Vignetting with different scope/eyepeice combinations and Coolpix 4500 (1 Viewer)

Hi,

First post so I hope this goes in the right place etc!

Just got a Coolpix 4500 which I am currently using with my Kowa 821 and eagle eye adaptor (although not the one with the coolpix thread). With this I have to zoom to c3x to remove vignetting and initial images are pretty murky (although no doubt will be better with practice). I can get down to 2x by handheld but don't seem to have the steady hands (should drink less!).

Suspect that I would get far better results with a fluorite lens from one of the "big three" Leica APO/Zeiss Fl or Swarovski ATS 80 HD. Grateful if any of you out there using these could let me know what zoon you have to use on the 4500 to remove vignetting with the zoom eyepieces for these three (all 20-60x I believe)?

Mind you I am so impressed with the macro mode on the 4500 that I might find myself spending half my time photographine flowers/insects instead of digiscoping!

Incidentally I took a couple of test pictures thru my Swaro 8x42 ELs the other day and the difference in quality from the scope was marked especially the lack of coulour fringeing

Thanks in advance for any replies.

Ivan

Hello Ivan
Let me extend you a warm welcome to Birdfourum on behalf of the Moderators and Admin.With these kind of question you are in the right place, there is a huge pool of knowledge within the Forum and I am sure you will get helpful and friendly answers to your questions.

Unfortunately I haven’t used the Kowa scope that you have, my Digiscoping combination is the CP4500 and the Swarovski ST80HD. I can tell you that you will probably have to zoom to between 2-3X with the camera to remove all trace of vignetting, but it may depend a little on the amount of zoom your using on the scope and the type of adapter. I use the LCE one, I tend to leave my zoom at around 3X and zoom out if I have to.

All the best

Rich

Hi Ivan,
You would get less vignetting with an adapter with a direct 28mm thread on it.... some step-rings are quite deep, so taking the camera lens further away from the e.p. Bear in mind that some of the modern e.p's with twist-up/down eyecups won't allow an adapter to get quite as close to the e.p. glass as the older e.p's where you have to pull off the rubber eyecup..... the convenience factor of the eyecups on modern e.p's outweigh this small problem imho.

The cp4500's lens runs from about 8mm focal length at full wide angle to 32mm at max 4x zoom.

With the Swarovski zoom e.p. and a good (28mm) adapter, vignetting disappears at 13.2mm with the zoom @20x, 17.3mm @ 30x and 17.7mm @40x

With the Zeiss zoom e.p and a good adapter (28mm), vignetting disappears at 10.4mm with the zoom 20x, 17.5mm @ 30x and 17.1mm @ 40x.

Modern zoom e,p's go into wide angle as they get towards their max magnification, so vignetting is reduced at the top end.... though it's not much use in digiscoping as the light is still reduced.

I wouldn't worry too much about vignetting, especially with a 4mp camera... you can just crop away any vignetting in-computer and still have plenty of pixels left for a reasonably sized print (8x6 at least), and most definitely plenty of pixels for a web image.

I'm coming to the conclusion that it's better to have top (HD/APO/ED/Fluorite) glass in a small scope than standard glass in a scope with a large objective lens for digiscoping... certainly with the arrival of scopes like the Swaro' ATS65HD. The key to digiscoping success imho is the ability of the user to focus the scope via the camera's monitor, this is far easier with a sharp/high contrast image from a scope with top glass. Ideally you'd have an 80mm scope with top glass, as the larger scopes resolve more detail.
Hope that helps,
Andy Bright

And Ivan, you are right, the Nikon CP 4500 in macro mode is great. The ability to zoom in close, then see the results before you leave is heady. Strongly recommend the Xtend-a-View™ Pro LCD viewer if you don't already have one.

Thanks all

Thanks for the advice from all of you. I have got the xtenda view pro but having a little bit of a problem getting used to the grainy image - as soon as I do I'm sure it will help.

I guess that I am not the only one who is sometimes under the illusion that a second mortgage and a top notch scope will automatically make my pics turn out like Andy's (and others of course)! I guess, as Andy alluded to, practice makes perfect (or at least barely acceptable!) and I do find that my efforts are gradually getting better - though not near "gallery" standard yet.

Looking forward to Andy's review of the Zeiss which I belive from your web site you are trialling.................

Thanks folks.

Ivan