Trying different scopes and how to compare them. (2 Viewers)

[AuntySocial]

I'm looking at getting hold of a first scope and have very little experience of the format.
I aim to look at as many as possible and make some notes/scores of their qualities and features. The problem is that I don't know what exactly I'm looking for and would like some help in coming up with a test procedure that will cover the basics, e.g. a standard image at a set distance in a similar light and how to score what I see.
I'm steering towards 60-66 and probably a zoom and fixed EP. I'm aware I will find it more difficult to try fixed so might just test zooms... Budget is mid-range for new but would prefer a good second hand scope. No hurry for a scope though, I've been with bins only for 30 years.
If anyone has a basic procedure they might share I'd be very grateful.
Thanks, Adam.

 

[jring]

Hi,

first of all, welcome to birdforum!

Having had a quick look through the usual suspects for used optics in GB, the following look like they might fit your bill:

OPTICRON MM4 60EDA C/W SDL V2 15X-45X (WFV) :: In Focus - great little scope with a great zoom EP. Get a 40831 if you want a low mag (23x) wide angle fixed with that.

OPTICRON HR66A C/W HDF 28X (DD) :: In Focus - cheap option -plain glass scope with 28x wide. If you don't want to go higher, that will serve just fine.

KOWA TSN-3 C/W 30XWA (DD) :: In Focus - actually a full size scope at 77m aperture but a light one (1.2kg for body and 30x wide EP) - also the best scope money could buy in the early 90s with the great 30x wide EP. An Opticron SDLv2 or v3 can be adapted easily for higher mag views up to 54x (and it's better than the curren Kowa 20-60x zoom). I have a cherry example of this with the SDLv2 and it still compares favourably in a line of current alphas.

Used Opticron MM4 60mm ED Angled + 15-45x HDF Eyepiece | London Camera Exchange -Gloucester - Another MM4 60mm with the HDF zoom - not quite as premium as the SDLv2/v3 but still a nice EP - but 100 quid less than the other.

Used Opticron MM4 60ED c/w SDL V2 (15-45X) Straight| London Camera Exchange -Bath - yet another MM4 60 with the SDLv2 for 500 quid - if you want a straight scope (which I don't recommend).

Joachim

 

[wllmspd]

I spot a pattern… I’m very happy with my (secondhand) MM4 60mm, gives great views, much less effort than carrying a big scope. Even though I have some nice bins I have to admit that I spent pretty much all my time using just the scope the last time I went out. I’d also recommend you make a cable tie sight, makes getting on target quickly very easy, Cable-tie sighting device: IMPROVED! COLLAPSABLE!

Peter

 

[beacon hill]

Celestron Regal scopes accept 1.25" astronomical eyepieces. So will be a large choice of fixed eyepieces to choose from.

 

[pppppvvvv]

I'm looking at getting hold of a first scope and have very little experience of the format.
I aim to look at as many as possible and make some notes/scores of their qualities and features. The problem is that I don't know what exactly I'm looking for and would like some help in coming up with a test procedure that will cover the basics, e.g. a standard image at a set distance in a similar light and how to score what I see.
I'm steering towards 60-66 and probably a zoom and fixed EP. I'm aware I will find it more difficult to try fixed so might just test zooms... Budget is mid-range for new but would prefer a good second hand scope. No hurry for a scope though, I've been with bins only for 30 years.
If anyone has a basic procedure they might share I'd be very grateful.
Thanks, Adam.

If you can try models side by side, then you'll get a good idea of which one you prefer.
Test how easy you can find and focus on random subjects at varying distances.
Is the field of view wide enough for it to be useable?
If there is something in the distance, like a registration plate, see if you can make out details better with each model.

If it's 2nd hand, check for scratches on the glass, or mould inside, and check the eyecup and lens hood extend smoothly .
Also check the focus and zoom wheels are smooth with no play.

When you've narrowed down your choice, have a look at reviews on here. Although this place will go into incredible detail about differences that to be honest, as a birder, I very rarely notice.

Once you've chosen one, practice will make it work well for you. This is probably as important as choosing a scope!

 

[AuntySocial]

At the moment it is the test/score process that I'm focussed on. Being an engineer makes me takes far too long over choices like these!
I like the number plate suggestion and probably have an old one I can cart around with me.
If I were to make a target to gauge my observations on would black and white be ok or do other colour combinations show CA differently?
Btw, you all seem to have read my mind as I am certainly drawn to the MM4 60, but not exclusively. I just want to choose the best example of the make/model I eventually end up with.
Thank you all for your input.

