The Olivon T90 comes complete with a high quality 22x-68x zoom eyepiece.

A large number of digiscopers would recommend using your scope at it's widest setting.

Most of the the pictures taken on this site were taken at the 22x setting. I decided to see just how far I could go with the zoom lens on by scope and still get acceptable results.

Using the Olivon T90 ED version at a nearby nature reserve, I focussed on a Great Tit in the distant trees.


Click thumbnail for larger image

Subject with the scope at 22x zoom and digital camera 3x zoom.

At this range the Great Tit is too far away to capture sufficient detail.


Click thumbnail for larger image

Subject with the scope at 68x zoom and digital camera 3x zoom.

At this range the scope captures a surprising amount of detail. The image was improved in Photoshop, using the levels command plus some unsharp mask.


The test subject
At maximum zoom, the T90ED has produced the goods yet again. Whilst it becomes harder to get a sharper shot as the zoom increases, (tiny movements are magnified even greater), and the available light reduces, I think it's definitely worth trying the zoom if the situation requires it. The Great Tit at 22x was too far away and not worth taking a picture, but at 68x zoom, a worthwhile image has been achieved. After taking some successful maximum zoom shots using the Olivon T90ED, I thought it would be interesting to see if there was a difference between the standard T90 and the ED version at this high magnification.

Standing in my back garden, I focussed in on my neighbours Dove House. Using identical camera settings taken from the same location on the same subject, I tested the T90 and the T90ED at 22x zoom then at 68x.

The results shown below are at 100% size straight from the camera. (Nikon Coolpix 4500).

I think that the tests show that the ED version definitely captures more detail at both 22x and 68x, which you would expect when you consider that it costs more than twice as much than the standard version.

You can see from above that on both scopes, at 68x zoom when viewing the image at 100% size with no image manipulation, some detail is lost. The smallest of movements is greatly magnified, this vastly increases the risk of a blurred image. If you do use your scope at maximum zoom and want an image that you can be happy with, I would recommend reducing the picture in size in your image editing software then apply some doses of unsharp mask to improve the final image.

Conclusion

After my tests, my opinion is that a lower magnified subject will produce a sharper brighter image, there's also less risk of camera shake. Having said that, after taking successful images of the Great Tit at 68x, I will definitely use more zoom in the future if I think the situation needs it. It's nice to know you have the flexibility that a zoom lens offers.



This is a non-commercial website.
The content is my own diary and findings. I accept no responsibility or liability if you choose to follow my advice.

The advice, reviews and opinions expressed in this website is based purely on my own findings and preferences and should be treated as guidance only. You may find other settings work better for you and your equipment.