HDF 40831 vs 40810 question (and other specs) (2 Viewers)

[Gzoladz74]

Hi all,

In addition to the differences that can be seen in the specs (magnification, eye reliefe, fov, etc), does anyone own both or either of these who can comment on its performance in terms of sharpness, brightness, etc? I would expect them to be similar but is some threads the 40810 is the one recommended as the "go to" eyepiece for fixed mag...not sure if because of its lower reach or another reason.

I am intersted in the 40831 to complement my SDLv2 on my MM360 and HRGAED80.

Separately, it would be great if Opticron could provide a full table comparing the features of all eyepieces in different scopes, not only including their own physical specs but also what they deliver when attached to different instruments (fov, afov, mag, etc, etc). I appreciate the info is out there between the website and the forum, but to have it all together it would be great. I would be happy to help by facilitating a template if that is of any help

 

[wllmspd]

Something like this maybe… ? Could need updating and collating.

Opticron - Eyepieces Archive

https://www.birdforum.net/attachments/scope-and-eyepiece-focal-lengths-xlsx.589390/

Peter

 

[Gzoladz74]

Something like this maybe… ? Could need updating and collating.

Opticron - Eyepieces Archive

https://www.birdforum.net/attachments/scope-and-eyepiece-focal-lengths-xlsx.589390/

Peter

Updating, collating and expanding.

 

[asp09]

I have no experience of the 40810, but I believe that eyepiece is usually recommended for digiscoping. The 40831 is my favourite eyepiece on the MM4 60; it's small, light and bright enough to be used on a dull winter day. I also have the 40858 (32x), but I prefer the 23x because of the greater depth of field. Optically it's no better than the SDLv2, but I find it much more enjoyable to use because of the wider field of view. I generally only use the zoom when it's raining.

 

[Gzoladz74]

I have no experience of the 40810, but I believe that eyepiece is usually recommended for digiscoping. The 40831 is my favourite eyepiece on the MM4 60; it's small, light and bright enough to be used on a dull winter day. I also have the 40858 (32x), but I prefer the 23x because of the greater depth of field. Optically it's no better than the SDLv2, but I find it much more enjoyable to use because of the wider field of view. I generally only use the zoom when it's raining.

Thanks asp09, very useful. That is the one I am looking to use primarily on my HR80GAED...it would deliver 38x.

 

[Gzoladz74]

Something along these lines would add a lot of value...some attributes are specific to the eyepiece so the value would be off course the same for all scopes, but you get the idea.

I would include all current eyepieces + those discontinued that still fit current scopes and all current scopes + those discontinued that still fit current eyepieces...it is a one off effort and that it just needs to be maintained.

	Eyepiece 1					Eyepiece 2
	Scope 1	Scope 2	Scope 3	Scope 4	Scope 5	Scope 1	Scope 2	Scope 3	Scope 4	Scope 5
Focal Length
Diameter
Close focus distance
Maginification
Field of view (1000m)
Field of view (angle)
AFOV
Exit pupil
Lenght
Weight
etc

 

[njekto]

I have no experience of the 40810, but I believe that eyepiece is usually recommended for digiscoping. The 40831 is my favourite eyepiece on the MM4 60; it's small, light and bright enough to be used on a dull winter day. I also have the 40858 (32x), but I prefer the 23x because of the greater depth of field. Optically it's no better than the SDLv2, but I find it much more enjoyable to use because of the wider field of view. I generally only use the zoom when it's raining.

I am interested in your experience with #40831. would you buy it with mm4/60 as your only eyepiece? I am considering mm4/60 with 23x but I wonder if I wont miss a bit more reach sdl3 could provide. saving 250e + smaller scope is tempting.

 

[Peregrine Took]

I am interested in your experience with #40831. would you buy it with mm4/60 as your only eyepiece? I am considering mm4/60 with 23x but I wonder if I wont miss a bit more reach sdl3 could provide. saving 250e + smaller scope is tempting.

I've used the 40831 with an MM4 60 along with the HDFT zoom, then sold both and bought the SDLv3. The 40831 is a very nice eyepiece, but if you're also considering the SDLv3 I don't think you'll need the 40831 - the SDLv3 is a spectacular eyepiece with a nice wide field of view and comfortable ergonomics. Obviously, the SDLv3 has the advantages of both a wider view at 15x and a longer one at 45x. If you really decide you want to scratch the 40831 itch it's inexpensive enough, but I think the best place to start is with the zoom.

The MM4 60mm is a GREAT scope, but the lack of a hood (or thread for one) was one of the biggest reasons why I sold it.
.

 

[Boogieshrew]

I agree. If you're only having one eyepiece then get the SDL3.
I have SDL2 and the 17x, 23x and 30x eyepieces. I use the SDL most but the 17x gets a lot of use too. It's so wide and bright. The 23x doesn't get much use and the 30 even less.

 

[wllmspd]

I got the 23x fixed after the SDL3. I was always a bit irritated with the SDL3 at the low end (too narrow) and sometimes at the top end (seems to dim and drop in contrast suddenly), so I normally use it at an “optimum power” around 30x or so depending on the lighting. Being able to adjust as needed.

I’ve been out a few times with just the 23x and not felt I was missing much, just a nice bright, wide view. I am sure that running a bit higher I would have seen more detail, but on those times I didn’t even use my binoculars, just the mm60 on a light tripod (with cable tie trick to get on target rapidly).

For one eyepiece I’d go with the zoom, as you can tune the best magnification. If they still sold a wide angle 27x then that maybe probably be best.

Peter

 

[njekto]

@Peregrine Took @Boogieshrew @wllmspd thanks folks, appreciate your insights.

 

[Gzoladz74]

Just get the SDLv3. The 40831 is allegedly wider, but the SDLv3 gets wider as you zoom in so you don't end up missing up much. The SDLv3 performs fairly well in both my MM360 (which lost its claimed weather proof capability as the "new-this-is-really-weather-proof, when-we-said-weather-proof-before-we-did-not-mean-weather-proof" MM3 60 was launched) and my HRGAED80.

Surely if Opticron were happy to support their marketing spill sharing hard facts and numbers for measurable specification of their intruments we would not be having this conversation...

 

[Peregrine Took]

Surely if Opticron were happy to support their marketing spill sharing hard facts and numbers for measurable specification of their intruments we would not be having this conversation...

They are woeful when it comes to providing meaningful specifications. Zero information on their eyepiece pages about field of view.... one of the most important things anyone wants to know.
.

 

[GreenRooky]

I find this page useful
Opticron - Eyepieces Archive

And this thread has some useful values for comparing the zooms
Best eyepiece for the MM4 50ED - the SDL or HDF?