 

[pppppvvvv]

At the moment it is the test/score process that I'm focussed on. Being an engineer makes me takes far too long over choices like these!
I like the number plate suggestion and probably have an old one I can cart around with me.
If I were to make a target to gauge my observations on would black and white be ok or do other colour combinations show CA differently?
Btw, you all seem to have read my mind as I am certainly drawn to the MM4 60, but not exclusively. I just want to choose the best example of the make/model I eventually end up with.
Thank you all for your input.

I suspect there are colour charts made for this testing that someone may be able to advise on.
Just bear in mind, once you are at different locations on different days, the results will be affected by other atmospheric conditions.

I'm probably less help from this point forward, as I believe the comparisons between models of similar prices are less important than just buying one that feels good and looks ok, then going out birding!
(I bought the wrong model for me personally, but I'd never have known in the shop. It wasn't until a couple of years later I was thinking that this really isn't working for me. FoV / minimum zoom was too tight. I needed a wider initial view)

 

[Mono]

Don't over think it. Buy a scope that you are happy with and get out and use it. There might be something 5% better on metric A but 2.5% worse on metric B but they are both great at looking at birds a bit further away.

 

[AuntySocial]

I hear you. Probably the most important thing is that it fits in a bicycle pannier!
I'll go and look through what's available.......with a notebook and numberplate ;-)

 

[Mike Crawley]

Buying one you really like looking through is a far better choice than one that’s a bit uncomfortable but passes lots of (often) irrelevant tests.
If it’s comfortable to use, you’ll use it
If it takes lots of fiddling to get it sorted out, you’ll start finding excuses to leave it in the car. or worse, at home

 

[Tringa45]

I'll go and look through what's available.......with a notebook and numberplate ;-)

You might be able to read a license plate with naked eyes at around 40 m, so I think you are going to need a more exacting target, newsprint perhaps at around 30 m in stable air conditions.
German plates have a city or district seal with 3 mm tall lettering and, despite a mediocre VA of about 0,9, I was able to read this at 66 m from an elevated position in bright sunshine in a 65 mm scope at 60x.

John

 

[Boogieshrew]

I've just been trying out a new scope and found watching insects effective. Looking for the vein patterns on the translucent wings of flies as they say on fence posts was very revealing.
As they were relatively close, any heathaze was not apparent.

 

[ANK]

I've just been trying out a new scope and found watching insects effective. Looking for the vein patterns on the translucent wings of flies as they say on fence posts was very revealing.
As they were relatively close, any heathaze was not apparent.

My favorite testing chart is the Swedish 20 Kronor Bill with Astrid Lindgren:

Link to riksbank

with a lot of microtext.

(Try to read the text in Astrid's hair with your naked eyes...)

 

[diggaan]

You might be able to read a license plate with naked eyes at around 40 m, so I think you are going to need a more exacting target, newsprint perhaps at around 30 m in stable air conditions.
German plates have a city or district seal with 3 mm tall lettering and, despite a mediocre VA of about 0,9, I was able to read this at 66 m from an elevated position in bright sunshine in a 65 mm scope at 60x.

John

I tested a little my new Opticron MM4 77 ED telescope with its SDLv3 18-54x eyepiece:

1.) I could read birding magazines 3 millimeters text height from 66 meters away at the highest magnification (54x).

2.) I also tested focusing at 160 meters away on the leaves of an aspen tree. At the highest magnification, the telescope could make out the stems (petioles) of the tree's leaves.

 

[Tringa45]

I tested a little my new Opticron MM4 77 ED telescope with its SDLv3 18-54x eyepiece:

1.) I could read birding magazines 3 millimeters text height from 66 meters away at the highest magnification (54x).

2.) I also tested focusing at 160 meters away on the leaves of an aspen tree. At the highest magnification, the telescope could make out the stems (petioles) of the tree's leaves.

A star test is perhaps better, but that sounds good - certainly not a lemon.

John

 

[Hermann]

My take:

1. The best way to test a scope if a star test. Ideally try to get decent photographs of the results.
2. The second best if a thorough comparison with a scope of known quality, ideally with a cherry. A booster can be pretty useful for such comparisons.
3. All other tests (like looking at traffic signs, number plates and the like) are better than nothing. But you don't have a clearcut baseline, so you may find a scope "good" that isn't when compared to other scopes.

What I do? I find doing reliable star tests is a bit of a hassle (Henry may disagree ... ), so I normally just do thorough comparisons with a cherry scope I know well. If both scopes seem to close in quality at high magnifications, I always also use a booster.

