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Old Jun 28, 2004, 6:34 PM   #1
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Greetings folks.

I am having some troubles getting sharp pictures, and am not sure what is the problem. I have included a sample of what I usually get when I use my equipment.

Equipment: Digital Rebel, Bausch and Lomb Discoverer 60mm 15x60 Zoom, Manfrotto 055 tripod with 3D head, Cable release.

I had some success with this scope using film, but non with the digital. I suspect that the change in focal length has a lot to do with it. On a film camera, it is a 1000-4000mm lens, on the Digital Rebel, it turns into a 1600-6400mm lens. Mind you, I never stray too far from the low end due to severe lack of light, etc, making it very hard to see what I am focusing on. If I stay in the low end, I can get a very nice sharp picture in my viewfinder, but when I download the photos to my computer, I am alwaysdisappointed. I do try to minimize any camera shake when I am taking the picture, even resorting to bean bags over the lens.

Any suggestions? Do you think it is mirror shake, wrong tripod, etc...I am open to any suggestions in getting sharper pictures.

I would really like to use this scopes at the bottom end for long range picture taking.
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Old Jun 28, 2004, 7:16 PM   #2
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The blue wires are pretty :-). Maybe you could lay it down and cover it with a sandbag and then takesome pictures of something with a lot of depth, like a row of trees.
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Old Jun 28, 2004, 9:08 PM   #3
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Yep. This scope isn't the best, and suffers from nice chromatic abberation in some shots, particularly in highlights. :-)

I have included another shot. This one looked very clear in my viewfinder, but once again, this is what I get.


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Old Jun 29, 2004, 9:35 AM   #4
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So you are manually focussing on the truck?
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Old Jun 29, 2004, 10:25 AM   #5
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Couple observations. First, the image of the truck has elements of both out of focus and motion blur combined with the scope's own chromatic aberrations and purple fringe. There is really too much deviation in both motion blur and out of focus to correct.

The image of the power pole shows that the primary issue here is insufficient depth of field. Had you used a smaller aperture this one should have been well within tolerance. There was about a two pixel out of focus on the pole itself and about a four pixel out of focus on the wires to the left. This difference could only come from depth of field issues. After correction and removal of the purple fringe, the image is well within tolerance.

I believe the primary problem with the more distant shots is coming because of mirror slap. There is a bootleg firmware fix which will allow you to lock up the mirror on the DR and that's probably going to help more than anything else. You may want to seriously consider a Pentax or Swarovski if you want to avoid the chromatic aberration issue.

Here's a link if you have any interest in the firmware hack to allow mirror lockup and ISO 3200 enable.....

http://www.bahneman.com/liem/photos/...el-tricks.html

Lin



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Old Jun 29, 2004, 2:35 PM   #6
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Thanks for your info. Yes I was focusing on the truck.

I bought the Discoverer as a spoting scope, and only decided to use it as a lens afterwards. Its more or less a secondary thing to play around with. If I was serious, I would definitely get a better scope.

I did buy a Samyang 500mm F8 mirror lens because I was really getting frustrated with the whole digiscoping affair,and found it very sharp in comparison. It turns into a nice 800mm lens that I can hand hold at times if I brace myself. Before this, I was starting to doubt my own eyesight, playing with the diopter settings on my viewfinder.

I try to get the smaller apertures, however, I am hamstrung with the very slow f16+ that the discoverer gives me.

I hadn't figured on mirror slap though, and I can see that is a distinct possibility. I have the battery grip installed, and the camera does overhang an awful lot off the scope. However, i am not into hacking my camera yet, for fear of warranty issues. I will still play with it and see what I can get.

Thanks for your replies, once again. Gives me something to play around with now. Hmmmm...maybe if I use a second tripod to stabilize the camera......
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Old Jul 1, 2004, 12:17 PM   #7
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I tried once again this morning, with the same results.....sigh

I tried all shooting parameters and modes, to no avail. I am getting more and more certain its mirror slap. I can focus nicely using the viewfinder, but my shots always turn out blurry.


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Old Aug 3, 2004, 6:42 AM   #8
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Lin said; "After correction and removal of the purple fringe, the image is well within tolerance."

How easy is it to remove purple like that? I have been intending to pick up PS Elements2.

Thanks,

Dave

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Old Aug 3, 2004, 8:15 PM   #9
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It depends on where it is and the type of information in the rest of the image, but essentially it consists of selective masking and either desaturation or color replacement. Because of the issues with some of the new fixed lens high resolution cameras such as the Sony DSC-F828 which tends to produce this fringe in high contrast areas, several people have written PhotoShop "actions" specifically geared toward removing purple fringe. They automate the process and in many cases work like a miracle and are all quite inexpensive and some are free. With Elements you can, I believe, run PhotoShop actions so if it gets to be an issue let me know and I'll post links to a few places where you can find these actions and also a brief tutorial about how to remove them in PhotoShop.

Lin
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Old Feb 11, 2005, 2:41 PM   #10
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The problem is that a bonded element is going bad.(same as mine)

If you unscrew the barrel and look at the part with the rings you'll see the lense that is two piece/bonded,you'll see your problem.

That scope is probably not worth sending in,but would make a nice one if you could order just the new element.

Of course bushnell would like to ream you for that tiny piece of glass,labor(5minutes) and shipping both ways.

I know for a fact that they stock the replacement part,but they wont sell just the part,they insist I send it in for a "ESTIMATE".

Nothing to estimate I said,just send me the part,OH nooo way they said.

Eveybody should know to stay away from these scopes,they "all" eventually have the same problem.

If you have any luck with getting it repaired reasonably,please post.
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