cannot be sure what I did to fix it. That speakes to the issue fo rht complexity of menus and the ambiguity of how they are labled. Thanks again for all who tried to help me.
  9. Poly I set the camera up as you suggested and I now have a button assigned to spot focus (AF-ON). And the Back focus button is assigned to AEL button. That is to give me a choice of Wide focus (AEL) and Spot Focus (AF-ON). Only problem is the AF-ON button will not permit me to change the F stop and the shutter speed varies as a function of the light (Aperture Priority ???). The current setting is F8.0 and and no matter how I set Mode (P, A, S, M) when I push the button for Spot focus, the f is set to F8.0 and the camera is in apparently Aperture Mode. Another issue is that I cannot tell what ISO setting is used. I can use the AF-ON for spot focus if hte object in stationary. I focus using hte spot then release it and click the shutter. And that works so long as the object is not moving. I have a second camera system also set up like this one is with a spot focus (set by menu) . In that camera the spot focus permits me to set aperture and shutter speed, and use any of the Mode settings. I am assuming the my AutoFocus will be more accurate at a larger F stop like F4, is the true?
  10. Thanks to both responders. I guess I read the information about Back Focus Adjustment as you guys did. So I am inclined to think the issue is really an issue with this lens. It seems to sharpen up at 300mm when I stop down to f8.0, But even then it's really not as crisp as I would like. In truth I think this is a design issue for most long zoom lenses. They all seem sharpest at the shortest focal length. My other system is a Panasonic G9 with the 100-400mm lens and it too is sharpest at the shorter FL. However, even at 400, it seem sharper than this Sony lens at 300mm.
  11. JCC, thanks for responding to my inquiry concerning qmycamera and focusing it. After reading your comment I went to the Sony site and looked up their page on Front andBack focus adjustment. After reading it, I think they are referring to NON- Sony lenses. I s this also an issue with Sony Glass? All my lenses are Sony manufactured, and one of concern is the Sony 70-300 G OSS. When I look at the camera and the "Micro Adjustment" item in the menu, it is ON, but if I then select lens, it reports "Invalid with this Lens" So, I am at a loss as to what this all means.
  12. I set my A7R3 up for wildlife and it works fine using "Wide" focus. I then set up focus using back button (AEL Button ) And then set the AF-On button to single spot focus and there in lies the question and concern. When I normally shoot I have aperture set to f8 (becasue the 70-300 G OSS is not very sharp wide open at 300mm) I have C2 set for all of this and ISO floats from 100-800 and I can select a shutter speed. All of that works well until I use the AEL Button for Spot Focus. Now the camera let shutter speed accommodate to give best exposure and the F stop is LOCKED to f5.6 and I cannot reset it. I assume the camera shifted to P mode and favors widest opening becasue usually spot focus is used when the object may be in shadow. My question is, is there any way to change the f stop when in Spot Focus using the Back Button AEL? I tried to do this when the AEL is depressed, but the F remains at 5.6. I tried M Mode same thing, F Locked at 5.6. Any suggestions on what to do here?
  13. I have a A7E3 and several lenses among them the 70-300 G OSS. I find that many of my images are not in crisp focus while others seem ok. I have had several camera systems over the years and never had this kind of problem then or now with my other camera, a Panasonic g9 and 100-400mm Leica lens. The 70-300, using AF-C, cannot seem to auto focus to focus on very distant objects (infinity) Almost every single image shot at infinity is blurred noticeably. I am not sure its any better using my Ziess 16-35 f4 lens at infinity. Problem is size of the objects at infinity are really too small to make a critical judgement about sharpness. If I use manual focus with the 70-300, I get a much sharper image than with AF (set AF-C) and it make little difference how high the contrast in the scene is, they come out blurred on AF-C. This observation raises a question about images shot at closer range. Is this symptomatic of a general focus error or is it a limitation of the focus system in the A7R3, or finally have I a defective camera? Using wide area focus with the A7R3, many of the images shot at shorter distance that I thought would be in focus were less that as crisp as other images shot at similar distance. Bottom line, is this situation indicating a Camera issue that can be fixed, a problem in how I use this particular camera? Or, is it a lens issue with the 70-300 G OSS lens? I am baffled because I get much sharper images with my Panasonic G9 and the 100-400mm lens that I use for wildlife, than I get from the A7R3, which I use mainly for landscapes. Any suggestions and thoughts about this issue of mine?
  14. Have you considered a high quality used mirror lens for Moon shots? A good quality 500mm mirror lens is much easer to carry and set up, and I will bet they are much less expensive than any of the lenses discussed here.
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