Hermann

 

[diggaan]

My take:

1. The best way to test a scope if a star test. Ideally try to get decent photographs of the results.
2. The second best if a thorough comparison with a scope of known quality, ideally with a cherry. A booster can be pretty useful for such comparisons.
3. All other tests (like looking at traffic signs, number plates and the like) are better than nothing. But you don't have a clearcut baseline, so you may find a scope "good" that isn't when compared to other scopes.

What I do? I find doing reliable star tests is a bit of a hassle (Henry may disagree ... ), so I normally just do thorough comparisons with a cherry scope I know well. If both scopes seem to close in quality at high magnifications, I always also use a booster.

Hermann

Thank you very much, this put my mind at ease. Because it would still take a long time to wait for me to execute the star test: you see, here where I live, shines the midnight sun..😅

So I carry out my own little tests which I feel meaningful - even if they don't compare at all to comparing with a cherry (or a lemon). At this point I just can't find anything "wrong" with scope of mine Although this is only my second telescope. Indeed, the seller's verdict was "This is good.", when he tested it to be fit for resale on a well-lit engraved test board in the store (for maybe about 5-7 minutes). But of course I do understand, that that was not the star test.

 

[diggaan]

Thank you very much, this put my mind at ease. Because it would still take a long time to wait for me to execute the star test: you see, here where I live, shines the midnight sun..😅

So I carry out my own little tests which I feel meaningful - even if they don't compare at all to comparing with a cherry (or a lemon). At this point I just can't find anything "wrong" with scope of mine Although this is only my second telescope. Indeed, the seller's verdict was "This is good.", when he tested it to be fit for resale on a well-lit engraved test board in the store (for maybe about 5-7 minutes). But of course I do understand, that that was not the star test.

Of course, this model that I use, has some limitations in performance with more than 40x magnifications, e.g. in terms of brightness and fine-tuning of focus: I've tried (quickly) twice as expensive Kowa and Meopta, and they indeed are better

 

[henry link]

Thank you very much, this put my mind at ease. Because it would still take a long time to wait for me to execute the star test: you see, here where I live, shines the midnight sun..😅

Your location is perfect for daylight star testing with an artificial star consisting of a small shiny ball (Christmas tree ornament, ball bearing, etc.). The tiny glitter point of the midnight sun reflected by the ball when it's placed perhaps 25m to 50m from your scope can function as an excellent star point.

 

[diggaan]

Of course, this model that I use, has some limitations in performance with more than 40x magnifications, e.g. in terms of brightness and fine-tuning of focus: I've tried (quickly) twice as expensive Kowa and Meopta, and they indeed are better

I feel like I need to elaborate on my post a little bit..

I continued testing my telescope.
The farthest thing I can see from my balcony are the fir trees 2.6 km away, both live and standing dead.
I can easily focus on them with 40x magnification, after rain at a temperature of +19 celsius, when the thermal fluctuation of the air is at a minimum. It is pleasant to look at that sharp image.

**********
One more thing:

I can imagine, even though I can't find it by searching this forum, that the forum has previously brought to light things that affect the kind of image you see when looking through a telescope.

So one more time,
you really should know and take these all into account when you go telescope shopping.

I wish I had known these things when the telescope fever hit me!

- the size of the diameter of the front lens (a larger front lens enables greater resolution and brightness), the material of the lens (fluorite crystal, or fluoride glass: its quality), the suitability and quality of the lens coating, the degree of success of grinding

- the type of glass of the prisms, the suitability and quality of the coatings, the degree of success of grinding

- amount of magnification:
(A larger aperture collects a lot of light, so the image is more bright and sharp, but enables a lower magnification.
A smaller aperture collects less light, so is less bright and sharp, but enables higher magnification)

- the temperature of the telescope compared to the outside temperature
-> the telescope must be tempered for approx. 1 hour before use if the inside and outside temperatures differ significantly

- the amount of thermal fluctuation between the tube and the object

- amount, direction, and gustiness of the wind -> tripod stability

- the weight of the telescope (a heavier telescope vibrates more sensitively compared to a lighter one if the stand is not stable enough)

- amount, color and type of cloudiness , direction and amount of light , is it morning, day, or evening (light)

- is there some snow on the ground or not

- is the object you are watching on a bright or on a dark background

- own vision (color vision, distance vision, night vision, astigmatism)

- the use of sunglasses and/or glasses and their optical quality

- pupil distance from the eyepiece (eye relief)

End caps:

A telescope is always a compromise between different features. There are different types of telescopes to suit your needs. At any price, you can't get a telescope that is both bright and sharp all the way through the zoom, and at the same time also compact and light