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Opticron 665ED and HR66GA ED (1 Viewer)

goon525

Member
These seem to be two similarly specified scopes, similar also in weight and not that much to choose between them in price. Can anyone assist with what the real differences are, and which might be considered preferable?
Many thanks.
 
Hi

The Hr66 ed uses a 5 element APO lens design, 3 lenses in the primary objective and 2 within the focusing lens. this combination produces an exceptionally 'flat field' with excellent 'edge to edge' sharpness with little to no curvature or 'bowing' at the image edges. The Gs 665ed is not so well corrected in this respect showing some 'bowing' and loss of sharpness at the edges, especially at higher magnifications. The latest versions (2008) of the HR66 ed also use a secondary 'ed' element within the focusing lens, further enhancing the quality of this scope, pre 2008 versions are still exceptional.
Both scopes produce very bright images, with slightly better contrast seen with the HR66 ed. The build quality of the HR66 is also better and more robust, both are nitrogen filled waterproof. both scopes show acceptable levels of CA (chromatic Abberation), or colour fringing, although again in digi-scoped images the GS665 shows more fringing.

In all events you should try the scopes out for yourself, side by side if at all possible to see which one suits you. Optically though the HR66 has the edge

steve
 
Hi goon,

I had a chance to compare both scopes side by side with zoom eyepieces recently. Whilst the GS delivered a nice and perfectly acceptable image, the HR was very good and the difference in image was quite noticeable, especially at high powers. When zoomed in at 48X, the Gs image seemed washed out, and not very sharp. By contrast, on the HR, the image was very well defined and sharp all the way up to 54X. By here it was a bit dark on a overcast day, but still very useable. In fact, both scopes were fine in terms of brightness.
Image aside, the HR is a bit heavier, but feels a lot more rugged compared to the delicate looking GS. The focussing system on the latter is very fiddly too.

Hope that helps.
 
Thanks, guys, for the comprehensive and useful replies. It does seem like the HR66 is the way to go, if I decide to buy Opticron. (I'm a Pentax DSLR user, and still considering the different approaches I could take if I go for an all Pentax solution, or Opticron's perfectly flexible alternative.) Are you aware of any online reviews of these and other relevant scopes - a Google search hasn't come up with all that much.
Thanks again.
 
A translation of it might have been! But I'm about to pick up my new HR66 GA ED, so the moment of comparison has passed. Thanks for the thought, though.
 
Goon,

you will not be disappointed with your new HR66 GA ED. Although heavier than the the GS665 GA ED it has two ED elements in it's optical system and in my opinion is both brighter, sharper offering better resolution.
 
Thanks, Chris. Just picked it up and set it up. Seems fine looking at cars parked down the road, but that may not of course be the ultimate test!
 
Hi goon,

I had a chance to compare both scopes side by side with zoom eyepieces recently. Whilst the GS delivered a nice and perfectly acceptable image, the HR was very good and the difference in image was quite noticeable, especially at high powers. When zoomed in at 48X, the Gs image seemed washed out, and not very sharp. By contrast, on the HR, the image was very well defined and sharp all the way up to 54X. By here it was a bit dark on a overcast day, but still very useable. In fact, both scopes were fine in terms of brightness.
Image aside, the HR is a bit heavier, but feels a lot more rugged compared to the delicate looking GS. The focussing system on the latter is very fiddly too.

Hope that helps.

This just goes to show why one should test the scopes instead of relying on reviews, as my testing of these two scopes gave different results :eat:

To start with, I found the HDF zoom eyepiece to give a much more 'punchy' image on both the HR66 and GS665, than the SDL zoom. Also to me, the fully rubberised GS665 looked more robust than the HR66 :eat:

Optically, the GS665 looked sharper to me, but this could be down to the excellent twin focussing controls on the GS665. Rather than finding the GS665 focussing controls to be 'fiddly', I found it very nice to use two fingers, one for each control. One finger focussed quickly with the coarser focus control, then the second finger refind the focus with the fine control. Everytime I focussed on a new bird, I was able to get quicker and finer focus with the GS665. If the optics are better on the HR66, then I really am at a loss why they didn't fit the fine focus control to the HR66 :eek!:

At high magnifications, I found the GS665 to give a better image, again this may be purely down to its excellent fine focus control. With the HR66 I was constantly focussing back and forward to find the focus 'sweet spot', but with the GS665 I was able to achieve optimum focus straight away every time.

As ever, it comes down to the individual to find the scope best suited tothem. Never right off a scope because someone says it is 'bad'!
 
