Usefulness or otherwise of 20x fixed eyepiece (Nikon ED50 related) (1 Viewer)

Just a little update in my experiments with the ED50,regarding resolution and performance...I mentioned having a less than average performing unit and having tried to realign the lens by turning it around a few degrees at a time and performing some tests in each stage..I think I had the lens In a optimum position,but I wanted to see If it was a lot of difference indeed with the previous position.Once again loosened the objective cell anough to be able to turn the lens around a bit,this time ready to boost the image to 160X,with the scope set in a distant target(300Feet)...I started by turning the lens to the opposite position to the one I have first determined to be the right one,and focusses the scope at 20X..Yes,I had the same feeling of not reaching focus that I had when first got the scope..boosting the image at 160X I could see brutal CA In,out and in what seemed to be the best possible focus..resolution was very poor..I now started again to turn the lens first in one direction,and then in the other,making random tests ,trial and error method until I reached ,again,the best performing point in the circumference..There ,Not much CA was present even at 160X(some color,but seemed moderate)and I was able to discern ,clearly ,signs,letters and detail that was impossible to make at the worst performance point...I locked the cell in this optimum collimation point,and today tested the scope again,in very bright light,in another target ,at a slightly closer distance.
At 20X ,now,I can "feel" that the scope clearly outresolve my eyes ability to see detail (Thats what I like to see ,even at a low power,when using a scope)..At 160X ,with a very small Exit pupil,the clarity of the images is surprising and CA is VERY well controlled (Very bright ,crisp and still atmospheric conditions today,perfect visibility).
The amount of detail in the image is very satisfactory ,and whatever cant be seen just seems reasonably small to not cause any frustration..Visual Common sense...
I did this test again becasue I wanted to make sure that the lens had indeed an Optimum placement in the scope related to collimation..Whether or not other factors affected the performance of the scope in this test ,I dont know(axial tilt ?)..
What I absolutely believe by now is that a 27X eyepiece WILL grant a bit more detail in my scope than the 20X I am using now. I dont know if the difference would be huge or if this would be at the cost of any fraction of the relaxing feel that the image has at 20X.I totally agree that 50X would still be a VERY usable power to use in the ED50...Note that at 160X ,using the binos to boost the image,ER still unchanged and You have all the binocular usable ER...So,for me, it is almost easier to use this 0.3mm exit pupil,with 16mm eye relief,that 1.1mm exit pupil with 12mm eye relief

Just a quick update on my original post. Well it appears I was too quick to judge as usual, I now love the 20x! I will still be getting either the zoom or the 27x when I can get some spare cash together but I'll never give up the 20x now.

Once I accepted that its obviously not really best suited to long range IDing then it really just comes into its own as a fabulously useful, convenient and fun to use combo. I'd hate to give up the wide, bright and steady view it provides. I have a feeling that the zoom will compliment it rather well for longer range, but the view at 20xw is quite addictive I have to say, it just works really well for relaxed observation.

For example I've just been watching a fairly distant peregrine in a field and sure I could ID it with bins and it was also brighter with them but with the ed50 and 20x steadied on my lightweight tripod- just to sit, nice and relaxed at the edge of the field, just me and the peregrine and some very worried looking lapwing, ahh pure relaxed birding bliss

mulligatawny owl said:

Just a quick update on my original post. Well it appears I was too quick to judge as usual, I now love the 20x! I will still be getting either the zoom or the 27x when I can get some spare cash together but I'll never give up the 20x now.

Once I accepted that its obviously not really best suited to long range IDing then it really just comes into its own as a fabulously useful, convenient and fun to use combo. I'd hate to give up the wide, bright and steady view it provides. I have a feeling that the zoom will compliment it rather well for longer range, but the view at 20xw is quite addictive I have to say, it just works really well for relaxed observation.

For example I've just been watching a fairly distant peregrine in a field and sure I could ID it with bins and it was also brighter with them but with the ed50 and 20x steadied on my lightweight tripod- just to sit, nice and relaxed at the edge of the field, just me and the peregrine and some very worried looking lapwing, ahh pure relaxed birding bliss

Click to expand...

Good news Mr. Owl I also just bought a scope for the first time and it takes getting used to. I see you carry yours on a bike? For me, the scope is no prob on a bike as I just carry it in a rucksack. The tripod is the problem for me. I have a big heavy full size tripod that is rock steady but weighs a ton and I carry it sticking wildly out of a back pannier. What make and model is your tripod? Having a light tripod can introduce a lot of shimmer, on a windy day. Even with my heavy one, using a fixed 32x eyepiece, it shimmers if the wind is blowing hard.

Des

Deshiggins said:

Good news Mr. Owl I also just bought a scope for the first time and it takes getting used to. I see you carry yours on a bike? For me, the scope is no prob on a bike as I just carry it in a rucksack. The tripod is the problem for me. I have a big heavy full size tripod that is rock steady but weighs a ton and I carry it sticking wildly out of a back pannier. What make and model is your tripod? Having a light tripod can introduce a lot of shimmer, on a windy day. Even with my heavy one, using a fixed 32x eyepiece, it shimmers if the wind is blowing hard.

Des

Click to expand...

The tripod is a velbon maxi L. It seems steady enough so far, though I've not used it on a really windy day yet. It folds down to just 36cm so fits in my 25L rucksack. It weighs 989g so is just about manageable for a long days walk or ride. My next purchase will be a decent compact monopod I think, I'm not entirely convinced it will be much use though, I've got a cheapy walking stick type one which is pretty useless really. Another weight saving option I'm considering is one of the Joby gorillapods.

mulligatawny owl said:

The tripod is a velbon maxi L. It seems steady enough so far, though I've not used it on a really windy day yet. It folds down to just 36cm so fits in my 25L rucksack. It weighs 989g so is just about manageable for a long days walk or ride. My next purchase will be a decent compact monopod I think, I'm not entirely convinced it will be much use though, I've got a cheapy walking stick type one which is pretty useless really. Another weight saving option I'm considering is one of the Joby gorillapods.

Click to expand...

My tripod weighs 5 kilos and folds to something like 70cm so yours sounds light as a feather . I worry about how steady it would be but I am sorely tempted to look at one of the tripods in that range, just for cycling. Monopods look very very hard to keep steady but I have not tried a good one. I think it is hard to get round needing a sturdy tripod of some kind with a scope. Thanks for the info anyway!

Des

27x Ds

mulligatawny owl said:

Just a quick update on my original post. Well it appears I was too quick to judge as usual, I now love the 20x! I will still be getting either the zoom or the 27x when I can get some spare cash together but I'll never give up the 20x now

Click to expand...

Well, I just did..traded my 20X MC for a 27x DS..I had the opportunity to test both eyepieces side by side,before sending my eyepiece out,and I must say in a side by side , was very hard not to have second thoughts about trading one for the other..the 20X is wider, consideraby brighter,and more than anything easier to keep stable,specially on a light tripod. DOF differences are also quite obvious,for there is need to refocus more often with the 27X that with the 20X..Add the ergonomics as well to the comparison..the DS is a much larger ocular and keeps reminding me that I have a nose ,while the MC ocular barely met my nose bridge ..Even with the advantages already mentioned going for the 20X ,the 27X really comes closer to the image I am used to work with, and that I look for ,when using a scope..brightness was my main concern ,but even in dim light conditions the 27X stays useful ,and more detail can be attain than with the 20X.
In my mind ,and looking at specifications,the 20X is the more balanced magnification for the ED50,and a safe choice ,but in the field I gladly compromise, for now ,to the 27X.

Thanks for your update and thoughts on the 2 eyepieces. Also your experiments on the ED50 lens and what you found.