Soft when lens opened up

Bushnell Trophy Xtreme Spotting Scope

Overview
Bushnell Spotting Scope has extra power for extra range; its BaK-4 Porro-prism design delivers magnificent clarity in a traditional design. The multicoated optics ensure maximum light transmission for the brightest and take the images more colorful and clear. If you are searching Bushnell Scope that can be used for different activities, you should consider Bushnell Trophy Xtreme Spotting Scope Review.
The highly refractive BAK4 Porro prisms diminish spherical deviations for increased edge-to-edge sharpness and help progress depth of view. This combination of optics and coatings creates a spotting scope that produces clear, bright, highly contrasted images with the exact color transmission.
The rubber-armor structure stands up to demanding use. This scope is 100% waterproof and fog proof for wet hunting conditions. It also Comprises compact tripod with window mount, compact soft case, and waterproof hard case.
Specifications

• Brand:Bushnell
• Viewing Configuration:Straight
• Magnification:16-48X
• Power Variability:Variable
• Objective Diameter:50 mm
• Close Focus Distance:25 feet
• Length:13 inches
• Weight:31.4 ounces
• Field of View:125-60 feet/1000 yards
• Eye Relief/Exit Pupil:16 mm/ 3.1-1 mm
• Optics Coatings:Fully Multi-Coated
• Glass:BaK-4
• Focus System:Focus Knob/Single Focus

Feature Analysis

• Porro Prism Lens
  Though many optics producers keep on trying to transform roof prism lens, Porro prism lenses are more affordable and light-efficient. These Porro prism lenses can display images with better contrast than roof prism variations. This is how Bushnell Spotting Scope is more reliable and affordable for its high-quality performance.
• 20-60×65 Zoom Magnification
  The wide range of magnification allows user flexibility for long-range view finding. You can observe details with 65x zoom for long range objects. But, you can still enjoy an increased field of view with 20x zoom. This is used when separating the areas for closer zoom viewing later on.
• 65x Lens Light-Gathering Capability
  This advanced magnification lenses can light gather at long distances. The Bushnell Trophy 20-60x 65mm Waterproof Spotting Scope resolves this issue by designing 65x zoom lens in a way that brings 17% more light than most high-zoom lenses.
  If you fully read Bushnell Trophy Xtreme Spotting Scope Review, it will support you how to setting zoom for longer distances images.
• Waterproof Construction
  When you go out in nature, this waterproof construction anticipates you about rain or even snow. It is pretty obvious that any liquid that leaks into your scope will detract from the overall image. But many people do not consider the effects of concentration on the inside of the lens.
  This spotting scope is actually water and fog proof not only for outside moisture but also prevents lens fogging from risky temperatures.
• Fully Multi-Coated Optics
  The multi-coated lenses prevent any reflections in the glass that can delay your view. The sunlight at certain angles can cause reflections from water or wet surfaces that prevent the clear view of the images. That is why; Bushnell uses multi-coated lenses to remove any kind of reflection.
• Well-designed Equipment
  The tripod often needs to hide from animals, and the scope cases also need to protect their insides from both jostling and the outside elements. The Bushnell Trophy XLT comes with both a hard-side case and a soft side case. The hard side case protects you from outside damage and a soft-side case protect you from a bumpy road when you are riding.

If the chain is loose I would definitely tighten it up to remove the sloppiness of the drive. That will in turn help you to accurately find the sweet spot that is currently eluding you. And you have to work fast because you do not want to overheat the motor.

The gear linkage in the lens has more than likely seized, you will need a specialist to handle the repair, but before you proceed ask for a estimate.

Hi Robert,
First of all, thank you for posting your question here at Fixya.You may try the steps below to resolve the issue.
Assuming that the disc is good.
1.Clean the lens. -Sometimes because of dust and any fine foreign objects the optical lens can'tread any disc. If you have a CD Lens cleaner, play it to the unit. If this isnot available you may manually clean the optical lens. Open the cover andgently clean the eye of the lens by smooth,clean,soft cotton buds. Be carefulwhile doing this, just a gentle stroke only.
2.Check the ribbon - Checkthe ribbon connected to the lens from the main board for scratch, damage. Once it has anopen line then of course the lens can't read the disc, this is because of themovement of the optical lens back-and-forth. Also try to erase the contact by pencileraser. If you've done the steps above and the symptoms still there then thenext step requires you a little knowledge in soldering technique and readingthe ohmmeter.
3.Check the spindle motor -Check the spindle motor that spin the disc with an ohmmeter. You can test itusing the ohmmeter (x1) even it is connected on the lens assembly.Good motor - reading should be fairly high and itwill spin. Bad motor-reading will drop to low resistance and will not spin or spin slowly.
HopeI helped you.
Have a nice day!
Thanks for using Fixya.

You didn't state whether you are using it on an APS-C or a full-frame SLR, but that lens is known to be very soft and unsharp especially at the edges until you stop it down below f4. It also exhibits strong vignetting until you stop it down.

The effects are far more noticeable when using a full frame sensor.

Some production examples will be worse than others, and some users will notice the unsharpness more than others. You clearly find the performance to be unacceptable, but it is mentioned in almost every review of that lens. Your lens is not unique in the weaknesses it exhibits as most lenses perform worst at wide open apertures.

You have discovered one major reason why some lenses are cheaper than others, and why lenses designed especially for low lighting levels are hugely expensive..

Your only real fix is to try and avoid shooting at apertures of f4 and larger. If that's unacceptable to you and you need a lens which performs well in low lighting conditions then you can only return the lens for a refund (much easier if you live in the UK due to the Sale of Goods Act). If you cannot get a refund then I suggest you sell the lens and buy a better quality replacement, or better still replace the zoom lens with fixed focal length prime lenses.

Zoom lenses are always an optical compromise, particularly so with zooms covering the wide to short telephoto range, and now that many dSLR's can produce low noise results at very high ISO settings there's less demand from customers for manufacturers to make lenses which have outstanding performance at wide apertures at higher cost.

Hi and welcome to FixYa,

Initially, this would be a temperature imbalance on the CCD lens. Often white spot(s) appear at night or when the temperature is cold. Workaround is to open the lens but delay taking a picture after a few seconds. The idea is allow the lens to match the ambient temperature.

Good luck and Thank you for using FixYa.

We had the same problem with a Casio Exilim. Had been stuck for months...had nearly given up until I saw another post about banging the camera pretty forcefully to get the lens unstuck. I hit it once on the bottom onto my desk(w/ paper and blotter on the desk-so soft), then twice with the back of the camera against the desk. I turned it on and the lens was unstuck!! Immediately took a couple pictures and it seems to be working fine! If the camera may be lost, you've got nothing to lose to try this out...Good luck!

i work with sonys all the time ..I do not recommend disassembling the lens section at all. unless its between lens and CCD imager but I doubt its there..

i think it is a case of defective apparture system. the system controlling the change of apparture opening has been locked. the reason may be friction in the blade movement or defective flex pcb carring the signal to the apparture motor.

Suggestion: 1. camera probably has a sharpness setting. 2. avoid wide open, F/5.6 is the sweet spot on most lenses.