I can't argue with your opinion, but what I have said agrees with opticron - the HR is a much newer, more expensive scope, which opticron claim will give the better image. The guy in the shop seemed to think so too.
As for the fine focus thing, it really made very little difference to the focus of the image for me. Why didn't they fit it to the HR66? Probably because it's not very robust mechanically, and isn't all that useful.
I do have to disagree on the robust thing though - the HR66 is a far more substantial scope, that is also fully rubberised, and, if i'm not mistaken, in a much thicker style. The old HRs are reknowned for being robust, and the new ones armour seemed to be just as good, if not better.
 
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I can't argue with your opinion, but what I have said agrees with opticron - the HR is a much newer, more expensive scope, which opticron claim will give the better image. The guy in the shop seemed to think so too.

The guy in the shop is just another human with personal perceptions ;) This only shows why I posted my reply to the 'HR66 is better than x'. ;) As I said in another post, I found the 665 to offer better resolution in dark areas. I had both scopes set up looking at the same feeder - both scopes had the HDF zoom lens. The most telling for me was looking at a Goldfinch. In areas where the blue or red was darker, I saw more detail through the 665 - the darker blues and red looked almost black to me with a loss of detail through the HR66. This may be a direct result of my eyes and not the lenses, but for me the 665 gave more convincing clours and detail.

I love music and purchased my first two hi-fi systems based on scores in hi-fi magazines. However, I hated the sound of both. I then spent several days listening to systems at dealers, by booking listening rooms. I ended up with a system at home that sounds superb to me, yet doesn't score particularly high with the mags.

As for the fine focus thing, it really made very little difference to the focus of the image for me. Why didn't they fit it to the HR66? Probably because it's not very robust mechanically, and isn't all that useful.

Ah, the not very robust comment on the fine focus is a very helpful comment - is this from personal experience or reading about examples on the web/mags? I loved the fine focus control, but not if there is evidence of it being flimsy!

As far as it not being very useful to you, I found it VERY useful indeed. I was able to focus quicker everytime. However, this was with my fingers and through my eyes - everyone will perceive it differently.

I do have to disagree on the robust thing though - the HR66 is a far more substantial scope, that is also fully rubberised, and, if i'm not mistaken, in a much thicker style. The old HRs are reknowned for being robust, and the new ones armour seemed to be just as good, if not better.

Just goes to show - I thought the 665ED looked very robust indeed |=)| I can't disagree with your comment though, because I have never owned either scope, but I did test them out for several hours and both seemed pretty well built to me. What is important though is not to choose a product based on a score or opinion (although both are useful pointers on what models to shortlist), but to base the decision on looking through the glass yourself. Only then will you REALLY know what scope best suits your eyes, perception and feel.
 
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The guy in the shop is just another human with personal perceptions This only shows why I posted my reply to the 'HR66 is better than x'.
Yes, but the guy in the shop has expertise and knows what most people prefer. I think people know to take these sort of things with a pinch of salt; I wasn't saying that HR66 is better than X, I was saying I prefered the HR to the GS.

I agree with what you say; people see things different.
This has more relevance when comparing scopes that are intended to compete with each other; for example a Zeiss 85 and a Swarovski ATS 80HD.
In this case, the HR66 is intended as opticrons top 60 ish mm scope, whereas the GS665 is intended to be below it, so the HR66 probably will be better for more people, otherwise it'd be a little pointless.

Ah, the not very robust comment on the fine focus is a very helpful comment - is this from personal experience or reading about examples on the web/mags? I loved the fine focus control, but not if there is evidence of it being flimsy!

Its probably harder to seal/waterproof, has more moving parts etc. I don't really know as such; I think it was another guy in another shop.

Just goes to show - I thought the 665ED looked very robust indeed I can't disagree with your comment though, because I have never owned either scope, but I did test them out for several hours and both seemed pretty well built to me.
The 665ED is built to be lightweight. As such, some "robustness" will likely be sacrificed, because less rigid materials are used. I'm not saying it is not robust, im sure it is pretty resistant, but it seemed inferior to the HR66 to me in this respect.

What is important though is not to choose a product based on a score or opinion (although both are useful pointers on what models to shortlist), but to base the decision on looking through the glass yourself. Only then will you REALLY know what scope best suits your eyes, perception and feel.

Yep, as I say you are right, but I never really posted my review as a " HERE IS THE RIGHT ANSWER " - just my personal observations.
 
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